Science.gov

Sample records for advancing blade concept

  1. A rotor technology assessment of the advancing blade concept

    NASA Technical Reports Server (NTRS)

    Pleasants, W. A.

    1983-01-01

    A rotor technology assessment of the Advancing Blade Concept (ABC) was conducted in support of a preliminary design study. The analytical methodology modifications and inputs, the correlation, and the results of the assessment are documented. The primary emphasis was on the high-speed forward flight performance of the rotor. The correlation data base included both the wind tunnel and the flight test results. An advanced ABC rotor design was examined; the suitability of the ABC for a particular mission was not considered. The objective of this technology assessment was to provide estimates of the performance potential of an advanced ABC rotor designed for high speed forward flight.

  2. Composite Fan Blade Design for Advanced Engine Concepts

    NASA Technical Reports Server (NTRS)

    Abumeri, Galib H.; Kuguoglu, Latife H.; Chamis, Christos C.

    2004-01-01

    The aerodynamic and structural viability of composite fan blades of the revolutionary Exo-Skeletal engine are assessed for an advanced subsonic mission using the NASA EST/BEST computational simulation system. The Exo-Skeletal Engine (ESE) calls for the elimination of the shafts and disks completely from the engine center and the attachment of the rotor blades in spanwise compression to a rotating casing. The fan rotor overall adiabatic efficiency obtained from aerodynamic analysis is estimated at 91.6 percent. The flow is supersonic near the blade leading edge but quickly transitions into a subsonic flow without any turbulent boundary layer separation on the blade. The structural evaluation of the composite fan blade indicates that the blade would buckle at a rotor speed that is 3.5 times the design speed of 2000 rpm. The progressive damage analysis of the composite fan blade shows that ply damage is initiated at a speed of 4870 rpm while blade fracture takes place at 7640 rpm. This paper describes and discusses the results for the composite blade that are obtained from aerodynamic, displacement, stress, buckling, modal, and progressive damage analyses. It will be demonstrated that a computational simulation capability is readily available to evaluate new and revolutionary technology such as the ESE.

  3. An ABC status report. [Advancing Blade Concept for XH-59A rotors

    NASA Technical Reports Server (NTRS)

    Linden, A. W.; Ruddell, A. J.

    1981-01-01

    The Advancing Blade Concept (ABC) uses two rigid counterrotating rotors in a coaxial arrangement to provide advancing blades on both sides of the aircraft. This makes use of the high dynamic pressure on the advancing side of the rotors at high forward speed, virtually ignoring the low dynamic pressure on the retreating side, while still keeping the rotor system in roll trim. Theoretically such a rotor system will maintain its lift potential as speed increases. The XH-59A was designed to investigate this theory. A description is provided of the flight test program from May, 1980 to January, 1981. A summary is presented of the knowledge gained throughout the entire program, and current pitfalls are reviewed. It is concluded that the ABC has been verified, with the XH-59A envelope of blade lift coefficient as a function of advance ratio greatly exceeding that of conventional helicopter rotor systems.

  4. SERI advanced wind turbine blades

    SciTech Connect

    Tangler, J.; Smith, B.; Jager, D.

    1992-02-01

    The primary goal of the Solar Energy Research Institute's (SERI) advanced wind turbine blades is to convert the kinetic energy in the wind into mechanical energy in an inexpensive and efficient manner. To accomplish this goal, advanced wind turbine blades have been developed by SERI that utilize unique airfoil technology. Performance characteristics of the advanced blades were verified through atmospheric testing on fixed-pitch, stall-regulated horizontal-axis wind turbines (HAWTs). Of the various wind turbine configurations, the stall-regulated HAWT dominates the market because of its simplicity and low cost. Results of the atmospheric tests show that the SERI advanced blades produce 10% to 30% more energy than conventional blades. 6 refs.

  5. SERI advanced wind turbine blades

    SciTech Connect

    Tangler, J.; Smith, B.; Jager, D.

    1992-02-01

    The primary goal of the Solar Energy Research Institute`s (SERI) advanced wind turbine blades is to convert the kinetic energy in the wind into mechanical energy in an inexpensive and efficient manner. To accomplish this goal, advanced wind turbine blades have been developed by SERI that utilize unique airfoil technology. Performance characteristics of the advanced blades were verified through atmospheric testing on fixed-pitch, stall-regulated horizontal-axis wind turbines (HAWTs). Of the various wind turbine configurations, the stall-regulated HAWT dominates the market because of its simplicity and low cost. Results of the atmospheric tests show that the SERI advanced blades produce 10% to 30% more energy than conventional blades. 6 refs.

  6. SERI advanced wind turbine blades

    NASA Astrophysics Data System (ADS)

    Tangler, J.; Smith, B.; Jager, D.

    1992-02-01

    The primary goal of the Solar Energy Research Institute's (SERI) advanced wind turbine blades is to convert the kinetic energy in the wind into mechanical energy in an inexpensive and efficient manner. To accomplish this goal, advanced wind turbine blades have been developed by SERI that utilize unique airfoil technology. Performance characteristics of the advanced blades were verified through atmospheric testing on fixed-pitch, stall-regulated horizontal-axis wind turbines (HAWTs). Of the various wind turbine configurations, the stall-regulated HAWT dominates the market because of its simplicity and low cost. Results of the atmospheric tests show that the SERI advanced blades produce 10 percent to 30 percent more energy than conventional blades.

  7. Investigation of advanced counterrotation blade configuration concepts for high speed turboprop systems. Task 4: Advanced fan section aerodynamic analysis

    NASA Technical Reports Server (NTRS)

    Crook, Andrew J.; Delaney, Robert A.

    1992-01-01

    The purpose of this study is the development of a three-dimensional Euler/Navier-Stokes flow analysis for fan section/engine geometries containing multiple blade rows and multiple spanwise flow splitters. An existing procedure developed by Dr. J. J. Adamczyk and associates and the NASA Lewis Research Center was modified to accept multiple spanwise splitter geometries and simulate engine core conditions. The procedure was also modified to allow coarse parallelization of the solution algorithm. This document is a final report outlining the development and techniques used in the procedure. The numerical solution is based upon a finite volume technique with a four stage Runge-Kutta time marching procedure. Numerical dissipation is used to gain solution stability but is reduced in viscous dominated flow regions. Local time stepping and implicit residual smoothing are used to increase the rate of convergence. Multiple blade row solutions are based upon the average-passage system of equations. The numerical solutions are performed on an H-type grid system, with meshes being generated by the system (TIGG3D) developed earlier under this contract. The grid generation scheme meets the average-passage requirement of maintaining a common axisymmetric mesh for each blade row grid. The analysis was run on several geometry configurations ranging from one to five blade rows and from one to four radial flow splitters. Pure internal flow solutions were obtained as well as solutions with flow about the cowl/nacelle and various engine core flow conditions. The efficiency of the solution procedure was shown to be the same as the original analysis.

  8. Investigation of Advanced Counterrotation Blade Configuration Concepts for High Speed Turboprop Systems. Task 2: Unsteady Ducted Propfan Analysis

    NASA Technical Reports Server (NTRS)

    Hall, Edward J.; Delaney, Robert A.; Bettner, James L.

    1991-01-01

    The primary objective was the development of a time dependent 3-D Euler/Navier-Stokes aerodynamic analysis to predict unsteady compressible transonic flows about ducted and unducted propfan propulsion systems at angle of attack. The resulting computer codes are referred to as Advanced Ducted Propfan Analysis Codes (ADPAC). A computer program user's manual is presented for the ADPAC. Aerodynamic calculations were based on a four stage Runge-Kutta time marching finite volume solution technique with added numerical dissipation. A time accurate implicit residual smoothing operator was used for unsteady flow predictions. For unducted propfans, a single H-type grid was used to discretize each blade passage of the complete propeller. For ducted propfans, a coupled system of five grid blocks utilizing an embedded C grid about the cowl leading edge was used to discretize each blade passage. Grid systems were generated by a combined algebraic/elliptic algorithm developed specifically for ducted propfans. Numerical calculations were compared with experimental data for both ducted and unducted flows.

  9. Investigation of advanced counterrotation blade configuration concepts for high speed turboprop systems. Task 5: Unsteady counterrotation ducted propfan analysis

    NASA Technical Reports Server (NTRS)

    Hall, Edward J.; Delaney, Robert A.

    1993-01-01

    The primary objective of this study was the development of a time-marching three-dimensional Euler/Navier-Stokes aerodynamic analysis to predict steady and unsteady compressible transonic flows about ducted and unducted propfan propulsion systems employing multiple blade rows. The computer codes resulting from this study are referred to as ADPAC-AOAR\\CR (Advanced Ducted Propfan Analysis Codes-Angle of Attack Coupled Row). This document is the final report describing the theoretical basis and analytical results from the ADPAC-AOACR codes developed under task 5 of NASA Contract NAS3-25270, Unsteady Counterrotating Ducted Propfan Analysis. The ADPAC-AOACR Program is based on a flexible multiple blocked grid discretization scheme permitting coupled 2-D/3-D mesh block solutions with application to a wide variety of geometries. For convenience, several standard mesh block structures are described for turbomachinery applications. Aerodynamic calculations are based on a four-stage Runge-Kutta time-marching finite volume solution technique with added numerical dissipation. Steady flow predictions are accelerated by a multigrid procedure. Numerical calculations are compared with experimental data for several test cases to demonstrate the utility of this approach for predicting the aerodynamics of modern turbomachinery configurations employing multiple blade rows.

  10. Investigation of advanced counterrotation blade configuration concepts for high speed turboprop systems. Task 4: Advanced fan section aerodynamic analysis computer program user's manual

    NASA Technical Reports Server (NTRS)

    Crook, Andrew J.; Delaney, Robert A.

    1992-01-01

    The computer program user's manual for the ADPACAPES (Advanced Ducted Propfan Analysis Code-Average Passage Engine Simulation) program is included. The objective of the computer program is development of a three-dimensional Euler/Navier-Stokes flow analysis for fan section/engine geometries containing multiple blade rows and multiple spanwise flow splitters. An existing procedure developed by Dr. J. J. Adamczyk and associates at the NASA Lewis Research Center was modified to accept multiple spanwise splitter geometries and simulate engine core conditions. The numerical solution is based upon a finite volume technique with a four stage Runge-Kutta time marching procedure. Multiple blade row solutions are based upon the average-passage system of equations. The numerical solutions are performed on an H-type grid system, with meshes meeting the requirement of maintaining a common axisymmetric mesh for each blade row grid. The analysis was run on several geometry configurations ranging from one to five blade rows and from one to four radial flow splitters. The efficiency of the solution procedure was shown to be the same as the original analysis.

  11. Investigation of advanced counterrotation blade configuration concepts for high speed turboprop systems. Task 3: Advanced fan section grid generator final report and computer program user's manual

    NASA Technical Reports Server (NTRS)

    Crook, Andrew J.; Delaney, Robert A.

    1991-01-01

    A procedure is studied for generating three-dimensional grids for advanced turbofan engine fan section geometries. The procedure constructs a discrete mesh about engine sections containing the fan stage, an arbitrary number of axisymmetric radial flow splitters, a booster stage, and a bifurcated core/bypass flow duct with guide vanes. The mesh is an h-type grid system, the points being distributed with a transfinite interpolation scheme with axial and radial spacing being user specified. Elliptic smoothing of the grid in the meridional plane is a post-process option. The grid generation scheme is consistent with aerodynamic analyses utilizing the average-passage equation system developed by Dr. John Adamczyk of NASA Lewis. This flow solution scheme requires a series of blade specific grids each having a common axisymmetric mesh, but varying in the circumferential direction according to the geometry of the specific blade row.

  12. Advanced turbine blade tip seal system

    NASA Technical Reports Server (NTRS)

    Zelahy, J. W.

    1981-01-01

    An advanced blade/shroud system designed to maintain close clearance between blade tips and turbine shrouds and at the same time, be resistant to environmental effects including high temperature oxidation, hot corrosion, and thermal cycling is described. Increased efficiency and increased blade life are attained by using the advanced blade tip seal system. Features of the system include improved clearance control when blade tips preferentially wear the shrouds and a superior single crystal superalloy tip. The tip design, joint location, characterization of the single crystal tip alloy, the abrasive tip treatment, and the component and engine test are among the factors addressed. Results of wear testing, quality control plans, and the total manufacturing cycle required to fully process the blades are also discussed.

  13. Advanced optical blade tip clearance measurement system

    NASA Technical Reports Server (NTRS)

    Ford, M. J.; Honeycutt, R. E.; Nordlund, R. E.; Robinson, W. W.

    1978-01-01

    An advanced electro-optical system was developed to measure single blade tip clearances and average blade tip clearances between a rotor and its gas path seal in an operating gas turbine engine. This system is applicable to fan, compressor, and turbine blade tip clearance measurement requirements, and the system probe is particularly suitable for operation in the extreme turbine environment. A study of optical properties of blade tips was conducted to establish measurement system application limitations. A series of laboratory tests was conducted to determine the measurement system's operational performance characteristics and to demonstrate system capability under simulated operating gas turbine environmental conditions. Operational and environmental performance test data are presented.

  14. SCIENCE BRIEF: ADVANCED CONCEPTS

    EPA Science Inventory

    Research on advanced concepts will evaluate and demonstrate the application of innovative infrastructure designs, management procedures and operational approaches. Advanced concepts go beyond simple asset management. The infusion of these advanced concepts into established wastew...

  15. Advanced turbofan blade refurbishment technique

    SciTech Connect

    Roberts, W.B.

    1995-10-01

    The purpose of the work reported here is to investigate whether the lessons learned from the work of Suder et al. can be used to reduce the in-service performance deterioration of a fan on a high bypass ratio turbofan engine. To this end, a back-to-back test was done on the fan of an RB211-22B engine with the cooperation of Delta Airlines. The fan and engine were first overhauled per normal airline practice and cell-tested to establish that the engine performance met flight acceptance standards. This test, which the engine passed, also established a performance baseline for the overhauled engine. At this point the fan blade leading edge had not been filed or scraped and the blade surfaces had not been polished because the leading edge damage and blade surface roughness fell within the acceptable limits specified by the manufacturer for normal overhaul practice. After the cell test, the fan was removed from the engine and sent to Sermatech International where the following additional operations were performed: (1) the blade surfaces were polished to a finish of 20 rms {micro}in; (2) leading edge roughness due to particle impact damage was removed and the leading edge was polished to a finish of 20 rms {micro}in; (3) the leading edge shape was rounded and the leading edge thickness was reduced over the first 5--10% of chord. Test results indicated a 0.7% drop in thrust specific fuel consumption (lb fuel/lb thrust/hr) relative to the baseline engine after the enhanced fan overhaul. Based on the results of Suder et al. (1995) it appears that 70--80% of this performance gain is due to the thin smooth leading edge and the remainder to the highly polished finish of the blade.

  16. Investigation of advanced counterrotation blade configuration concepts for high speed turboprop systems. Task 5: Unsteady counterrotation ducted propfan analysis. Computer program user's manual

    NASA Technical Reports Server (NTRS)

    Hall, Edward J.; Delaney, Robert A.; Adamczyk, John J.; Miller, Christopher J.; Arnone, Andrea; Swanson, Charles

    1993-01-01

    The primary objective of this study was the development of a time-marching three-dimensional Euler/Navier-Stokes aerodynamic analysis to predict steady and unsteady compressible transonic flows about ducted and unducted propfan propulsion systems employing multiple blade rows. The computer codes resulting from this study are referred to as ADPAC-AOACR (Advanced Ducted Propfan Analysis Codes-Angle of Attack Coupled Row). This report is intended to serve as a computer program user's manual for the ADPAC-AOACR codes developed under Task 5 of NASA Contract NAS3-25270, Unsteady Counterrotating Ducted Propfan Analysis. The ADPAC-AOACR program is based on a flexible multiple blocked grid discretization scheme permitting coupled 2-D/3-D mesh block solutions with application to a wide variety of geometries. For convenience, several standard mesh block structures are described for turbomachinery applications. Aerodynamic calculations are based on a four-stage Runge-Kutta time-marching finite volume solution technique with added numerical dissipation. Steady flow predictions are accelerated by a multigrid procedure. Numerical calculations are compared with experimental data for several test cases to demonstrate the utility of this approach for predicting the aerodynamics of modern turbomachinery configurations employing multiple blade rows.

  17. Investigation of advanced counterrotation blade configuration concepts for high speed turboprop systems. Task 2: Unsteady ducted propfan analysis computer program users manual

    NASA Technical Reports Server (NTRS)

    Hall, Edward J.; Delaney, Robert A.; Bettner, James L.

    1991-01-01

    The primary objective of this study was the development of a time-dependent three-dimensional Euler/Navier-Stokes aerodynamic analysis to predict unsteady compressible transonic flows about ducted and unducted propfan propulsion systems at angle of attack. The computer codes resulting from this study are referred to as Advanced Ducted Propfan Analysis Codes (ADPAC). This report is intended to serve as a computer program user's manual for the ADPAC developed under Task 2 of NASA Contract NAS3-25270, Unsteady Ducted Propfan Analysis. Aerodynamic calculations were based on a four-stage Runge-Kutta time-marching finite volume solution technique with added numerical dissipation. A time-accurate implicit residual smoothing operator was utilized for unsteady flow predictions. For unducted propfans, a single H-type grid was used to discretize each blade passage of the complete propeller. For ducted propfans, a coupled system of five grid blocks utilizing an embedded C-grid about the cowl leading edge was used to discretize each blade passage. Grid systems were generated by a combined algebraic/elliptic algorithm developed specifically for ducted propfans. Numerical calculations were compared with experimental data for both ducted and unducted propfan flows. The solution scheme demonstrated efficiency and accuracy comparable with other schemes of this class.

  18. Test evaluation of a laminated wood wind turbine blade concept

    NASA Technical Reports Server (NTRS)

    Faddoul, J. R.

    1981-01-01

    A series of tests conducted on a root end section of a laminated wood wind turbine blade are reported. The blade to hub transition of the wood blade uses steel studs cast into the wood D spar with a filled epoxy. Both individual studs and a full scale, short length, root section were tested. Results indicate that the bonded stud concept is more than adequate for both the 30 year life fatigue loads and for the high wind or hurricane gust loads.

  19. Advanced Airspace Concept

    NASA Technical Reports Server (NTRS)

    Erzberger, Heinz

    2002-01-01

    A general overview of the Advanced Airspace Concept (AAC) is presented. The topics include: 1) Limitations of the existing system; 2) The Advanced Airspace Concept; 3) Candidate architecture for the AAC; 4) Separation assurance and conflict avoidance system (TSAFE); and 5) Ground-Air Interactions. This paper is in viewgraph form.

  20. Advanced propulsion concepts

    NASA Technical Reports Server (NTRS)

    Frisbee, Robert H.

    1991-01-01

    A variety of Advanced Propulsion Concepts (APC) is discussed. The focus is on those concepts that are sufficiently near-term that they could be developed for the Space Exploration Initiative. High-power (multi-megawatt) electric propulsion, solar sails, tethers, and extraterrestrial resource utilization concepts are discussed. A summary of these concepts and some general conclusions on their technology development needs are presented.

  1. Experimental performance and acoustic investigation of modern, counterrotating blade concepts

    NASA Technical Reports Server (NTRS)

    Hoff, G. E.

    1990-01-01

    The aerodynamic, acoustic, and aeromechanical performance of counterrotating blade concepts were evaluated both theoretically and experimentally. Analytical methods development and design are addressed. Utilizing the analytical methods which evolved during the conduct of this work, aerodynamic and aeroacoustic predictions were developed, which were compared to NASA and GE wind tunnel test results. The detailed mechanical design and fabrication of five different composite shell/titanium spar counterrotating blade set configurations are presented. Design philosophy, analyses methods, and material geometry are addressed, as well as the influence of aerodynamics, aeromechanics, and aeroacoustics on the design procedures. Blade fabrication and quality control procedures are detailed; bench testing procedures and results of blade integrity verification are presented; and instrumentation associated with the bench testing also is identified. Additional hardware to support specialized testing is described, as are operating blade instrumentation and the associated stress limits. The five counterrotating blade concepts were scaled to a tip diameter of 2 feet, so they could be incorporated into MPS (model propulsion simulators). Aerodynamic and aeroacoustic performance testing was conducted in the NASA Lewis 8 x 6 supersonic and 9 x 15 V/STOL (vertical or short takeoff and landing) wind tunnels and in the GE freejet anechoic test chamber (Cell 41) to generate an experimental data base for these counterrotating blade designs. Test facility and MPS vehicle matrices are provided, and test procedures are presented. Effects on performance of rotor-to-rotor spacing, angle-of-attack, pylon proximity, blade number, reduced-diameter aft blades, and mismatched rotor speeds are addressed. Counterrotating blade and specialized aeromechanical hub stability test results are also furnished.

  2. Advanced concepts for acceleration

    SciTech Connect

    Keefe, D.

    1986-07-01

    Selected examples of advanced accelerator concepts are reviewed. Such plasma accelerators as plasma beat wave accelerator, plasma wake field accelerator, and plasma grating accelerator are discussed particularly as examples of concepts for accelerating relativistic electrons or positrons. Also covered are the pulsed electron-beam, pulsed laser accelerator, inverse Cherenkov accelerator, inverse free-electron laser, switched radial-line accelerators, and two-beam accelerator. Advanced concepts for ion acceleration discussed include the electron ring accelerator, excitation of waves on intense electron beams, and two-wave combinations. (LEW)

  3. Advanced space propulsion concepts

    NASA Technical Reports Server (NTRS)

    Lapointe, Michael R.

    1993-01-01

    The NASA Lewis Research Center has been actively involved in the evaluation and development of advanced spacecraft propulsion. Recent program elements have included high energy density propellants, electrode less plasma thruster concepts, and low power laser propulsion technology. A robust advanced technology program is necessary to develop new, cost-effective methods of spacecraft propulsion, and to continue to push the boundaries of human knowledge and technology.

  4. Advanced Blade Manufacturing Project - Final Report

    SciTech Connect

    POORE, ROBERT Z.

    1999-08-01

    The original scope of the project was to research improvements to the processes and materials used in the manufacture of wood-epoxy blades, conduct tests to qualify any new material or processes for use in blade design and subsequently build and test six blades using the improved processes and materials. In particular, ABM was interested in reducing blade cost and improving quality. In addition, ABM needed to find a replacement material for the mature Douglas fir used in the manufacturing process. The use of mature Douglas fir is commercially unacceptable because of its limited supply and environmental concerns associated with the use of mature timber. Unfortunately, the bankruptcy of FloWind in June 1997 and a dramatic reduction in AWT sales made it impossible for ABM to complete the full scope of work. However, sufficient research and testing were completed to identify several promising changes in the blade manufacturing process and develop a preliminary design incorporating these changes.

  5. Advanced Civilian Aeronautical Concepts

    NASA Technical Reports Server (NTRS)

    Bushnell, Dennis M.

    1996-01-01

    Paper discusses alternatives to currently deployed systems which could provide revolutionary improvements in metrics applicable to civilian aeronautics. Specific missions addressed include subsonic transports, supersonic transports and personal aircraft. These alternative systems and concepts are enabled by recent and envisaged advancements in electronics, communications, computing and Designer Fluid Mechanics in conjunction with a design approach employing extensive synergistic interactions between propulsion, aerodynamics and structures.

  6. Advanced Concept Modeling

    NASA Technical Reports Server (NTRS)

    Chaput, Armand; Johns, Zachary; Hodges, Todd; Selfridge, Justin; Bevirt, Joeben; Ahuja, Vivek

    2015-01-01

    Advanced Concepts Modeling software validation, analysis, and design. This was a National Institute of Aerospace contract with a lot of pieces. Efforts ranged from software development and validation for structures and aerodynamics, through flight control development, and aeropropulsive analysis, to UAV piloting services.

  7. Advanced radiator concepts

    NASA Technical Reports Server (NTRS)

    Diem-Kirsop, P. S.

    1985-01-01

    The liquid droplet radiator and the liquid belt radiator currently under study by the NASA LeRC are discussed. These advanced concepts offer benefits in reduced mass, compact stowage, and ease of deployment. Operation and components of the radiators are described, heat transfer characteristics are discussed, and critical technologies are identified. The impact of the radiators on large power systems is also assessed.

  8. Advanced SCADA concepts

    SciTech Connect

    Sciacca, S.C. ); Block, W.R. )

    1995-01-01

    The typical utility system planner faces a wide variety of concepts and applications to consider when procuring a supervisory control and data acquisition (SCADA) system. The system's performance requirements are influenced by an arena of rapidly advancing technologies and a highly competitive business environment. Unlike other elements of the electric utility industry, these changes are not evolving specifically for the SCADA industry; they are being driven by other technology forums, with a profound impact on the SCADA system of the future. This article explores some of these concepts and suggests technology and business issues to consider when planning for the SCADA system of tomorrow.

  9. Advanced Sensor Concepts

    NASA Technical Reports Server (NTRS)

    Alhorn, D. C.; Howard, D. E.; Smith, D. A.

    2005-01-01

    The Advanced Sensor Concepts project was conducted under the Center Director's Discretionary Fund at the Marshall Space Flight Center. Its objective was to advance the technology originally developed for the Glovebox Integrated Microgravity Isolation Technology project. The objective of this effort was to develop and test several new motion sensors. To date, the investigators have invented seven new technologies during this endeavor and have conceived several others. The innovative basic sensor technology is an absolute position sensor. It employs only two active components, and it is simple, inexpensive, reliable, repeatable, lightweight, and relatively unobtrusive. Two sensors can be utilized in the same physical space to achieve redundancy. The sensor has micrometer positional accuracy and can be configured as a two- or three-dimensional sensor. The sensor technology has the potential to pioneer a new class of linear and rotary sensors. This sensor is the enabling technology for autonomous assembly of modular structures in space and on extraterrestrial locations.

  10. Large-Scale Advanced Prop-Fan (LAP) blade design

    NASA Technical Reports Server (NTRS)

    Violette, John A.; Sullivan, William E.; Turnberg, Jay E.

    1984-01-01

    This report covers the design analysis of a very thin, highly swept, propeller blade to be used in the Large-Scale Advanced Prop-Fan (LAP) test program. The report includes: design requirements and goals, a description of the blade configuration which meets requirements, a description of the analytical methods utilized/developed to demonstrate compliance with the requirements, and the results of these analyses. The methods described include: finite element modeling, predicted aerodynamic loads and their application to the blade, steady state and vibratory response analyses, blade resonant frequencies and mode shapes, bird impact analysis, and predictions of stalled and unstalled flutter phenomena. Summarized results include deflections, retention loads, stress/strength comparisons, foreign object damage resistance, resonant frequencies and critical speed margins, resonant vibratory mode shapes, calculated boundaries of stalled and unstalled flutter, and aerodynamic and acoustic performance calculations.

  11. Advanced microwave processing concepts

    SciTech Connect

    Lauf, R.J.; McMillan, A.D.; Paulauskas, F.L.

    1997-04-01

    The purpose of this work is to explore the feasibility of several advanced microwave processing concepts to develop new energy-efficient materials and processes. The project includes two tasks: (1) commercialization of the variable-frequency microwave furnace; and (2) microwave curing of polymeric materials. The variable frequency microwave furnace, whose initial conception and design was funded by the AIM Materials Program, allows the authors, for the first time, to conduct microwave processing studies over a wide frequency range. This novel design uses a high-power traveling wave tube (TWT) originally developed for electronic warfare. By using this microwave source, one can not only select individual microwave frequencies for particular experiments, but also achieve uniform power densities over a large area by the superposition of many different frequencies. Microwave curing of various thermoset resins will be studied because it holds the potential of in-situ curing of continuous-fiber composites for strong, lightweight components or in-situ curing of adhesives, including metal-to-metal. Microwave heating can shorten curing times, provided issues of scaleup, uniformity, and thermal management can be adequately addressed.

  12. Advanced microwave processing concepts

    SciTech Connect

    Lauf, R.J.; McMillan, A.D.; Paulauskas, F.L.

    1995-05-01

    The purpose of this work is to explore the feasibility of several advanced microwave processing concepts to develop new energy-efficient materials and processes. The project includes two tasks: (1) commercialization of the variable-frequency microwave furnace; and (2) microwave curing of polymer composites. The variable frequency microwave furnace, whose initial conception and design was funded by the AIC Materials Program, will allow us, for the first time, to conduct microwave processing studies over a wide frequency range. This novel design uses a high-power traveling wave tube (TWT) originally developed for electronic warfare. By using this microwave source, one can not only select individual microwave frequencies for particular experiments, but also achieve uniform power densities over a large area by the superposition of many different frequencies. Microwave curing of thermoset resins will be studied because it hold the potential of in-situ curing of continuous-fiber composites for strong, lightweight components. Microwave heating can shorten curing times, provided issues of scaleup, uniformity, and thermal management can be adequately addressed.

  13. ADVANCED SULFUR CONTROL CONCEPTS

    SciTech Connect

    Apostolos A. Nikolopoulos; Santosh K. Gangwal; William J. McMichael; Jeffrey W. Portzer

    2003-01-01

    Conventional sulfur removal in integrated gasification combined cycle (IGCC) power plants involves numerous steps: COS (carbonyl sulfide) hydrolysis, amine scrubbing/regeneration, Claus process, and tail-gas treatment. Advanced sulfur removal in IGCC systems involves typically the use of zinc oxide-based sorbents. The sulfides sorbent is regenerated using dilute air to produce a dilute SO{sub 2} (sulfur dioxide) tail gas. Under previous contracts the highly effective first generation Direct Sulfur Recovery Process (DSRP) for catalytic reduction of this SO{sub 2} tail gas to elemental sulfur was developed. This process is currently undergoing field-testing. In this project, advanced concepts were evaluated to reduce the number of unit operations in sulfur removal and recovery. Substantial effort was directed towards developing sorbents that could be directly regenerated to elemental sulfur in an Advanced Hot Gas Process (AHGP). Development of this process has been described in detail in Appendices A-F. RTI began the development of the Single-step Sulfur Recovery Process (SSRP) to eliminate the use of sorbents and multiple reactors in sulfur removal and recovery. This process showed promising preliminary results and thus further process development of AHGP was abandoned in favor of SSRP. The SSRP is a direct Claus process that consists of injecting SO{sub 2} directly into the quenched coal gas from a coal gasifier, and reacting the H{sub 2}S-SO{sub 2} mixture over a selective catalyst to both remove and recover sulfur in a single step. The process is conducted at gasifier pressure and 125 to 160 C. The proposed commercial embodiment of the SSRP involves a liquid phase of molten sulfur with dispersed catalyst in a slurry bubble-column reactor (SBCR).

  14. Advanced Technology Blade testing on the XV-15 Tilt Rotor Research Aircraft

    NASA Technical Reports Server (NTRS)

    Wellman, Brent

    1992-01-01

    The XV-15 Tilt Rotor Research Aircraft has just completed the first series of flight tests with the Advanced Technology Blade (ATB) rotor system. The ATB are designed specifically for flight research and provide the ability to alter blade sweep and tip shape. A number of problems were encountered from first installation through envelope expansion to airplane mode flight that required innovative solutions to establish a suitable flight envelope. Prior to operation, the blade retention hardware had to be requalified to a higher rated centrifugal load, because the blade weight was higher than expected. Early flights in the helicopter mode revealed unacceptably high vibratory control system loads which required a temporary modification of the rotor controls to achieve higher speed flight and conversion to airplane mode. The airspeed in airplane mode was limited, however, because of large static control loads. Furthermore, analyses based on refined ATB blade mass and inertia properties indicated a previously unknown high-speed blade mode instability, also requiring airplane-mode maximum airspeed to be restricted. Most recently, a structural failure of an ATB cuff (root fairing) assembly retention structure required a redesign of the assembly. All problems have been addressed and satisfactory solutions have been found to allow continued productive flight research of the emerging tilt rotor concept.

  15. Optimal design application on the advanced aeroelastic rotor blade

    NASA Technical Reports Server (NTRS)

    Wei, F. S.; Jones, R.

    1985-01-01

    The vibration and performance optimization procedure using regression analysis was successfully applied to an advanced aeroelastic blade design study. The major advantage of this regression technique is that multiple optimizations can be performed to evaluate the effects of various objective functions and constraint functions. The data bases obtained from the rotorcraft flight simulation program C81 and Myklestad mode shape program are analytically determined as a function of each design variable. This approach has been verified for various blade radial ballast weight locations and blade planforms. This method can also be utilized to ascertain the effect of a particular cost function which is composed of several objective functions with different weighting factors for various mission requirements without any additional effort.

  16. Improved blade profile loss and deviation angle models for advanced transonic compressor bladings. Part 2: A model for supersonic flow

    SciTech Connect

    Koenig, W.M.; Hennecke, D.K.; Fottner, L.

    1996-01-01

    New blading concepts as used in modern transonic axial-flow compressors require improved loss and deviation angle correlations. The new model presented in this paper incorporates several elements and treats blade-row flows having subsonic and supersonic inlet conditions separately. The second part of the present report focuses on the extension of a well-known correlation for cascade losses at supersonic inlet flows. It was originally established for DCA bladings and is now modified to reflect the flow situation in blade rows having low-cambered, arbitrarily designed blades including precompression blades. Finally, the steady loss increase from subsonic to supersonic inlet-flow velocities demonstrates the matched performance of the different correlations of the new model.

  17. Wind turbine generator rotor blade concepts with low cost potential

    NASA Technical Reports Server (NTRS)

    Sullivan, T. L.; Cahill, T. P.; Griffee, D. G., Jr.; Gewehr, H. W.

    1977-01-01

    Four processed for producing blades are examined. Two use filament winding techniques and two involve filling a mold or form to produce all or part of a blade. The processes are described and a comparison is made of cost, material properties, design and free vibration characteristics. Conclusions are made regarding the feasibility of each process to produce low cost, structurally adequate blades.

  18. Advanced Welding Concepts

    NASA Technical Reports Server (NTRS)

    Ding, Robert J.

    2010-01-01

    Four advanced welding techniques and their use in NASA are briefly reviewed in this poster presentation. The welding techniques reviewed are: Solid State Welding, Friction Stir Welding (FSW), Thermal Stir Welding (TSW) and Ultrasonic Stir Welding.

  19. Materials for advanced turbine engines. Volume 1: Advanced blade tip seal system

    NASA Technical Reports Server (NTRS)

    Zelahy, J. W.; Fairbanks, N. P.

    1982-01-01

    Project 3, the subject of this technical report, was structured toward the successful engine demonstration of an improved-efficiency, long-life, tip-seal system for turbine blades. The advanced tip-seal system was designed to maintain close operating clearances between turbine blade tips and turbine shrouds and, at the same time, be resistant to environmental effects including high-temperature oxidation, hot corrosion, and thermal cycling. The turbine blade tip comprised an environmentally resistant, activated-diffussion-bonded, monocrystal superalloy combined with a thin layer of aluminium oxide abrasive particles entrapped in an electroplated NiCr matrix. The project established the tip design and joint location, characterized the single-crystal tip alloy and abrasive tip treatment, and established the manufacturing and quality-control plans required to fully process the blades. A total of 171 blades were fully manufactured, and 100 were endurance and performance engine-tested.

  20. Advanced ramjet concepts program

    NASA Technical Reports Server (NTRS)

    Leingang, J. L.

    1992-01-01

    Uniquely advantageous features, on both the performance and weight sides of the ledger, can be achieved through synergistic design integration of airbreathing and rocket technologies in the development of advanced orbital space transport propulsion systems of the combined cycle type. In the context of well understood advanced airbreathing and liquid rocket propulsion principles and practices, this precept of synergism is advanced mainly through six rather specific examples. These range from the detailed component level to the overall vehicle system level as follows: using jet compression; achieving a high area ratio rocket nozzle; ameliorating gas generator cycle rocket system deficiencies; using the in-duct special rocket thrust chamber assembly as the principal scramjet fuel injection operation; using the unstowed, covered fan as a duct closure for effecting high area ratio rocket mode operation; and creating a unique airbreathing rocket system via the onboard, cryogenic hydrogen induced air liquefaction process.

  1. Demonstration of an elastically coupled twist control concept for tilt rotor blade application

    NASA Technical Reports Server (NTRS)

    Lake, R. C.; Nixon, M. W.; Wilbur, M. L.; Singleton, J. D.; Mirick, P. H.

    1994-01-01

    The purpose of this Note is to present results from an analytic/experimental study that investigated the potential for passively changing blade twist through the use of extension-twist coupling. A set of composite model rotor blades was manufactured from existing blade molds for a low-twist metal helicopter rotor blade, with a view toward establishing a preliminary proof concept for extension-twist-coupled rotor blades. Data were obtained in hover for both a ballasted and unballasted blade configuration in sea-level atmospheric conditions. Test data were compared with results obtained from a geometrically nonlinear analysis of a detailed finite element model of the rotor blade developed in MSC/NASTRAN.

  2. Updated Assessment of an Open Rotor Airplane Using an Advanced Blade Design

    NASA Technical Reports Server (NTRS)

    Hendricks, Eric S.; Berton, Jeffrey J.; Haller, William J.; Tong, Michael T.; Guynn, Mark D.

    2013-01-01

    Application of open rotor propulsion systems (historically referred to as "advanced turboprops" or "propfans") to subsonic transport aircraft received significant attention and research in the 1970s and 1980s when fuel efficiency was the driving focus of aeronautical research. Recent volatility in fuel prices and concern for aviation's environmental impact have renewed interest in open rotor propulsion, and revived research by NASA and a number of engine manufacturers. Over the last few years, NASA has revived and developed analysis capabilities to assess aircraft designs with open rotor propulsion systems. These efforts have been described in several previous papers along with initial results from applying these capabilities. The initial results indicated that open rotor engines have the potential to provide large reductions in fuel consumption and emissions. Initial noise analysis indicated that current noise regulations can be met with modern baseline blade designs. Improved blades incorporating low-noise features are expected to result in even lower noise levels. This paper describes improvements to the initial assessment, plus a follow-on study using a more advanced open rotor blade design to power the advanced singleaisle transport. The predicted performance and environmental results of these two advanced open rotor concepts are presented and compared.

  3. Advanced sulfur control concepts

    SciTech Connect

    Harrison, D.P.; Lopez-Ortiz, A.; White, J.D.; Groves, F.R. Jr.

    1995-11-01

    The primary objective of this study is the direct production of elemental sulfur during the regeneration of high temperature desulfurization sorbents. Three possible regeneration concepts were identified as a result of a literature search. The potential for elemental sulfur production from a number of candidate metal oxide sorbents using each regeneration concept was evaluated on the basis of a thermodynamic analysis. Two candidate sorbents, Fe{sub 2}O{sub 3} and CeO{sub 2} were chosen for experimental testing. The experimental test program using both electrobalance and fixed-bed reactor sis now getting underway. The objective is to determine reaction conditions--temperature, pressure, space velocity, and regeneration feed gas composition--which will maximize the yield of elemental sulfur in the regeneration product gas. Experimental results are to be used to define a conceptual desulfurization-regeneration process and to provide a preliminary economic evaluation.

  4. Progress in advanced accelerator concepts

    SciTech Connect

    Sessler, A.M.

    1994-08-01

    A review is given of recent progress in this field, drawing heavily upon material presented at the Workshop on Advanced Accelerator Concepts, The Abbey, June 12--18, 1994. Attention is addressed to (1) plasma based concepts, (2) photo-cathodes, (3) radio frequency sources and Two-Beam Accelerators, (4) near and far-field schemes (including collective accelerators), (5) beam handling and conditioning, and (6) exotic collider concepts (such as photon colliders and muon colliders).

  5. Teach Deflection Concepts with Hacksaw Blades and Rubber Bands

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2013-01-01

    Technology and engineering educators can use a simple hacksaw blade to help students learn about deflection, as that which occurs in a beam. Here the beam is fixed at one end and allowed to deflect in a manner that is easy to see and measure--the hacksaw blade represents a cantilever, an overhanging structure. This simple and very inexpensive…

  6. Advanced Concepts. Chapter 21

    NASA Technical Reports Server (NTRS)

    Johnson, Les; Mulqueen, Jack

    2013-01-01

    Before there is a funded space mission, there must be a present need for the mission. Space science and exploration are expensive, and without a well-defined and justifiable need, no one is going to commit significant funding for any space endeavor. However, as discussed in Chapter 1, applications of space technology and many and broad, hence there are many ways to determine and establish a mission need. Robotic science missions are justified by their science return. To be selected for flight, questions like these must be addressed: What is the science question that needs answering, and will the proposed mission be the most cost-effective way to answer it? Why does answering the question require an expensive space flight, instead of some ground-based alternative? If the question can only be answered by flying in space, then why is this approach better than other potential approaches? How much will it cost? And is the technology required to answer the question in hand and ready to use? If not, then how much will it cost and how long will it take to mature the technology to a usable level? There are also many ways to justify human exploration missions, including science return, technology advancement, as well as intangible reasons, such as national pride. Nonetheless, many of the questions that need answering, are similar to those for robotic science missions: Where are the people going, why, and will the proposed mission be the most cost-effective way to get there? What is the safest method to achieve the goal? How much will it cost? And is the technology required to get there and keep the crew alive in hand and ready to use? If not, then how much will it cost and how long will it take to mature the technology to a usable level? Another reason for some groups sending spacecraft into space is for profit. Telecommunications, geospatial imaging, and tourism are examples of proven, market-driven space missions and applications. For this specific set of users, the

  7. Advanced 3D inverse method for designing turbomachine blades

    SciTech Connect

    Dang, T.

    1995-10-01

    To meet the goal of 60% plant-cycle efficiency or better set in the ATS Program for baseload utility scale power generation, several critical technologies need to be developed. One such need is the improvement of component efficiencies. This work addresses the issue of improving the performance of turbo-machine components in gas turbines through the development of an advanced three-dimensional and viscous blade design system. This technology is needed to replace some elements in current design systems that are based on outdated technology.

  8. Advanced 3D inverse method for designing turbomachine blades

    SciTech Connect

    Dang, T.

    1995-12-31

    To meet the goal of 60% plant-cycle efficiency or better set in the ATS Program for baseload utility scale power generation, several critical technologies need to be developed. One such need is the improvement of component efficiencies. This work addresses the issue of improving the performance of turbo-machine components in gas turbines through the development of an advanced three-dimensional and viscous blade design system. This technology is needed to replace some elements in current design systems that are based on outdated technology.

  9. The SNL100-02 blade : advanced core material design studies for the Sandia 100-meter blade.

    SciTech Connect

    Griffith, Daniel

    2013-11-01

    A series of design studies are performed to investigate the effects of advanced core materials and a new core material strategy on blade weight and performance for large blades using the Sandia 100-meter blade designs as a starting point. The initial core material design studies were based on the SNL100-01 100- meter carbon spar design. Advanced core material with improved performance to weight was investigated with the goal to reduce core material content in the design and reduce blade weight. A secondary element of the core study was to evaluate the suitability of core materials from natural, regrowable sources such as balsa and recyclable foam materials. The new core strategy for the SNL100-02 design resulted in a design mass of 59 tons, which is a 20% reduction from the most recent SNL100-01 carbon spar design and over 48% reduction from the initial SNL100-00 all-glass baseline blade. This document provides a description of the final SNL100-02 design, includes a description of the major design modifications, and summarizes the pertinent blade design information. This document is also intended to be a companion document to the distribution of the NuMAD blade model files for SNL100-02 that are made publicly available.

  10. Advanced Turbulence Modeling Concepts

    NASA Technical Reports Server (NTRS)

    Shih, Tsan-Hsing

    2005-01-01

    The ZCET program developed at NASA Glenn Research Center is to study hydrogen/air injection concepts for aircraft gas turbine engines that meet conventional gas turbine performance levels and provide low levels of harmful NOx emissions. A CFD study for ZCET program has been successfully carried out. It uses the most recently enhanced National combustion code (NCC) to perform CFD simulations for two configurations of hydrogen fuel injectors (GRC- and Sandia-injector). The results can be used to assist experimental studies to provide quick mixing, low emission and high performance fuel injector designs. The work started with the configuration of the single-hole injector. The computational models were taken from the experimental designs. For example, the GRC single-hole injector consists of one air tube (0.78 inches long and 0.265 inches in diameter) and two hydrogen tubes (0.3 inches long and 0.0226 inches in diameter opposed at 180 degree). The hydrogen tubes are located 0.3 inches upstream from the exit of the air element (the inlet location for the combustor). To do the simulation, the single-hole injector is connected to a combustor model (8.16 inches long and 0.5 inches in diameter). The inlet conditions for air and hydrogen elements are defined according to actual experimental designs. Two crossing jets of hydrogen/air are simulated in detail in the injector. The cold flow, reacting flow, flame temperature, combustor pressure and possible flashback phenomena are studied. Two grid resolutions of the numerical model have been adopted. The first computational grid contains 0.52 million elements, the second one contains over 1.3 million elements. The CFD results have shown only about 5% difference between the two grid resolutions. Therefore, the CFD result obtained from the model of 1.3-million grid resolution can be considered as a grid independent numerical solution. Turbulence models built in NCC are consolidated and well tested. They can handle both coarse and

  11. Advanced multistage turbine blade aerodynamics, performance, cooling, and heat transfer

    SciTech Connect

    Fleeter, S.; Lawless, P.B.

    1995-10-01

    The gas turbine has the potential for power production at the highest possible efficiency. The challenge is to ensure that gas turbines operate at the optimum efficiency so as to use the least fuel and produce minimum emissions. A key component to meeting this challenge is the turbine. Turbine performance, both aerodynamics and heat transfer, is one of the barrier advanced gas turbine development technologies. This is a result of the complex, highly three-dimensional and unsteady flow phenomena in the turbine. Improved turbine aerodynamic performance has been achieved with three-dimensional highly-loaded airfoil designs, accomplished utilizing Euler or Navier-Stokes Computational Fluid Dynamics (CFD) codes. These design codes consider steady flow through isolated blade rows. Thus they do not account for unsteady flow effects. However, unsteady flow effects have a significant impact on performance. Also, CFD codes predict the complete flow field. The experimental verification of these codes has traditionally been accomplished with point data - not corresponding plane field measurements. Thus, although advanced CFD predictions of the highly complex and three-dimensional turbine flow fields are available, corresponding data are not. To improve the design capability for high temperature turbines, a detailed understanding of the highly unsteady and three-dimensional flow through multi-stage turbines is necessary. Thus, unique data are required which quantify the unsteady three-dimensional flow through multi-stage turbine blade rows, including the effect of the film coolant flow. This requires experiments in appropriate research facilities in which complete flow field data, not only point measurements, are obtained and analyzed. Also, as design CFD codes do not account for unsteady flow effects, the next logical challenge and the current thrust in CFD code development is multiple-stage analyses that account for the interactions between neighboring blade rows.

  12. Recent advances in capacitance type of blade tip clearance measurements

    NASA Technical Reports Server (NTRS)

    Barranger, John P.

    1988-01-01

    Two recent electronic advances at NASA-Lewis that meet the blade tip clearance needs of a wide class of fans, compressors, and turbines are described. The first is a frequency modulated (FM) oscillator that requires only a single low cost ultrahigh frequency operational amplifier. Its carrier frequency is 42.8 MHz when used with a 61 cm long hermetically sealed coaxial cable. The oscillator can be calibrated in the static mode and has a negative peak frequency deviation of 400 kHz for a typical rotor blade. High temperature performance tests of the probe and 13 cm of the adjacent cable show good accuracy up to 600 C, the maximum which produces a clearance error of + or - 10 microns at a clearance of 500 microns. In the second advance, a guarded probe configuration allows a longer cable capacitance. The capacitance of the probe is part of a small time constant feedback in a high speed operational amplifier. The solution of the governing differential equation is applied to a ramp type of input. The results show an amplifier output that contains a term which is proportional to the derivative of the feedback capacitance. The capacitance is obtained by subtracting a balancing reference channel followed by an integration stage.

  13. Materials for advanced rocket engine turbopump turbine blades

    NASA Technical Reports Server (NTRS)

    Chandler, W. T.

    1985-01-01

    A study program was conducted to identify those materials that will provide the greatest benefits as turbine blades for advanced liquid propellant rocket engine turbines and to prepare technology plans for the development of those materials for use in the 1990 through 1995 period. The candidate materials were selected from six classes of materials: single-crystal (SC) superalloys, oxide dispersion-strengthened (ODS) superalloys, rapid solidification processed (RSP) superalloys, directionally solidified eutectic (DSE) superalloys, fiber-reinforced superalloy (FRS) composites, and ceramics. Properties of materials from the six classes were compiled and evaluated and property improvements were projected approximately 5 years into the future for advanced versions of materials in each of the six classes.

  14. Design and evaluation of low-cost laminated wood composite blades for intermediate size wind turbines: Blade design, fabrication concept, and cost analysis

    NASA Technical Reports Server (NTRS)

    Lieblein, S.; Gaugeon, M.; Thomas, G.; Zueck, M.

    1982-01-01

    As part of a program to reduce wind turbine costs, an evaluation was conducted of a laminated wood composite blade for the Mod-OA 200 kW wind turbine. The effort included the design and fabrication concept for the blade, together with cost and load analyses. The blade structure is composed of laminated Douglas fir veneers for the primary spar and nose sections, and honeycomb cored plywood panels for the trailing edges sections. The attachment of the wood blade to the rotor hub was through load takeoff studs bonded into the blade root. Tests were conducted on specimens of the key structural components to verify the feasibility of the concept. It is concluded that the proposed wood composite blade design and fabrication concept is suitable for Mod-OA size turbines (125-ft diameter rotor) at a cost that is very competitive with other methods of manufacture.

  15. Advanced Turbofan Duct Liner Concepts

    NASA Technical Reports Server (NTRS)

    Bielak, Gerald W.; Premo, John W.; Hersh, Alan S.

    1999-01-01

    The Advanced Subsonic Technology Noise Reduction Program goal is to reduce aircraft noise by 10 EPNdB by the year 2000 relative, to 1992 technology. The improvement goal for nacelle attenuation is 25% relative to 1992 technology by 1997 and 50% by 2000. The Advanced Turbofan Duct Liner Concepts Task work by Boeing presented in this document was in support of these goals. The basis for the technical approach was a Boeing study conducted in 1993-94 under NASA/FAA contract NAS1-19349, Task 6, investigating broadband acoustic liner concepts. As a result of this work, it was recommended that linear double layer, linear and perforate triple layer, parallel element, and bulk absorber liners be further investigated to improve nacelle attenuations. NASA LaRC also suggested that "adaptive" liner concepts that would allow "in-situ" acoustic impedance control also be considered. As a result, bias flow and high-temperature liner concepts were also added to the investigation. The major conclusion from the above studies is that improvements in nacelle liner average acoustic impedance characteristics alone will not result in 25% increased nacelle noise reduction relative to 1992 technology. Nacelle design advancements currently being developed by Boeing are expected to add 20-40% more acoustic lining to hardwall regions in current inlets, which is predicted to result in and additional 40-80% attenuation improvement. Similar advancements are expected to allow 10-30% more acoustic lining in current fan ducts with 10-30% more attenuation expected. In addition, Boeing is currently developing a scarf inlet concept which is expected to give an additional 40-80% attenuation improvement for equivalent lining areas.

  16. Advance finite element modeling of rotor blade aeroelasticity

    NASA Technical Reports Server (NTRS)

    Straub, F. K.; Sangha, K. B.; Panda, B.

    1994-01-01

    An advanced beam finite element has been developed for modeling rotor blade dynamics and aeroelasticity. This element is part of the Element Library of the Second Generation Comprehensive Helicopter Analysis System (2GCHAS). The element allows modeling of arbitrary rotor systems, including bearingless rotors. It accounts for moderately large elastic deflections, anisotropic properties, large frame motion for maneuver simulation, and allows for variable order shape functions. The effects of gravity, mechanically applied and aerodynamic loads are included. All kinematic quantities required to compute airloads are provided. In this paper, the fundamental assumptions and derivation of the element matrices are presented. Numerical results are shown to verify the formulation and illustrate several features of the element.

  17. NREL Advanced Research Turbine (ART) Aerodynamic Design of ART-2B Rotor Blades

    SciTech Connect

    Griffin, D.A.

    2000-09-05

    The National Renewable Energy Laboratory (NREL) installed two Advanced Research Turbines (ART) at the National Wind Technology Center near Boulder, Colorado, to use as full-scale test beds for ongoing research efforts, including three-dimensional blade aerodynamics and the effects of various control methods on turbine loads and performance. The Westinghouse WWG-0600 was selected as a baseline configuration for the ART turbines. The first turbine, ART-1, is currently operational and has been used to collect a baseline set of performance and loads data. A second turbine, ART-2A, incorporates several major modifications and may be upgraded further to a configuration designated aRT-2B. Possible features of the ART-2B turbine include a multi-degree of freedom hum and newly designed rotor blades. Global energy concepts, L.L.C. provided engineering support to NREL in designing the components for the ART-2B turbine. This document provides a summary of work performed by GEC on the aerodynamic design of ART-2B rotor blades.

  18. Preliminary Sizing of 120-Passenger Advanced Civil Rotorcraft Concepts

    NASA Technical Reports Server (NTRS)

    vanAken, Johannes M.; Sinsay, Jeffrey D.

    2006-01-01

    The results of a preliminary sizing study of advanced civil rotorcraft concepts that are capable of carrying 120 passengers over a range of 1,200 nautical miles are presented. The cruise altitude of these rotorcraft is 30,000 ft and the cruise velocity is 350 knots. The mission requires a hover capability, creating a runway independent solution, which might aid in reducing strain on the existing airport infrastructure. Concepts studied are a tiltrotor, a tandem rotor compound, and an advancing blade concept. The first objective of the study is to determine the relative merits of these designs in terms of mission gross weight, engine size, fuel weight, aircraft purchase price, and direct operating cost. The second objective is to identify the enabling technology for these advanced heavy lift civil rotorcraft.

  19. Improved blade profile loss and deviation angle models for advanced transonic compressor bladings. Part 1: A model for subsonic flow

    SciTech Connect

    Koenig, W.M.; Hennecke, D.K.; Fottner, L.

    1996-01-01

    New blading concepts as used in modern transonic axial-flow compressors require improved loss and deviation angle correlations. The new model presented in this paper incorporates several elements and treats blade-row flows having subsonic and supersonic inlet conditions separately. In the first part of this paper two proved and well-established profile loss correlations for subsonic flows are extended to quasi-two-dimensional conditions and to custom-tailored blade designs. Instead of a deviation angle correlation, a simple method based on singularities is utilized. The comparison between the new model and a recently published model demonstrates the improved accuracy in prediction of cascade performance achieved by the new model.

  20. Advanced nuclear thermal propulsion concepts

    NASA Technical Reports Server (NTRS)

    Howe, Steven D.

    1993-01-01

    In 1989, a Presidential directive created the Space Exploration Initiative (SEI) which had a goal of placing mankind on Mars in the early 21st century. The SEI was effectively terminated in 1992 with the election of a new administration. Although the initiative did not exist long enough to allow substantial technology development, it did provide a venue, for the first time in 20 years, to comprehensively evaluate advanced propulsion concepts which could enable fast, manned transits to Mars. As part of the SEI based investigations, scientists from NASA, DoE National Laboratories, universities, and industry met regularly and proceeded to examine a variety of innovative ideas. Most of the effort was directed toward developing a solid-core, nuclear thermal rocket and examining a high-power nuclear electric propulsion system. In addition, however, an Innovative Concepts committee was formed and charged with evaluating concepts that offered a much higher performance but were less technologically mature. The committee considered several concepts and eventually recommended that further work be performed in the areas of gas core fission rockets, inertial confinement fusion systems, antimatter based rockets, and gas core fission electric systems. Following the committee's recommendations, some computational modeling work has been performed at Los Alamos in certain of these areas and critical issues have been identified.

  1. NASA Institute for Advanced Concepts

    NASA Technical Reports Server (NTRS)

    Cassanova, Robert A.

    1999-01-01

    The purpose of NASA Institute for Advanced Concepts (NIAC) is to provide an independent, open forum for the external analysis and definition of space and aeronautics advanced concepts to complement the advanced concepts activities conducted within the NASA Enterprises. The NIAC will issue Calls for Proposals during each year of operation and will select revolutionary advanced concepts for grant or contract awards through a peer review process. Final selection of awards will be with the concurrence of NASA's Chief Technologist. The operation of the NIAC is reviewed biannually by the NIAC Science, Exploration and Technology Council (NSETC) whose members are drawn from the senior levels of industry and universities. The process of defining the technical scope of the initial Call for Proposals was begun with the NIAC "Grand Challenges" workshop conducted on May 21-22, 1998 in Columbia, Maryland. These "Grand Challenges" resulting from this workshop became the essence of the technical scope for the first Phase I Call for Proposals which was released on June 19, 1998 with a due date of July 31, 1998. The first Phase I Call for Proposals attracted 119 proposals. After a thorough peer review, prioritization by NIAC and technical concurrence by NASA, sixteen subgrants were awarded. The second Phase I Call for Proposals was released on November 23, 1998 with a due date of January 31, 1999. Sixty-three (63) proposals were received in response to this Call. On December 2-3, 1998, the NSETC met to review the progress and future plans of the NIAC. The next NSETC meeting is scheduled for August 5-6, 1999. The first Phase II Call for Proposals was released to the current Phase I grantees on February 3,1999 with a due date of May 31, 1999. Plans for the second year of the contract include a continuation of the sequence of Phase I and Phase II Calls for Proposals and hosting the first NIAC Annual Meeting and USRA/NIAC Technical Symposium in NASA HQ.

  2. Advanced fusion concepts: project summaries

    SciTech Connect

    1980-12-01

    This report contains descriptions of the activities of all the projects supported by the Advanced Fusion Concepts Branch of the Office of Fusion Energy, US Department of Energy. These descriptions are project summaries of each of the individual projects, and contain the following: title, principle investigators, funding levels, purpose, approach, progress, plans, milestones, graduate students, graduates, other professional staff, and recent publications. Information is given for each of the following programs: (1) reverse-field pinch, (2) compact toroid, (3) alternate fuel/multipoles, (4) stellarator/torsatron, (5) linear magnetic fusion, (6) liners, and (7) Tormac. (MOW)

  3. Design and evaluation of low-cost laminated-wood-composite blades for intermediate-size wind turbines: blade design, fabrication concept, and cost analysis

    SciTech Connect

    Lieblein, S.; Gougeon, M.; Thomas, G.; Zuteck, M.

    1982-11-01

    As part of a program to reduce wind turbine costs, an evaluation was conducted of a laminated wood composite blade for the Mod-OA 200-kW wind turbine. The effort included the design and fabrication concept for the blade, together with cost and load analyses. The blade structure is composed of laminated Douglas fir veneers for the primary spar and nose sections, and honeycomb cored plywood panels for the trailing edge sections. The attachment of the wood blade to the rotor hub was through load takeoff studs bonded into the blade root. Tests were conducted on specimens of the key structural components to verify the feasibility of the concept. Fabrication cost was estimated to be about 15,000 to 18,000 per blade in 1982 dollars for a production rate of 100 blades per year. The major conclusion of the investigation was that the proposed wood composite blade design and fabrication concept is suitable for Mod-OA size wind turbines (125-ft diameter rotor) at a cost that is very competitive with other methods of manufacture.

  4. A concept study of a carbon spar cap design for a 80m wind turbine blade

    NASA Astrophysics Data System (ADS)

    Rosemeier, M.; Bätge, M.

    2014-06-01

    The buckling resistance is a key design driver for large wind turbine blades with a significant influence on the material costs. During the structural design process the choice was made for carbon spar caps and two shear webs, which were set relatively far apart in order to stabilize the panels. This design presented a major challenge for the stability of the spar caps. The topology of these spar caps has been modified with regard to stability, comparing a continuous spar cap with split spar cap concepts and considering both lay-ups with hybrid carbon glass spar caps or sandwich concepts. Within those concepts, parametric studies were conducted varying different geometrical parameters of the spar caps and its layups. In order to determine the buckling resistance of the spar cap, an analytical model considering a 2D cross section discretized blade model was utilized to select the basic concept, after which a 3D numerical finite element model taking the whole blade into account was used to evaluate the chosen design concepts. The stability limit state analysis was conducted according to the certification scheme of GL guideline 2012. The various concepts were evaluated based on the blade's mass, tip deflection and modal properties. The results of this design process of the spar caps and the evaluation of the used analysis tools are presented within the paper.

  5. Computational fluid dynamics study of the variable-pitch split-blade fan concept

    NASA Technical Reports Server (NTRS)

    Kepler, C. E.; Elmquist, A. R.; Davis, R. L.

    1992-01-01

    A computational fluid dynamics study was conducted to evaluate the feasibility of the variable-pitch split-blade supersonic fan concept. This fan configuration was conceived as a means to enable a supersonic fan to switch from the supersonic through-flow type of operation at high speeds to a conventional fan with subsonic inflow and outflow at low speeds. During this off-design, low-speed mode of operation, the fan would operate with a substantial static pressure rise across the blade row like a conventional transonic fan; the front (variable-pitch) blade would be aligned with the incoming flow, and the aft blade would remain fixed in the position set by the supersonic design conditions. Because of these geometrical features, this low speed configuration would inherently have a large amount of turning and, thereby, would have the potential for a large total pressure increase in a single stage. Such a high-turning blade configuration is prone to flow separation; it was hoped that the channeling of the flow between the blades would act like a slotted wing and help alleviate this problem. A total of 20 blade configurations representing various supersonic and transonic configurations were evaluated using a Navier Stokes CFD program called ADAPTNS because of its adaptive grid features. The flow fields generated by this computational procedure were processed by another data reduction program which calculated average flow properties and simulated fan performance. These results were employed to make quantitative comparisons and evaluations of blade performance. The supersonic split-blade configurations generated performance comparable to a single-blade supersonic, through-flow fan configuration. Simulated rotor total pressure ratios of the order of 2.5 or better were achieved for Mach 2.0 inflow conditions. The corresponding fan efficiencies were approximately 75 percent or better. The transonic split-blade configurations having large amounts of turning were able to

  6. Cost analysis of advanced turbine blade manufacturing processes

    NASA Technical Reports Server (NTRS)

    Barth, C. F.; Blake, D. E.; Stelson, T. S.

    1977-01-01

    A rigorous analysis was conducted to estimate relative manufacturing costs for high technology gas turbine blades prepared by three candidate materials process systems. The manufacturing costs for the same turbine blade configuration of directionally solidified eutectic alloy, an oxide dispersion strengthened superalloy, and a fiber reinforced superalloy were compared on a relative basis to the costs of the same blade currently in production utilizing the directional solidification process. An analytical process cost model was developed to quantitatively perform the cost comparisons. The impact of individual process yield factors on costs was also assessed as well as effects of process parameters, raw materials, labor rates and consumable items.

  7. Aeroelastic behavior of composite helicopter rotor blades with advanced geometry tips

    SciTech Connect

    Friedmann, P.P.; Yuan, K.A.

    1995-12-31

    A new structural and aeroelastic model capable of representing the aeroelastic stability and response of composite helicopter rotor blades with advanced geometry tips is presented. Where it is understood that advanced geometry tips are blade tips having sweep, anhedral and taper in the outboard 10% segment of the blade. The blade is modeled by beam finite elements. A single element is used to represent the swept tip. The nonlinear equations of motion are derived using the Hamilton`s principle and are based on moderate deflection theory. Thus, the nonlinearities are of the geometric type. The important structural blade attributes captured by the model are arbitrary cross-sectional shape, general anisotropic material behavior, transverse shear and out-of-plane warping. The aerodynamic loads are based on quasi-steady Greenberg theory with reverse flow effects, using an implicit formulation. The nonlinear aeroelastic response of the blade is obtained from a fully coupled propulsive trim/aeroelastic response analysis. Aeroelastic stability is obtained from linearizing the equations of motion about the steady state response of the blade and using Floquet theory. Numerical results for the aeroelastic stability and response of a hingeless composite blade with two cell type cross section are presented, together with vibratory hub shears and moments. The influence of ply orientation and tip sweep is clearly illustrated by the results.

  8. Wind-tunnel evaluation of an advanced main-rotor blade design for a utility-class helicopter

    NASA Technical Reports Server (NTRS)

    Yeager, William T., Jr.; Mantay, Wayne R.; Wilbur, Matthew L.; Cramer, Robert G., Jr.; Singleton, Jeffrey D.

    1987-01-01

    An investigation was conducted in the Langley Transonic Dynamics Tunnel to evaluate differences between an existing utility-class main-rotor blade and an advanced-design main-rotor blade. The two rotor blade designs were compared with regard to rotor performance oscillatory pitch-link loads, and 4-per-rev vertical fixed-system loads. Tests were conducted in hover and over a range of simulated full-scale gross weights and density altitude conditions at advance ratios from 0.15 to 0.40. Results indicate that the advanced blade design offers performance improvements over the baseline blade in both hover and forward flight. Pitch-link oscillatory loads for the baseline rotor were more sensitive to the test conditions than those of the advanced rotor. The 4-per-rev vertical fixed-system load produced by the advanced blade was larger than that produced by the baseline blade at all test conditions.

  9. An improved CAMRAD model for aeroelastic stability analysis of the XV-15 with advanced technology blades

    NASA Technical Reports Server (NTRS)

    Acree, C. W., Jr.

    1993-01-01

    In pursuit of higher performance, the XV-15 Tiltrotor Research Aircraft was modified by the installation of new composite rotor blades. Initial flights with the Advanced Technology Blades (ATB's) revealed excessive rotor control loads that were traced to a dynamic mismatch between the blades and the aircraft control system. The analytical models of both the blades and the mechanical controls were extensively revised for use by the CAMRAD computer program to better predict aeroelastic stability and loads. This report documents the most important revisions and discusses their effects on aeroelastic stability predictions for airplane-mode flight. The ATB's may be flown in several different configurations for research, including changes in blade sweep and tip twist. The effects on stability of 1 deg and 0 deg sweep are illustrated, as are those of twisted and zero-twist tips. This report also discusses the effects of stiffening the rotor control system, which was done by locking out lateral cyclic swashplate motion with shims.

  10. Concept for Space Technology Advancement

    NASA Astrophysics Data System (ADS)

    Hansen, Jeremiah J.

    2005-02-01

    The space industry is based on an antiquated concept of disposable rockets, earth construction, and non-repairable satellites. Current space vehicle concepts hearken from a time of Cold War animosity and expeditiousness. Space systems are put together in small, single-purpose chunks that are launched with mighty, single-use rockets. Spacecraft need to change to a more versatile, capable, reusable, and mission efficient design. The Crew Exploration Vehicle (CEV) that President Bush put forward in his space initiative on Jan. 14, 2004 is a small first step. But like all first steps, the risk of eventual failure is great without a complementary set of steps, a reliable handhold, and a goal, which are outlined in this paper. The system for space access and development needs to be overhauled to allow for the access to space to complement the building in space, which promotes the production of goods in space, which enhances the exploitation of space resources… and the list goes on. Without supplemental and complementary infrastructure, all political, scientific, and idealistic endeavors to explore and exploit the near solar system will result in quagmires of failures and indecision. Renewed focus on fundamentals, integration, total-system consideration, and solid engineering can avoid catastrophe. Mission success, simple solutions, mission efficiency, and proper testing all seem to have been lost in the chase for the nickels and dimes. These items will increase capabilities available from a system or combination of systems. New propulsion options and materials will enable vehicles previously unachievable. Future spacecraft should exploit modular designs for repeatability and reduced cost. Space construction should use these modular systems on major components built in orbit. All vehicles should apply smart designs and monitoring systems for increased reliability and system awareness. Crew safety systems must use this awareness in alerting the crew, aiding collision

  11. Design aspects of the XV-15 advanced technology blade program

    NASA Technical Reports Server (NTRS)

    Smith, K. E.; Alexander, H. R.; Maisel, M. D.

    1985-01-01

    The paper discusses the design of a tiltrotor blade for application to the XV-15 research demonstration aircraft. The design features 43 deg nonlinear twist and nonuniform tapered planform. The structure is composite with extensive use of graphite in the primary structure. Instrumentation and wiring is encapsulated in the composite structure during the cure cycle. The tip shell is removable, providing access to the tracking and balance weights. This feature provides research facility of alternate tip configurations. The cuff is similarly removable. The graphite epoxy system used is high strain American Cyanamid's Celion 6000ST/Cycom 950. This is the first application of this material in rotor blades.

  12. Rotor blade vortex interaction noise

    NASA Astrophysics Data System (ADS)

    Yu, Yung H.

    2000-02-01

    Blade-vortex interaction noise-generated by helicopter main rotor blades is one of the most severe noise problems and is very important both in military applications and community acceptance of rotorcraft. Research over the decades has substantially improved physical understanding of noise-generating mechanisms, and various design concepts have been investigated to control noise radiation using advanced blade planform shapes and active blade control techniques. The important parameters to control rotor blade-vortex interaction noise and vibration have been identified: blade tip vortex structures and its trajectory, blade aeroelastic deformation, and airloads. Several blade tip design concepts have been investigated for diffusing tip vortices and also for reducing noise. However, these tip shapes have not been able to substantially reduce blade-vortex interaction noise without degradation of rotor performance. Meanwhile, blade root control techniques, such as higher-harmonic pitch control (HHC) and individual blade control (IBC) concepts, have been extensively investigated for noise and vibration reduction. The HHC technique has proved the substantial blade-vortex interaction noise reduction, up to 6 dB, while vibration and low-frequency noise have been increased. Tests with IBC techniques have shown the simultaneous reduction of rotor noise and vibratory loads with 2/rev pitch control inputs. Recently, active blade control concepts with smart structures have been investigated with the emphasis on active blade twist and trailing edge flap. Smart structures technologies are very promising, but further advancements are needed to meet all the requirements of rotorcraft applications in frequency, force, and displacement.

  13. Design of low noise wind turbine blades using Betz and Joukowski concepts

    NASA Astrophysics Data System (ADS)

    Shen, W. Z.; Hrgovan, I.; Okulov, V.; Zhu, W. J.; Madsen, J.

    2014-06-01

    This paper presents the aerodynamic design of low noise wind turbine blades using Betz and Joukowski concepts. The aerodynamic model is based on Blade Element Momentum theory whereas the aeroacoustic prediction model is based on the BPM model. The investigation is started with a 3MW baseline/reference turbine rotor with a diameter of 80 m. To reduce the noise emission from the baseline rotor, the rotor is reconstructed with the low noise CQU-DTU-LN1 series of airfoils which has been tested in the acoustic wind tunnel located at Virginia Tech. Finally, 3MW low noise turbine rotors are designed using the concepts of Betz and Joukowski, and the CQU-DTU-LN1 series of airfoils. Performance analysis shows that the newly designed turbine rotors can achieve an overall noise reduction of 6 dB and 1.5 dB(A) with a similar power output as compared to the reference rotor.

  14. Advanced cooled-engine shell/spar turbine vanes and blades. Final report

    SciTech Connect

    Not Available

    1986-08-01

    The objectives of the Advanced Cooling Full-Scale Engine Demonstration Program, Phase II (EPRI Contract RP1319-5), were to develop and to demonstrate an advanced aircraft cooling technology for use in the vanes, blades, and associated hot-section components of a utility-sized combustion turbine. Use of such technology would provide reduced metal-surface temperatures for improved reliability or the potential for increasing turbine inlet temperatures for improved thermal efficiency. In the shell/spar cooling technology chosen for the vane and blade construction, cooling air flows through channels between a thin metal external sheet (shell) and a hollow-cast internal support member (spar). The shell and spar are joined by diffusion bonding. The results of first-stage shell/spar blade and vane design studies are reported, and heat transfer and stress analyses of the blade and vane designs are featured. The progress made on the development of the vane fabrication technology, up to the early termination at the end of 1984, is fully delineated. The successful development of an ultrasonic inspection technique to indicate unbonded areas between the shell and spar is reported. The results of heat transfer testing with shell/spar specimens and low-cycle fatigue testing of IN617 sheet are described. Problem areas in the determination of the low-cycle fatigue life expectancy of the designs are identified. Recommendations are given for continuing the blade and vane shell/spar advanced cooling technology development.

  15. Advanced Concepts: Aneutronic Fusion Power and Propulsion

    NASA Technical Reports Server (NTRS)

    Chapman, John J.

    2012-01-01

    Aneutronic Fusion for In-Space thrust, power. Clean energy & potential nuclear gains. Fusion plant concepts, potential to use advanced fuels. Methods to harness ionic momentum for high Isp thrust plus direct power conversion into electricity will be presented.

  16. Large-scale Advanced Prop-fan (LAP) hub/blade retention design report

    NASA Technical Reports Server (NTRS)

    Soule, Matthew

    1986-01-01

    The Large-scale Advanced Prop-fan (LAP) hub assembly forms a semi-rigid link between the blades, which provide the thrust, and the engine shaft, which provides the torque. The hub and tailshaft is a one piece partially forged part which is carburized, heat treated and machined. A single row ball bearing restrains each of the eight blades in the hub, while the tailshaft secures the propeller to the engine shaft with two cone seats that are preloaded against each other by the Prop-fan retaining nut. The hub also forms the support for the pitch change actuator system, the control and the spinner. The retention transmits the loads from the blades to the hub while allowing the changes in blade pitch. The single row ball bearing retention provides ease of maintenance by allowing individual blade replacement without dissassembly of the hub. It has a through hardened inner race which seats against the aluminum blade shank and an outer race which is integral with the barrel. The outer race area is carburized to achieve the hardness necessary to support the ball loads. The balls are kept from contact with each other by a separator. The rotational speed of the propeller keeps the retention submerged in the oil which is contained in the hub by a seal. Stress and strain analysis, material hardness requirements, weight predictions, and stiffness characteristics are discussed.

  17. Advanced instrumentation concepts for environmental control subsystems

    NASA Technical Reports Server (NTRS)

    Yang, P. Y.; Schubert, F. H.; Gyorki, J. R.; Wynveen, R. A.

    1978-01-01

    Design, evaluation and demonstration of advanced instrumentation concepts for improving performance of manned spacecraft environmental control and life support systems were successfully completed. Concepts to aid maintenance following fault detection and isolation were defined. A computer-guided fault correction instruction program was developed and demonstrated in a packaged unit which also contains the operator/system interface.

  18. Advanced Concepts in Quantum Mechanics

    NASA Astrophysics Data System (ADS)

    Esposito, Giampiero; Marmo, Giuseppe; Miele, Gennaro; Sudarshan, George

    2014-11-01

    Preface; 1. Introduction: the need for a quantum theory; 2. Experimental foundations of quantum theory; 3. Waves and particles; 4. Schrödinger picture, Heisenberg picture and probabilistic aspects; 5. Integrating the equations of motion; 6. Elementary applications: 1-dimensional problems; 7. Elementary applications: multidimensional problems; 8. Coherent states and related formalism; 9. Introduction to spin; 10. Symmetries in quantum mechanics; 11. Approximation methods; 12. Modern pictures of quantum mechanics; 13. Formulations of quantum mechanics and their physical implications; 14. Exam problems; Glossary of geometric concepts; References; Index.

  19. Advanced concepts in knee arthrodesis

    PubMed Central

    Wood, Jennifer H; Conway, Janet D

    2015-01-01

    The aim is to describe advanced strategies that can be used to diagnose and treat complications after knee arthrodesis and to describe temporary knee arthrodesis to treat infected knee arthroplasty. Potential difficult complications include nonunited knee arthrodesis, limb length discrepancy after knee arthrodesis, and united but infected knee arthrodesis. If a nonunited knee arthrodesis shows evidence of implant loosening or failure, then bone grafting the nonunion site as well as exchange intramedullary nailing and/or supplemental plate fixation are recommended. If symptomatic limb length discrepancy cannot be satisfactorily treated with a shoe lift, then the patient should undergo tibial lengthening over nail with a monolateral fixator or exchange nailing with a femoral internal lengthening device. If a united knee arthrodesis is infected, the nail must be removed. Then the surgeon has the option of replacing it with a long, antibiotic cement-coated nail. The authors also describe temporary knee arthrodesis for infected knee arthroplasty in patients who have the potential to undergo insertion of a new implant. The procedure has two goals: eradication of infection and stabilization of the knee. A temporary knee fusion can be accomplished by inserting both an antibiotic cement-coated knee fusion nail and a static antibiotic cement-coated spacer. These advanced techniques can be helpful when treating difficult complications after knee arthrodesis and treating cases of infected knee arthroplasty. PMID:25793160

  20. Investigation of Advanced Processed Single-Crystal Turbine Blade Alloys

    NASA Technical Reports Server (NTRS)

    Peters, B. J.; Biondo, C. M.; DeLuca, D. P.

    1995-01-01

    This investigation studied the influence of thermal processing and microstructure on the mechanical properties of the single-crystal, nickel-based superalloys PWA 1482 and PWA 1484. The objective of the program was to develop an improved single-crystal turbine blade alloy that is specifically tailored for use in hydrogen fueled rocket engine turbopumps. High-gradient casting, hot isostatic pressing (HIP), and alternate heat treatment (HT) processing parameters were developed to produce pore-free, eutectic-free microstructures with different (gamma)' precipitate morphologies. Test materials were cast in high thermal gradient solidification (greater than 30 C/cm (137 F/in.)) casting furnaces for reduced dendrite arm spacing, improved chemical homogeneity, and reduced interdendritic pore size. The HIP processing was conducted in 40 cm (15.7 in.) diameter production furnaces using a set of parameters selected from a trial matrix study. Metallography was conducted on test samples taken from each respective trial run to characterize the as-HIP microstructure. Post-HIP alternate HT processes were developed for each of the two alloys. The goal of the alternate HT processing was to fully solution the eutectic gamma/(gamma)' phase islands and to develop a series of modified (gamma)' morphologies for subsequent characterization testing. This was accomplished by slow cooling through the (gamma)' solvus at controlled rates to precipitate volume fractions of large (gamma)'. Post-solution alternate HT parameters were established for each alloy providing additional volume fractions of finer precipitates. Screening tests included tensile, high-cycle fatigue (HCF), smooth and notched low-cycle fatigue (LCF), creep, and fatigue crack growth evaluations performed in air and high pressure (34.5 MPa (5 ksi)) hydrogen at room and elevated temperature. Under the most severe embrittling conditions (HCF and smooth and notched LCF in 34.5 MPa (5 ksi) hydrogen at 20 C (68 F), screening test

  1. Prediction of Unsteady Blade Surface Pressures on an Advanced Propeller at an Angle of Attack

    NASA Technical Reports Server (NTRS)

    Nallasamy, M.; Groeneweg, J. F.

    1989-01-01

    The numerical solution of the unsteady, three-dimensional, Euler equations is considered in order to obtain the blade surface pressures of an advanced propeller at an angle of attack. The specific configuration considered is the SR7L propeller at cruise conditions with a 4.6 deg inflow angle corresponding to the plus 2 deg nacelle tilt of the Propeller Test Assessment (PTA) flight test condition. The results indicate nearly sinusoidal response of the blade loading, with angle of attack. For the first time, detailed variations of the chordwise loading as a function of azimuthal angle are presented. It is observed that the blade is lightly loaded for part of the revolution and shocks appear from hub to about 80 percent radial station for the highly loaded portion of the revolution.

  2. Prediction of unsteady blade surface pressures on an advanced propeller at an angle of attack

    NASA Technical Reports Server (NTRS)

    Nallasamy, M.; Groeneweg, J. F.

    1989-01-01

    The paper considers the numerical solution of the unsteady, three-dimensional, Euler equations to obtain the blade surface pressures of an advanced propeller at an angle of attack. The specific configuration considered is the SR7L propeller at cruise conditions with a 4.6 deg inflow angle corresponding to the +2 deg nacelle tilt of the Propeller Test Assessment (PTA) flight test condition. The results indicate nearly sinusoidal response of the blade loading, with angle of attack. For the first time, detailed variations of the chordwise loading as a function of azimuthal angle are presented. It is observed that the blade is lightly loaded for part of the revolution and shocks appear from hub to about 80 percent radial station for the highly loaded portion of the revolution.

  3. Advanced Accelerator Concepts Final Report

    SciTech Connect

    Wurtele, Jonathan S.

    2014-05-13

    A major focus of research supported by this Grant has been on the ALPHA antihydrogen trap. We first trapped antihydrogen in 2010 and soon thereafter demonstrated trapping for 1000s. We now have observed resonant quantum interactions with antihydrogen. These papers in Nature and Nature Physics report the major milestones in anti-atom trapping. The success was only achieved through careful work that advanced our understanding of collective dynamics in charged particle systems, the development of new cooling and diagnostics, and in- novation in understanding how to make physics measurements with small numbers of anti-atoms. This research included evaporative cooling, autoresonant excitation of longitudinal motion, and centrifugal separation. Antihydrogen trapping by ALPHA is progressing towards the point when a important theories believed by most to hold for all physical systems, such as CPT (Charge-Parity-Time) invariance and the Weak Equivalence Principle (matter and antimatter behaving the same way under the influence of gravity) can be directly tested in a new regime. One motivation for this test is that most accepted theories of the Big Bang predict that we should observe equal amounts of matter and antimatter. However astrophysicists have found very little antimatter in the universe. Our experiment will, if successful over the next seven years, provide a new test of these ideas. Many earlier detailed and beautiful tests have been made, but the trapping of neutral antimatter allows us to explore the possibility of direct, model-independent tests. Successful cooling of the anti atoms, careful limits on systematics and increased trapping rates, all planned for our follow-up experiment (ALPHA-II) will reach unrivaled precision. CPT invariance implies that the spectra of hydrogen and antihydrogen should be identical. Spectra can be measured in principle with great precision, and any di erences we might observe would revolutionize fundamental physics. This is the

  4. Review of status and potential of tungsten-wire: Superalloy composites for advanced gas turbine engine blades

    NASA Technical Reports Server (NTRS)

    Signorelli, R. A.

    1972-01-01

    The current status of development of refractory-wire-superalloy composites and the potential for their application to turbine blades in land-based power generation and advanced aircraft engines are reviewed. The data indicate that refractory-wire-superalloy composites have application as turbine blades at temperatures of 2200 F and above.

  5. 76 FR 62678 - Table Saw Blade Contact Injuries; Advance Notice of Proposed Rulemaking; Request for Comments and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-11

    ... accidental contact with the blade. In the Federal Register of July 9, 2003 (68 FR 40912) and September 5, 2003 (68 FR 52753), we invited comments on the issues raised by the petition (Petition No. CP03-2). We... COMMISSION 16 CFR Chapter II Table Saw Blade Contact Injuries; Advance Notice of Proposed Rulemaking;...

  6. Demonstration of an elastically coupled twist control concept for tilt rotor blade application

    NASA Technical Reports Server (NTRS)

    Lake, R. C.; Nixon, M. W.; Wilbur, M. L.; Singleton, J. D.; Mirick, P. H.

    1994-01-01

    This study demonstrated the feasibility of passive blade twist control for composite rotor blades. Hover testing of the set of blades produced maximum twist changes of 2.54 degrees for the unballasted blade configuration and 5.24 degrees for the ballasted blade configuration. These results compared well with those obtained from a detailed finite element analysis model of the rotor blade, which yielded maximum twists of 3.02 and 5.61 degrees for the unballasted and ballasted blade configurations, respectively.

  7. Advanced Vehicle system concepts. [nonpetroleum passenger transportation

    NASA Technical Reports Server (NTRS)

    Hardy, K. S.; Langendoen, J. M.

    1983-01-01

    Various nonpetroleum vehicle system concepts for passenger vehicles in the 1990's are being considered as part of the Advanced Vehicle (AV) Assessment at the Jet Propulsion Laboratory. The vehicle system and subsystem performance requirements, the projected characteristics of mature subsystem candidates, and promising systems are presented. The system candidates include electric and hybrid vehicles powered by electricity with or without a nonpetroleum power source. The subsystem candidates include batteries (aqueous-mobile, flow, high-temperature, and metal-air), fuel cells (phosphoric acid, advanced acids, and solid polymer electrolyte), nonpetroleum heat engines, advanced dc and ac propulsion components, power-peaking devices, and transmissions.

  8. Stress analysis of advanced attack helicopter composite main rotor blade root end lug

    NASA Technical Reports Server (NTRS)

    Baker, D. J.

    1982-01-01

    Stress analysis of the Advanced Attack Helicopter (AAH) composite main rotor blade root end lug is described. The stress concentration factor determined from a finite element analysis is compared to an empirical value used in the lug design. The analysis and test data indicate that the stress concentration is primarily a function of configuration and independent of the range of material properties typical of Kevlar-49/epoxy and glass epoxy.

  9. Proposed research on advanced accelerator concepts

    SciTech Connect

    Davidson, R.C.; Wurtele, J.S.

    1991-09-01

    This report summarizes technical progress and accomplishments during the proposed three-year research on advanced accelerator concepts supported by the Department of Energy under Contract No. DE-FG02-88ER40465. A vigorous theoretical program has been pursued in critical problem areas related to advanced accelerator concepts and the basic equilibrium, stability, and radiation properties of intense charged particle beams. Broadly speaking, our research has made significant contributions in the following three major areas: Investigations of physics issues related to particle acceleration including two-beam accelerators and cyclotron resonance laser (CRL) accelerators; Investigations of RF sources including the free- electron lasers, cyclotron resonance masers, and relativistic magnetrons; Studies of coherent structures in electron plasmas and beams ranging from a low-density, nonrelativistic, pure electron plasma column to high-density, relativistic, non-neutral electron flow in a high-voltage diode. The remainder of this report presents theoretical and computational advances in these areas.

  10. Field testing of linear individual pitch control on the two-bladed controls advanced research turbine

    SciTech Connect

    van Solingen, Edwin; Fleming, Paul A.; Scholbrock, Andrew; van Wingerden, Jan-Willem

    2015-04-17

    This paper presents the results of field tests using linear individual pitch control (LIPC) on the two-bladed Controls Advanced Research Turbine 2 (CART2) at the National Renewable Energy Laboratory (NREL). LIPC has recently been introduced as an alternative to the conventional individual pitch control (IPC) strategy for two-bladed wind turbines. The main advantage of LIPC over conventional IPC is that it requires, at most, only two feedback loops to potentially reduce the periodic blade loads. In previous work, LIPC was designed to implement blade pitch angles at a fixed frequency (e.g., the once-per-revolution (1P) frequency), which made it only applicable in above-rated wind turbine operating conditions. In this study, LIPC is extended to below-rated operating conditions by gain scheduling the controller on the rotor speed. With this extension, LIPC and conventional IPC are successfully applied to the NREL CART2 wind turbine. Lastly, the field-test results obtained during the measurement campaign indicate that LIPC significantly reduces the wind turbine loads for both below-rated and above-rated operation.

  11. Field testing of linear individual pitch control on the two-bladed controls advanced research turbine

    DOE PAGESBeta

    van Solingen, Edwin; Fleming, Paul A.; Scholbrock, Andrew; van Wingerden, Jan-Willem

    2015-04-17

    This paper presents the results of field tests using linear individual pitch control (LIPC) on the two-bladed Controls Advanced Research Turbine 2 (CART2) at the National Renewable Energy Laboratory (NREL). LIPC has recently been introduced as an alternative to the conventional individual pitch control (IPC) strategy for two-bladed wind turbines. The main advantage of LIPC over conventional IPC is that it requires, at most, only two feedback loops to potentially reduce the periodic blade loads. In previous work, LIPC was designed to implement blade pitch angles at a fixed frequency (e.g., the once-per-revolution (1P) frequency), which made it only applicablemore » in above-rated wind turbine operating conditions. In this study, LIPC is extended to below-rated operating conditions by gain scheduling the controller on the rotor speed. With this extension, LIPC and conventional IPC are successfully applied to the NREL CART2 wind turbine. Lastly, the field-test results obtained during the measurement campaign indicate that LIPC significantly reduces the wind turbine loads for both below-rated and above-rated operation.« less

  12. The development of advanced technology blades for tilt-rotor aircraft

    NASA Technical Reports Server (NTRS)

    Alexander, Harold R.; Maisel, Martin D.; Giulianetti, Demo J.

    1986-01-01

    The paper discusses the development and ground testing of blades for the XV-15 tilt-rotor demonstrator aircraft. This work was performed under contract NAS2-11250 with NASA Ames Research Center. These blades, known as the Advanced Technology Blades (ATB), replace the rectangular, steel blades which were part of the XV-15 original design. The materials used in the primary structure of the ATB are fiberglass and high strain graphite epoxy laminates. This facilitates the use of 43 deg of nonlinear twist, a nonuniform tapered planform and thin airfoils required for aerodynamic efficiency. Instrumentation life is extended by encapsulating gages and wiring in the composite structure. Tip shells and cuff fairings are removable to provide access to tip weights and retention hardware; they are also replaceable with alternate research configurations. Extensive laboratory testing has validated predicted strength characteristics. Hover testing has demonstrated performance significantly superior to that predicted by contemporary methodology. Key elements of the test rig used for rotor performance measurement were developed as an ancillary part of the present program. The performance testing included measurement of near- and far-field noise. Induced inflow velocity distributions were also determined and photographs of tip vortex condensation trails were taken. These are providing guidance for modifications to hover peformance codes.

  13. ADVANCED HIGH PERFORMANCE SOLID WALL BLANKET CONCEPTS

    SciTech Connect

    WONG, CPC; MALANG, S; NISHIO, S; RAFFRAY, R; SAGARA, S

    2002-04-01

    OAK A271 ADVANCED HIGH PERFORMANCE SOLID WALL BLANKET CONCEPTS. First wall and blanket (FW/blanket) design is a crucial element in the performance and acceptance of a fusion power plant. High temperature structural and breeding materials are needed for high thermal performance. A suitable combination of structural design with the selected materials is necessary for D-T fuel sufficiency. Whenever possible, low afterheat, low chemical reactivity and low activation materials are desired to achieve passive safety and minimize the amount of high-level waste. Of course the selected fusion FW/blanket design will have to match the operational scenarios of high performance plasma. The key characteristics of eight advanced high performance FW/blanket concepts are presented in this paper. Design configurations, performance characteristics, unique advantages and issues are summarized. All reviewed designs can satisfy most of the necessary design goals. For further development, in concert with the advancement in plasma control and scrape off layer physics, additional emphasis will be needed in the areas of first wall coating material selection, design of plasma stabilization coils, consideration of reactor startup and transient events. To validate the projected performance of the advanced FW/blanket concepts the critical element is the need for 14 MeV neutron irradiation facilities for the generation of necessary engineering design data and the prediction of FW/blanket components lifetime and availability.

  14. Boeing EX Concept, Advanced Surveillance Aircraft

    NASA Technical Reports Server (NTRS)

    1993-01-01

    The photograph shows a model of the Boeing EX Concept installed in the NASA Langley 16 foot Transonic Tunnel. The Boeing EX is an advanced surveillance aircraft proposed by Boeing to replace the Grumman E-2C Hawkeye. The concept employs the diamond-shape 'joined-wing'planform and active aperture radar arrays in each wing segment to create a more aerodynamic effective surveillance aircraft. Wind tunnel testing was conducted to evaulate longitudinal and lateral aerodynamic charcteristics and the effectiveness of control surface deflections. Measurements were made to determine the effects of the wings and fuselage on the inlet fan face total pressure distortions at angle of attack and sideslip.

  15. Research Opportunities in Advanced Aerospace Concepts

    NASA Technical Reports Server (NTRS)

    Jones, Gregory S.; Bangert, Linda S.; Garber, Donald P.; Huebner, Lawrence D.; McKinley, Robert E.; Sutton, Kenneth; Swanson, Roy C., Jr.; Weinstein, Leonard

    2000-01-01

    This report is a review of a team effort that focuses on advanced aerospace concepts of the 21st Century. The paper emphasis advanced technologies, rather than cataloging every unusual aircraft that has ever been attempted. To dispel the myth that "aerodynamics is a mature science" an extensive list of "What we cannot do, or do not know" was enumerated. A zeit geist, a feeling for the spirit of the times, was developed, based on existing research goals. Technological drivers and the constraints that might influence these technological developments in a future society were also examined. The present status of aeronautics, space exploration, and non-aerospace applications, both military and commercial, including enabling technologies are discussed. A discussion of non-technological issues affecting advanced concepts research is presented. The benefit of using the study of advanced vehicles as a tool to uncover new directions for technology development is often necessary. An appendix is provided containing examples of advanced vehicle configurations currently of interest.

  16. ADVANCED COMPOSITE WIND TURBINE BLADE DESIGN BASED ON DURABILITY AND DAMAGE TOLERANCE

    SciTech Connect

    Galib Abumeri; Frank Abdi

    2012-02-16

    The objective of the program was to demonstrate and verify Certification-by-Analysis (CBA) capability for wind turbine blades made from advanced lightweight composite materials. The approach integrated durability and damage tolerance analysis with robust design and virtual testing capabilities to deliver superior, durable, low weight, low cost, long life, and reliable wind blade design. The GENOA durability and life prediction software suite was be used as the primary simulation tool. First, a micromechanics-based computational approach was used to assess the durability of composite laminates with ply drop features commonly used in wind turbine applications. Ply drops occur in composite joints and closures of wind turbine blades to reduce skin thicknesses along the blade span. They increase localized stress concentration, which may cause premature delamination failure in composite and reduced fatigue service life. Durability and damage tolerance (D&DT) were evaluated utilizing a multi-scale micro-macro progressive failure analysis (PFA) technique. PFA is finite element based and is capable of detecting all stages of material damage including initiation and propagation of delamination. It assesses multiple failure criteria and includes the effects of manufacturing anomalies (i.e., void, fiber waviness). Two different approaches have been used within PFA. The first approach is Virtual Crack Closure Technique (VCCT) PFA while the second one is strength-based. Constituent stiffness and strength properties for glass and carbon based material systems were reverse engineered for use in D&DT evaluation of coupons with ply drops under static loading. Lamina and laminate properties calculated using manufacturing and composite architecture details matched closely published test data. Similarly, resin properties were determined for fatigue life calculation. The simulation not only reproduced static strength and fatigue life as observed in the test, it also showed composite

  17. Advanced avionics concepts: Autonomous spacecraft control

    NASA Technical Reports Server (NTRS)

    1990-01-01

    A large increase in space operations activities is expected because of Space Station Freedom (SSF) and long range Lunar base missions and Mars exploration. Space operations will also increase as a result of space commercialization (especially the increase in satellite networks). It is anticipated that the level of satellite servicing operations will grow tenfold from the current level within the next 20 years. This growth can be sustained only if the cost effectiveness of space operations is improved. Cost effectiveness is operational efficiency with proper effectiveness. A concept is presented of advanced avionics, autonomous spacecraft control, that will enable the desired growth, as well as maintain the cost effectiveness (operational efficiency) in satellite servicing operations. The concept of advanced avionics that allows autonomous spacecraft control is described along with a brief description of each component. Some of the benefits of autonomous operations are also described. A technology utilization breakdown is provided in terms of applications.

  18. Unsteady blade surface pressures on a large-scale advanced propeller - Prediction and data

    NASA Technical Reports Server (NTRS)

    Nallasamy, M.; Groeneweg, J. F.

    1990-01-01

    An unsteady three dimensional Euler analysis technique is employed to compute the flowfield of an advanced propeller operating at an angle of attack. The predicted blade pressure waveforms are compared with wind tunnel data at two Mach numbers, 0.5 and 0.2. The inflow angle is three degrees. For an inflow Mach number of 0.5, the predicted pressure response is in fair agreement with data: the predicted phases of the waveforms are in close agreement with data while the magnitudes are underpredicted. At the low Mach number of 0.2 (take-off) the numerical solution shows the formation of a leading edge vortex which is in qualitative agreement with measurements. However, the highly nonlinear pressure response measured on the blade suction surface is not captured in the present inviscid analysis.

  19. Unsteady blade-surface pressures on a large-scale advanced propeller: Prediction and data

    NASA Technical Reports Server (NTRS)

    Nallasamy, M.; Groeneweg, J. F.

    1990-01-01

    An unsteady 3-D Euler analysis technique is employed to compute the flow field of an advanced propeller operating at an angle of attack. The predicted blade pressure waveforms are compared with wind tunnel data at two Mach numbers, 0.5 and 0.2. The inflow angle is three degrees. For an inflow Mach number of 0.5, the predicted pressure response is in fair agreement with data: the predicted phases of the waveforms are in close agreement with data while the magnitudes are underpredicted. At the low Mach number of 0.2 (takeoff), the numerical solution shows the formation of a leading edge vortex which is in qualitative agreement with measurements. However, the highly nonlinear pressure response measured on the blade suction surface is not captured in the present inviscid analysis.

  20. Advanced turboprop wing installation effects measured by unsteady blade pressure and noise

    NASA Technical Reports Server (NTRS)

    Heidelberg, Laurence J.; Woodward, Richard P.

    1987-01-01

    A single rotation model propeller (SR-7A) was tested at simulated takeoff/approach conditions (Mach 0.2), in the NASA Lewis 9- by 15-Ft Anechoic Wind Tunnel. Both unsteady blade surface pressures and noise measurements were made for a tractor configuration with propeller/straight wing and propeller alone configurations. The angle between the wing chord and propeller axis (droop angle) was varied along with the wing angle of attack to determine the effects on noise and unsteady loading. A method was developed that uses unsteady blade pressure measurements to provide a quantitative indication of propeller inflow conditions, at least for a uniform (across the propeller disk) inflow angle. The wing installation caused a nearly uniform upwash at the propeller inlet as evidenced by the domination of the pressure spectra by the first shaft order. This inflow angle increased at a rate of almost 150 percent of that of the wing angle-of-attack for a propeller-wing spacing of 0.54 wing chords at a constant droop angle. The flyover noise, as measured by the maximum blade passing frequency level, correlates closely with the propeller inflow angle (approx. 0.6 dB per degree of inflow angle) for all droop angles and wing angles of attack tested, including the propeller alone data. Large changes in the unsteady pressure responses on the suction surface of the blade were observed as the advance ratio was varied. The presence of a leading edge vortex may explain this behavior since changes in the location of this vortex would change with loading (advance ratio).

  1. Advances in Ceramic Matrix Composite Blade Damping Characteristics for Aerospace Turbomachinery Applications

    NASA Technical Reports Server (NTRS)

    Min, James B.; Harris, Donald L.; Ting, J. M.

    2011-01-01

    For advanced aerospace propulsion systems, development of ceramic matrix composite integrally-bladed turbine disk technology is attractive for a number of reasons. The high strength-to-weight ratio of ceramic composites helps to reduce engine weight and the one-piece construction of a blisk will result in fewer parts count, which should translate into reduced operational costs. One shortcoming with blisk construction, however, is that blisks may be prone to high cycle fatigue due to their structural response to high vibration environments. Use of ceramic composites is expected to provide some internal damping to reduce the vibratory stresses encountered due to unsteady flow loads through the bladed turbine regions. A goal of our research was to characterize the vibration viscous damping behavior of C/SiC composites. The vibration damping properties were measured and calculated. Damping appeared to decrease with an increase in the natural frequency. While the critical damping amount of approximately 2% is required for typical aerospace turbomachinery engines, the C/SiC damping at high frequencies was less than 0.2% from our study. The advanced high-performance aerospace propulsion systems almost certainly will require even more damping than what current vehicles require. A purpose of this paper is to review some work on C/SiC vibration damping by the authors for the NASA CMC turbine blisk development program and address an importance of the further investigation of the blade vibration damping characteristics on candidate CMC materials for the NASA s advanced aerospace turbomachinery engine systems.

  2. Fish Passage Assessment of an Advanced Hydropower Turbine and Conventional Turbine Using Blade-strike Modeling

    SciTech Connect

    Deng, Zhiqun; Carlson, Thomas J.; Dauble, Dennis D.; Ploskey, Gene R.

    2011-01-04

    In the Columbia and Snake River basins, several species of Pacific salmon were listed under the Endangered Species Act of 1973 due to significant declines of fish population. Dam operators and design engineers are thus faced with the task of making those hydroelectric facilities more ecologically friendly through changes in hydro-turbine design and operation. Public Utility District No. 2 of Grant County, Washington, applied for re-licensing from the U.S. Federal Energy Regulatory Commission to replace the 10 turbines at Wanapum Dam with advanced hydropower turbines that were designed to increase power generation and improve fish passage conditions. We applied both deterministic and stochastic blade-strike models to the newly installed turbine and an existing turbine. Modeled probabilities were compared to the results of a large-scale live fish survival study and a sensor fish study under the same operational parameters. Overall, injury rates predicted by the deterministic model were higher than experimental rates of injury while those predicted by the stochastic model were in close agreement with experiment results. Fish orientation at the time of entry into the plane of the leading edges of the turbine runner blades was an important factor contributing to uncertainty in modeled results. The advanced design turbine had slightly higher modeled injury rates than the existing turbine design; however, there was no statistical evidence that suggested significant differences in blade-strike injuries between the two turbines and the hypothesis that direct fish survival rate through the advanced hydropower turbine is equal or better than that through the conventional turbine could not be rejected.

  3. Far-field hover acoustic characteristics of the XV-15 tiltrotor aircraft with Advanced Technology Blades

    NASA Astrophysics Data System (ADS)

    Conner, David A.; Wellman, Brent

    1991-05-01

    An experimental investigation has been conducted with the XV-15 tilt-rotor VTOL aircraft in order to ascertain the noise-reduction efficacy of Advanced Technology Blades (ATBs). Attention is given to acoustic directivity characteristics in the lower hemisphere of the sound field. Modest overall sound pressure levels (OASPLs) were measured near the in-plane position, showing that thickness noise is not significant in hover when ATBs are used; rotor tip-speed reductions reduced the average OASPL by nearly 8 dB in-plane and by nearly 5 dB at 12.6 deg below the rotor plane.

  4. High-pressure hydrogen testing of single crystal superalloys for advanced rocket engine turbopump turbine blades

    NASA Technical Reports Server (NTRS)

    Alter, W. S.; Parr, R. A.; Johnston, M. H.; Strizak, J. P.

    1984-01-01

    A screening program to determine the effects of high pressure hydrogen on selected candidate materials for advanced single crystal turbine blade applications is examined. The alloys chosen for the investigation are CM SX-2, CM SX-4C, Rene N-4, and PWA1480. Testing is carried out in hydrogen and helium at 34 MPa and room temperature, with both notched and unnotched single crystal specimens. Results show a significant variation in susceptibility to Hydrogen Environment Embrittlement (HEE) among the four alloys and a marked difference in fracture topography between hydrogen and helium environment specimens.

  5. Outlook for advanced concepts in transport aircraft

    NASA Technical Reports Server (NTRS)

    Conner, D. W.

    1980-01-01

    Air transportation demand trends, air transportation system goals, and air transportation system trends well into the 21st century were examined in detail. The outlook is for continued growth in both air passenger travel and air freight movements. The present system, with some improvements, is expected to continue to the turn of the century and to utilize technologically upgraded, derivative versions of today's aircraft, plus possibly some new aircraft for supersonic long haul, short haul, and high density commuter service. Severe constraints of the system, expected by early in the 21st century, should lead to innovations at the airport, away from the airport, and in the air. The innovations are illustrated by descriptions of three candidate systems involving advanced aircraft concepts. Advanced technologies and vehicles expected to impact the airport are illustrated by descriptions of laminar flow control aircraft, very large air freighters and cryogenically fueled transports.

  6. Next Generation NASA GA Advanced Concept

    NASA Technical Reports Server (NTRS)

    Hahn, Andrew S.

    2006-01-01

    Not only is the common dream of frequent personal flight travel going unfulfilled, the current generation of General Aviation (GA) is facing tremendous challenges that threaten to relegate the Single Engine Piston (SEP) aircraft market to a footnote in the history of U.S. aviation. A case is made that this crisis stems from a generally low utility coupled to a high cost that makes the SEP aircraft of relatively low transportation value and beyond the means of many. The roots of this low value are examined in a broad sense, and a Next Generation NASA Advanced GA Concept is presented that attacks those elements addressable by synergistic aircraft design.

  7. Extension-torsion coupling behavior of advanced composite tilt-rotor blades

    NASA Technical Reports Server (NTRS)

    Kosmatka, J. B.

    1989-01-01

    An analytic model was developed to study the extension-bend-twist coupling behavior of an advanced composite helicopter or tilt-rotor blade. The outer surface of the blade is defined by rotating an arbitrary cross section about an initial twist axis. The cross section can be nonhomogeneous and composed of generally anisotropic materials. The model is developed based upon a three dimensional elasticity approach that is recast as a coupled two-dimensional boundary value problem defined in a curvilinear coordinate system. Displacement solutions are written in terms of known functions that represent extension, bending, and twisting and unknown functions for local cross section deformations. The unknown local deformation functions are determined by applying the principle of minimum potential energy to the discretized two-dimensional cross section. This is an application of the Ritz method, where the trial function family is the displacement field associated with a finite element (8-node isoparametric quadrilaterals) representation of the section. A computer program was written where the cross section is discretized into 8-node quadrilateral subregions. Initially the program was verified using previously published results (both three-dimensional elasticity and technical beam theory) for pretwisted isotropic bars with an elliptical cross section. In addition, solid and thin-wall multi-cell NACA-0012 airfoil sections were analyzed to illustrate the pronounced effects that pretwist, initial twist axis location, and spar location has on coupled behavior. Currently, a series of advanced composite airfoils are being modeled in order to assess how the use of laminated composite materials interacts with pretwist to alter the coupling behavior of the blade. These studies will investigate the use of different ply angle orientations and the use of symmetric versus unsymmetric laminates.

  8. ASME Material Challenges for Advanced Reactor Concepts

    SciTech Connect

    Piyush Sabharwall; Ali Siahpush

    2013-07-01

    This study presents the material Challenges associated with Advanced Reactor Concept (ARC) such as the Advanced High Temperature Reactor (AHTR). ACR are the next generation concepts focusing on power production and providing thermal energy for industrial applications. The efficient transfer of energy for industrial applications depends on the ability to incorporate cost-effective heat exchangers between the nuclear heat transport system and industrial process heat transport system. The heat exchanger required for AHTR is subjected to a unique set of conditions that bring with them several design challenges not encountered in standard heat exchangers. The corrosive molten salts, especially at higher temperatures, require materials throughout the system to avoid corrosion, and adverse high-temperature effects such as creep. Given the very high steam generator pressure of the supercritical steam cycle, it is anticipated that water tube and molten salt shell steam generators heat exchanger will be used. In this paper, the ASME Section III and the American Society of Mechanical Engineers (ASME) Section VIII requirements (acceptance criteria) are discussed. Also, the ASME material acceptance criteria (ASME Section II, Part D) for high temperature environment are presented. Finally, lack of ASME acceptance criteria for thermal design and analysis are discussed.

  9. Advanced Gasifier Pilot Plant Concept Definition

    SciTech Connect

    Steve Fusselman; Alan Darby; Fred Widman

    2005-08-31

    This report presents results from definition of a preferred commercial-scale advanced gasifier configuration and concept definition for a gasification pilot plant incorporating those preferred technologies. The preferred commercial gasifier configuration was established based on Cost Of Electricity estimates for an IGCC. Based on the gasifier configuration trade study results, a compact plug flow gasifier, with a dry solids pump, rapid-mix injector, CMC liner insert and partial quench system was selected as the preferred configuration. Preliminary systems analysis results indicate that this configuration could provide cost of product savings for electricity and hydrogen ranging from 15%-20% relative to existing gasifier technologies. This cost of product improvement draws upon the efficiency of the dry feed, rapid mix injector technology, low capital cost compact gasifier, and >99% gasifier availability due to long life injector and gasifier liner, with short replacement time. A pilot plant concept incorporating the technologies associated with the preferred configuration was defined, along with cost and schedule estimates for design, installation, and test operations. It was estimated that a 16,300 kg/day (18 TPD) pilot plant gasifier incorporating the advanced gasification technology and demonstrating 1,000 hours of hot-fire operation could be accomplished over a period of 33 months with a budget of $25.6 M.

  10. ACTS advanced system concepts and experimentation

    NASA Technical Reports Server (NTRS)

    Abbe, Brian S.; Theofylaktos, Noulie

    1993-01-01

    Over the course of the first two years of experimentation with the Advanced Communications Technology Satellite (ACTS), many different K/Ka-band applications-oriented experiments will be conducted and evaluated for their commercial viability. In addition, the technological developments and advanced systems concepts associated with the various terminals and the satellite itself will also be examined. Beyond these existing experiments and the current terminal developments, many other new and exciting experiment ideas and advanced system concepts exist. With the additional use of ACTS for the last two years of its lifetime, many of these ideas could be explored. In the mobile satellite communications arena, a particular applications-oriented concept that has yet to be developed is a maritime-mobile experiment. Applications of K/Ka-band mobile satcom technologies to the pleasure cruise industry could provide similar communications services as those that are being developed for the broadband aeronautical experiments. A second applications-oriented experiment that could be of interest is the development of a hybrid satellite-cellular system experiment. In such an experimental system, a mobile K/Ka-band satellite service would extend the coverage of the already existing cellular network. Many new system concepts and terminal developments could also be accomplished. The initial characterization of the K/Ka-band mobile satellite communications propagation channel and evaluation of the currently existing rain compensation algorithms (RCA's) could lead to a second generation RCA development that would improve the overall ACTS Mobile Terminal (AMT) performance. In addition, the development of an enhanced modem to be used with the AMT that utilizes CDMA spread spectrum would also improve the overall terminal efficiency and provide a greater commercial potential for K/Ka-band applications. Other techniques worthy of further exploration and evaluation include the development of

  11. High Temperature Investigations into an Active Turbine Blade Tip Clearance Control Concept

    NASA Technical Reports Server (NTRS)

    Taylor, Shawn; Steinetz, Bruce M.; Oswald, Jay J.

    2007-01-01

    System studies have shown the benefits of reducing blade tip clearances in modern turbine engines. Minimizing blade tip clearances throughout the engine will contribute materially to meeting NASA s Ultra-Efficient Engine Technology (UEET) turbine engine project goals. NASA GRC is examining two candidate approaches including rub-avoidance and regeneration which are explained in subsequent slides.

  12. High Temperature Investigations into an Active Turbine Blade Tip Clearance Control Concept

    NASA Technical Reports Server (NTRS)

    Taylor, Shawn C.; Steinetz, Bruce; Oswald, Jay J.

    2008-01-01

    System studies have shown the benefits of reducing blade tip clearances in modern turbine engines. Minimizing blade tip clearances throughout the engine will contribute materially to meeting NASA s Ultra-Efficient Engine Technology (UEET) turbine engine project goals. NASA GRC is examining two candidate approaches including rub-avoidance and regeneration which are explained in subsequent slides.

  13. The effect of helicopter main rotor blade phasing and spacing on performance, blade loads, and acoustics

    NASA Technical Reports Server (NTRS)

    Gangwani, S. T.

    1976-01-01

    The performance, blade loads, and acoustic characteristics of a variable geometry rotor (VGR) system in forward flight and in a pullup maneuver were determined by the use of existing analytical programs. The investigation considered the independent effects of vertical separation of two three-bladed rotor systems as well as the effects of azimuthal spacing between the blades of the two rotors. The computations were done to determine the effects of these parameters on the performance, blade loads, and acoustic characteristics at two advance ratios in steady-state level flight and for two different g pullups at one advance ratio. To evaluate the potential benefits of the VGR concept in forward flight and pullup maneuvers, the results were compared as to performance, oscillatory blade loadings, vibratory forces transmitted to the fixed fuselage, and the rotor noise characteristics of the various VGR configurations with those of the conventional six-bladed rotor system.

  14. Advanced composite combustor structural concepts program

    NASA Technical Reports Server (NTRS)

    Sattar, M. A.; Lohmann, R. P.

    1984-01-01

    An analytical study was conducted to assess the feasibility of and benefits derived from the use of high temperature composite materials in aircraft turbine engine combustor liners. The study included a survey and screening of the properties of three candidate composite materials including tungsten reinforced superalloys, carbon-carbon and silicon carbide (SiC) fibers reinforcing a ceramic matrix of lithium aluminosilicate (LAS). The SiC-LAS material was selected as offering the greatest near term potential primarily on the basis of high temperature capability. A limited experimental investigation was conducted to quantify some of the more critical mechanical properties of the SiC-LAS composite having a multidirection 0/45/-45/90 deg fiber orientation favored for the combustor linear application. Rigorous cyclic thermal tests demonstrated that SiC-LAS was extremely resistant to the thermal fatigue mechanisms that usually limit the life of metallic combustor liners. A thermal design study led to the definition of a composite liner concept that incorporated film cooled SiC-LAS shingles mounted on a Hastelloy X shell. With coolant fluxes consistent with the most advanced metallic liner technology, the calculated hot surface temperatures of the shingles were within the apparent near term capability of the material. Structural analyses indicated that the stresses in the composite panels were low, primarily because of the low coefficient of expansion of the material and it was concluded that the dominant failure mode of the liner would be an as yet unidentified deterioration of the composite from prolonged exposure to high temperature. An economic study, based on a medium thrust size commercial aircraft engine, indicated that the SiC-LAS combustor liner would weigh 22.8N (11.27 lb) less and cost less to manufacture than advanced metallic liner concepts intended for use in the late 1980's.

  15. Aerodynamic design and performance testing of an advanced 30 deg swept, eight bladed propeller at Mach numbers from 0.2 to 0.85

    NASA Technical Reports Server (NTRS)

    Black, D. M.; Menthe, R. W.; Wainauski, H. S.

    1978-01-01

    The increased emphasis on fuel conservation in the world has stimulated a series of studies of both conventional and unconventional propulsion systems for commercial aircraft. Preliminary results from these studies indicate that a fuel saving of from 15 to 28 percent may be realized by the use of an advanced high speed turboprop. The turboprop must be capable of high efficiency at Mach 0.8 above 10.68 km (35,000 ft) altitude if it is to compete with turbofan powered commercial aircraft. An advanced turboprop concept was wind tunnel tested. The model included such concepts as an aerodynamically integrated propeller/nacelle, blade sweep and power (disk) loadings approximately three times higher than conventional propeller designs. The aerodynamic design for the model is discussed. Test results are presented which indicate propeller net efficiencies near 80 percent were obtained at high disk loadings at Mach 0.8.

  16. Experimental assessment of advanced Stirling component concepts

    NASA Technical Reports Server (NTRS)

    Ziph, B.

    1985-01-01

    The results of an experimental assessment of some advanced Stirling engine component concepts are presented. High performance piston rings, reciprocating oil scrapers and heat pipes with getters and with mechanical couplings were tested. The tests yielded the following results: (1) Bonded, split, pumping piston rings, in preliminary testing, proved a promising concept, exhibiting low leakage and friction losses. Solid piston rings proved impractical in view of their sensitivity to the operating temperature; (2) A babbit oil scraper in a compliant housing performed well in atmospheric endurance testing. In pressurized tests the scraper did not perform well as a containment seal. The latter tests suggest modifications which may adapt Ti successfully to that application; and (3) Heat pipe endurance tests indicated the adequacy of simple, inexpensive fabrication and filling procedures. Getters were provided to increase the tolerance of the heat pipes to the presence of air and commercially available couplings were demonstrated to be suitable for heat pipe application. In addition to the above tests, the program also included a design effort for a split shaft applicable to a swashplate driven engine with a pressurized crank-case. The design is aimed, and does accomplish, an increase in component life to more than 10,000 hours.

  17. Advanced Nacelle Acoustic Lining Concepts Development

    NASA Technical Reports Server (NTRS)

    Bielak, G.; Gallman, J.; Kunze, R.; Murray, P.; Premo, J.; Kosanchick, M.; Hersh, A.; Celano, J.; Walker, B.; Yu, J.; Parrott, Tony L. (Technical Monitor)

    2002-01-01

    The work reported in this document consisted of six distinct liner technology development subtasks: 1) Analysis of Model Scale ADP Fan Duct Lining Data (Boeing): An evaluation of an AST Milestone experiment to demonstrate 1995 liner technology superiority relative to that of 1992 was performed on 1:5.9 scale model fan rig (Advanced Ducted Propeller) test data acquired in the NASA Glenn 9 x 15 foot wind tunnel. The goal of 50% improvement was deemed satisfied. 2) Bias Flow Liner Investigation (Boeing, VCES): The ability to control liner impedance by low velocity bias flow through liner was demonstrated. An impedance prediction model to include bias flow was developed. 3) Grazing Flow Impedance Testing (Boeing): Grazing flow impedance tests were conducted for comparison with results achieved at four different laboratories. 4) Micro-Perforate Acoustic Liner Technology (BFG, HAE, NG): Proof of concept testing of a "linear liner." 5) Extended Reaction Liners (Boeing, NG): Bandwidth improvements for non-locally reacting liner were investigated with porous honeycomb core test liners. 6) Development of a Hybrid Active/Passive Lining Concept (HAE): Synergism between active and passive attenuation of noise radiated by a model inlet was demonstrated.

  18. Introduction to Advanced Engine Control Concepts

    NASA Technical Reports Server (NTRS)

    Sanjay, Garg

    2007-01-01

    With the increased emphasis on aircraft safety, enhanced performance and affordability, and the need to reduce the environmental impact of aircraft, there are many new challenges being faced by the designers of aircraft propulsion systems. The Controls and Dynamics Branch at NASA (National Aeronautics and Space Administration) Glenn Research Center (GRC) in Cleveland, Ohio, is leading and participating in various projects in partnership with other organizations within GRC and across NASA, the U.S. aerospace industry, and academia to develop advanced controls and health management technologies that will help meet these challenges through the concept of Intelligent Propulsion Systems. The key enabling technologies for an Intelligent Propulsion System are the increased efficiencies of components through active control, advanced diagnostics and prognostics integrated with intelligent engine control to enhance operational reliability and component life, and distributed control with smart sensors and actuators in an adaptive fault tolerant architecture. This presentation describes the current activities of the Controls and Dynamics Branch in the areas of active component control and propulsion system intelligent control, and presents some recent analytical and experimental results in these areas.

  19. A numerical technique for calculation of the noise of high-speed propellers with advanced blade geometry

    NASA Technical Reports Server (NTRS)

    Nystrom, P. A.; Farassat, F.

    1980-01-01

    A numerical technique and computer program were developed for the prediction of the noise of propellers with advanced geometry. The blade upper and lower surfaces are described by a curvilinear coordinate system, which was also used to divide the blade surfaces into panels. Two different acoustic formulations in the time domain were used to improve the speed and efficiency of the noise calculations: an acoustic formualtion with the Doppler factor singularity for panels moving at subsonic speeds and the collapsing sphere formulation for panels moving at transonic or supersonic speeds. This second formulation involves a sphere which is centered at the observer position and whose radius decreases at the speed of sound. The acoustic equation consisted of integrals over the curve of intersection for both the sphere and the panels on the blade. Algorithms used in some parts of the computer program are discussed. Comparisons with measured acoustic data for two model high speed propellers with advanced geometry are also presented.

  20. Test Rig for Active Turbine Blade Tip Clearance Control Concepts: An Update

    NASA Technical Reports Server (NTRS)

    Taylor, Shawn; Steinetz, Bruce; Oswald, Jay; DeCastro, Jonathan; Melcher, Kevin

    2006-01-01

    The objective is to develop and demonstrate a fast-acting active clearance control system to improve turbine engine performance, reduce emissions, and increase service life. System studies have shown the benefits of reducing blade tip clearances in modern turbine engines. Minimizing blade tip clearances throughout the engine will contribute materially to meeting NASA's Ultra-Efficient Engine Technology (UEET) turbine engine project goals. NASA GRC is examining two candidate approaches including rub-avoidance and regeneration which are explained in subsequent slides.

  1. NASA Lewis Helps Develop Advanced Saw Blades for the Lumber Industry

    NASA Technical Reports Server (NTRS)

    1998-01-01

    NASA Lewis Research Center's Structures and Material Divisions are centers of excellence in high-temperature alloys for aerospace applications such as advanced aircraft and rocket engines. Lewis' expertise in these fields was enlisted in the development of a new generation of circular sawblades for the lumber industry to use in cutting logs into boards. The U.S. Department of Agriculture's (USDA) Forest Products Laboratory and their supplier had succeeded in developing a thinner sawblade by using a nickel-based alloy, but they needed to reduce excessive warping due to residual stresses. They requested assistance from Lewis' experts, who successfully eliminated the residual stress problem and increased blade strength by over 12 percent. They achieved this by developing an innovative heat treatment based on their knowledge of nickel-based superalloys used in aeropropulsion applications.

  2. Computer experiments on periodic systems identification using rotor blade transient flapping-torsion responses at high advance ratio

    NASA Technical Reports Server (NTRS)

    Hohenemser, K. H.; Prelewicz, D. A.

    1974-01-01

    Systems identification methods have recently been applied to rotorcraft to estimate stability derivatives from transient flight control response data. While these applications assumed a linear constant coefficient representation of the rotorcraft, the computer experiments described in this paper used transient responses in flap-bending and torsion of a rotor blade at high advance ratio which is a rapidly time varying periodic system.

  3. The NASA Advanced Propulsion Concepts at the Jet Propulsion Laboratory

    NASA Technical Reports Server (NTRS)

    Leifer, S. D.; Frisbee, R. H.; Brophy, J. R.

    1997-01-01

    Research activities in advanced propulsion concepts at the Jet Propulsion Laboratory are reviewed. The concepts were selected for study because each offers the potential for either significantly enhancing space transportation capability or enabling bold, ambitious new missions.

  4. Advanced Technology Display House. Volume 2: Energy system design concepts

    NASA Technical Reports Server (NTRS)

    Maund, D. H.

    1981-01-01

    The preliminary design concept for the energy systems in the Advanced Technology Display House is analyzed. Residential energy demand, energy conservation, and energy concepts are included. Photovoltaic arrays and REDOX (reduction oxidation) sizes are discussed.

  5. Advanced-Ignition-Concept Exploration on OMEGA

    SciTech Connect

    Theobald, W; Anderson, K S; Betti, R; Craxton, R S; Delettrez, J A; Frenje, J A; Glebov, V Yu; Gotchev, O V; Kelly, J H; Li, C K; Mackinnon, A J; Marshall, F J; McCrory, R L; Meyerhofer, D D; Myatt, J F; Norreys, P A; Nilson, P M; Patel, P K; Petrasso, R D; Radha, P B; Ren, C; Sangster, T C; Seka, W; Smalyuk, V A; Solodov, A A; Stephens, R B; Stoeckl, C; Yaakobi, B

    2009-11-24

    Advanced ignition concepts, such as fast ignition and shock ignition, are being investigated at the Omega Laser Facility. Integrated fast-ignition experiments with room-temperature re-entrant cone targets have begun, using 18 kJ of 351 nm drive energy to implode empty 40μm thick CD shells, followed by 1.0 kJ of 1053 nm wavelength, short-pulse energy. Short pulses of 10 ps width have irradiated the inside of a hollow gold re-entrant cone at the time of peak compression. A threefold increase in the time-integrated, 2 to 7 keV x-ray emission was observed with x-ray pinhole cameras, indicating that energy is coupled from the short-pulse laser into the core by fast electrons. In shock-ignition experiments, spherical plastic-shell targets were compressed to high areal densities on a low adiabat, and a strong shock wave was sent into the converging, compressed capsule. In one experiment, 60 beams were used with an intensity spike at the end of the laser pulse, and the implosion performance was studied through neutron-yield and areal-density measurements. In a second experiment, the 60 OMEGA beams were split into a 40+20 configuration, with 40 low-intensity beams used for fuel assembly and 20 delayed beams with a short, high-intensity pulse shape (up to 1×1016 Wcm^-2) for shock generation.

  6. Advanced-Ignition-Concept Exploration on OMEGA

    SciTech Connect

    Theobald, W; Anderson, K S; Betti, R; Craxton, R S; Delettrez, J A; Frenje, J A; Glebov, V Yu; Gotchev, O V; Kelly, J H; Li, C K; Mackinnon, A J; Marshall, F J; McCrory, R L; Meyerhofer, D D; Myatt, J F; Norreys, P A; Nilson, P M; Patel, P K; Petrasso, R D; Radha, P B; Ren, C; Sangster, T C; Seka, W; Smalyuk, V A; Solodov, A A; Stephens, R B; Stoeckl, C; Yaakobi, B

    2009-11-24

    Advanced ignition concepts, such as fast ignition and shock ignition, are being investigated at the Omega Laser Facility. Integrated fast-ignition experiments with room-temperature re-entrant cone targets have begun, using 18 kJ of 351 nm drive energy to implode empty 40μm thick CD shells, followed by 1.0 kJ of 1053 nm wavelength, short-pulse energy. Short pulses of 10 ps width have irradiated the inside of a hollow gold re-entrant cone at the time of peak compression. A threefold increase in the time-integrated, 2 to 7 keV x-ray emission was observed with x-ray pinhole cameras, indicating that energy is coupled from the short-pulse laser into the core by fast electrons. In shock-ignition experiments, spherical plastic-shell targets were compressed to high areal densities on a low adiabat, and a strong shock wave was sent into the converging, compressed capsule. In one experiment, 60 beams were used with an intensity spike at the end of the laser pulse, and the implosion performance was studied through neutron-yield and areal-density measurements. In a second experiment, the 60 OMEGA beams were split into a 40+20 configuration, with 40 low-intensity beams used for fuel assembly and 20 delayed beams with a short, high-intensity pulse shape (up to 1×1016 Wcm-2) for shock generation.

  7. Preliminary design study of advanced composite blade and hub and nonmechanical control system for the tilt-rotor aircraft. Volume 1: Engineering studies

    NASA Technical Reports Server (NTRS)

    Alexander, H. R.; Smith, K. E.; Mcveigh, M. A.; Dixon, P. G.; Mcmanus, B. L.

    1979-01-01

    Composite structures technology is applied in a preliminary design study of advanced technology blades and hubs for the XV-15 tilt rotor research demonstrator aircraft. Significant improvements in XV-15 hover and cruise performance are available using blades designed for compatibility with the existing aircraft, i.e., blade installation would not require modification of the airframe, hub or upper controls. Provision of a low risk nonmechanical control system was also studied, and a development specification is given.

  8. Hover performance tests of baseline metal and Advanced Technology Blade (ATB) rotor systems for the XV-15 tilt rotor aircraft

    NASA Technical Reports Server (NTRS)

    Bartie, K.; Alexander, H.; Mcveigh, M.; Lamon, S.; Bishop, H.

    1986-01-01

    Rotor hover performance data were obtained for two full-scale rotor systems designed for the XV-15 Tilt Rotor Research Aircraft. One rotor employed the rectangular planform metal blades (rotor solidity = 0.089) which were used on the initial flight configuration of the XV-15. The second rotor configuration examined the nonlinear taper, composite-construction, Advanced Technology Blade (ATB), (rotor solidity = 0.10) designed to replace the metal blades on the XV-15. Variations of the baseline ATB tip and cuff shapes were also tested. A new six-component rotor force and moment balance designed to obtain highly accurate data over a broad range of thrust and torque conditions is described. The test data are presented in nondimensional coefficient form for the performance results, and in dimensional form for the steady and alternating loads. Some wake and acoustic data are also shown.

  9. Infrared thermography inspection of glass reinforced plastic (GRP) wind turbine blades and the concept of an automated scanning device

    NASA Astrophysics Data System (ADS)

    Avdelidis, Nicolas P.; Ibarra-Castanedo, C.; Maldague, X. P. V.

    2013-05-01

    Infrared thermography techniques have been used for many years in the non-destructive testing and evaluation (NDT and E) of materials and structures. The main advantage of thermography over classical NDT techniques resides in the possibility of inspecting large areas in a fast and safe manner without needing to have access to both sides of the component. Nonetheless infrared thermography is limited to the detection of relatively shallow defects (a few millimetres under the surface), since it is affected by 3D heat diffusion. However, the most common types of anomalies found on composites, such as GRP wind turbine blades are delaminations, disbonds, water ingress, node failure and core crushing, and can be effectively detected and sometimes quantified using active thermographic techniques. This research work presents the use of infrared thermography on glass reinforced plastic (GRP) wind turbine blades assessment. Finally, the development of an autonomous, novel and lightweight multi-axis scanning system, as a concept, deploying in situ thermography NDT is also presented, with the intention of developing maximisation of the blade area coverage in a single run, at a known sensitivity, with the utilisation of the minimum number of system degrees of freedom and the maximum repeatability, as well as positional accuracy possible.

  10. Test Rig for Evaluating Active Turbine Blade Tip Clearance Control Concepts

    NASA Technical Reports Server (NTRS)

    Lattime, Scott B.; Steinetz, Bruce M.; Robbie, Malcolm G.

    2003-01-01

    Improved blade tip sealing in the high pressure compressor and high pressure turbine can provide dramatic improvements in specific fuel consumption, time-on-wing, compressor stall margin and engine efficiency as well as increased payload and mission range capabilities of both military and commercial gas turbine engines. The preliminary design of a mechanically actuated active clearance control (ACC) system for turbine blade tip clearance management is presented along with the design of a bench top test rig in which the system is to be evaluated. The ACC system utilizes mechanically actuated seal carrier segments and clearance measurement feedback to provide fast and precise active clearance control throughout engine operation. The purpose of this active clearance control system is to improve upon current case cooling methods. These systems have relatively slow response and do not use clearance measurement, thereby forcing cold build clearances to set the minimum clearances at extreme operating conditions (e.g., takeoff, re-burst) and not allowing cruise clearances to be minimized due to the possibility of throttle transients (e.g., step change in altitude). The active turbine blade tip clearance control system design presented herein will be evaluated to ensure that proper response and positional accuracy is achievable under simulated high-pressure turbine conditions. The test rig will simulate proper seal carrier pressure and temperature loading as well as the magnitudes and rates of blade tip clearance changes of an actual gas turbine engine. The results of these evaluations will be presented in future works.

  11. Materials for advanced turbine engines. Project 2: Rene 150 directionally solidified superalloy turbine blades, volume 2

    NASA Technical Reports Server (NTRS)

    Deboer, G. J.

    1982-01-01

    The results of the engine testing of Rene 150 Stage 1 high pressure turbine blades in CF6-50 core and fan engines are presented. The core engine test was conducted for 233 hours with a variety of test cycles, and the fan engine test was conducted for 1000 C cycles. Post-test analysis of the core engine test data confirmed the suitability of the Rene 150 HPT blade for fan engine testing. Post-test evaluation and analysis of the fan engine test blades included visual and dimensional inspection as well as metallographic examination of selected blades. The Rene 150 HPT blade met the target goal of this project by demonstrating increased metal temperature capability; however, the post-test analysis revealed several areas that would have to be addressed in designing a long-life Rene 150 CF6-50 HPT blade.

  12. Technical and economic evaluation of advanced air cargo system concepts

    NASA Technical Reports Server (NTRS)

    Whitehead, A. H., Jr.

    1977-01-01

    The paper reviews NASA air cargo market studies, reports on NASA and NASA-sponsored studies of advanced freighter concepts, and identifies the opportunities for the application of advanced technology. The air cargo market is studied to evaluate the timing for, and the potential market response to, advanced technology aircraft. The degree of elasticity in future air freight markets is also being investigated, since the demand for a new aircraft is most favorable in a price-sensitive environment. Aircraft design studies are considered with attention to mission and design requirements, incorporation of advanced technologies in transport aircraft, new cargo aircraft concepts, advanced freighter evaluation, and civil-military design commonality.

  13. Advanced sunflower antenna concept development. [stowable reflectors

    NASA Technical Reports Server (NTRS)

    Archer, J. S.

    1980-01-01

    The feasibility of stowing large solid antenna reflectors in the shuttle was demonstrated for applications with 40 foot apertures at frequencies of 100 GHz. Concepts allowing extension of the basic concept to 80-foot apertures operable at 60 GHz were identified.

  14. SERI Advanced and Innovative Wind-Energy-Concepts Program

    SciTech Connect

    Mitchell, R.L.; Jacobs, E.W.

    1983-06-01

    In 1978 the Solar Energy Research Institute (SERI) was given the responsibility of managing the Advanced and Innovative Wind Energy Concepts (AIWEC) Task by the US Department of Energy (DOE). The objective of this program has been to determine the technical and economic potential of advanced wind energy concepts. Assessment and R and D efforts in the AIWEC program have included theoretical performance analyses, wind tunnel testing, and/or costing studies. Concepts demonstrating sufficient potential undergo prototype testing in a Proof-of-Concept research phase. Several concepts, such as the Dynamic Inducer, the Diffuser Augmented wind Turbine, the Electrofluid Dynamic Wind-Driven Generator, the Passive Cyclic Pitch concept, and higher performance airfoil configurations for vertical axis wind turbines, have recently made significant progress. The latter has currently reached the Proof-of-Concept phase. The present paper provides an overview of the technical progress and current status of these concepts.

  15. Advanced Wind Turbine Drivetrain Concepts. Workshop Report

    SciTech Connect

    none,

    2010-12-01

    This report presents key findings from the Department of Energy’s Advanced Drivetrain Workshop, held on June 29-30, 2010, to assess different advanced drivetrain technologies, their relative potential to improve the state-of-the-art in wind turbine drivetrains, and the scope of research and development needed for their commercialization in wind turbine applications.

  16. Design and fabrication of forward-swept counterrotation blade configuration for wind tunnel testing

    NASA Technical Reports Server (NTRS)

    Nichols, G. H.

    1994-01-01

    Work performed by GE Aircraft on advanced counterrotation blade configuration concepts for high speed turboprop system is described. Primary emphasis was placed on theoretically and experimentally evaluating the aerodynamic, aeromechanical, and acoustic performance of GE-defined counterrotating blade concepts. Several blade design concepts were considered. Feasibility studies were conducted to evaluate a forward-swept versus an aft-swept blade application and how the given blade design would affect interaction between rotors. Two blade designs were initially selected. Both designs involved in-depth aerodynamic, aeromechanical, mechanical, and acoustic analyses followed by the fabrication of forward-swept, forward rotor blade sets to be wind tunnel tested with an aft-swept, aft rotor blade set. A third blade set was later produced from a NASA design that was based on wind tunnel test results from the first two blade sets. This blade set had a stiffer outer ply material added to the original blade design, in order to reach the design point operating line. Detailed analyses, feasibility studies, and fabrication procedures for all blade sets are presented.

  17. Measured and predicted rotor performance for the SERI advanced wind turbine blades

    SciTech Connect

    Tangler, J.; Smith, B.; Kelley, N.; Jager, D.

    1992-02-01

    Measured and predicted rotor performance for the SERI advanced wind turbine blades were compared to assess the accuracy of predictions and to identify the sources of error affecting both predictions and measurements. An awareness of these sources of error contributes to improved prediction and measurement methods that will ultimately benefit future rotor design efforts. Propeller/vane anemometers were found to underestimate the wind speed in turbulent environments such as the San Gorgonio Pass wind farm area. Using sonic or cup anemometers, good agreement was achieved between predicted and measured power output for wind speeds up to 8 m/sec. At higher wind speeds an optimistic predicted power output and the occurrence of peak power at wind speeds lower than measurements resulted from the omission of turbulence and yaw error. In addition, accurate two-dimensional (2-D) airfoil data prior to stall and a post stall airfoil data synthesization method that reflects three-dimensional (3-D) effects were found to be essential for accurate performance prediction. 11 refs.

  18. Techniques Optimized for Reducing Instabilities in Advanced Nickel-Base Superalloys for Turbine Blades

    NASA Technical Reports Server (NTRS)

    MacKay, Rebecca A.; Locci, Ivan E.; Garg, anita; Ritzert, Frank J.

    2002-01-01

    is a three-phase constituent composed of TCP and stringers of gamma phase in a matrix of gamma prime. An incoherent grain boundary separates the SRZ from the gammagamma prime microstructure of the superalloy. The SRZ is believed to form as a result of local chemistry changes in the superalloy due to the application of the diffusion aluminide bondcoat. Locally high surface stresses also appear to promote the formation of the SRZ. Thus, techniques that change the local alloy chemistry or reduce surface stresses have been examined for their effectiveness in reducing SRZ. These SRZ-reduction steps are performed on the test specimen or the turbine blade before the bondcoat is applied. Stressrelief heat treatments developed at NASA Glenn have been demonstrated to reduce significantly the amount of SRZ that develops during subsequent high-temperature exposures. Stress-relief heat treatments reduce surface stresses by recrystallizing a thin surface layer of the superalloy. However, in alloys with very high propensities to form SRZ, stress relief heat treatments alone do not eliminate SRZ entirely. Thus, techniques that modify the local chemistry under the bondcoat have been emphasized and optimized successfully at Glenn. One such technique is carburization, which changes the local chemistry by forming submicron carbides near the surface of the superalloy. Detailed characterizations have demonstrated that the depth and uniform distribution of these carbides are enhanced when a stress relief treatment and an appropriate surface preparation are employed in advance of the carburization treatment. Even in alloys that have the propensity to develop a continuous SRZ layer beneath the diffusion zone, the SRZ has been completely eliminated or reduced to low, manageable levels when this combination of techniques is utilized. Now that the techniques to mitigate SRZ have been established at Glenn, TCP phase formation is being emphasized in ongoing work under the UEET Program. The

  19. Flap-lag dynamics of hingeless helicopter blades at moderate and high advance ratios

    NASA Technical Reports Server (NTRS)

    Friedman, P.; Silverthorn, L. J.

    1974-01-01

    Equations for large amplitude coupled flaplag motion of a hingeless elastic helicopter blade in forward flight are derived. Only a torsionally rigid blade exicted by quasi-steady aerodynamic loads is considered. The effects of reversed flow together with some new terms due to forward flight are included. Using Galerkin's method the spatial dependence is eliminated and the equations are linearized about a suitable equilibrium position. The resulting system of equations is solved using multivariable Floquet-Liapunov theory, and the transition matrix at the end of the period is evaluated by two separate methods. Results illustrating the effects of forward flight and various important blade parameters on the stability boundaries are presented.

  20. Process Technology and Advanced Concepts: Organic Solar Cells (Fact Sheet)

    SciTech Connect

    Not Available

    2011-06-01

    Capabilities fact sheet for the National Center for Photovoltaics: Process Technology and Advanced Concepts: Organic Solar Cell that includes scope, core competencies and capabilities, and contact/web information.

  1. Aircraft concepts for advanced short haul systems

    NASA Technical Reports Server (NTRS)

    Galloway, T. L.

    1975-01-01

    The results of recent NASA-sponsored high-density and medium-density short-haul (less than 500 miles) air transportation systems studies are summarized. Trends in vehicle characteristics, in particular of RTOL and STOL concepts, are noted, and their economic suitability and impact on the community are examined.

  2. Body weight of advanced concept hypersonic aircraft

    NASA Technical Reports Server (NTRS)

    Ardema, Mark D.; Terjesen, Eric J.; Roberts, Cathy D.; Chambers, Mark C.

    1991-01-01

    In this paper, preliminary qualitative and quantitative comparisons of the body weight of five hypersonic aircraft configurations are conducted. The five configurations are briefly described as follows: (1) a wing-and-body arrangement with a power-law, circular cross-section body and a delta wing; (2) an all-body vehicle with delta planform and elliptical cross-sections; (3) a wingless wave rider configuration; (4) a winged wave rider configuration; and (5) the spacewing concept, an oblique flying wing at low speed that yaws to 90 deg sweep and flies end-on at hypersonic speeds. The vehicles are defined by their external moldline geometries and by the interior arrangement of their fuel tanks and other components. Intersecting, circular-lobed tankage is used in vehicles with noncircular bodies. The nonusable volume of such concepts is calculated. The structural concept, structural materials, Thermal Protection System, and heat load are allowed to vary with vehicle longitudinal station. Relative strengths and weaknesses of the various hypersonic aircraft concepts in terms of body weight are summarized.

  3. Advanced Propulsion Concepts at the Jet Propulsion Laboratory

    NASA Technical Reports Server (NTRS)

    Brophy, J. R.

    1997-01-01

    Current interest in advanced propulsion within NASA and research activities in advanced propulsion concepts at the Jet Propulsion Laboratory are reviewed. The concepts, which include high power plasma thrusters such as lithuim-fueled Lorentz-Force-Accelerators, MEMS-scale propulsion systems, in-situ propellant utilization techniques, fusion propulsion systems and methods of using antimatter, offer the potential for either significantly enhancing space transportation capability as compared with that of traditional chemical propulsion, or enabling ambitious new missions.

  4. Screening studies of advanced control concepts for airbreathing engines

    NASA Technical Reports Server (NTRS)

    Ouzts, Peter J.; Lorenzo, Carl F.; Merrill, Walter C.

    1993-01-01

    The application of advanced control concepts to airbreathing engines may yield significant improvements in aircraft/engine performance and operability. Accordingly, the NASA Lewis Research Center has conducted screening studies of advanced control concepts for airbreathing engines to determine their potential impact on turbine engine performance and operability. The purpose of the studies was to identify concepts which offered high potential yet may incur high research and development risk. A target suite of proposed concepts was formulated by NASA and industry. These concepts were evaluated in a two phase study to quantify each concept's impact on desired engine characteristics. To aid in the evaluation, three target aircraft/engine combinations were considered: a military high performance fighter mission, a high speed civil transport mission, and a civil tiltrotor mission. Each of the advanced control concepts considered in the study were defined and described. The concept's potential impact on engine performance was determined. Relevant figures of merit on which to evaluate the concepts were also determined. Finally, the concepts were ranked with respect to the target aircraft/engine missions.

  5. Screening studies of advanced control concepts for airbreathing engines

    NASA Technical Reports Server (NTRS)

    Ouzts, Peter J.; Lorenzo, Carl F.; Merrill, Walter C.

    1992-01-01

    The application of advanced control concepts to airbreathing engines may yield significant improvements in aircraft/engine performance and operability. Accordingly, the NASA Lewis Research Center has conducted screening studies of advanced control concepts for airbreathing engines to determine their potential impact on turbine engine performance and operability. The purpose of the studies was to identify concepts which offered high potential yet may incur high research and development risk. A target suite of proposed concepts was formulated by NASA and industry. These concepts were evaluated in a two phase study to quantify each concept's impact on desired engine characteristics. To aid in the evaluation, three target aircraft/engine combinations were considered: a military high performance fighter mission, a high speed civil transport mission, and a civil tiltrotor mission. Each of the advanced control concepts considered in the study were defined and described. The concept's potential impact on engine performance was determined. Relevant figures of merit on which to evaluate the concepts were also determined. Finally, the concepts were ranked with respect to the target aircraft/engine missions.

  6. Advanced Interval Management (IM) Concepts of Operations

    NASA Technical Reports Server (NTRS)

    Barmore, Bryan E.; Ahmad, Nash'at N.; Underwood, Matthew C.

    2014-01-01

    This document provides a high-level description of several advanced IM operations that NASA is considering for future research and development. It covers two versions of IM-CSPO and IM with Wake Mitigation. These are preliminary descriptions to support an initial benefits analysis

  7. Advanced concepts for controlling energy surety microgrids.

    SciTech Connect

    Menicucci, David F.; Ortiz-Moyet, Juan

    2011-05-01

    Today, researchers, engineers, and policy makers are seeking ways to meet the world's growing demand for energy while addressing critical issues such as energy security, reliability, and sustainability. Many believe that distributed generators operating within a microgrid have the potential to address most of these issues. Sandia National Laboratories has developed a concept called energy surety in which five of these 'surety elements' are simultaneously considered: energy security, reliability, sustainability, safety, and cost-effectiveness. The surety methodology leads to a new microgrid design that we call an energy surety microgrid (ESM). This paper discusses the unique control requirement needed to produce a microgrid system that has high levels of surety, describes the control system from the most fundamental level through a real-world example, and discusses our ideas and concepts for a complete system.

  8. Workshop II: Nanotechnology and Advanced Cell Concepts

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Workshop focused on few emerging concepts(beyond tandem cells): 1. Engineering incident sun spectrum and transparency losses a) Nano emitters (dot concentrator); b) Surface plasmonics; c) Up converters; d) Down converter. 2. Intermediate band solar cells a) Efficiency projections (detail energy balance projections); b) Inserting 0,1 and 2D semiconductor structures in solar cells 3. Polymer and hybrid cells a) Nanotubes/dot polymers; b) Exciton dissociation.

  9. Advanced General Aviation Turbine Engine (GATE) concepts

    NASA Technical Reports Server (NTRS)

    Lays, E. J.; Murray, G. L.

    1979-01-01

    Concepts are discussed that project turbine engine cost savings through use of geometrically constrained components designed for low rotational speeds and low stress to permit manufacturing economies. Aerodynamic development of geometrically constrained components is recommended to maximize component efficiency. Conceptual engines, airplane applications, airplane performance, engine cost, and engine-related life cycle costs are presented. The powerplants proposed offer encouragement with respect to fuel efficiency and life cycle costs, and make possible remarkable airplane performance gains.

  10. Red Teaming of Advanced Information Assurance Concepts

    SciTech Connect

    DUGGAN,RUTH A.; WOOD,BRADLEY

    1999-10-07

    Red Teaming is an advanced form of assessment that can be used to identify weaknesses in a variety of cyber systems. it is especially beneficial when the target system is still in development when designers can readily affect improvements. This paper discusses the red team analysis process and the author's experiences applying this process to five selected Information Technology Office (ITO) projects. Some detail of the overall methodology, summary results from the five projects, and lessons learned are contained within this paper.

  11. Blade system design studies volume II : preliminary blade designs and recommended test matrix.

    SciTech Connect

    Griffin, Dayton A.

    2004-06-01

    As part of the U.S. Department of Energy's Wind Partnerships for Advanced Component Technologies (WindPACT) program, Global Energy Concepts, LLC is performing a Blade System Design Study (BSDS) concerning innovations in materials, processes and structural configurations for application to wind turbine blades in the multi-megawatt range. The BSDS Volume I project report addresses issues and constraints identified to scaling conventional blade designs to the megawatt size range, and evaluated candidate materials, manufacturing and design innovations for overcoming and improving large blade economics. The current report (Volume II), presents additional discussion of materials and manufacturing issues for large blades, including a summary of current trends in commercial blade manufacturing. Specifications are then developed to guide the preliminary design of MW-scale blades. Using preliminary design calculations for a 3.0 MW blade, parametric analyses are performed to quantify the potential benefits in stiffness and decreased gravity loading by replacement of a baseline fiberglass spar with carbon-fiberglass hybrid material. Complete preliminary designs are then presented for 3.0 MW and 5.0 MW blades that incorporate fiberglass-to-carbon transitions at mid-span. Based on analysis of these designs, technical issues are identified and discussed. Finally, recommendations are made for composites testing under Part I1 of the BSDS, and the initial planned test matrix for that program is presented.

  12. An overview of the NASA Advanced Propulsion Concepts program

    SciTech Connect

    Curran, F.M.; Bennett, G.L.; Frisbee, R.H.; Sercel, J.C.; Lapointe, M.R. JPL, Pasadena, CA Sverdrup Technology, Inc., Brook Park, OH NASA, Lewis Research Center, Cleveland, OH )

    1992-07-01

    NASA Advanced Propulsion Concepts (APC) program for the development of long-term space propulsion system schemes is managed by both NASA-Lewis and the JPL and is tasked with the identification and conceptual development of high-risk/high-payoff configurations. Both theoretical and experimental investigations have been undertaken in technology areas deemed essential to the implementation of candidate concepts. These APC candidates encompass very high energy density chemical propulsion systems, advanced electric propulsion systems, and an antiproton-catalyzed nuclear propulsion concept. A development status evaluation is presented for these systems. 45 refs.

  13. An overview of the NASA Advanced Propulsion Concepts program

    NASA Technical Reports Server (NTRS)

    Curran, Francis M.; Bennett, Gary L.; Frisbee, Robert H.; Sercel, Joel C.; Lapointe, Michael R.

    1992-01-01

    NASA Advanced Propulsion Concepts (APC) program for the development of long-term space propulsion system schemes is managed by both NASA-Lewis and the JPL and is tasked with the identification and conceptual development of high-risk/high-payoff configurations. Both theoretical and experimental investigations have been undertaken in technology areas deemed essential to the implementation of candidate concepts. These APC candidates encompass very high energy density chemical propulsion systems, advanced electric propulsion systems, and an antiproton-catalyzed nuclear propulsion concept. A development status evaluation is presented for these systems.

  14. Advanced technology application for combustion chamber concepts

    NASA Technical Reports Server (NTRS)

    Tygielski, Kathy S.

    1992-01-01

    NASA-Marshall is engaged in the development of an Advanced Main Combustion Chamber under the aegis of the Earth-to-Orbit Propulsion Technology Program. AMCC is to be a robust and highly reliable combustion-chamber prototype costing one-third as much as current designs of comparable performance; it will be associated with a reduction of fabrication time by one-half. Attention is presently given to the three component-manufacturing processes used: single-piece investment casting for the structural jacket and manifolds; vacuum plasma spraying, for the combustion liner, and an alternative, platelet-compounded liner.

  15. Aeroelastic stability of coupled flap-lag motion of hingeless helicopter blades at arbitrary advance ratios

    NASA Technical Reports Server (NTRS)

    Friedmann, P.; Silverthorn, L. J.

    1974-01-01

    Equations for large amplitude coupled flap-lag motion of a hingeless elastic helicopter blade in forward flight are derived. Only a torsionally rigid blade excited by quasi-steady aerodynamic loads is considered. The effects of reversed flow together with some new terms due to radial flow are included. Using Galerkin's method the spatial dependence is eliminated and the equations are linearized about a suitable equilibrium position. The resulting system of homogeneous periodic equations is solved using multivariable Floquet-Liapunov theory, and the transition matrix at the end of the period is evaluated by two separate methods. Computational efficiency of the two numerical methods is compared. Results illustrating the effects of forward flight and various important blade parameters on the stability boundaries are presented.

  16. Parametric cost analysis for advanced energy concepts

    SciTech Connect

    Not Available

    1983-10-01

    This report presents results of an exploratory study to develop parametric cost estimating relationships for advanced fossil-fuel energy systems. The first of two tasks was to develop a standard Cost Chart of Accounts to serve as a basic organizing framework for energy systems cost analysis. The second task included development of selected parametric cost estimating relationships (CERs) for individual elements (or subsystems) of a fossil fuel plant, nominally for the Solvent-Refined Coal (SRC) process. Parametric CERs are presented for the following elements: coal preparation, coal slurry preparation, dissolver (reactor); gasification; oxygen production; acid gas/CO/sub 2/ removal; shift conversion; cryogenic hydrogen recovery; and sulfur removal. While the nominal focus of the study was on the SRC process, each of these elements is found in other fossil fuel processes. Thus, the results of this effort have broader potential application. However, it should also be noted that the CERs presented in this report are based upon a limited data base. Thus, they are applicable over a limited range of values (of the independent variables) and for a limited set of specific technologies (e.g., the gasifier CER is for the multi-train, Koppers-Totzek process). Additional work is required to extend the range of these CERs. 16 figures, 13 tables.

  17. Advanced progress concepts for direct coal liquefaction

    SciTech Connect

    Anderson, R.; Derbyshire, F.; Givens, E.

    1995-09-01

    Given the low cost of petroleum crude, direct coal liquefaction is still not an economically viable process. The DOE objectives are to further reduce the cost of coal liquefaction to a more competitive level. In this project the primary focus is on the use of low-rank coal feedstocks. A particular strength is the use of process-derived liquids rather than model compound solvents. The original concepts are illustrated in Figure 1, where they are shown on a schematic of the Wilsonville pilot plant operation. Wilsonville operating data have been used to define a base case scenario using run {number_sign}263J, and Wilsonville process materials have been used in experimental work. The CAER has investigated: low severity CO pretreatment of coal for oxygen rejection, increasing coal reactivity and mg inhibiting the propensity for regressive reactions; the application of more active. Low-cost Fe and Mo dispersed catalysts; and the possible use of fluid coking for solids rejection and to generate an overhead product for recycle. CONSOL has investigated: oil agglomeration for coal ash rejection, for the possible rejection of ash in the recycled resid, and for catalyst addition and recovery; and distillate dewaxing to remove naphthenes and paraffins, and to generate an improved quality feed for recycle distillate hydrogenation. At Sandia, research has been concerned with the production of active hydrogen donor distillate solvent fractions produced by the hydrogenation of dewaxed distillates and by fluid coking via low severity reaction with H{sub 2}/CO/H{sub 2}O mixtures using hydrous metal oxide and other catalysts.

  18. Advanced Concepts for Underwater Acoustic Channel Modeling

    NASA Astrophysics Data System (ADS)

    Etter, P. C.; Haas, C. H.; Ramani, D. V.

    2014-12-01

    This paper examines nearshore underwater-acoustic channel modeling concepts and compares channel-state information requirements against existing modeling capabilities. This process defines a subset of candidate acoustic models suitable for simulating signal propagation in underwater communications. Underwater-acoustic communications find many practical applications in coastal oceanography, and networking is the enabling technology for these applications. Such networks can be formed by establishing two-way acoustic links between autonomous underwater vehicles and moored oceanographic sensors. These networks can be connected to a surface unit for further data transfer to ships, satellites, or shore stations via a radio-frequency link. This configuration establishes an interactive environment in which researchers can extract real-time data from multiple, but distant, underwater instruments. After evaluating the obtained data, control messages can be sent back to individual instruments to adapt the networks to changing situations. Underwater networks can also be used to increase the operating ranges of autonomous underwater vehicles by hopping the control and data messages through networks that cover large areas. A model of the ocean medium between acoustic sources and receivers is called a channel model. In an oceanic channel, characteristics of the acoustic signals change as they travel from transmitters to receivers. These characteristics depend upon the acoustic frequency, the distances between sources and receivers, the paths followed by the signals, and the prevailing ocean environment in the vicinity of the paths. Properties of the received signals can be derived from those of the transmitted signals using these channel models. This study concludes that ray-theory models are best suited to the simulation of acoustic signal propagation in oceanic channels and identifies 33 such models that are eligible candidates.

  19. Brush seal numerical simulation: Concepts and advances

    NASA Technical Reports Server (NTRS)

    Braun, M. J.; Kudriavtsev, V. V.

    1994-01-01

    The development of the brush seal is considered to be most promising among the advanced type seals that are presently in use in the high speed turbomachinery. The brush is usually mounted on the stationary portions of the engine and has direct contact with the rotating element, in the process of limiting the 'unwanted' leakage flows between stages, or various engine cavities. This type of sealing technology is providing high (in comparison with conventional seals) pressure drops due mainly to the high packing density (around 100 bristles/sq mm), and brush compliance with the rotor motions. In the design of modern aerospace turbomachinery leakage flows between the stages must be minimal, thus contributing to the higher efficiency of the engine. Use of the brush seal instead of the labyrinth seal reduces the leakage flow by one order of magnitude. Brush seals also have been found to enhance dynamic performance, cost less, and are lighter than labyrinth seals. Even though industrial brush seals have been successfully developed through extensive experimentation, there is no comprehensive numerical methodology for the design or prediction of their performance. The existing analytical/numerical approaches are based on bulk flow models and do not allow the investigation of the effects of brush morphology (bristle arrangement), or brushes arrangement (number of brushes, spacing between them), on the pressure drops and flow leakage. An increase in the brush seal efficiency is clearly a complex problem that is closely related to the brush geometry and arrangement, and can be solved most likely only by means of a numerically distributed model.

  20. Brush seal numerical simulation: Concepts and advances

    NASA Astrophysics Data System (ADS)

    Braun, M. J.; Kudriavtsev, V. V.

    1994-07-01

    The development of the brush seal is considered to be most promising among the advanced type seals that are presently in use in the high speed turbomachinery. The brush is usually mounted on the stationary portions of the engine and has direct contact with the rotating element, in the process of limiting the 'unwanted' leakage flows between stages, or various engine cavities. This type of sealing technology is providing high (in comparison with conventional seals) pressure drops due mainly to the high packing density (around 100 bristles/sq mm), and brush compliance with the rotor motions. In the design of modern aerospace turbomachinery leakage flows between the stages must be minimal, thus contributing to the higher efficiency of the engine. Use of the brush seal instead of the labyrinth seal reduces the leakage flow by one order of magnitude. Brush seals also have been found to enhance dynamic performance, cost less, and are lighter than labyrinth seals. Even though industrial brush seals have been successfully developed through extensive experimentation, there is no comprehensive numerical methodology for the design or prediction of their performance. The existing analytical/numerical approaches are based on bulk flow models and do not allow the investigation of the effects of brush morphology (bristle arrangement), or brushes arrangement (number of brushes, spacing between them), on the pressure drops and flow leakage. An increase in the brush seal efficiency is clearly a complex problem that is closely related to the brush geometry and arrangement, and can be solved most likely only by means of a numerically distributed model.

  1. Atmospheric fluidized bed combustion advanced concept system

    SciTech Connect

    Not Available

    1992-05-01

    DONLEE Technologies Inc. is developing with support of the US Department of Energy an advanced circulating fluidized bed technology known as the Vortex{trademark} Fluidized Bed Combustor (VFBC). The unique feature of the VFBC is the injection of a significant portion of the combustion air into the cyclone. Since as much as one-half of the total combustion air is injected into the cyclone, the cross-sectional area of the circulating fluidized bed is considerably smaller than typical circulating fluidized beds. The technology is being developed for two applications: Industrial-scale boilers ranging from 20,000 to 100,000 pounds per hour steam generating capacity; and two-stage combustion in which a substoichiometric Vortex Fluidized Bed Combustor (2VFBC) or precombustor is used to generate a combustible gas for use primarily in boiler retrofit applications. This Level II analysis of these two applications indicates that both have merit. An industrial-scale VFBC boiler (60,000 lb/hr of steam) is projected to be economically attractive with coal prices as high as $40 per ton and gas prices between $4 and $5 per thousand cubic feet. The payback time is between 3 and 4 years. The 2VFBC system was evaluated at three capacities of application: 20,000; 60,000 and 100,000 lb/hr of steam. The payback times for these three capacities are 4.5, 2.1 and 1.55 years, respectively. The 2VFBC has potential applications for retrofit of existing pulverized coal-fired boilers or as a new large (utility) boiler. Pressurized operation of the 2VFBC has considerable potential for combined cycle power generation applications. Experimental development of both applications is presented here to demonstrate the potential of these two technologies.

  2. Advanced Optical Burst Switched Network Concepts

    NASA Astrophysics Data System (ADS)

    Nejabati, Reza; Aracil, Javier; Castoldi, Piero; de Leenheer, Marc; Simeonidou, Dimitra; Valcarenghi, Luca; Zervas, Georgios; Wu, Jian

    In recent years, as the bandwidth and the speed of networks have increased significantly, a new generation of network-based applications using the concept of distributed computing and collaborative services is emerging (e.g., Grid computing applications). The use of the available fiber and DWDM infrastructure for these applications is a logical choice offering huge amounts of cheap bandwidth and ensuring global reach of computing resources [230]. Currently, there is a great deal of interest in deploying optical circuit (wavelength) switched network infrastructure for distributed computing applications that require long-lived wavelength paths and address the specific needs of a small number of well-known users. Typical users are particle physicists who, due to their international collaborations and experiments, generate enormous amounts of data (Petabytes per year). These users require a network infrastructures that can support processing and analysis of large datasets through globally distributed computing resources [230]. However, providing wavelength granularity bandwidth services is not an efficient and scalable solution for applications and services that address a wider base of user communities with different traffic profiles and connectivity requirements. Examples of such applications may be: scientific collaboration in smaller scale (e.g., bioinformatics, environmental research), distributed virtual laboratories (e.g., remote instrumentation), e-health, national security and defense, personalized learning environments and digital libraries, evolving broadband user services (i.e., high resolution home video editing, real-time rendering, high definition interactive TV). As a specific example, in e-health services and in particular mammography applications due to the size and quantity of images produced by remote mammography, stringent network requirements are necessary. Initial calculations have shown that for 100 patients to be screened remotely, the network

  3. Advanced beamed-energy and field propulsion concepts

    NASA Technical Reports Server (NTRS)

    Myrabo, L. N.

    1983-01-01

    Specific phenomena which might lead to major advances in payload, range and terminal velocity of very advanced vehicle propulsion are studied. The effort focuses heavily on advanced propulsion spinoffs enabled by current government-funded investigations in directed-energy technology: i.e., laser, microwave, and relativistic charged particle beams. Futuristic (post-year 2000) beamed-energy propulsion concepts which indicate exceptional promise are identified and analytically investigated. The concepts must be sufficiently developed to permit technical understanding of the physical processes involved, assessment of the enabling technologies, and evaluation of their merits over conventional systems. Propulsion concepts that can be used for manned and/or unmanned missions for purposes of solar system exploration, planetary landing, suborbital flight, transport to orbit, and escape are presented. Speculations are made on the chronology of milestones in beamed-energy propulsion development, such as in systems applications of defense, satellite orbit-raising, global aerospace transportation, and manned interplanetary carriers.

  4. Overview of an Advanced Hypersonic Structural Concept Test Program

    NASA Technical Reports Server (NTRS)

    Stephens, Craig A.; Hudson, Larry D.; Piazza, Anthony

    2007-01-01

    This viewgraph presentation provides an overview of hypersonics M&S advanced structural concepts development and experimental methods. The discussion on concepts development includes the background, task objectives, test plan, and current status of the C/SiC Ruddervator Subcomponent Test Article (RSTA). The discussion of experimental methods examines instrumentation needs, sensors of interest, and examples of ongoing efforts in the development of extreme environment sensors.

  5. Heuristics Applied in the Development of Advanced Space Mission Concepts

    NASA Technical Reports Server (NTRS)

    Nilsen, Erik N.

    1998-01-01

    Advanced mission studies are the first step in determining the feasibility of a given space exploration concept. A space scientist develops a science goal in the exploration of space. This may be a new observation method, a new instrument or a mission concept to explore a solar system body. In order to determine the feasibility of a deep space mission, a concept study is convened to determine the technology needs and estimated cost of performing that mission. Heuristics are one method of defining viable mission and systems architectures that can be assessed for technology readiness and cost. Developing a viable architecture depends to a large extent upon extending the existing body of knowledge, and applying it in new and novel ways. These heuristics have evolved over time to include methods for estimating technical complexity, technology development, cost modeling and mission risk in the unique context of deep space missions. This paper examines the processes involved in performing these advanced concepts studies, and analyzes the application of heuristics in the development of an advanced in-situ planetary mission. The Venus Surface Sample Return mission study provides a context for the examination of the heuristics applied in the development of the mission and systems architecture. This study is illustrative of the effort involved in the initial assessment of an advance mission concept, and the knowledge and tools that are applied.

  6. AREAL test facility for advanced accelerator and radiation source concepts

    NASA Astrophysics Data System (ADS)

    Tsakanov, V. M.; Amatuni, G. A.; Amirkhanyan, Z. G.; Aslyan, L. V.; Avagyan, V. Sh.; Danielyan, V. A.; Davtyan, H. D.; Dekhtiarov, V. S.; Gevorgyan, K. L.; Ghazaryan, N. G.; Grigoryan, B. A.; Grigoryan, A. H.; Hakobyan, L. S.; Haroutiunian, S. G.; Ivanyan, M. I.; Khachatryan, V. G.; Laziev, E. M.; Manukyan, P. S.; Margaryan, I. N.; Markosyan, T. M.; Martirosyan, N. V.; Mehrabyan, Sh. A.; Mkrtchyan, T. H.; Muradyan, L. Kh.; Nikogosyan, G. H.; Petrosyan, V. H.; Sahakyan, V. V.; Sargsyan, A. A.; Simonyan, A. S.; Toneyan, H. A.; Tsakanian, A. V.; Vardanyan, T. L.; Vardanyan, A. S.; Yeremyan, A. S.; Zakaryan, S. V.; Zanyan, G. S.

    2016-09-01

    Advanced Research Electron Accelerator Laboratory (AREAL) is a 50 MeV electron linear accelerator project with a laser driven RF gun being constructed at the CANDLE Synchrotron Research Institute. In addition to applications in life and materials sciences, the project aims as a test facility for advanced accelerator and radiation source concepts. In this paper, the AREAL RF photoinjector performance, the facility design considerations and its highlights in the fields of free electron laser, the study of new high frequency accelerating structures, the beam microbunching and wakefield acceleration concepts are presented.

  7. Blade Vibration Measurement System for Unducted Fans

    NASA Technical Reports Server (NTRS)

    Marscher, William

    2014-01-01

    With propulsion research programs focused on new levels of efficiency and noise reduction, two avenues for advanced gas turbine technology are emerging: the geared turbofan and ultrahigh bypass ratio fan engines. Both of these candidates are being pursued as collaborative research projects between NASA and the engine manufacturers. The high bypass concept from GE Aviation is an unducted fan that features a bypass ratio of over 30 along with the accompanying benefits in fuel efficiency. This project improved the test and measurement capabilities of the unducted fan blade dynamic response. In the course of this project, Mechanical Solutions, Inc. (MSI) collaborated with GE Aviation to (1) define the requirements for fan blade measurements; (2) leverage MSI's radar-based system for compressor and turbine blade monitoring; and (3) develop, validate, and deliver a noncontacting blade vibration measurement system for unducted fans.

  8. Preliminary design study of advanced composite blade and hub and nonmechanical control system for the tilt-rotor aircraft. Volume 2: Project planning data

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Project planning data for a rotor and control system procurement and testing program for modifications to the XV-15 tilt-rotor research demonstrator aircraft is presented. The design, fabrication, and installation of advanced composite blades compatible with the existing hub, an advanced composite hub, and a nonmechanical control system are required.

  9. Overview on NASA's Advanced Electric Propulsion Concepts Activities

    NASA Technical Reports Server (NTRS)

    Frisbee, Robert H.

    1999-01-01

    Advanced electric propulsion research activities are currently underway that seek to addresses feasibility issues of a wide range of advanced concepts, and may result in the development of technologies that will enable exciting new missions within our solar system and beyond. Each research activity is described in terms of the present focus and potential future applications. Topics include micro-electric thrusters, electrodynamic tethers, high power plasma thrusters and related applications in materials processing, variable specific impulse plasma thrusters, pulsed inductive thrusters, computational techniques for thruster modeling, and advanced electric propulsion missions and systems studies.

  10. Helicopter far-field acoustic levels as a function of reduced main-rotor advancing blade-tip Mach number

    NASA Astrophysics Data System (ADS)

    Mueller, Arnold W.; Smith, Charles D.; Lemasurier, Philip

    1990-07-01

    During the design of a helicopter, the weight, engine, rotor speed, and rotor geometry are given significant attention when considering the specific operations for which the helicopter will be used. However, the noise radiated from the helicopter and its relationship to the design variables is currently not well modeled with only a limited set of full-scale field test data to study. In general, limited field data have shown that reduced main-rotor advancing blade-tip Mach numbers result in reduced far-field noise levels. The status of a recent helicopter noise research project is reviewed. It is designed to provide flight experimental data which may be used to further understand helicopter main-rotor advancing blade-tip Mach number effects on far-field acoustic levels. Preliminary results are presented relative to tests conducted with a Sikorsky S-76A helicopter operating with both the rotor speed and the flight speed as the control variable. The rotor speed was operated within the range of 107 to 90 percent NR at nominal forward speeds of 35, 100, and 155 knots.

  11. Helicopter far-field acoustic levels as a function of reduced main-rotor advancing blade-tip Mach number

    NASA Technical Reports Server (NTRS)

    Mueller, Arnold W.; Smith, Charles D.; Lemasurier, Philip

    1990-01-01

    During the design of a helicopter, the weight, engine, rotor speed, and rotor geometry are given significant attention when considering the specific operations for which the helicopter will be used. However, the noise radiated from the helicopter and its relationship to the design variables is currently not well modeled with only a limited set of full-scale field test data to study. In general, limited field data have shown that reduced main-rotor advancing blade-tip Mach numbers result in reduced far-field noise levels. The status of a recent helicopter noise research project is reviewed. It is designed to provide flight experimental data which may be used to further understand helicopter main-rotor advancing blade-tip Mach number effects on far-field acoustic levels. Preliminary results are presented relative to tests conducted with a Sikorsky S-76A helicopter operating with both the rotor speed and the flight speed as the control variable. The rotor speed was operated within the range of 107 to 90 percent NR at nominal forward speeds of 35, 100, and 155 knots.

  12. Advancing Your Career: Concepts of Professional Nursing. Second Edition.

    ERIC Educational Resources Information Center

    Kearney, Rose

    This textbook, intended for registered nurses (RN's) returning to school, is designed to provide practicing RN's with professional concepts to advance their careers. The book contains 22 chapters organized in five sections. Each chapter includes chapter objectives, key terms, key points, chapter exercises, references, and a bibliography. Section I…

  13. Prediction of helicopter rotor discrete frequency noise: A computer program incorporating realistic blade motions and advanced acoustic formulation

    NASA Technical Reports Server (NTRS)

    Brentner, K. S.

    1986-01-01

    A computer program has been developed at the Langley Research Center to predict the discrete frequency noise of conventional and advanced helicopter rotors. The program, called WOPWOP, uses the most advanced subsonic formulation of Farassat that is less sensitive to errors and is valid for nearly all helicopter rotor geometries and flight conditions. A brief derivation of the acoustic formulation is presented along with a discussion of the numerical implementation of the formulation. The computer program uses realistic helicopter blade motion and aerodynamic loadings, input by the user, for noise calculation in the time domain. A detailed definition of all the input variables, default values, and output data is included. A comparison with experimental data shows good agreement between prediction and experiment; however, accurate aerodynamic loading is needed.

  14. Advanced laser sensing receiver concepts based on FPA technology.

    SciTech Connect

    Jacobson, P. L.; Petrin, R. R.; Jolin, J. L.; Foy, B. R.; Lowrance, J. L.; Renda, G.

    2002-01-01

    The ultimate performance of any remote sensor is ideally governed by the hardware signal-to-noise capability and allowed signal-averaging time. In real-world scenarios, this may not be realizable and the limiting factors may suggest the need for more advanced capabilities. Moving from passive to active remote sensors offers the advantage of control over the illumination source, the laser. Added capabilities may include polarization discrimination, instantaneous imaging, range resolution, simultaneous multi-spectral measurement, or coherent detection. However, most advanced detection technology has been engineered heavily towards the straightforward passive sensor requirements, measuring an integrated photon flux. The need for focal plane array technology designed specifically for laser sensing has been recognized for some time, but advances have only recently made the engineering possible. This paper will present a few concepts for laser sensing receiver architectures, the driving specifications behind those concepts, and test/modeling results of such designs.

  15. Test Rig for Evaluating Active Turbine Blade Tip Clearance Control Concepts

    NASA Technical Reports Server (NTRS)

    Lattime, Scott B.; Steinetz, Bruce M.; Robbie, Malcolm G.; Erker, Arthur H.

    2004-01-01

    The objectives of the research presented in this viewgraph presentation are to 1) Design a mechanical ACC system for HPT tip seal clearance management; 2) Design a test rig to evaluate ACC system concepts. We have focused our efforts on designing mechanical ACC systems that articulate the seal shroud via mechanical linkages connected to actuators that reside outside the extreme environment of the HPT. We opted for this style of design due to a lack of high temperature/low profile actuators that are presently available. We have also selected multiple hydraulic actuators for this first generation ACC system. Fuel-draulic actuators are already a well established technology.

  16. MSFC Advanced Concepts Office and the Iterative Launch Vehicle Concept Method

    NASA Technical Reports Server (NTRS)

    Creech, Dennis

    2011-01-01

    This slide presentation reviews the work of the Advanced Concepts Office (ACO) at Marshall Space Flight Center (MSFC) with particular emphasis on the method used to model launch vehicles using INTegrated ROcket Sizing (INTROS), a modeling system that assists in establishing the launch concept design, and stage sizing, and facilitates the integration of exterior analytic efforts, vehicle architecture studies, and technology and system trades and parameter sensitivities.

  17. Advanced grid-stiffened composite shells for applications in heavy-lift helicopter rotor blade spars

    NASA Astrophysics Data System (ADS)

    Narayanan Nampy, Sreenivas

    Modern rotor blades are constructed using composite materials to exploit their superior structural performance compared to metals. Helicopter rotor blade spars are conventionally designed as monocoque structures. Blades of the proposed Heavy Lift Helicopter are envisioned to be as heavy as 800 lbs when designed using the monocoque spar design. A new and innovative design is proposed to replace the conventional spar designs with light weight grid-stiffened composite shell. Composite stiffened shells have been known to provide excellent strength to weight ratio and damage tolerance with an excellent potential to reduce weight. Conventional stringer--rib stiffened construction is not suitable for rotor blade spars since they are limited in generating high torsion stiffness that is required for aeroelastic stability of the rotor. As a result, off-axis (helical) stiffeners must be provided. This is a new design space where innovative modeling techniques are needed. The structural behavior of grid-stiffened structures under axial, bending, and torsion loads, typically experienced by rotor blades need to be accurately predicted. The overall objective of the present research is to develop and integrate the necessary design analysis tools to conduct a feasibility study in employing grid-stiffened shells for heavy-lift rotor blade spars. Upon evaluating the limitations in state-of-the-art analytical models in predicting the axial, bending, and torsion stiffness coefficients of grid and grid-stiffened structures, a new analytical model was developed. The new analytical model based on the smeared stiffness approach was developed employing the stiffness matrices of the constituent members of the grid structure such as an arch, helical, or straight beam representing circumferential, helical, and longitudinal stiffeners. This analysis has the capability to model various stiffening configurations such as angle-grid, ortho-grid, and general-grid. Analyses were performed using an

  18. Systems analysis and futuristic designs of advanced biofuel factory concepts.

    SciTech Connect

    Chianelli, Russ; Leathers, James; Thoma, Steven George; Celina, Mathias Christopher; Gupta, Vipin P.

    2007-10-01

    The U.S. is addicted to petroleum--a dependency that periodically shocks the economy, compromises national security, and adversely affects the environment. If liquid fuels remain the main energy source for U.S. transportation for the foreseeable future, the system solution is the production of new liquid fuels that can directly displace diesel and gasoline. This study focuses on advanced concepts for biofuel factory production, describing three design concepts: biopetroleum, biodiesel, and higher alcohols. A general schematic is illustrated for each concept with technical description and analysis for each factory design. Looking beyond current biofuel pursuits by industry, this study explores unconventional feedstocks (e.g., extremophiles), out-of-favor reaction processes (e.g., radiation-induced catalytic cracking), and production of new fuel sources traditionally deemed undesirable (e.g., fusel oils). These concepts lay the foundation and path for future basic science and applied engineering to displace petroleum as a transportation energy source for good.

  19. Development of two rhenium- containing superalloys for single- crystal blade and directionally solidified vane applications in advanced turbine engines

    NASA Astrophysics Data System (ADS)

    Harris, K.; Erickson, G. L.; Sikkenga, S. L.; Brentnall, W. D.; Aurrecoechea, J. M.; Kubarych, K. G.

    1993-08-01

    A team approach involving several turbine engine companies using the concepts of simultaneous engi-neering has been used to successfully develop CMSX-4 ® alloy for turbine blade applications. CMSX-4 al-loy is a second-generation, single-crystal cast nickel-base superalloy containing 3% Re and approximately 70% volume fraction of γ. The high level of balanced properties determined by labora-tory evaluation has been confirmed during field testing of the Solarγ Mars T-14000 industrial gas turbine with CMSX-4 single-crystal (SX) blades in both the coated and bare condition. A similar collaborative ap-proach has resulted in the successful development of CM 186 LCγ alloy for complex, directionally solidi-fied (DS) columnar grain vane segments. CM 186 LC alloy is a second-generation DS columnar grain cast nickel-base superalloy containing 3% Re and approximately 65% volume fraction of γ. Excellent com-ponent producibility and quality is demonstrated. Turbine engine testing is scheduled to commence by the end of 1993.

  20. Validation Database Based Thermal Analysis of an Advanced RPS Concept

    NASA Technical Reports Server (NTRS)

    Balint, Tibor S.; Emis, Nickolas D.

    2006-01-01

    Advanced RPS concepts can be conceived, designed and assessed using high-end computational analysis tools. These predictions may provide an initial insight into the potential performance of these models, but verification and validation are necessary and required steps to gain confidence in the numerical analysis results. This paper discusses the findings from a numerical validation exercise for a small advanced RPS concept, based on a thermal analysis methodology developed at JPL and on a validation database obtained from experiments performed at Oregon State University. Both the numerical and experimental configurations utilized a single GPHS module enabled design, resembling a Mod-RTG concept. The analysis focused on operating and environmental conditions during the storage phase only. This validation exercise helped to refine key thermal analysis and modeling parameters, such as heat transfer coefficients, and conductivity and radiation heat transfer values. Improved understanding of the Mod-RTG concept through validation of the thermal model allows for future improvements to this power system concept.

  1. Blade System Design Studies Volume I: Composite Technologies for Large Wind Turbine Blades

    NASA Astrophysics Data System (ADS)

    Griffin, D.

    2002-07-01

    As part of the U.S. Department of Energy's Wind Partnerships for Advanced Component Technologies (WindPACT) program, Global Energy Concepts LLC (GEC) is performing a study concerning innovations in materials, processes and structural configurations for application to wind turbine blades in the multi-megawatt range. The project team for this work includes experts in all areas of wind turbine blade design, analysis, manufacture, and testing. Constraints to cost-effective scaling-up of the current commercial blade designs and manufacturing methods are identified, including self-gravity loads, transportation, and environmental considerations. A trade-off study is performed to evaluate the incremental changes in blade cost, weight, and stiffness for a wide range of composite materials, fabric types, and manufacturing processes.

  2. THE 13TH ADVANCED ACCELERATOR CONCEPTS WORKSHOP (AAC'8)

    SciTech Connect

    Leemans, Wim; Schroder, Carl B.; Esarey, Eric

    2008-07-15

    The Thirteenth Workshop on Advanced Accelerator Concepts (AAC) was held from July 27 to August 2, 2008 at the Chaminade Conference Center in Santa Cruz, California, USA, organized by the Lawrence Berkeley National Laboratory and the University of California at Berkeley. There were unprecedented levels of interest in the 2008 AAC Workshop, and participation was by invitation, with 215 workshop attendees, including 58 students. Reflecting the world-wide growth of the advanced accelerator community, there was significant international participation, with participants from twelve countries attending.

  3. NASA advanced turboprop research and concept validation program

    NASA Technical Reports Server (NTRS)

    Whitlow, John B., Jr.; Sievers, G. Keith

    1988-01-01

    NASA has determined by experimental and analytical effort that use of advanced turboprop propulsion instead of the conventional turbofans in the older narrow-body airline fleet could reduce fuel consumption for this type of aircraft by up to 50 percent. In cooperation with industry, NASA has defined and implemented an Advanced Turboprop (ATP) program to develop and validate the technology required for these new high-speed, multibladed, thin, swept propeller concepts. This paper presents an overview of the analysis, model-scale test, and large-scale flight test elements of the program together with preliminary test results, as available.

  4. Selected advanced aerodynamic and active control concepts development

    NASA Technical Reports Server (NTRS)

    1980-01-01

    A summary is presented of results obtained during analysis, design and test activities on six selected technical tasks directed at exploratory improvement of fuel efficiency for new and derivative transports. The work included investigations into the potential offered by natural laminar flow, improved surface coatings and advanced high lift concepts. Similar investigations covering optimum low-energy flight path control, integrated application of active controls and evaluation of primary flight control systems reliability and maintenance are also summarized. Recommendations are included for future work needed to exploit potential advancements.

  5. Blade-Mounted Flap Control for BVI Noise Reduction Proof-of-Concept Test

    NASA Technical Reports Server (NTRS)

    Dawson, Seth; Hassan, Ahmed; Straub, Friedrich; Tadghighi, Hormoz

    1995-01-01

    This report describes a wind tunnel test of the McDonnell Douglas Helicopter Systems (MDHS) Active Flap Model Rotor at the NASA Langley 14- by 22-Foot Subsonic Tunnel. The test demonstrated that BVI noise reductions and vibration reductions were possible with the use of an active flap. Aerodynamic results supported the acoustic data trends, showing a reduction in the strength of the tip vortex with the deflection of the flap. Acoustic results showed that the flap deployment, depending on the peak deflection angle and azimuthal shift in its deployment schedule, can produce BVI noise reductions as much as 6 dB on the advancing and retreating sides. The noise reduction was accompanied by an increase in low frequency harmonic noise and high frequency broadband noise. A brief assessment of the effect of the flap on vibration showed that significant reductions were possible. The greatest vibration reductions (as much as 76%) were found in the four per rev pitching moment at the hub. Performance improvement cam results were inconclusive, as the improvements were predicted to be smaller than the resolution of the rotor balance.

  6. Advanced fuel cell concepts for future NASA missions

    NASA Astrophysics Data System (ADS)

    Stedman, J. K.

    1987-09-01

    Studies of primary fuel cells for advanced all electric shuttle type vehicles show an all fuel cell power system with peak power capability of 100's of kW to be potentially lighter and have lower life cycle costs than a hybrid system using advanced H2O2 APU's for peak power and fuel cells for low power on orbit. Fuel cell specific weights of 1 to 3 lb/kW, a factor of 10 improvement over the orbiter power plant, are projected for the early 1990's. For satellite applications, a study to identify high performance regenerative hydrogen oxygen fuel cell concepts for geosynchronous orbit was completed. Emphasis was placed on concepts with the potential for high energy density (Wh/lb) and passive means for water and heat management to maximize system reliability. Both alkaline electrolyte and polymer membrane fuel cells were considered.

  7. Advanced fuel cell concepts for future NASA missions

    NASA Technical Reports Server (NTRS)

    Stedman, J. K.

    1987-01-01

    Studies of primary fuel cells for advanced all electric shuttle type vehicles show an all fuel cell power system with peak power capability of 100's of kW to be potentially lighter and have lower life cycle costs than a hybrid system using advanced H2O2 APU's for peak power and fuel cells for low power on orbit. Fuel cell specific weights of 1 to 3 lb/kW, a factor of 10 improvement over the orbiter power plant, are projected for the early 1990's. For satellite applications, a study to identify high performance regenerative hydrogen oxygen fuel cell concepts for geosynchronous orbit was completed. Emphasis was placed on concepts with the potential for high energy density (Wh/lb) and passive means for water and heat management to maximize system reliability. Both alkaline electrolyte and polymer membrane fuel cells were considered.

  8. Development of environmentally advanced hydropower turbine system design concepts

    SciTech Connect

    Franke, G.F.; Webb, D.R.; Fisher, R.K. Jr.

    1997-08-01

    A team worked together on the development of environmentally advanced hydro turbine design concepts to reduce hydropower`s impact on the environment, and to improve the understanding of the technical and environmental issues involved, in particular, with fish survival as a result of their passage through hydro power sites. This approach brought together a turbine design and manufacturing company, biologists, a utility, a consulting engineering firm and a university research facility, in order to benefit from the synergy of diverse disciplines. Through a combination of advanced technology and engineering analyses, innovative design concepts adaptable to both new and existing hydro facilities were developed and are presented. The project was divided into 4 tasks. Task 1 investigated a broad range of environmental issues and how the issues differed throughout the country. Task 2 addressed fish physiology and turbine physics. Task 3 investigated individual design elements needed for the refinement of the three concept families defined in Task 1. Advanced numerical tools for flow simulation in turbines are used to quantify characteristics of flow and pressure fields within turbine water passageways. The issues associated with dissolved oxygen enhancement using turbine aeration are presented. The state of the art and recent advancements of this technology are reviewed. Key elements for applying turbine aeration to improve aquatic habitat are discussed and a review of the procedures for testing of aerating turbines is presented. In Task 4, the results of the Tasks were assembled into three families of design concepts to address the most significant issues defined in Task 1. The results of the work conclude that significant improvements in fish passage survival are achievable.

  9. The MOD-1 steel blade

    NASA Technical Reports Server (NTRS)

    Vanbronkhorst, J.

    1979-01-01

    The design, development, fabrication, testing, and transport of two 100 foot metal blades for the MOD-1 WTS are summarized. Because the metal blade design was started late in the MOD-1 system development, many of the design requirements (allocations) were restrictive for the metal blade concept, particularly the maximum weight requirement. The design solutions required to achieve the weight goal resulted in a labor intensive (expensive) fabrication, particularly for a quantity of only two blades manufactured using minimal tooling.

  10. Structural Configuration Systems Analysis for Advanced Aircraft Fuselage Concepts

    NASA Technical Reports Server (NTRS)

    Mukhopadhyay, Vivek; Welstead, Jason R.; Quinlan, Jesse R.; Guynn, Mark D.

    2016-01-01

    Structural configuration analysis of an advanced aircraft fuselage concept is investigated. This concept is characterized by a double-bubble section fuselage with rear mounted engines. Based on lessons learned from structural systems analysis of unconventional aircraft, high-fidelity finite-element models (FEM) are developed for evaluating structural performance of three double-bubble section configurations. Structural sizing and stress analysis are applied for design improvement and weight reduction. Among the three double-bubble configurations, the double-D cross-section fuselage design was found to have a relatively lower structural weight. The structural FEM weights of these three double-bubble fuselage section concepts are also compared with several cylindrical fuselage models. Since these fuselage concepts are different in size, shape and material, the fuselage structural FEM weights are normalized by the corresponding passenger floor area for a relative comparison. This structural systems analysis indicates that an advanced composite double-D section fuselage may have a relative structural weight ratio advantage over a conventional aluminum fuselage. Ten commercial and conceptual aircraft fuselage structural weight estimates, which are empirically derived from the corresponding maximum takeoff gross weight, are also presented and compared with the FEM- based estimates for possible correlation. A conceptual full vehicle FEM model with a double-D fuselage is also developed for preliminary structural analysis and weight estimation.

  11. Design and analysis of advanced flight planning concepts

    NASA Technical Reports Server (NTRS)

    Sorensen, John A.

    1987-01-01

    The objectives of this continuing effort are to develop and evaluate new algorithms and advanced concepts for flight management and flight planning. This includes the minimization of fuel or direct operating costs, the integration of the airborne flight management and ground-based flight planning processes, and the enhancement of future traffic management systems design. Flight management (FMS) concepts are for on-board profile computation and steering of transport aircraft in the vertical plane between a city pair and along a given horizontal path. Flight planning (FPS) concepts are for the pre-flight ground based computation of the three-dimensional reference trajectory that connects the city pair and specifies the horizontal path, fuel load, and weather profiles for initializing the FMS. As part of these objectives, a new computer program called EFPLAN has been developed and utilized to study advanced flight planning concepts. EFPLAN represents an experimental version of an FPS. It has been developed to generate reference flight plans compatible as input to an FMS and to provide various options for flight planning research. This report describes EFPLAN and the associated research conducted in its development.

  12. Advancement of proprotor technology. Task 1: Design study summary. [aerodynamic concept of minimum size tilt proprotor research aircraft

    NASA Technical Reports Server (NTRS)

    1969-01-01

    A tilt-proprotor proof-of-concept aircraft design study has been conducted. The results are presented. The ojective of the contract is to advance the state of proprotor technology through design studies and full-scale wind-tunnel tests. The specific objective is to conduct preliminary design studies to define a minimum-size tilt-proprotor research aircraft that can perform proof-of-concept flight research. The aircraft that results from these studies is a twin-engine, high-wing aircraft with 25-foot, three-bladed tilt proprotors mounted on pylons at the wingtips. Each pylon houses a Pratt and Whitney PT6C-40 engine with a takeoff rating of 1150 horsepower. Empty weight is estimated at 6876 pounds. The normal gross weight is 9500 pounds, and the maximum gross weight is 12,400 pounds.

  13. Composite Structure Modeling and Analysis of Advanced Aircraft Fuselage Concepts

    NASA Technical Reports Server (NTRS)

    Mukhopadhyay, Vivek; Sorokach, Michael R.

    2015-01-01

    NASA Environmentally Responsible Aviation (ERA) project and the Boeing Company are collabrating to advance the unitized damage arresting composite airframe technology with application to the Hybrid-Wing-Body (HWB) aircraft. The testing of a HWB fuselage section with Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) construction is presently being conducted at NASA Langley. Based on lessons learned from previous HWB structural design studies, improved finite-element models (FEM) of the HWB multi-bay and bulkhead assembly are developed to evaluate the performance of the PRSEUS construction. In order to assess the comparative weight reduction benefits of the PRSEUS technology, conventional cylindrical skin-stringer-frame models of a cylindrical and a double-bubble section fuselage concepts are developed. Stress analysis with design cabin-pressure load and scenario based case studies are conducted for design improvement in each case. Alternate analysis with stitched composite hat-stringers and C-frames are also presented, in addition to the foam-core sandwich frame and pultruded rod-stringer construction. The FEM structural stress, strain and weights are computed and compared for relative weight/strength benefit assessment. The structural analysis and specific weight comparison of these stitched composite advanced aircraft fuselage concepts demonstrated that the pressurized HWB fuselage section assembly can be structurally as efficient as the conventional cylindrical fuselage section with composite stringer-frame and PRSEUS construction, and significantly better than the conventional aluminum construction and the double-bubble section concept.

  14. Measurement of Unsteady Blade Surface Pressure on a Single Rotation Large Scale Advanced Prop-fan with Angular and Wake Inflow at Mach Numbers from 0.02 to 0.70

    NASA Technical Reports Server (NTRS)

    Bushnell, P.; Gruber, M.; Parzych, D.

    1988-01-01

    Unsteady blade surface pressure data for the Large-Scale Advanced Prop-Fan (LAP) blade operation with angular inflow, wake inflow and uniform flow over a range of inflow Mach numbers of 0.02 to 0.70 is provided. The data are presented as Fourier coefficients for the first 35 harmonics of shaft rotational frequency. Also presented is a brief discussion of the unsteady blade response observed at takeoff and cruise conditions with angular and wake inflow.

  15. Blade Manufacturing Improvement: Remote Blade Manufacturing Demonstration

    SciTech Connect

    ASHWILL, THOMAS D.

    2003-05-01

    The objective of this program was to investigate manufacturing improvements for wind turbine blades. The program included a series of test activities to evaluate the strength, deflection, performance, and loading characteristics of the prototype blades. The original contract was extended in order to continue development of several key blade technologies identified in the project. The objective of the remote build task was to demonstrate the concept of manufacturing wind turbine blades at a temporary manufacturing facility in a rural environment. TPI Composites successfully completed a remote manufacturing demonstration in which four blades were fabricated. The remote demonstration used a manufacturing approach which relied upon material ''kits'' that were organized in the factory and shipped to the site. Manufacturing blades at the wind plant site presents serious logistics difficulties and does not appear to be the best approach. A better method appears to be regional manufacturing facilities, which will eliminate most of the transportation cost, without incurring the logistical problems associated with fabrication directly onsite. With this approach the remote facilities would use commonly available industrial infrastructure such as enclosed workbays, overhead cranes, and paved staging areas. Additional fatigue testing of the M20 root stud design was completed with good results. This design provides adhesive bond strength under fatigue loading that exceeds that of the fastener. A new thru-stud bonding concept was developed for the M30 stud design. This approach offers several manufacturing advantages; however, the test results were inconclusive.

  16. New Developments in the Simulation of Advanced Accelerator Concepts

    SciTech Connect

    Bruhwiler, David L.; Cary, John R.; Cowan, Benjamin M.; Paul, Kevin; Mullowney, Paul J.; Messmer, Peter; Geddes, Cameron G. R.; Esarey, Eric; Cormier-Michel, Estelle; Leemans, Wim; Vay, Jean-Luc

    2009-01-22

    Improved computational methods are essential to the diverse and rapidly developing field of advanced accelerator concepts. We present an overview of some computational algorithms for laser-plasma concepts and high-brightness photocathode electron sources. In particular, we discuss algorithms for reduced laser-plasma models that can be orders of magnitude faster than their higher-fidelity counterparts, as well as important on-going efforts to include relevant additional physics that has been previously neglected. As an example of the former, we present 2D laser wakefield accelerator simulations in an optimal Lorentz frame, demonstrating >10 GeV energy gain of externally injected electrons over a 2 m interaction length, showing good agreement with predictions from scaled simulations and theory, with a speedup factor of {approx}2,000 as compared to standard particle-in-cell.

  17. New Developments in the Simulation of Advanced Accelerator Concepts

    SciTech Connect

    Paul, K.; Cary, J.R.; Cowan, B.; Bruhwiler, D.L.; Geddes, C.G.R.; Mullowney, P.J.; Messmer, P.; Esarey, E.; Cormier-Michel, E.; Leemans, W.P.; Vay, J.-L.

    2008-09-10

    Improved computational methods are essential to the diverse and rapidly developing field of advanced accelerator concepts. We present an overview of some computational algorithms for laser-plasma concepts and high-brightness photocathode electron sources. In particular, we discuss algorithms for reduced laser-plasma models that can be orders of magnitude faster than their higher-fidelity counterparts, as well as important on-going efforts to include relevant additional physics that has been previously neglected. As an example of the former, we present 2D laser wakefield accelerator simulations in an optimal Lorentz frame, demonstrating>10 GeV energy gain of externally injected electrons over a 2 m interaction length, showing good agreement with predictions from scaled simulations and theory, with a speedup factor of ~;;2,000 as compared to standard particle-in-cell.

  18. A system concept for an advanced vehicle control system

    SciTech Connect

    Mackey, D.E.; Mackey, W.F. Jr.; Mackey, W.F.

    1996-12-01

    This paper explores a system concept for an Advanced Vehicle Control System (AVCS). The progression of highway design and construction has resulted from an evolution of technologies, inventions, organizational creations, and legislative acts supporting the development of a national interstate transportation system. Until now, highway design and construction has been the domain of civil engineers concerned with highway structures, materials loading, traffic patterns, and supporting facilities. However, the growing need for intelligent vehicle-highway systems (IVHS) requires that traditional civil engineering disciplines be integrated with computers, communications, and eventually fully automated vehicles. This paper`s thesis suggests that the complex highway transportation of the late 20th century and the 21st century can benefit from the collaboration of systems engineers and civil engineers. This paper identifies and prototypes an AVCS concept with roadside computers controlling the lateral and longitudinal movements of a vehicle.

  19. Advanced launch vehicle system concepts: An historical overview

    SciTech Connect

    Ehrlich, C.F. Jr.

    1997-01-01

    Many studies leading to advanced launch vehicle system concepts have been undertaken during the years leading to the Space Shuttle development and since it was started. All of these have focused on nebulous and wide-ranging mission requirements. As a result, many launch system concepts have been defined, each addressing a different mission, yielding a wide range of points of departure once the {open_quotes}real{close_quotes} mission, or missions, have been identified. Future studies have this database available from which to depart once the {open_quotes}real{close_quotes} next generation mission is defined. This paper discusses some of the main issues surrounding the development of future systems. This subject really addresses the three principal requirements needed to be resolved for these systems to come into being: system architecture{emdash}what does the system look like and what is its makeup?, technologies{emdash}what are the technologies required to make the new system a successful venture and meet the requirements set forth in the mission statement?, and finally, the mission{emdash}what do we need to do and when?. The principal focus here will be on the past studies reviewing past concepts which address particular aspects of potential mission requirements with technology development and concepts discussed as we go along. {copyright} {ital 1997 American Institute of Physics.}

  20. Advanced launch vehicle system concepts: An historical overview

    NASA Astrophysics Data System (ADS)

    Ehrlich, Carl F.

    1997-01-01

    Many studies leading to advanced launch vehicle system concepts have been undertaken during the years leading to the Space Shuttle development and since it was started. All of these have focused on nebulous and wide-ranging mission requirements. As a result, many launch system concepts have been defined, each addressing a different mission, yielding a wide range of points of departure once the "real" mission, or missions, have been identified. Future studies have this database available from which to depart once the "real" next generation mission is defined. This paper discusses some of the main issues surrounding the development of future systems. This subject really addresses the three principal requirements needed to be resolved for these systems to come into being: system architecture—what does the system look like and what is its makeup?, technologies—what are the technologies required to make the new system a successful venture and meet the requirements set forth in the mission statement?, and finally, the mission—what do we need to do and when?. The principal focus here will be on the past studies reviewing past concepts which address particular aspects of potential mission requirements with technology development and concepts discussed as we go along.

  1. Advanced liquid oxygen (LO2) propellant conditioning concept testing

    NASA Technical Reports Server (NTRS)

    Perry, G. L. E.; Suter, J. D.; Turner, S. G.

    1995-01-01

    Advanced methods of liquid oxygen (LO2) propellant conditioning were studied as part of an effort for increasing reliability and operability while reducing cost of future heavy lift launch vehicles. The most promising conditioning concept evaluated was no-bleed (passive recirculation) followed by low-bleed, helium injection, and use of a recirculation line. Full-scale cryogenic testing was performed with a sloped feedline test article to validate models of behavior of LO2 in the feedline and to prove no-bleed feasibility. Test data are also intended to help generate design guidelines for the development of a main propulsion system feed duct. A design-of-experiments matrix of over 100 tests was developed to test all four propellant conditioning concepts and the impact of design parameters on the concepts. Liquid nitrogen was used as the test fluid. The work for this project was conducted from October 1992 through January 1994 at the hydrogen cold flow facility of the west test area of MSFC. Test data have shown that satisfactory temperatures are being obtained for the no-bleed conditioning concept.

  2. Containment of composite fan blades

    NASA Technical Reports Server (NTRS)

    Coppa, A. P.; Stotler, C. L.

    1977-01-01

    The development of containment concepts for use with large composite fan blades, taking into account the frangible nature of composite blades is considered. Aspects of the development program include; (1) an analysis to predict the interaction between a failed fan blade and the blade containment structure; (2) scaling factors to allow impact testing using subscale containment rings and simulated blades; (3) the design and fabrication of containment systems for further evaluation in a rotating rig test facility; (4) evaluate the test data against the analytically predicted results; and (5) determine overall systems weights and design characteristics of a composite fan stage installation and compare to the requirements of an equivalent titanium fan blade system. Progress in the blade impact penetration tests and the design and fabrication of blade containment systems is reported.

  3. Aeronautical technology 2000 - A projection of advanced vehicle concepts

    NASA Technical Reports Server (NTRS)

    Rosen, C. C., III; Burger, R. J.; Sigalla, A.

    1984-01-01

    At the request of NASA and under the aegis of the National Research Council, representatives from industry, academic institutions and government have participated in a workshop to consider opportunities for the exploitation of aircraft technology in such fields as aerodynamics, materials, structures, guidance, navigation and control, human factors, propulsion, computers and data processing, and systems integration. Attention is given to the advanced vehicle concepts that have emerged for possible year-2000 implementation, which encompass such diverse aircraft types as supersonic transports, hypersonic airliners, missiles, and interceptors, transatmospheric vehicles, next-generation space shuttles, subsonic transports and attack aircraft, advanced helicopter, tilt-rotor VTOL configurations, and solar- and microwave beam-powered extremely high altitude aircraft.

  4. Characterization of mechanical properties of aluminized coatings in advanced gas turbine blades using a small punch method

    SciTech Connect

    Sugita, Y.; Ito, M.; Sakurai, S.; Bloomer, T.E.; Kameda, J. |

    1997-04-01

    Advanced technologies of superalloy casting and coatings enable one to enhance the performance of combined cycle gas turbines for electric power generation by increasing the firing temperature. This paper describes examination of the microstructure/composition and mechanical properties (22--950 C) in aluminized CoCrAlY coatings of advanced gas turbine blades using scanning Auger microprobe and a small punch (SP) testing method. Aluminized coatings consisted of layered structure divided into four regimes: (1) Al enriched and Cr depleted region, (2) Al and Cr graded region, (3) fine grained microstructure with a mixture of Al and Cr enriched phases and (4) Ni/Co interdiffusion zone adjacent to the interface. SP specimens were prepared in order that the specimen surface would be located in the various coating regions. SP tests indicated strong dependence of the fracture properties on the various coatings regimes. Coatings 1 and 2 with very high microhardness showed much easier formation of brittle cracks in a wide temperature range, compared to coatings 3 and 4 although the coating 2 had ductility improvement at 950 C. The coating 3 had lower room temperature ductility than the coating 4. However, the ductility in the coating 3 exceeded that in the region 4 above 730 C due to a precipitous ductility increase. The integrity of aluminized coatings while in-service is discussed in light of the variation of the low cycle fatigue life as well as the ductility in the layered structure.

  5. Advance ratio effects on the flow structure and unsteadiness of the dynamic-stall vortex of a rotating blade in steady forward flight

    NASA Astrophysics Data System (ADS)

    Raghav, Vrishank; Komerath, Narayanan

    2015-02-01

    The effect of advance ratio on the flow structures above a rotor blade in dynamic-stall is studied using stereoscopic particle image velocimetry. The dynamic-stall vortex shows a significant velocity component in its core, implying a helical structure progressing radially outboard. In addition, a dual-vortical structure was observed at inboard locations only at high advance ratios. The radial velocity attenuates at outboard locations, in contrast to the expected increase with centripetal acceleration. This attenuation is accompanied by an increase in unsteadiness of the vortex. The unsteadiness shows a low-frequency cycle-to-cycle variation despite steady freestream conditions and phase-locked blade tracking. Proper orthogonal decomposition analysis of the dominant flow mode confirms the unsteady behavior of the leading-edge vortex. The dependence on advance ratio is used to relate the unsteadiness of the dynamic-stall vortex to Coriolis effects.

  6. Generic Repository Concepts and Thermal Analysis for Advanced Fuel Cycles

    SciTech Connect

    Hardin, Ernest; Blink, James; Carter, Joe; Massimiliano, Fratoni; Greenberg, Harris; Howard, Rob L

    2011-01-01

    The current posture of the used nuclear fuel management program in the U.S. following termination of the Yucca Mountain Project, is to pursue research and development (R&D) of generic (i.e., non-site specific) technologies for storage, transportation and disposal. Disposal R&D is directed toward understanding and demonstrating the performance of reference geologic disposal concepts selected to represent the current state-of-the-art in geologic disposal. One of the principal constraints on waste packaging and emplacement in a geologic repository is management of the waste-generated heat. This paper describes the selection of reference disposal concepts, and thermal management strategies for waste from advanced fuel cycles. A geologic disposal concept for spent nuclear fuel (SNF) or high-level waste (HLW) consists of three components: waste inventory, geologic setting, and concept of operations. A set of reference geologic disposal concepts has been developed by the U.S. Department of Energy (DOE) Used Fuel Disposition Campaign, for crystalline rock, clay/shale, bedded salt, and deep borehole (crystalline basement) geologic settings. We performed thermal analysis of these concepts using waste inventory cases representing a range of advanced fuel cycles. Concepts of operation consisting of emplacement mode, repository layout, and engineered barrier descriptions, were selected based on international progress and previous experience in the U.S. repository program. All of the disposal concepts selected for this study use enclosed emplacement modes, whereby waste packages are in direct contact with encapsulating engineered or natural materials. The encapsulating materials (typically clay-based or rock salt) have low intrinsic permeability and plastic rheology that closes voids so that low permeability is maintained. Uniformly low permeability also contributes to chemically reducing conditions common in soft clay, shale, and salt formations. Enclosed modes are associated

  7. Computer aided design and manufacturing of composite propfan blades for a cruise missile wind tunnel model

    NASA Technical Reports Server (NTRS)

    Thorp, Scott A.; Downey, Kevin M.

    1992-01-01

    One of the propulsion concepts being investigated for future cruise missiles is advanced unducted propfans. To support the evaluation of this technology applied to the cruise missile, a joint DOD and NASA test project was conducted to design and then test the characteristics of the propfans on a 0.55-scale, cruise missile model in a NASA wind tunnel. The configuration selected for study is a counterrotating rearward swept propfan. The forward blade row, having six blades, rotates in a counterclockwise direction, and the aft blade row, having six blades, rotates in a clockwise direction, as viewed from aft of the test model. Figures show the overall cruise missile and propfan blade configurations. The objective of this test was to evaluate propfan performance and suitability as a viable propulsion option for next generation of cruise missiles. This paper details the concurrent computer aided design, engineering, and manufacturing of the carbon fiber/epoxy propfan blades as the NASA Lewis Research Center.

  8. Blade Manufacturing Improvement Project: Final Report

    SciTech Connect

    SHERWOOD, KENT

    2002-10-01

    The Blade Manufacturing Improvement Project explores new, unique and improved materials integrated with innovative manufacturing techniques that promise substantial economic enhancements for the fabrication of wind turbine blades. The primary objectives promote the development of advanced wind turbine blade manufacturing in ways that lower blade costs, cut rotor weight, reduce turbine maintenance costs, improve overall turbine quality and increase ongoing production reliability. Foam Matrix (FMI) has developed a wind turbine blade with an engineered foam core, incorporating advanced composite materials and using Resin Transfer Molding (RTM) processes to form a monolithic blade structure incorporating a single molding tool. Patented techniques are employed to increase blade load bearing capability and insure the uniform quality of the manufactured blade. In production quantities, FMI manufacturing innovations may return a sizable per blade cost reduction when compared to the cost of producing comparable blades with conventional methods.

  9. An advanced concept secondary power systems study for an advanced transport technology aircraft

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The application of advanced technology to the design of an integrated secondary power system for future near-sonic long-range transports was investigated. The study showed that the highest payoff is achieved by utilizing secondary power equipment that contributes to minimum cruise drag. This is best accomplished by the use of the dedicated auxiliary power unit concept (inflight APU) as the prime power source for an airplane with a body-mounted engine or by the use of the internal engine generator concept (electrical power extraction from the propulsion engine) for an airplane with a wing-pod-mounted engine.

  10. Successful Surface Treatments for Reducing Instabilities in Advanced Nickel-base Superalloys for Turbine Blades

    NASA Technical Reports Server (NTRS)

    Locci, Ivan E.; MacKay, Rebecca A.; Garg, Anita; Ritzert, Frank J.

    2004-01-01

    An optimized carburization treatment has been developed to mitigate instabilities that form in the microstructures of advanced turbine airfoil materials. Current turbine airfoils consist of a single crystal superalloy base that provides the mechanical performance of the airfoil, a thermal barrier coating (TBC) that reduces the temperature of the base superalloy, and a bondcoat between the superalloy and the TBC, that improves the oxidation and corrosion resistance of the base superalloy and the spallation resistance of the TBC. Advanced nickel-base superalloys containing high levels of refractory metals have been observed to develop an instability called secondary reaction zone (SRZ), which can form beneath diffusion aluminide bondcoats. This instability between the superalloy and the bondcoat has the potential of reducing the mechanical properties of thin-wall turbine airfoils. Controlled gas carburization treatments combined with a prior stress relief heat treatment and adequate surface preparation have been utilized effectively to minimize the formation of SRZ. These additional processing steps are employed before the aluminide bondcoat is deposited and are believed to change the local chemistry and local stresses of the surface of the superalloy. This paper presents the detailed processing steps used to reduce SRZ between platinum aluminide bondcoats and advanced single crystal superalloys.

  11. Advanced Vehicle Concepts and Implications for NextGen

    NASA Technical Reports Server (NTRS)

    Blake, Matt; Smith, Jim; Wright, Ken; Mediavilla Ricky; Kirby, Michelle; Pfaender, Holger; Clarke, John-Paul; Volovoi, Vitali; Dorbian, Christopher; Ashok, Akshay; Reynolds, Tom; Waitz, Ian; Hileman, James; Arunachalam, Sarav; Hedrick, Matt; Vempati, Lakshmi; Laroza, Ryan; denBraven, Wim; Henderson, Jeff

    2010-01-01

    This report presents the results of a major NASA study of advanced vehicle concepts and their implications for the Next Generation Air Transportation System (NextGen). Comprising the efforts of dozens of researchers at multiple institutions, the analyses presented here cover a broad range of topics including business-case development, vehicle design, avionics, procedure design, delay, safety, environmental impacts, and metrics. The study focuses on the following five new vehicle types: Cruise-efficient short takeoff and landing (CESTOL) vehicles Large commercial tiltrotor aircraft (LCTRs) Unmanned aircraft systems (UAS) Very light jets (VLJs) Supersonic transports (SST). The timeframe of the study spans the years 2025-2040, although some analyses are also presented for a 3X scenario that has roughly three times the number of flights as today. Full implementation of NextGen is assumed.

  12. Advanced direct liquefaction concepts for PETC generic units

    SciTech Connect

    Not Available

    1992-04-01

    In the Advance Coal Liquefaction Concept Proposal (ACLCP) carbon monoxide (CO) and water have been proposed as the primary reagents in the pretreatment process. The main objective of this project is to develop a methodology for pretreating coal under mild conditions based on a combination of existing processes which have shown great promise in liquefaction, extraction and pyrolysis studies. The aim of this pretreatment process is to partially depolymerise the coal, eliminate oxygen and diminish the propensity for retograde reactions during subsequent liquefaction. The desirable outcome of the CO pretreatment step should be: (1) enhanced liquefaction activity and/or selectivity toward products of higher quality due to chemical modification of the coal structure; (2) cleaner downstream products; (3) overall improvement in operability and process economics.

  13. Advanced Gas Storage Concepts: Technologies for the Future

    SciTech Connect

    Freeway, Katy; Rogers, R.E.; DeVries, Kerry L.; Nieland, Joel D.; Ratigan, Joe L.; Mellegard, Kirby D.

    2000-02-01

    This full text product includes: 1) A final technical report titled Advanced Underground Gas Storage Concepts, Refrigerated-Mined Cavern Storage and presentations from two technology transfer workshops held in 1998 in Houston, Texas, and Pittsburgh, Pennsylvania (both on the topic of Chilled Gas Storage in Mined Caverns); 2) A final technical report titled Natural Gas Hydrates Storage Project, Final Report 1 October 1997 - 31 May 1999; 3) A final technical report titled Natural Gas Hydrates Storage Project Phase II: Conceptual Design and Economic Study, Final Report 9 June - 10 October 1999; 4) A final technical report titled Commerical Potential of Natural Gas Storage in Lined Rock Caverns (LRC) and presentations from a DOE-sponsored workshop on Alternative Gas Storage Technologies, held Feb 17, 2000 in Pittsburgh, PA; and 5) Phase I and Phase II topical reports titled Feasibility Study for Lowering the Minimum Gas Pressure in Solution-Mined Caverns Based on Geomechanical Analyses of Creep-Induced Damage and Healing.

  14. Advanced composite combustor structural concepts program. Final Report

    SciTech Connect

    Sattar, M.A.; Lohmann, R.P.

    1984-12-01

    An analytical study was conducted to assess the feasibility of and benefits derived from the use of high temperature composite materials in aircraft turbine engine combustor liners. The study included a survey and screening of the properties of three candidate composite materials including tungsten reinforced superalloys, carbon-carbon and silicon carbide (SiC) fibers reinforcing a ceramic matrix of lithium aluminosilicate (LAS). The SiC-LAS material was selected as offering the greatest near term potential primarily on the basis of high temperature capability. A limited experimental investigation was conducted to quantify some of the more critical mechanical properties of the SiC-LAS composite having a multidirection 0/45/-45/90 deg fiber orientation favored for the combustor linear application. Rigorous cyclic thermal tests demonstrated that SiC-LAS was extremely resistant to the thermal fatigue mechanisms that usually limit the life of metallic combustor liners. A thermal design study led to the definition of a composite liner concept that incorporated film cooled SiC-LAS shingles mounted on a Hastelloy X shell. With coolant fluxes consistent with the most advanced metallic liner technology, the calculated hot surface temperatures of the shingles were within the apparent near term capability of the material. Structural analyses indicated that the stresses in the composite panels were low, primarily because of the low coefficient of expansion of the material and it was concluded that the dominant failure mode of the liner would be an as yet unidentified deterioration of the composite from prolonged exposure to high temperature. An economic study, based on a medium thrust size commercial aircraft engine, indicated that the SiC-LAS combustor liner would weigh 22.8N (11.27 lb) less and cost less to manufacture than advanced metallic liner concepts intended for use in the late 1980's.

  15. Evaluation of wind tunnel performance testings of an advanced 45 deg swept 8-bladed propeller at Mach numbers from 0.45 to 0.85

    NASA Technical Reports Server (NTRS)

    Rohrbach, C.; Metzger, F. B.; Black, D. M.; Ladden, R. M.

    1982-01-01

    The increased emphasis of fuel conservation in the world and the rapid increase in the cost of jet fuel has stimulated a series of studies of both conventional and unconventional propulsion systems for commercial aircraft. The results of these studies indicate that a fuel saving of 15 to 30 percent may be realized by the use of an advanced high-speed turboprop (Prop-Fan) compared to aircraft equipped with high bypass turbofan engines of equivalent technology. The Prop-Fan propulsion system is being investigated as part of the NASA Aircraft Energy Efficient Program. This effort includes the wind tunnel testing of a series of 8 and 10-blade Prop-Fan models incorporate swept blades. Test results indicate efficiency levels near the goal of 80 percent at Mach 0.8 cruise and an altitude of 10.67 km (35,000 ft). Each successive swept model has shown improved efficiency relative to the straight blade model. The fourth model, with 45 deg swept blades reported herein, shows a net efficiency of 78.2 at the design point with a power loading of 301 kW/sq meter and a tip speed of 243.8 m/sec (800 ft/sec.).

  16. Aeronautical technology 2000: A projection of advanced vehicle concepts

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The Aeronautics and Space Engineering Board (ASEB) of the National Research Council conducted a Workshop on Aeronautical Technology: a Projection to the Year 2000 (Aerotech 2000 Workshop). The panels were asked to project advances in aeronautical technologies that could be available by the year 2000. As the workshop was drawing to a close, it became evident that a more comprehensive investigation of advanced air vehicle concepts than was possible in the limited time available at the workshop would be valuable. Thus, a special panel on vehicle applications was organized. In the course of two meetings, the panel identified and described representative types of aircraft judged possible with the workshop's technology projections. These representative aircraft types include: military aircraft; transport aircraft; rotorcraft; extremely high altitude aircraft; and transatmospheric aircraft. Improvements in performance, efficiency, and operational characteristics possible through the application of the workshop's year 2000 technology projections were discussed. The subgroups also identified the technologies considered essential and enhancing or supporting to achieve the projected aircraft improvements.

  17. Advanced Short Takeoff and Vertical Landing (ASTOVL) Concepts Tested

    NASA Technical Reports Server (NTRS)

    1995-01-01

    In this cooperative program between NASA, Lockheed Corporation, and the Advanced Research and Projects Agency (ARPA), an advanced short takeoff and vertical landing (ASTOVL) model was tested in the 9- by 15-Foot Low-Speed Wind Tunnel at the NASA Lewis Research Center. The 10-percent scaled model was tested over a range of headwind velocities from 25 to 120 kn. This inlet/forebody test was a key part of an important Department of Defense program investigation enabling technologies for future high-performance ASTOVL aircraft. The Lockheed concept is focused on a shaft-coupled lift fan system centered around Pratt & Whitney's F119 power plant. As envisioned, a conventional takeoff and landing version (CTOL) would replace the U.S. Air Force's F-16's. The ASTOVL version would eventually replace Marine and, possibly, British Harrier aircraft. The ASTOVL and CTOL versions are scheduled to begin their manufacturing development phases in 2000. The purpose of this test was to acquire data pertinent to the inlet-forebody model. The test was very successful. Both steady-state and dynamic data were obtained. This small-scale testing, which is directed at reducing risks, may greatly reduce the risks on a full-scale aircraft.

  18. Advanced Concept Exploration for Fast Ignition Science Program, Final Report

    SciTech Connect

    Stephens, Richard Burnite; McLean, Harry M.; Theobald, Wolfgang; Akli, Kramer U.; Beg, Farhat N.; Sentoku, Yasuhiko; Schumacher, Douglass W.; Wei, Mingsheng

    2013-09-04

    The Fast Ignition (FI) Concept for Inertial Confinement Fusion (ICF) has the potential to provide a significant advance in the technical attractiveness of Inertial Fusion Energy reactors. FI differs from conventional “central hot spot” (CHS) target ignition by decoupling compression from heating: using a laser (or heavy ion beam or Z pinch) drive pulse (10’s of nanoseconds) to create a dense fuel and a second, much shorter (~10 picoseconds) high intensity pulse to ignite a small volume within the dense fuel. The physics of fast ignition process was the focus of our Advanced Concept Exploration (ACE) program. Ignition depends critically on two major issues involving Relativistic High Energy Density (RHED) physics: The laser-induced creation of fast electrons and their propagation in high-density plasmas. Our program has developed new experimental platforms, diagnostic packages, computer modeling analyses, and taken advantage of the increasing energy available at laser facilities to advance understanding of the fundamental physics underlying these issues. Our program had three thrust areas: • Understand the production and characteristics of fast electrons resulting from FI relevant laser-plasma interactions and their dependence on laser prepulse and laser pulse length. • Investigate the subsequent fast electron transport in solid and through hot (FI-relevant) plasmas. • Conduct and understand integrated core-heating experiments by comparison to simulations. Over the whole period of this project (three years for this contract), we have greatly advanced our fundamental understanding of the underlying properties in all three areas: • Comprehensive studies on fast electron source characteristics have shown that they are controlled by the laser intensity distribution and the topology and plasma density gradient. Laser pre-pulse induced pre-plasma in front of a solid surface results in increased stand-off distances from the electron origin to the high density

  19. Advanced concepts in ground thermal energy storage systems

    NASA Astrophysics Data System (ADS)

    Woods, Kevin David

    In recent years, ground thermal energy storage has become a topic of interest in the energy community for solar thermal energy storage systems, ground sourced heat pump systems, and data center thermal management systems due to an increase in the energy efficiency of such systems utilizing the ground as a thermal reservoir. The most common method for transferring thermal energy to the ground formation is the geothermal borehole. This dissertation presents the state of the art in geothermal borehole modeling and derives novel analytical functions to model advanced concepts concerning their operation. The novel solutions derived allow a geothermal borehole designer to better understand and design ground energy storage systems. The state of the art in geothermal borehole modeling is the stationary line source solution which is limited to boreholes operating without groundwater flow. Novel solutions for modeling a geothermal borehole with groundwater advection are presented through derivation of a transient moving line source solution as well as a transient moving cylindrical surface source solution. These solutions are applied to model a specific type of open loop geothermal borehole called a standing column well with groundwater advection and are compared to empirical and numerical data for validation. The dissertation then moves into derivation of a property determination method for geothermal boreholes with groundwater advection. The traditional property determination method used to obtain ground formation properties is based on the stationary transient line source method and fails in the presence of groundwater flow. The proposed novel property determination method calculates the thermal conductivity, thermal diffusivity, and superficial flow velocity of groundwater within a ground formation. These methods and solutions are novel tools allowing for geothermal borehole designers to grasp a better understanding of the systems they are designing as well as open other

  20. Advanced turboprop aircraft flyover noise: Annoyance to counter-rotating-propeller configurations with a different number of blades on each rotor: Preliminary results

    NASA Technical Reports Server (NTRS)

    Mccurdy, David A.

    1988-01-01

    A laboratory experiment was conducted to quantify the annoyance of people to the flyover noise of advanced turboprop aircraft with counter-rotating propellers (CRP) having a different number of blades on each rotor (nxm, e.g., 10 x 8, 12 x 11). The objectives were: (1) compare annoyance to nxm CRP advanced turboprop aircraft with annoyance to conventional turboprop and jet aircraft; (2) determine the effects of tonal content on annoyance; and (3) determine the ability of aircraft noise measurement procedures and corrections to predict annoyance for this new class of aircraft. A computer synthesis system was used to generate 35 realistic, time-varying simulations of advanced turboprop takeoff noise in which the tonal content was systematically varied to represent combinations of 15 fundamental frequency (blade passage frequency) combinations and three tone-to-broadband noise ratios. The fundamental frequencies, which represented blade number combinations from 6 x 5 to 13 x 12 and 7 x 5 to 13 x 11, ranged from 112.5 to 292.5 Hz. The three tone-to-broadband noise ratios were 0, 15, and 30 dB. These advanced turboprop simulations along with recordings of five conventional turboprop takeoffs and five conventional jet takeoffs were presented at D-weighted sound pressure levels of 70, 80, and 90 dB to 64 subjects in an anechoic chamber. Analyses of the subjects' annoyance judgments compare the three categories of aircraft and examine the effects of the differences in tonal content among the advanced turboprop noises. The annoyance prediction ability of various noise measurement procedures and corrections is also examined.

  1. Theoretical Investigations of Plasma-Based Accelerators and Other Advanced Accelerator Concepts

    SciTech Connect

    Shuets, G.

    2004-05-21

    Theoretical investigations of plasma-based accelerators and other advanced accelerator concepts. The focus of the work was on the development of plasma based and structure based accelerating concepts, including laser-plasma, plasma channel, and microwave driven plasma accelerators.

  2. Advanced fusion MHD power conversion using the CFAR (compact fusion advanced Rankine) cycle concept

    SciTech Connect

    Hoffman, M.A.; Campbell, R.; Logan, B.G.; Lawrence Livermore National Lab., CA )

    1988-10-01

    The CFAR (compact fusion advanced Rankine) cycle concept for a tokamak reactor involves the use of a high-temperature Rankine cycle in combination with microwave superheaters and nonequilibrium MHD disk generators to obtain a compact, low-capital-cost power conversion system which fits almost entirely within the reactor vault. The significant savings in the balance-of-plant costs are expected to result in much lower costs of electricity than previous concepts. This paper describes the unique features of the CFAR cycle and a high- temperature blanket designed to take advantage of it as well as the predicted performance of the MHD disk generators using mercury seeded with cesium. 40 refs., 8 figs., 3 tabs.

  3. Proof-of-Concept for an Advanced Sunphotometer

    NASA Astrophysics Data System (ADS)

    Brill, R.; Strawa, A. W.; Papdopoulos, P.; Le, T.

    2007-12-01

    Aerosols have a profound effect on the radiation balance of the atmosphere. Current estimates of the direct and indirect effects are -0.9 to -0.1 and -1.8 to -0.3 W m-2, respectively, but remain highly uncertain (IPCC, 2007). These uncertainties are tied to our inability to accurately estimate spatial and temporal distributions of aerosol concentrations, size, and composition. Measurements of aerosol optical depth (AOD) are needed from widely distributed locations, both over land and ocean. AOD measurements from the surface are routinely made by sunphotometers. Most notably, NASA's AERONET system makes routine measurements of AOD at many sites throughout the globe. The problem is that very few measurements are made over the ocean because of operational considerations, i.e. ships do not present a stable platform and the salt water spray is damaging to the mechanisms used by the sunphotometers to track the sun. This paper reports on the development of a sunphotometer that can obtain AOD without moving parts. Such an instrument has the potential to be small, lightweight, and rugged. Potential applications are use in extreme environments, on ships and ocean buoys, and perhaps in unmanned aerial systems (UAS). Due to its small size and light weight, the Advanced Sun Photometer can be adapted for use on extraterrestrial bodies with sensible atmospheres, such as Mars or Titan. Concept: Eliminating the need for a tracking mechanism can significantly reduce instrument weight and size while increasing system robustness. The Advanced Sunphotometer uses a compact optical system to provide a hemispherical field of view, removing the need for a sun tracking mechanism. A CCD array is placed at the base of the optical system captures and records the light. Measurements at specific wavelengths are achieved by interposing various interference filters into the light path by means of a filter wheel. The instrument measures the diffuse radiation as well as the direct sun beam. Computer

  4. Fiber-Reinforced-Foam (FRF) Core Composite Sandwich Panel Concept for Advanced Composites Technologi

    NASA Technical Reports Server (NTRS)

    2010-01-01

    Fiber-Reinforced-Foam (FRF) Core Composite Sandwich Panel Concept for Advanced Composites Technologies Project - Preliminary Manufacturing Demonstration Articles for Ares V Payload Shroud Barrel Acreage Structure

  5. Advanced transportation system studies. Alternate propulsion subsystem concepts: Propulsion database

    NASA Technical Reports Server (NTRS)

    Levack, Daniel

    1993-01-01

    The Advanced Transportation System Studies alternate propulsion subsystem concepts propulsion database interim report is presented. The objective of the database development task is to produce a propulsion database which is easy to use and modify while also being comprehensive in the level of detail available. The database is to be available on the Macintosh computer system. The task is to extend across all three years of the contract. Consequently, a significant fraction of the effort in this first year of the task was devoted to the development of the database structure to ensure a robust base for the following years' efforts. Nonetheless, significant point design propulsion system descriptions and parametric models were also produced. Each of the two propulsion databases, parametric propulsion database and propulsion system database, are described. The descriptions include a user's guide to each code, write-ups for models used, and sample output. The parametric database has models for LOX/H2 and LOX/RP liquid engines, solid rocket boosters using three different propellants, a hybrid rocket booster, and a NERVA derived nuclear thermal rocket engine.

  6. Advanced energy conversion concept for beamed-energy propulsion

    NASA Astrophysics Data System (ADS)

    Myrabo, Leik N.

    1987-08-01

    Basic research was performed on an innovative power conversion concept for trans atmospheric, beamed energy propulsion: a new class of External Surface Impulse (ESI) thrusters. This advanced thruster principle could be used for atmospheric VTOL, high acceleration, and lateral flight (e.g., short-term cruise) propulsion of Single-Stage-To-Orbit (SSTO) beam-powered shuttlecraft of the next century. Three classes of ESI thrusters were initially examined: (1) simple thermal, (2) electrostatic, and (3) electromagnetic. Beam power wavelengths from 10 cm (microwave) to 0.3 micron (laser) were considered. The subsequent effort concentrated on the simple thermal repetitively-pulsed ESI thrusters, energized with laser power and using air as the working fluid. Laser frequencies were selected because of the relative wealth of experimental data and theoretical research on laser impulse coupling existing in the literature. The first year analytical effort has proven conclusively that such an engine can deliver high levels of thrust-to-beam-power at liftoff (e.g., at least an order of magnitude greater than beam-powered hydrogen-fueled rockets), with infinite specific impulse (decreased only, perhaps, by ablation of the thruster surface). Later along an orbital trajectory, the primary propulsion function would transition to other modes; upon leaving the atmosphere, the SSTO vehicle would continue in a pure rocket mode.

  7. Advanced transportation system studies. Alternate propulsion subsystem concepts: Propulsion database

    NASA Astrophysics Data System (ADS)

    Levack, Daniel

    1993-04-01

    The Advanced Transportation System Studies alternate propulsion subsystem concepts propulsion database interim report is presented. The objective of the database development task is to produce a propulsion database which is easy to use and modify while also being comprehensive in the level of detail available. The database is to be available on the Macintosh computer system. The task is to extend across all three years of the contract. Consequently, a significant fraction of the effort in this first year of the task was devoted to the development of the database structure to ensure a robust base for the following years' efforts. Nonetheless, significant point design propulsion system descriptions and parametric models were also produced. Each of the two propulsion databases, parametric propulsion database and propulsion system database, are described. The descriptions include a user's guide to each code, write-ups for models used, and sample output. The parametric database has models for LOX/H2 and LOX/RP liquid engines, solid rocket boosters using three different propellants, a hybrid rocket booster, and a NERVA derived nuclear thermal rocket engine.

  8. Investigations and advanced concepts on gyrotron interaction modeling and simulations

    SciTech Connect

    Avramidis, K. A.

    2015-12-15

    In gyrotron theory, the interaction between the electron beam and the high frequency electromagnetic field is commonly modeled using the slow variables approach. The slow variables are quantities that vary slowly in time in comparison to the electron cyclotron frequency. They represent the electron momentum and the high frequency field of the resonant TE modes in the gyrotron cavity. For their definition, some reference frequencies need to be introduced. These include the so-called averaging frequency, used to define the slow variable corresponding to the electron momentum, and the carrier frequencies, used to define the slow variables corresponding to the field envelopes of the modes. From the mathematical point of view, the choice of the reference frequencies is, to some extent, arbitrary. However, from the numerical point of view, there are arguments that point toward specific choices, in the sense that these choices are advantageous in terms of simulation speed and accuracy. In this paper, the typical monochromatic gyrotron operation is considered, and the numerical integration of the interaction equations is performed by the trajectory approach, since it is the fastest, and therefore it is the one that is most commonly used. The influence of the choice of the reference frequencies on the interaction simulations is studied using theoretical arguments, as well as numerical simulations. From these investigations, appropriate choices for the values of the reference frequencies are identified. In addition, novel, advanced concepts for the definitions of these frequencies are addressed, and their benefits are demonstrated numerically.

  9. Advanced 3D imaging lidar concepts for long range sensing

    NASA Astrophysics Data System (ADS)

    Gordon, K. J.; Hiskett, P. A.; Lamb, R. A.

    2014-06-01

    Recent developments in 3D imaging lidar are presented. Long range 3D imaging using photon counting is now a possibility, offering a low-cost approach to integrated remote sensing with step changing advantages in size, weight and power compared to conventional analogue active imaging technology. We report results using a Geiger-mode array for time-of-flight, single photon counting lidar for depth profiling and determination of the shape and size of tree canopies and distributed surface reflections at a range of 9km, with 4μJ pulses with a frame rate of 100kHz using a low-cost fibre laser operating at a wavelength of λ=1.5 μm. The range resolution is less than 4cm providing very high depth resolution for target identification. This specification opens up several additional functionalities for advanced lidar, for example: absolute rangefinding and depth profiling for long range identification, optical communications, turbulence sensing and time-of-flight spectroscopy. Future concepts for 3D time-of-flight polarimetric and multispectral imaging lidar, with optical communications in a single integrated system are also proposed.

  10. A review of accelerator concepts for the Advanced Hydrotest Facility

    SciTech Connect

    Toepfer, A.J.

    1998-08-01

    The Advanced Hydrotest Facility (AHF) is a facility under consideration by the Department of Energy (DOE) for conducting explosively-driven hydrodynamic experiments. The major diagnostic tool at AHF will be a radiography accelerator having radiation output capable of penetrating very dense dynamic objects on multiple viewing axes with multiple pulses on each axis, each pulse having a time resolution capable of freezing object motion ({approx}50-ns) and achieving a spatial resolution {approx}1 mm at the object. Three accelerator technologies are being considered for AHF by the DOE national laboratories at Los Alamos (LANL), Livermore (LLNL), and Sandia (SNL). Two of these are electron accelerators that will produce intense x-ray pulses from a converter target yielding a dose {approx}1,000--2,000 Rads {at} 1 meter. LLNL has proposed a 16--20 MeV, 3--6 kA linear induction accelerator (LIA) driven by FET-switched modulators driving metglas loaded cavities. SNL has proposed a 12-MeV, 40-kA Inductive Voltage Adder (IVA) accelerator based on HERMES III pulsed power technology. The third option is a 25--50-GeV proton accelerator capable of {approx}10{sup 13} protons/pulse proposed by LANL. This paper will review the current status of the three accelerator concepts for AHF.

  11. Investigations and advanced concepts on gyrotron interaction modeling and simulations

    NASA Astrophysics Data System (ADS)

    Avramidis, K. A.

    2015-12-01

    In gyrotron theory, the interaction between the electron beam and the high frequency electromagnetic field is commonly modeled using the slow variables approach. The slow variables are quantities that vary slowly in time in comparison to the electron cyclotron frequency. They represent the electron momentum and the high frequency field of the resonant TE modes in the gyrotron cavity. For their definition, some reference frequencies need to be introduced. These include the so-called averaging frequency, used to define the slow variable corresponding to the electron momentum, and the carrier frequencies, used to define the slow variables corresponding to the field envelopes of the modes. From the mathematical point of view, the choice of the reference frequencies is, to some extent, arbitrary. However, from the numerical point of view, there are arguments that point toward specific choices, in the sense that these choices are advantageous in terms of simulation speed and accuracy. In this paper, the typical monochromatic gyrotron operation is considered, and the numerical integration of the interaction equations is performed by the trajectory approach, since it is the fastest, and therefore it is the one that is most commonly used. The influence of the choice of the reference frequencies on the interaction simulations is studied using theoretical arguments, as well as numerical simulations. From these investigations, appropriate choices for the values of the reference frequencies are identified. In addition, novel, advanced concepts for the definitions of these frequencies are addressed, and their benefits are demonstrated numerically.

  12. NASA Advanced Explorations Systems: Concepts for Logistics to Living

    NASA Technical Reports Server (NTRS)

    Shull, Sarah A.; Howe, A. Scott; Flynn, Michael T.; Howard, Robert

    2012-01-01

    , Howard 2010]. Several of the L2L concepts that have shown the most potential in the past are based on NASA cargo transfer bags (CTBs) or their equivalents which are currently used to transfer cargo to and from the ISS. A high percentage of all logistics supplies are packaging mass and for a 6-month mission a crew of four might need over 100 CTBs. These CTBs are used for on-orbit transfer and storage but eventually becomes waste after use since down mass is very limited. The work being done in L2L also considering innovative interior habitat construction that integrate the CTBs into the walls of future habitats. The direct integration could provide multiple functions: launch packaging, stowage, radiation protection, water processing, life support augmentation, as well as structure. Reuse of these CTBs would reduce the amount of waste generated and also significantly reduce future up mass requirements for exploration missions. Also discussed here is the L2L water wall , an innovative reuse of an unfolded CTB as a passive water treatment system utilizing forward osmosis. The bags have been modified to have an inner membrane liner that allows them to purify wastewater. They may also provide a structural water-wall element that can be used to provide radiation protection and as a structural divider. Integration of the components into vehicle/habitat architecture and consideration of operations concepts and human factors will be discussed. In the future these bags could be designed to treat wastewater, concentrated brines, and solid wastes, and to dewater solid wastes and produce a bio-stabilized construction element. This paper will describe the follow-on work done in design, fabrication and demonstrations of various L2L concepts, including advanced CTBs for reuse/repurposing, internal outfitting studies and the CTB-based forward osmosis water wall.

  13. WindPACT Turbine Design Scaling Studies Technical Area 1-Composite Blades for 80- to 120-Meter Rotor

    SciTech Connect

    Griffin, D.A.

    2001-04-30

    The United States Department of Energy (DOE) through the National Renewable Energy Laboratory (NREL) implemented the Wind Partnership for Advanced Component Technologies (WindPACT) program. As part of the WindPACT program, Global Energy Concepts, LLC (GEC), was awarded contract number YAM-0-30203-01 to examine Technical Area 1-Blade Scaling, Technical Area 2-Turbine Rotor and Blade Logistics, and Technical Area 3-Self-Erecting Towers. This report documents the results of GEC's Technical Area 1-Blade Scaling. The primary objectives of the Blade-Scaling Study are to assess the scaling of current materials and manufacturing technologies for blades of 40 to 60 meters in length, and to develop scaling curves of estimated cost and mass for rotor blades in that size range.

  14. Superhybrid composite blade impact studies

    NASA Technical Reports Server (NTRS)

    Chamis, C. C.; Lark, R. F.; Sinclair, J. H.

    1980-01-01

    The feasibility of superhybrid composite blades for meeting the mechanical design and impact resistance requirements of large fan blades for aircraft turbine engine applications was investigated. Two design concepts were evaluated: leading edge spar (TiCom) and center spar (TiCore), both with superhybrid composite shells. The investigation was both analytical and experimental. The results obtained show promise that superhybrid composites can be used to make light weight, high quality, large fan blades with good structural integrity. The blades tested successfully demonstrated their ability to meet steady state operating conditions, overspeed, and small bird impact requirements.

  15. Superhybrid composite blade impact studies

    NASA Technical Reports Server (NTRS)

    Chamis, C. C.; Lark, R. F.; Sinclair, J. H.

    1981-01-01

    An investigation was conducted to determine the feasibility of superhybrid composite blades for meeting the mechanical design and impact resistance requirements of large fan blades for aircraft turbine engine applications. Two design concepts were evaluated: (1) leading edge spar (TiCom) and (2) center spar (TiCore), both with superhybrid composite shells. The investigation was both analytical and experimental. The results obtained show promise that superhybrid composites can be used to make light-weight, high-quality, large fan blades with good structural integrity. The blades tested successfully demonstrated their ability to meet steady-state operating conditions, overspeed, and small bird impact requirements.

  16. Advancing-side directivity and retreating-side interactions of model rotor blade-vortex interaction noise

    NASA Technical Reports Server (NTRS)

    Martin, R. M.; Splettstoesser, W. R.; Elliott, J. W.; Schultz, K.-J.

    1988-01-01

    Acoustic data are presented from a 40 percent scale model of the four-bladed BO-105 helicopter main rotor, tested in a large aerodynamic wind tunnel. Rotor blade-vortex interaction (BVI) noise data in the low-speed flight range were acquired using a traversing in-flow microphone array. Acoustic results presented are used to assess the acoustic far field of BVI noise, to map the directivity and temporal characteristics of BVI impulsive noise, and to show the existence of retreating-side BVI signals. The characterics of the acoustic radiation patterns, which can often be strongly focused, are found to be very dependent on rotor operating condition. The acoustic signals exhibit multiple blade-vortex interactions per blade with broad impulsive content at lower speeds, while at higher speeds, they exhibit fewer interactions per blade, with much sharper, higher amplitude acoustic signals. Moderate-amplitude BVI acoustic signals measured under the aft retreating quadrant of the rotor are shown to originate from the retreating side of the rotor.

  17. Comparison of model helicopter rotor primary and secondary blade/vortex interaction blade slap

    NASA Astrophysics Data System (ADS)

    Hubbard, J. E., Jr.; Leighton, K. P.

    1984-05-01

    A study of the relative importance of blade/vortex interactions which occur on the retreating side of a model helicopter rotor disk is described. Some of the salient characteristics of this phenomenon are presented and discussed. It is shown that the resulting Secondary blade slap may be of equal or greater intensity than the advancing side (Primary) blade slap. Instrumented model helicopter rotor data is presented which reveals the nature of the retreating blade/vortex interaction. The importance of Secondary blade slap as it applies to predictive techniques or approaches is discussed. When Secondary blade slap occurs it acts to enlarge the window of operating conditions for which blade slap exists.

  18. A comparison of model helicopter rotor Primary and Secondary blade/vortex interaction blade slap

    NASA Technical Reports Server (NTRS)

    Hubbard, J. E., Jr.; Leighton, K. P.

    1983-01-01

    A study of the relative importance of blade/vortex interactions which occur on the retreating side of a model helicopter rotor disk is described. Some of the salient characteristics of this phenomenon are presented and discussed. It is shown that the resulting Secondary blade slap may be of equal or greater intensity than the advancing side (Primary) blade slap. Instrumented model helicopter rotor data is presented which reveals the nature of the retreating blade/vortex interaction. The importance of Secondary blade slap as it applies to predictive techniques or approaches is discussed. When Secondary blade slap occurs it acts to enlarge the window of operating conditions for which blade slap exists.

  19. Blade System Design Studies Volume I: Composite Technologies for Large Wind Turbine Blades

    SciTech Connect

    GRIFFIN, DAYTON A.; ASHWILL, THOMAS D.

    2002-07-01

    As part of the U.S. Department of Energy's Wind Partnerships for Advanced Component Technologies (WindPACT) program, Global Energy Concepts LLC (GEC) is performing a study concerning innovations in materials, processes and structural configurations for application to wind turbine blades in the multi-megawatt range. The project team for this work includes experts in all areas of wind turbine blade design, analysis, manufacture, and testing. Constraints to cost-effective scaling-up of the current commercial blade designs and manufacturing methods are identified, including self-gravity loads, transportation, and environmental considerations. A trade-off study is performed to evaluate the incremental changes in blade cost, weight, and stiffness for a wide range of composite materials, fabric types, and manufacturing processes. Fiberglass/carbon fiber hybrid blades are identified as having a promising combination of cost, weight, stiffness and fatigue resistance. Vacuum-assisted resin transfer molding, resin film infision, and pre-impregnated materials are identified as having benefits in reduced volatile emissions, higher fiber content, and improved laminate quality relative to the baseline wet lay-up process. Alternative structural designs are identified, including jointed configurations to facilitate transportation. Based on the results to date, recommendations are made for further evaluation and testing under this study to verify the predicted material and structural performance.

  20. Fiber composite fan blade impact improvement program

    NASA Technical Reports Server (NTRS)

    Oller, T. L.

    1976-01-01

    The results of a 20-month program, designed to investigate parameters which effect the foreign object damage resulting from ingestion of birds into fan blades are described. Work performed on this program included the design, fabrication, and impact testing of QCSEE fan blades to demonstrate improvement in resistance relative to existing blades and also the design and demonstration of a pin root attachment concept.

  1. Fiberglass Composite Blades for the 4 MW - WTS-4 Wind Turbine

    NASA Technical Reports Server (NTRS)

    Bussolari, R. J.

    1982-01-01

    The design and fabrication of composite blades for the WTS-4, a four-megawatt horizontal-axis wind turbine, is discussed. The blade consists of a two-cell, monolithic structure of filament-wound, fiberglass/epoxy composite. Filament winding is a low-cost process which can produce a blade with an aerodynamically efficient airfoil and planform with nonlinear twist to achieve high performance in terms of energy capture. Its retention provides a redundant attachment for long, durable life and safety. Advanced tooling concepts and as sophisticated computer control is used to achieve the unique filament-wound shape.

  2. Relevance of aerodynamic modelling for load reduction control strategies of two-bladed wind turbines

    NASA Astrophysics Data System (ADS)

    Luhmann, B.; Cheng, P. W.

    2014-06-01

    A new load reduction concept is being developed for the two-bladed prototype of the Skywind 3.5MW wind turbine. Due to transport and installation advantages both offshore and in complex terrain two-bladed turbine designs are potentially more cost-effective than comparable three-bladed configurations. A disadvantage of two-bladed wind turbines is the increased fatigue loading, which is a result of asymmetrically distributed rotor forces. The innovative load reduction concept of the Skywind prototype consists of a combination of cyclic pitch control and tumbling rotor kinematics to mitigate periodic structural loading. Aerodynamic design tools must be able to model correctly the advanced dynamics of the rotor. In this paper the impact of the aerodynamic modelling approach is investigated for critical operational modes of a two-bladed wind turbine. Using a lifting line free wake vortex code (FVM) the physical limitations of the classical blade element momentum theory (BEM) can be evaluated. During regular operation vertical shear and yawed inflow are the main contributors to periodic blade load asymmetry. It is shown that the near wake interaction of the blades under such conditions is not fully captured by the correction models of BEM approach. The differing prediction of local induction causes a high fatigue load uncertainty especially for two-bladed turbines. The implementation of both cyclic pitch control and a tumbling rotor can mitigate the fatigue loading by increasing the aerodynamic and structural damping. The influence of the time and space variant vorticity distribution in the near wake is evaluated in detail for different cyclic pitch control functions and tumble dynamics respectively. It is demonstrated that dynamic inflow as well as wake blade interaction have a significant impact on the calculated blade forces and need to be accounted for by the aerodynamic modelling approach. Aeroelastic simulations are carried out using the high fidelity multi body

  3. Advanced-power-reactor design concepts and performance characteristics

    NASA Technical Reports Server (NTRS)

    Davison, H. W.; Kirchgessner, T. A.; Springborn, R. H.; Yacobucci, H. G.

    1974-01-01

    Five reactor cooling concepts which allow continued reactor operation following a single rupture of the coolant system are presented for application with the APR. These concepts incorporate convective cooling, double containment, or heat pipes to ensure operation after a coolant line rupture. Based on an evaluation of several control system concepts, a molybdenum clad, beryllium oxide sliding reflector located outside the pressure vessel is recommended.

  4. Razor Blades to Computers.

    ERIC Educational Resources Information Center

    Schneider, Arthur

    Stages in developing editing equipment and processes for videotape are described. In 1956, when the first broadcast videotape recorders were installed, a splicing block, consisting of an aluminum block, steel ruler, and sharp razor blade, was used. Gradually, technicians developed more sophisticated methods. At present, two very advanced methods…

  5. Advanced Offshore Wind Turbine/Foundation Concept for the Great Lakes

    SciTech Connect

    Afjeh, Abdollah A.; Windpower, Nautica; Marrone, Joseph; Wagner, Thomas

    2013-08-29

    This project investigated a conceptual 2-bladed rotor wind turbine design and assessed its feasibility for installation in the Great Lakes. The levelized cost of energy was used for this purpose. A location in Lake Erie near the coast of Cleveland, Ohio was selected as the application site. The loading environment was defined using wind and wave data collected at a weather station in Lake Erie near Cleveland. In addition, the probability distributions of the annual significant wave height and wind speed were determined. A model of the dependence of the above two quantities was also developed and used in the study of wind turbine system loads. Loads from ice floes and ridges were also included.The NREL 5 MW 3-bladed rotor wind turbine concept was used as the baseline design. The proposed turbine design employs variable pitch blade control with tip-brakes and a teeter mechanism. The rotor diameter, rated power and the tower dimensions were selected to closely match those of the NREL 5 MW wind turbine.A semi-floating gravity base foundation was designed for this project primarily to adapt to regional logistical constraints to transport and install the gravity base foundation. This foundation consists of, from bottom to top, a base plate, a buoyancy chamber, a taper zone, a column (with ice cone), and a service platform. A compound upward-downward ice cone was selected to secure the foundation from moving because of ice impact.The turbine loads analysis was based on International ElectroTechnical Committee (IEC) Standard 61400-1, Class III winds. The NREL software FAST was the primary computational tool used in this study to determine all design load cases. An initial set of studies of the dynamics of wind turbines using Automatic Dynamic Analysis of Mechanical Systems (ADAMS) demonstrated that FAST and ADAMS load predictions were comparable. Because of its relative simplicity and short run times, FAST was selected for this study. For ice load calculations, a method

  6. NASA's Advanced Information Systems Technology (AIST) Program: Advanced Concepts and Disruptive Technologies

    NASA Astrophysics Data System (ADS)

    Little, M. M.; Moe, K.; Komar, G.

    2014-12-01

    NASA's Earth Science Technology Office (ESTO) manages a wide range of information technology projects under the Advanced Information Systems Technology (AIST) Program. The AIST Program aims to support all phases of NASA's Earth Science program with the goal of enabling new observations and information products, increasing the accessibility and use of Earth observations, and reducing the risk and cost of satellite and ground based information systems. Recent initiatives feature computational technologies to improve information extracted from data streams or model outputs and researchers' tools for Big Data analytics. Data-centric technologies enable research communities to facilitate collaboration and increase the speed with which results are produced and published. In the future NASA anticipates more small satellites (e.g., CubeSats), mobile drones and ground-based in-situ sensors will advance the state-of-the-art regarding how scientific observations are performed, given the flexibility, cost and deployment advantages of new operations technologies. This paper reviews the success of the program and the lessons learned. Infusion of these technologies is challenging and the paper discusses the obstacles and strategies to adoption by the earth science research and application efforts. It also describes alternative perspectives for the future program direction and for realizing the value in the steps to transform observations from sensors to data, to information, and to knowledge, namely: sensor measurement concepts development; data acquisition and management; data product generation; and data exploitation for science and applications.

  7. Advanced and innovative wind energy energy concept development: dynamic inducer system. Research report

    SciTech Connect

    Lissaman, P.B.S.; Zalay, A.D.; Hibbs, B.H.

    1981-05-01

    The performance benefits of the dynamic inducer tip vane system have been experimentally demonstrated for the first time. Tow-tests conducted on a three-bladed, 3.6-meter diameter rotor have shown that a dynamic inducer can achieve a power coefficient (based upon power blade swept area) of 0.5, which exceeds that of a plain rotor by about 35%. Wind tunnel tests conducted on a one-third scale model of the dynamic inducer achieved a power coefficient of 0.62 which exceeded that of a plain rotor by about 70%. The dynamic inducer substantially improves the performance of conventional rotors and indications are that higher power coefficients can be achieved through additional aerodynamic optimization. It is noted that the wind turbine system used as a baseline unit is the Kedco 1200, a conventional propeller-type wind turbine with power blades designed for optimum performance without tip vane augmentation. In addition, the tip vane utilized a standard conventional NACA airfoil selected on conservative grounds to guarantee acceptable performance. More advanced high life-to-drag airfoil sections are expected to improve the tip vane effectiveness.

  8. Lacking a Formal Concept of Limit: Advanced Non-Mathematics Students' Personal Concept Definitions

    ERIC Educational Resources Information Center

    Beynon, Kenneth A.; Zollman, Alan

    2015-01-01

    This mixed-methods study examines the conceptual understanding of limit among 22 undergraduate engineering students from two different sections of the same introductory differential equations course. The participants' concepts of limit (concept images and personal concept definitions) were examined using written tasks followed by one-on-one…

  9. Advanced composites structural concepts and materials technologies for primary aircraft structures: Design/manufacturing concept assessment

    NASA Technical Reports Server (NTRS)

    Chu, Robert L.; Bayha, Tom D.; Davis, HU; Ingram, J. ED; Shukla, Jay G.

    1992-01-01

    Composite Wing and Fuselage Structural Design/Manufacturing Concepts have been developed and evaluated. Trade studies were performed to determine how well the concepts satisfy the program goals of 25 percent cost savings, 40 percent weight savings with aircraft resizing, and 50 percent part count reduction as compared to the aluminum Lockheed L-1011 baseline. The concepts developed using emerging technologies such as large scale resin transfer molding (RTM), automatic tow placed (ATP), braiding, out-of-autoclave and automated manufacturing processes for both thermoset and thermoplastic materials were evaluated for possible application in the design concepts. Trade studies were used to determine which concepts carry into the detailed design development subtask.

  10. Advanced design concepts in nuclear electric propulsion. [and spacecraft configurations

    NASA Technical Reports Server (NTRS)

    Peelgren, M. L.; Mondt, J. F.

    1974-01-01

    Conceptual designs of the nuclear propulsion programs are reported. Major areas of investigation were (1) design efforts on spacecraft configuration and heat rejection subsystem, (2) high-voltage thermionic reactor concepts, and (3) dual-mode spacecraft configuration study.

  11. Advanced turbine design for coal-fueled engines. Phase 1, Erosion of turbine hot gas path blading: Final report

    SciTech Connect

    Wagner, J.H.; Johnson, B.V.

    1993-04-01

    The investigators conclude that: (1) Turbine erosion resistance was shown to be improved by a factor of 5 by varying the turbine design. Increasing the number of stages and increasing the mean radius reduces the peak predicted erosion rates for 2-D flows on the blade airfoil from values which are 6 times those of the vane to values of erosion which are comparable to those of the vane airfoils. (2) Turbine erosion was a strong function of airfoil shape depending on particle diameter. Different airfoil shapes for the same turbine operating condition resulted in a factor of 7 change in airfoil erosion for the smallest particles studied (5 micron). (3) Predicted erosion for the various turbines analyzed was a strong function of particle diameter and weaker function of particle density. (4) Three dimensional secondary flows were shown to cause increases in peak and average erosion on the vane and blade airfoils. Additionally, the interblade secondary flows and stationary outer case caused unique erosion patterns which were not obtainable with 2-D analyses. (5) Analysis of the results indicate that hot gas cleanup systems are necessary to achieve acceptable turbine life in direct-fired, coal-fueled systems. In addition, serious consequences arise when hot gas filter systems fail for even short time periods. For a complete failure of the filter system, a 0.030 in. thick corrosion-resistant protective coating on a turbine blade would be eroded at some locations within eight minutes.

  12. Turbojet engine blade damping

    NASA Technical Reports Server (NTRS)

    Srinivasan, A. V.; Cutts, D. G.; Sridhar, S.

    1981-01-01

    The potentials of various sources of nonaerodynamic damping in engine blading are evaluated through a combination of advanced analysis and testing. The sources studied include material hysteresis, dry friction at shroud and root disk interfaces as well as at platform type external dampers. A limited seris of tests was conducted to evaluate damping capacities of composite materials (B/AL, B/AL/Ti) and thermal barrier coatings. Further, basic experiments were performed on titanium specimens to establish the characteristics of sliding friction and to determine material damping constants J and n. All the tests were conducted on single blades. Mathematical models were develthe several mechanisms of damping. Procedures to apply this data to predict damping levels in an assembly of blades are developed and discussed.

  13. Fluid blade disablement tool

    DOEpatents

    Jakaboski, Juan-Carlos; Hughs, Chance G.; Todd, Steven N.

    2012-01-10

    A fluid blade disablement (FBD) tool that forms both a focused fluid projectile that resembles a blade, which can provide precision penetration of a barrier wall, and a broad fluid projectile that functions substantially like a hammer, which can produce general disruption of structures behind the barrier wall. Embodiments of the FBD tool comprise a container capable of holding fluid, an explosive assembly which is positioned within the container and which comprises an explosive holder and explosive, and a means for detonating. The container has a concavity on the side adjacent to the exposed surface of the explosive. The position of the concavity relative to the explosive and its construction of materials with thicknesses that facilitate inversion and/or rupture of the concavity wall enable the formation of a sharp and coherent blade of fluid advancing ahead of the detonation gases.

  14. Reference Operational Concepts for Advanced Nuclear Power Plants

    SciTech Connect

    Hugo, Jacques Victor; Farris, Ronald Keith

    2015-09-01

    This report represents the culmination of a four-year research project that was part of the Instrumentation and Control and Human Machine Interface subprogram of the DOE Advanced Reactor Technologies program.

  15. Advanced Turbine Systems Program industrial system concept development

    SciTech Connect

    Gates, S.

    1995-10-01

    The objective of Phase II of the Advanced Turbine Systems Program is to develop conceptual designs of gas fired advanced turbine systems that can be adapted for operation on coal and biomass fuels. The technical, economic, and environmental performance operating on natural gas and in a coal fueled mode is to be assessed. Detailed designs and test work relating to critical components are to be completed and a market study is to be conducted.

  16. Advances in pathogenic concepts and therapeutic agents in Rasmussen's encephalitis.

    PubMed

    Bien, Christian G; Elger, Christian E; Wiendl, Heinz

    2002-07-01

    Rasmussen's encephalitis is a rare inflammatory brain disease which occurs mainly in children and is characterised by affection of only one hemisphere. Pathogenetic concepts have considered three different, not mutually exclusive, key factors contributing to the initiating or perpetuating events in the central nervous system. These include viruses, autoimmune antibodies and autoimmune cytotoxic T lymphocytes. Based on these concepts, different therapeutic strategies have been pursued, such as antiviral agents, plasmapheresis, immuno-adsorption, immunosuppression or immunomodulation with intravenous immunoglobulins. However, due to the lack of larger studies, to date there is no established therapeutic strategy of this devastating disease. An overview of the current state of immunepathogenic concepts for Rasmussen's encephalitis is given and past and present treatment attempts are discussed, including an outline of future perspectives. An opinion on symptomatic treatment with anticonvulsive drugs is included. PMID:12084008

  17. Advanced radiator concepts utilizing honeycomb panel heat pipes (stainless steel)

    NASA Technical Reports Server (NTRS)

    Fleischman, G. L.; Tanzer, H. J.

    1985-01-01

    The feasibility of fabricating and processing moderate temperature range heat pipes in a low mass honeycomb sandwich panel configuration for highly efficient radiator fins for the NASA space station was investigated. A variety of honeycomb panel facesheet and core-ribbon wick concepts were evaluated within constraints dictated by existing manufacturing technology and equipment. Concepts evaluated include: type of material, material and panel thicknesses, wick type and manufacturability, liquid and vapor communication among honeycomb cells, and liquid flow return from condenser to evaporator facesheet areas. In addition, the overall performance of the honeycomb panel heat pipe was evaluated analytically.

  18. Advanced transportation concept for round-trip space travel

    NASA Technical Reports Server (NTRS)

    Yen, Chen-Wan L.

    1988-01-01

    A departure from the conventional concept of round-trip space travel is introduced. It is shown that a substantial reduction in the initial load required of the Shuttle or other launch vehicle can be achieved by staging the ascent orbit and leaving fuel for the return trip at each stage of the orbit. Examples of round trips from a low-inclination LEO to a high-inclination LEO and from an LEO to a GEO are used to show the merits of the new concept. Potential problem areas and research needed for the development of an efficient space transportation network are discussed.

  19. Advanced turboprop aircraft flyover noise: Annoyance to counter-rotating-propeller configurations with an equal number of blades on each rotor, preliminary results

    NASA Technical Reports Server (NTRS)

    Mccurdy, David A.

    1988-01-01

    A laboratory experiment was conducted to quantify the annoyance of people to the flyover noise of advanced turboprop aircraft with counter-rotating propellers (CRP) having an equal number of blades on each rotor. The objectives were: to determine the effects of total content on annoyance; and compare annoyance to n x n CRP advanced turboprop aircraft with annoyance to conventional turboprop and jet aircraft. A computer synthesis system was used to generate 27 realistic, time-varying simulations of advanced turboprop takeoff noise in which the tonal content was systematically varied to represent the factorial combinations of nine fundamental frequencies and three tone-to-broadband noise ratios. These advanced turboprop simulations along with recordings of five conventional turboprop takeoffs and five conventional jet takeoffs were presented at three D-weighted sound pressure levels to 64 subjects in an anechoic chamber. Analyses of the subjects' annoyance judgments compare the three aircraft types and examined the effects of the differences in tonal content among the advanced turboprop noises. The annoyance prediction ability of various noise metrics is also examined.

  20. Technological advances in perioperative monitoring: Current concepts and clinical perspectives

    PubMed Central

    Chilkoti, Geetanjali; Wadhwa, Rachna; Saxena, Ashok Kumar

    2015-01-01

    Minimal mandatory monitoring in the perioperative period recommended by Association of Anesthetists of Great Britain and Ireland and American Society of Anesthesiologists are universally acknowledged and has become an integral part of the anesthesia practice. The technologies in perioperative monitoring have advanced, and the availability and clinical applications have multiplied exponentially. Newer monitoring techniques include depth of anesthesia monitoring, goal-directed fluid therapy, transesophageal echocardiography, advanced neurological monitoring, improved alarm system and technological advancement in objective pain assessment. Various factors that need to be considered with the use of improved monitoring techniques are their validation data, patient outcome, safety profile, cost-effectiveness, awareness of the possible adverse events, knowledge of technical principle and ability of the convenient routine handling. In this review, we will discuss the new monitoring techniques in anesthesia, their advantages, deficiencies, limitations, their comparison to the conventional methods and their effect on patient outcome, if any. PMID:25788767

  1. Parachute systems technology: Fundamentals, concepts, and applications: Advanced parachute design

    SciTech Connect

    Peterson, C.W.; Johnson, D.W.

    1987-01-01

    Advances in high-performance parachute systems and the technologies needed to design them are presented in this paper. New parachute design and performance prediction codes are being developed to assist the designer in meeting parachute system performance requirements after a minimum number of flight tests. The status of advanced design codes under development at Sandia National Laboratories is summarized. An integral part of parachute performance prediction is the rational use of existing test data. The development of a data base for parachute design has been initiated to illustrate the effects of inflated diameter, geometric porosity, reefing line length, suspension line length, number of gores, and number of ribbons on parachute drag. Examples of advancements in parachute materials are presented, and recent problems with Mil-Spec broadgoods are reviewed. Finally, recent parachute systems tested at Sandia are summarized to illustrate new uses of old parachutes, new parachute configurations, and underwater recovery of payloads.

  2. Low-Noise Rotorcraft Blades

    NASA Technical Reports Server (NTRS)

    Brooks, Thomas F.

    1994-01-01

    Blades of helicopter rotors, tilt rotors, and like reshaped to reduce noise, according to proposal. Planform features combination of rearward and forward sweep. Forward sweep over large outer portion of blade constitutes primary noise-reduction feature. Relieves some of compressive effect in tip region, with consequent reduction of noise from compressive sources. Performance at high advance ratio improved. Cabin vibration and loading noise reduced by load-averaging effect of double-sweep planform. Aft-swept section provides balancing of aerodynamic and other dynamic forces on blade along 1/4-chord line of straight inboard section and along projection of line to outermost blade radius. Possible for hub-hinge forces and moments to remain within practical bounds. Provides stabilizing blade forces and moments to counteract any instability caused by forward sweep.

  3. Ultra-Efficient Engine Technology (UEET), Proof of Concept Compressor, Advanced Compressor Casing T

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Ultra-Efficient Engine Technology (UEET), Proof of Concept Compressor, Advanced Compressor Casing Treatment testing; close up - throttle valve -wide open; oil and air lines plus instrumentation between collector and gearbox.

  4. Methodological Advances in the Study of Self-Concept.

    ERIC Educational Resources Information Center

    Schwartz, Terrence J.

    Critical review of previous techniques for the measurement of an individual's self-concept (SC) is a necessary prelude to the development of more adequate methodologies. This paper focuses on recent methodological innovations in the study of the self, namely, those derived from cognitive social psychology. A view of the self as a cognitive…

  5. Advanced Level Physics Students' Conceptions of Quantum Physics.

    ERIC Educational Resources Information Center

    Mashhadi, Azam

    This study addresses questions about particle physics that focus on the nature of electrons. Speculations as to whether they are more like particles or waves or like neither illustrate the difficulties with which students are confronted when trying to incorporate the concepts of quantum physics into their overall conceptual framework. Such…

  6. Report on the Lake Arrowhead workshop on advanced acceleration concepts

    SciTech Connect

    Pellegrini, C.

    1989-03-01

    We review the present status of the field of New Acceleration Concepts, as presented at the Lake Arrowhead workshop, held at the beginning of 1989. Many new and promising results have been obtained recently, and the field is actively developing. We discuss briefly some of the main results presented at the workshop. 43 refs., 2 tabs.

  7. Concept selection for advanced low-emission coal fired boiler

    SciTech Connect

    Gorrell, R.L.; Rodgers, L.W.; Farthing, G.A.

    1993-12-31

    The Babcock & Wilcox Company (B&W), under contract to the US Department of Energy (DOE) with subcontract to Physical Sciences, Inc. (PSIT), the Massachusetts Institute of Technology (MIT) and United Engineers and Constructors (UE&C) has begun development of an advanced low-emission boiler system (LEBS). The initial phase of this multi-phase program required a thorough review and assessment of potential advanced technologies and techniques for control of combustion and flue gas emissions. Results of this assessment are presented in this paper.

  8. Summary of the advanced high efficiency concepts subcontractors review meeting

    SciTech Connect

    Not Available

    1983-10-01

    Brief summaries are given of presentations on the topics of: new ideas for photovoltaic conversion; a high efficiency bulk graded band gap/pn junction solar cell structure at high concentration ratios; development of high efficiency graded band gap p+-p-n GaAlAs/GaAs solar cells; an advanced AlGaAs-GaAs high efficiency concentrator solar cell; GaAs solar cell with low surface recombination; theory of advanced high-efficiency concentrator cells; III-V high efficiency photovoltaic cells; advanced high efficiency concentrator cells; monolithic two-color/three-terminal GaAsP/GaAsSb solar cells; high-efficiency thin-film and multijunction solar cells; review of the NASA space photovoltaic program; review of the Air Force space photovoltaic program; the Air Force manufacturing program; an overview of Sandia FY84 advanced concentrator cell research; thin film gallium arsenide solar cell research; fabrication of monocrystalline GaAs solar cells utilizing sacrificial NaCl substrates; and progress toward development of high efficiency GaAs solar cells on silicon substrates. (LEW)

  9. Study of advanced fuel system concepts for commercial aircraft

    NASA Technical Reports Server (NTRS)

    Coffinberry, G. A.

    1985-01-01

    An analytical study was performed in order to assess relative performance and economic factors involved with alternative advanced fuel systems for future commercial aircraft operating with broadened property fuels. The DC-10-30 wide-body tri-jet aircraft and the CF6-8OX engine were used as a baseline design for the study. Three advanced systems were considered and were specifically aimed at addressing freezing point, thermal stability and lubricity fuel properties. Actual DC-10-30 routes and flight profiles were simulated by computer modeling and resulted in prediction of aircraft and engine fuel system temperatures during a nominal flight and during statistical one-day-per-year cold and hot flights. Emergency conditions were also evaluated. Fuel consumption and weight and power extraction results were obtained. An economic analysis was performed for new aircraft and systems. Advanced system means for fuel tank heating included fuel recirculation loops using engine lube heat and generator heat. Environmental control system bleed air heat was used for tank heating in a water recirculation loop. The results showed that fundamentally all of the three advanced systems are feasible but vary in their degree of compatibility with broadened-property fuel.

  10. Advance Approach to Concept and Design Studies for Space Missions

    NASA Technical Reports Server (NTRS)

    Deutsch, M.; Nichols, J.

    1999-01-01

    Recent automated and advanced techniques developed at JPL have created a streamlined and fast-track approach to initial mission conceptualization and system architecture design, answering the need for rapid turnaround of trade studies for potential proposers, as well as mission and instrument study groups.

  11. Fostering Visions for the Future: A Review of the NASA Institute for Advanced Concepts

    NASA Technical Reports Server (NTRS)

    2009-01-01

    The NASA Institute for Advanced Concepts (NIAC) was formed in 1998 to provide an independent source of advanced aeronautical and space concepts that could dramatically impact how NASA develops and conducts its missions. Until the program's termination in August 2007, NIAC provided an independent open forum, a high-level point of entry to NASA for an external community of innovators, and an external capability for analysis and definition of advanced aeronautics and space concepts to complement the advanced concept activities conducted within NASA. Throughout its 9-year existence, NIAC inspired an atmosphere for innovation that stretched the imagination and encouraged creativity. As requested by Congress, this volume reviews the effectiveness of NIAC and makes recommendations concerning the importance of such a program to NASA and to the nation as a whole, including the proper role of NASA and the federal government in fostering scientific innovation and creativity and in developing advanced concepts for future systems. Key findings and recommendations include that in order to achieve its mission, NASA must have, and is currently lacking, a mechanism to investigate visionary, far-reaching advanced concepts. Therefore, a NIAC-like entity should be reestablished to fill this gap.

  12. Recent advances in approximation concepts for optimum structural design

    NASA Technical Reports Server (NTRS)

    Barthelemy, Jean-Francois M.; Haftka, Raphael T.

    1991-01-01

    The basic approximation concepts used in structural optimization are reviewed. Some of the most recent developments in that area since the introduction of the concept in the mid-seventies are discussed. The paper distinguishes between local, medium-range, and global approximations; it covers functions approximations and problem approximations. It shows that, although the lack of comparative data established on reference test cases prevents an accurate assessment, there have been significant improvements. The largest number of developments have been in the areas of local function approximations and use of intermediate variable and response quantities. It also appears that some new methodologies are emerging which could greatly benefit from the introduction of new computer architecture.

  13. An advanced concept that promises ecological and economic viability

    NASA Technical Reports Server (NTRS)

    Wright, B. R.; Sedgwick, T. A.; Urie, D. M.

    1976-01-01

    The actuality of supersonic commercial service being provided by Concorde is demonstrating to the world the advantages offered by supersonic travel for both business and recreation. Public acceptance will gradually and persistently stimulate interest to proceed with a second generation design that meets updated economic and ecological standards. It is estimated that this concept could operate profitably on world-wide routes with a revenue structure based upon economy fares. Airplanes will meet all present day ecological requirements regarding noise and emissions.

  14. Containment of composite fan blades

    NASA Technical Reports Server (NTRS)

    Stotler, C. L.; Coppa, A. P.

    1979-01-01

    A lightweight containment was developed for turbofan engine fan blades. Subscale ballistic-type tests were first run on a number of concepts. The most promising configuration was selected and further evaluated by larger scale tests in a rotating test rig. Weight savings made possible by the use of this new containment system were determined and extrapolated to a CF6-size engine. An analytical technique was also developed to predict the released blades motion when involved in the blade/casing interaction process. Initial checkout of this procedure was accomplished using several of the tests run during the program.

  15. Concept for advanced satellite communications and required technologies

    NASA Technical Reports Server (NTRS)

    Ramler, J. R.; Salzman, J. A.

    1982-01-01

    The advanced communications technology satellite (ACTS) program of NASA is aimed at the development of high risk technologies that will enable exploiting higher frequency bands and techniques for improving frequency reuse. The technologies under development include multiple beam spacecraft antennas, on-board switching and processing, RF devices and components and advanced earth stations. The program focus is on the Ka-band (30/20 GHz) as the implementing frequency since it has five times the bandwidth of either the C- or Ku-bands. However, the technology being developed is applicable to other frequency bands as well and will support a wide range of future communications systems required by NASA, other Government agencies and the commercial sector. An overview is presented of an operational 30/20 GHz satellite system that may evolve. How the system addresses service requirements is discussed, and the technology required and being developed is considered. Previously announced in STAR as N83-11210

  16. Concept for advanced satellite communications and required technologies

    NASA Technical Reports Server (NTRS)

    Ramler, J. R.; Salzman, J. A.

    1982-01-01

    The advanced communications technology satellite (ACTS) program of NASA is aimed at the development of high risk technologies that will enable exploiting higher frequency bands and techniques for improving frequency reuse. The technologies under development include multiple beam spacecraft antennas, on-board switching and processing, RF devices and components and advanced Earth stations. The program focus is on the Ka-band (30/20 GHz) as the implementing frequency since it has five times the bandwidth of either the C- or Ku-bands. However, the technology being developed is applicable to other frequency bands as well and will support a wide range of future communications systems required by NASA, other Government agencies and the commercial sector. An overview is presented of an operational 30/20 GHz satellite system that may evolve. How the system addresses service requirements is discussed, and the technology required and being developed is considered.

  17. Evaluation of ADAM/1 model for advanced coal extraction concepts

    NASA Technical Reports Server (NTRS)

    Deshpande, G. K.; Gangal, M. D.

    1982-01-01

    Several existing computer programs for estimating life cycle cost of mining systems were evaluated. A commercially available program, ADAM/1 was found to be satisfactory in relation to the needs of the advanced coal extraction project. Two test cases were run to confirm the ability of the program to handle nonconventional mining equipment and procedures. The results were satisfactory. The model, therefore, is recommended to the project team for evaluation of their conceptual designs.

  18. Experimental aerodynamic performance of advanced 40 deg-swept 10-blade propeller model at Mach 0.6 to 0.85

    NASA Technical Reports Server (NTRS)

    Mitchell, Glenn A.

    1988-01-01

    A propeller designated as SR-6, designed with 40 deg of sweep and 10 blades to cruise at Mach 0.8 at an altitude of 10.7 km (35,000 ft), was tested in the NASA Lewis Research Center's 8- by 6-Foot Wind Tunnel. This propeller was one of a series of advanced single rotation propeller models designed and tested as part of the NASA Advanced Turboprop Project. Design-point net efficiency was almost constant to Mach 0.75 but fell above this speed more rapidly than that of any previously tested advanced propeller. Alternative spinners that further reduced the near-hub interblade Mach numbers and relieved the observed hub choking improved performance above Mach 0.75. One spinner attained estimated SR-6 Design-point net deficiencies of 80.6 percent at Mach 0.75 and 79.2 percent at Mach 0.8, higher than the measured performance of any previously tested advanced single-rotation propeller at these speeds.

  19. ADVANCED DIRECT LIQUEFACTION CONCEPTS FOR PETC GENERIC UNITS

    SciTech Connect

    Adam J. Berkovich

    2001-08-01

    The results of Laboratory and Bench-Scale experiments and supporting technical and economic assessments conducted under DOE Contract No. DE-AC22-91PC91040 are reported for the period April 1, 2001 to June 30 2001. This work involves the introduction into the basic two-stage liquefaction process several novel concepts, which include dispersed lower-cost catalysts, coal cleaning by oil agglomeration, and distillate hydrotreating and dewaxing. This project has been modified to include an investigation into the production of value added materials from coal using low-severity liquefaction based technologies.

  20. ADVANCED DIRECT LIQUEFACTION CONCEPTS FOR PETC GENERIC UNITS

    SciTech Connect

    Adam J. Berkovich

    2001-11-01

    The results of Laboratory and Bench-Scale experiments and supporting technical and economic assessments conducted under DOE Contract No. DE-AC22-91PC91040 are reported for the period July 1, 2001 to September 30 2001. This work involves the introduction into the basic two-stage liquefaction process several novel concepts, which include dispersed lower-cost catalysts, coal cleaning by oil agglomeration, and distillate hydrotreating and dewaxing. This project has been modified to include an investigation into the production of value added materials from coal using low-severity liquefaction based technologies.

  1. ADVANCED DIRECT LIQUEFACTION CONCEPTS FOR PETC GENERIC UNITS

    SciTech Connect

    Adam J. Berkovich

    2000-03-01

    The results of Laboratory and Bench-Scale experiments and supporting technical and economic assessments conducted under DOE Contract No. DE-AC22-91PC91040 is reported for the period April 1, 1998 to June 30, 1998. This contract is with the University of kentucky Research Foundation, which supports work with the University of Kentucky Center for Applied Energy Researc, CONSOL, Inc., LDP Associates, and Hydrocarbon Technologies, Inc. This work involves the introduction into the basic two-stage liquefaction process several novel concepts, which include dispersed lower-cost catalysts, coal cleaning by oil agglomeration, and distillate hydrotreating and dewaxing.

  2. Advanced Direct Liquefaction Concepts for PETC Generic Units - Phase II

    SciTech Connect

    1997-02-01

    Reported here are the results of Laboratory and Bench-Scale experiments and supporting technical and economic assessments conducted under DOE Contract No. DE-AC22-91PC9104O during the period October 1, 1996 to December 31, 1996. This contract is with the University of Kentucky Research Foundation which supports work with the University of Kentucky Center for Applied Energy Research, CONSOI+ Inc., LDP Associates, and Hydrocarbon Technologies, Inc. This work invoives the introduction into the basic two stage liquefaction process several novel concepts which include dispersed lower-cost catalysts, coal cleaning by oil agglomeration, and distillate hydrotreating and dewaxing.

  3. Commercial space opportunities - Advanced concepts and technology overview

    NASA Technical Reports Server (NTRS)

    Reck, Gregory M.

    1993-01-01

    The paper discusses the status of current and future commercial space opportunities. The goal is to pioneer innovative, customer-focused space concepts and technologies, leveraged through industrial, academic, and government alliance, to ensure U.S. commercial competitiveness and preeminence in space. The strategy is to develop technologies which enable new products and processes, deploy existing technology into commercial and military products and processes, and integrate military and commercial research and production activities. Technology development areas include information infrastructure, electronics design and manufacture, health care technology, environment technology, and aeronautical technologies.

  4. Advanced supersonic technology concept study: Hydrogen fueled configuration

    NASA Technical Reports Server (NTRS)

    Brewer, G. D.

    1974-01-01

    Conceptual designs of hydrogen fueled supersonic transport configurations for the 1990 time period were developed and compared with equivalent technology Jet A-1 fueled vehicles to determine the economic and performance potential of liquid hydrogen as an alternate fuel. Parametric evaluations of supersonic cruise vehicles with varying design and transport mission characteristics established the basis for selecting a preferred configuration which was then studied in greater detail. An assessment was made of the general viability of the selected concept including an evaluation of costs and environmental considerations, i.e., exhaust emissions and sonic boom characteristics. Technology development requirements and suggested implementation schedules are presented.

  5. ADVANCED DIRECT LIQUEFACTION CONCEPTS FOR PETC GENERIC UNITS

    SciTech Connect

    Adam J. Berkovich

    2001-04-01

    The results of Laboratory and Bench-Scale experiments and supporting technical and economic assessments conducted under DOE Contract No. DE-AC22-91PC91040 are reported for the period January 1, 2001 to March 31 2001. This work involves the introduction into the basic two-stage liquefaction process several novel concepts, which include dispersed lower-cost catalysts, coal cleaning by oil agglomeration, and distillate hydrotreating and dewaxing. This project has been modified to include an investigation into the production of value added materials from coal using low-severity liquefaction based technologies.

  6. Counterrotating aircraft propulsor blades

    NASA Technical Reports Server (NTRS)

    Nelson, Joey L. (Inventor); Elston, III, Sidney B. (Inventor); Tseng, Wu-Yang (Inventor); Hemsworth, Martin C. (Inventor)

    1993-01-01

    A propulsor blade for an aircraft engine includes an airfoil section formed in the shape of a scimitar. A metallic blade spar is interposed between opposed surfaces of the blade and is bonded to the surfaces to establish structural integrity of the blade. The metallic blade spar includes a root end allowing attachment of the blade to the engine.

  7. Counterrotating aircraft propulsor blades

    NASA Technical Reports Server (NTRS)

    Nelson, Joey L. (Inventor); Elston, III, Sidney B. (Inventor); Tseng, Wu-Yang (Inventor); Hemsworth, Martin C. (Inventor)

    1988-01-01

    A propulsor blade for an aircraft engine includes an airfoil section formed in the shape of a scimitar. A metallic blade spar is interposed between opposed surfaces of the blade and is bonded to the surfaces to establish structural integrity of the blade. The metallic blade spar includes a root end allowing attachment of the blade to the engine.

  8. Advanced radiator concepts utilizing honeycomb panel heat pipes

    NASA Astrophysics Data System (ADS)

    Fleischman, G. L.; Peck, S. J.; Tanzer, H. J.

    1987-10-01

    The feasibility of fabricating and processing moderate temperature range vapor chamber type heat pipes in a low mass honeycomb panel configuration for highly efficient radiator fins for potential use on the space station was investigated. A variety of honeycomb panel facesheet and core-ribbon wick concepts were evaluated within constraints dictated by existing manufacturing technology and equipment. Concepts evaluated include type of material, material and panel thickness, wick type and manufacturability, liquid and vapor communication among honeycomb cells, and liquid flow return from condenser to evaporator facesheet areas. A thin-wall all-welded stainless steel design with methanol as the working fluid was the initial prototype unit. It was found that an aluminum panel could not be fabricated in the same manner as a stainless steel panel due to diffusion bonding and resistance welding considerations. Therefore, a formed and welded design was developed. The prototype consists of ten panels welded together into a large panel 122 by 24 by 0.15 in., with a heat rejection capability of 1000 watts and a fin efficiency of essentially 1.0.

  9. Measurement of the steady surface pressure distribution on a single rotation large scale advanced prop-fan blade at Mach numbers from 0.03 to 0.78

    NASA Technical Reports Server (NTRS)

    Bushnell, Peter

    1988-01-01

    The aerodynamic pressure distribution was determined on a rotating Prop-Fan blade at the S1-MA wind tunnel facility operated by the Office National D'Etudes et de Recherches Aerospatiale (ONERA) in Modane, France. The pressure distributions were measured at thirteen radial stations on a single rotation Large Scale Advanced Prop-Fan (LAP/SR7) blade, for a sequence of operating conditions including inflow Mach numbers ranging from 0.03 to 0.78. Pressure distributions for more than one power coefficient and/or advanced ratio setting were measured for most of the inflow Mach numbers investigated. Due to facility power limitations the Prop-Fan test installation was a two bladed version of the eight design configuration. The power coefficient range investigated was therefore selected to cover typical power loading per blade conditions which occur within the Prop-Fan operating envelope. The experimental results provide an extensive source of information on the aerodynamic behavior of the swept Prop-Fan blade, including details which were elusive to current computational models and do not appear in the two-dimensional airfoil data.

  10. New virtual laboratories presenting advanced motion control concepts

    NASA Astrophysics Data System (ADS)

    Goubej, Martin; Krejčí, Alois; Reitinger, Jan

    2015-11-01

    The paper deals with development of software framework for rapid generation of remote virtual laboratories. Client-server architecture is chosen in order to employ real-time simulation core which is running on a dedicated server. Ordinary web browser is used as a final renderer to achieve hardware independent solution which can be run on different target platforms including laptops, tablets or mobile phones. The provided toolchain allows automatic generation of the virtual laboratory source code from the configuration file created in the open- source Inkscape graphic editor. Three virtual laboratories presenting advanced motion control algorithms have been developed showing the applicability of the proposed approach.

  11. Forward sweep, low noise rotor blade

    NASA Technical Reports Server (NTRS)

    Brooks, Thomas F. (Inventor)

    1996-01-01

    A forward-swept, low-noise rotor blade includes an inboard section, an aft-swept section and a forward-swept outboard section. The rotor blade reduces the noise of rotorcraft, including both standard helicopters and advanced systems such as tiltrotors. The primary noise reduction feature is the forward sweep of the planform over a large portion of the outer blade radius. The rotor blade also includes an aft-swept section. The purpose of the aft-swept region is to provide a partial balance to pitching moments produced by the outboard forward-swept portion of the blade. The rotor blade has a constant chord width; or has a chord width which decreases linearly along the entire blade span; or combines constant and decreasing chord widths, wherein the blade is of constant chord width from the blade root to a certain location on the rotor blade, then decreases linearly to the blade tip thereafter. The noise source showing maximum noise reduction is blade-vortex interaction (BVI) noise. Also reduced are thickness, noise, high speed impulsive noise, cabin vibration and loading noise.

  12. Proof-of-concept and advancement of the CellFlux concept

    NASA Astrophysics Data System (ADS)

    Odenthal, Christian; Steinmann, Wolf-Dieter

    2016-05-01

    The CellFlux storage system is a new concept for reducing the costs of medium to high temperature thermal energy storage. Initially designed for solar thermal power plants, the concept is suitable for industrial processes and power to heat applications as well. This paper gives first results of a new pilot scale plant set up at DLR in Stuttgart as a proof of concept. Experimental results are used for the validation of a simplified model. The model is apllied to calculate pareto optimal storage configurations in terms of necessary storage mass and exergetic efficiency, suitable for two types of solar thermal power plants. Particularly for applications having larger temperature differences, high exergetic efficiencies at low costs for the storage material can be achieved.

  13. Engine Concept Study for an Advanced Single-Aisle Transport

    NASA Technical Reports Server (NTRS)

    Guynn, Mark D.; Berton, Jeffrey J.; Fisher, Kenneth L.; Haller, William J.; Tong, Michael; Thurman, Douglas R.

    2009-01-01

    The desire for higher engine efficiency has resulted in the evolution of aircraft gas turbine engines from turbojets, to low bypass ratio, first generation turbofans, to today's high bypass ratio turbofans. Although increased bypass ratio has clear benefits in terms of propulsion system metrics such as specific fuel consumption, these benefits may not translate into aircraft system level benefits due to integration penalties. In this study, the design trade space for advanced turbofan engines applied to a single aisle transport (737/A320 class aircraft) is explored. The benefits of increased bypass ratio and associated enabling technologies such as geared fan drive are found to depend on the primary metrics of interest. For example, bypass ratios at which mission fuel consumption is minimized may not require geared fan technology. However, geared fan drive does enable higher bypass ratio designs which result in lower noise. The results of this study indicate the potential for the advanced aircraft to realize substantial improvements in fuel efficiency, emissions, and noise compared to the current vehicles in this size class.

  14. From bacterial genomics to metagenomics: concept, tools and recent advances.

    PubMed

    Sharma, Pooja; Kumari, Hansi; Kumar, Mukesh; Verma, Mansi; Kumari, Kirti; Malhotra, Shweta; Khurana, Jitendra; Lal, Rup

    2008-06-01

    In the last 20 years, the applications of genomics tools have completely transformed the field of microbial research. This has primarily happened due to revolution in sequencing technologies that have become available today. This review therefore, first describes the discoveries, upgradation and automation of sequencing techniques in a chronological order, followed by a brief discussion on microbial genomics. Some of the recently sequenced bacterial genomes are described to explain how complete genome data is now being used to derive interesting findings. Apart from the genomics of individual microbes, the study of unculturable microbiota from different environments is increasingly gaining importance. The second section is thus dedicated to the concept of metagenomics describing environmental DNA isolation, metagenomic library construction and screening methods to look for novel and potentially important genes, enzymes and biomolecules. It also deals with the pioneering studies in the area of metagenomics that are offering new insights into the previously unappreciated microbial world. PMID:23100712

  15. ADVANCED DIRECT LIQUEFACTION CONCEPTS FOR PETC GENERIC UNITS

    SciTech Connect

    Adam J. Berkovich

    2000-02-01

    The results of Laboratory and Bench-Scale experiments and supporting technical and economic assessments conducted under DOE Contract No. DE-AC22-91PC91040 is reported for the period July 1, 1998 to September 30, 1998. This contract is with the University of kentucky Research Foundation, which supports work with the University of Kentucky Center for Applied Energy Researc, CONSOL, Inc., LDP Associates, and Hydrocarbon Technologies, Inc. This work involves the introduction into the basic two-stage liquefaction process several novel concepts, which include dispersed lower-cost catalysts, coal cleaning by oil agglomeration, and distillate hydrotreating and dewaxing. This project has been modified to include an investigation into the production of value added materials from coal using liquefaction based technologies.

  16. Advanced Turbine Systems Program industrial system concept development

    SciTech Connect

    Gates, S.

    1995-12-31

    Solar approached Phase II of ATS program with the goal of 50% thermal efficiency. An intercolled and recuperated gas turbine was identified as the ultimate system to meet this goal in a commercial gas turbine environment. With commercial input from detailed market studies and DOE`s ATS program, Solar redefined the company`s proposed ATS to fit both market and sponsor (DOE) requirements. Resulting optimized recuperated gas turbine will be developed in two sizes, 5 and 15 MWe. It will show a thermal efficiency of about 43%, a 23% improvement over current industrial gas turbines. Other ATS goals--emissions, RAMD (reliability, availability, maintainability, durability), cost of power--will be met or exceeded. During FY95, advanced development of key materials, combustion and component technologies proceeded to the point of acceptance for inclusion in ATS Phase III.

  17. ADVANCED SULFUR CONTROL CONCEPTS FOR HOT-GAS DESULFURIZATION TECHNOLOGY

    SciTech Connect

    A. LOPEZ ORTIZ; D.P. HARRISON; F.R. GROVES; J.D. WHITE; S. ZHANG; W.-N. HUANG; Y. ZENG

    1998-10-31

    This research project examined the feasibility of a second generation high-temperature coal gas desulfurization process in which elemental sulfur is produced directly during the sorbent regeneration phase. Two concepts were evaluated experimentally. In the first, FeS was regenerated in a H2O-O2 mixture. Large fractions of the sulfur were liberated in elemental form when the H2O-O2 ratio was large. However, the mole percent of elemental sulfur in the product was always quite small (<<1%) and a process based on this concept was judged to be impractical because of the low temperature and high energy requirements associated with condensing the sulfur. The second concept involved desulfurization using CeO2 and regeneration of the sulfided sorbent, Ce2O2S, using SO2 to produce elemental sulfur directly. No significant side reactions were observed and the reaction was found to be quite rapid over the temperature range of 500°C to 700°C. Elemental sulfur concentrations (as S2) as large as 20 mol% were produced. Limitations associated with the cerium sorbent process are concentrated in the desulfurization phase. High temperature and highly reducing coal gas such as produced in the Shell gasification process are required if high sulfur removal efficiencies are to be achieved. For example, the equilibrium H2S concentration at 800°C from a Shell gas in contact with CeO2 is about 300 ppmv, well above the allowable IGCC specification. In this case, a two-stage desulfurization process using CeO2 for bulk H2S removal following by a zinc sorbent polishing step would be required. Under appropriate conditions, however, CeO2 can be reduced to non-stoichiometric CeOn (n<2) which has significantly greater affinity for H2S. Pre-breakthrough H2S concentrations in the range of 1 ppmv to 5 ppmv were measured in sulfidation tests using CeOn at 700°C in highly reducing gases, as measured by equilibrium O2 concentration, comparable to the Shell gas. Good sorbent durability was indicated in

  18. Diagnostic methods of a bladed disc mode shape evaluation used for shrouded blades in steam turbines

    NASA Astrophysics Data System (ADS)

    Strnad, Jaromir; Liska, Jindrich

    2015-11-01

    This paper deals with advanced methods for the evaluation of a bladed disc behavior in terms of the wheel vibration and blade service time consumption. These methods are developed as parts of the noncontact vibration monitoring system of the steam turbine shrouded blades. The proposed methods utilize the time-frequency processing (cross spectra) and the method using least squares to analyse the data from the optical and magnetoresistive sensors, which are mounted in the stator radially above the rotor blades. Fundamentally, the blade vibrations are detected during the blade passages under the sensors and the following signal processing, which covers also the proposed methods, leads to the estimation of the blade residual service life. The prototype system implementing above mentioned techniques was installed into the last stage of the new steam turbine (LP part). The methods for bladed disc mode shape evaluation were successfully verified on the signals, which were obtained during the commission operation of the turbine.

  19. Advanced concept considerations for STOL short-haul systems

    NASA Technical Reports Server (NTRS)

    Sweet, H. S.; Renshaw, J. H.

    1975-01-01

    Design, performance, and economic tradeoffs for STOL short-haul systems are presented. The analyses showed that quiet, short-field aircraft can be economically viable and provide benefits to airport congestion and to community noise relief. The objective of the studies was to compare and evaluate propulsive-lift systems and low-wing-loading aircraft provided with ride quality control and gust load alleviation, and to determine fuel consumption and cost tradeoffs, along with recommendations for development of technology, noise criteria, and airport planning. In the low density arena, the optimum aircraft sized for less than 50 passengers have active controls for ride quality and gust alleviation; turboprop propulsion offers significant cost and fuel saving with no appreciable block time penalty for the short typical stage lengths (on the order of 150 miles). In the high density arena, high bypass-ratio fan-powered aircraft, with design cruise speed of 0.7 to 0.75M and range capability to 1500 miles, are considered to be optimum. Field performance of 3000 feet or better can be achieved by the hybrid over-the-wing/internally blown flap concept with viable economics and low fuel consumption. Mechanical flap aircraft with high bypass-ratio engines are indicated to be superior for field lengths of 3500 feet or more. Technology development of propulsive lift is required, and further definition of the best fan-powered engine for low noise and low fuel consumption is needed.

  20. Advanced liquid Oxygen (LO2) propellant conditioning concept testing. 2

    NASA Technical Reports Server (NTRS)

    Hasting, J. H.; Perry, G. L. E.; Mehta, G. K.

    1996-01-01

    Extensive testing was performed on the promising L02 propellant conditioning concept of passive recirculation (no-bleed). Data from the project is being used to further anchor models in L02 conditioning behavior and broaden the data base of no-bleed and low-bleed conditioning. Data base expansion includes results from testing the limits of no-bleed and low-bleed conditioning with various configuration changes to the test facility and designed test article. Configuration changes include low velocity effects in the recirculation loop above the test article, test article internal constriction impacts, test article out-of-plane effects, impact from an actual Titan L02 pump attachment, feed duct slope effects, and up-leg booster effects. LN2 was used as the test fluid. The testing was conducted between July 1994 and January 1995 at the west test area of Marshall Space Flight Center. Data have shown that in most cases passive recirculation was demonstrated when the aforementioned limits were applied.

  1. Prescriptive concepts for advanced nuclear materials control and accountability systems

    SciTech Connect

    Whitty, W.J.; Strittmatter, R.B.; Ford, W.; Tisinger, R.M.; Meyer, T.H.

    1987-06-01

    Networking- and distributed-processing hardware and software have the potential of greatly enhancing nuclear materials control and accountability (MC and A) systems, from both safeguards and process operations perspectives, while allowing timely integrated safeguards activities and enhanced computer security at reasonable cost. A hierarchical distributed system is proposed consisting of groups of terminal and instruments in plant production and support areas connected to microprocessors that are connected to either larger microprocessors or minicomputers. These micros and/or minis are connected to a main machine, which might be either a mainframe or a super minicomputer. Data acquisition, preliminary input data validation, and transaction processing occur at the lowest level. Transaction buffering, resource sharing, and selected data processing occur at the intermediate level. The host computer maintains overall control of the data base and provides routine safeguards and security reporting and special safeguards analyses. The research described outlines the distribution of MC and A system requirements in the hierarchical system and distributed processing applied to MC and A. Implications of integrated safeguards and computer security concepts for the distributed system design are discussed. 10 refs., 4 figs.

  2. Advanced electric propulsion system concept for electric vehicles

    NASA Technical Reports Server (NTRS)

    Raynard, A. E.; Forbes, F. E.

    1979-01-01

    Seventeen propulsion system concepts for electric vehicles were compared to determine the differences in components and battery pack to achieve the basic performance level. Design tradeoffs were made for selected configurations to find the optimum component characteristics required to meet all performance goals. The anticipated performance when using nickel-zinc batteries rather than the standard lead-acid batteries was also evaluated. The two systems selected for the final conceptual design studies included a system with a flywheel energy storage unit and a basic system that did not have a flywheel. The flywheel system meets the range requirement with either lead-acid or nickel-zinc batteries and also the acceleration of zero to 89 km/hr in 15 s. The basic system can also meet the required performance with a fully charged battery, but, when the battery approaches 20 to 30 percent depth of discharge, maximum acceleration capability gradually degrades. The flywheel system has an estimated life-cycle cost of $0.041/km using lead-acid batteries. The basic system has a life-cycle cost of $0.06/km. The basic system, using batteries meeting ISOA goals, would have a life-cycle cost of $0.043/km.

  3. Advanced Nuclear Power Concepts for Human Exploration Missions

    SciTech Connect

    Robert L. Cataldo; Lee S. Mason

    2000-06-04

    The design reference mission for the National Aeronautics and Space Administration's (NASA's) human mission to Mars supports a philosophy of living off the land in order to reduce crew risk, launch mass, and life-cycle costs associated with logistics resupply to a Mars base. Life-support materials, oxygen, water, and buffer gases, and the crew's ascent-stage propellant would not be brought from Earth but rather manufactured from the Mars atmosphere. The propellants would be made over {approx}2 yr, the time between Mars mission launch window opportunities. The production of propellants is very power intensive and depends on type, amount, and time to produce the propellants. Closed-loop life support and food production are also power intensive. With the base having several habitats, a greenhouse, and propellant production capability, total power levels reach well over 125 kW(electric). The most mass-efficient means of satisfying these requirements is through the use of nuclear power. Studies have been performed to identify a potential system concept, described in this paper, using a mobile cart to transport the power system away from the Mars lander and provide adequate separation between the reactor and crew. The studies included an assessment of reactor and power conversion technology options, selection of system and component redundancy, determination of optimum separation distance, and system performance sensitivity to some key operating parameters.

  4. Advanced composite structural concepts and material technologies for primary aircraft structures

    NASA Technical Reports Server (NTRS)

    Jackson, Anthony

    1991-01-01

    Structural weight savings using advanced composites have been demonstrated for many years. Most military aircraft today use these materials extensively and Europe has taken the lead in their use in commercial aircraft primary structures. A major inhibiter to the use of advanced composites in the United States is cost. Material costs are high and will remain high relative to aluminum. The key therefore lies in the significant reduction in fabrication and assembly costs. The largest cost in most structures today is assembly. As part of the NASA Advanced Composite Technology Program, Lockheed Aeronautical Systems Company has a contract to explore and develop advanced structural and manufacturing concepts using advanced composites for transport aircraft. Wing and fuselage concepts and related trade studies are discussed. These concepts are intended to lower cost and weight through the use of innovative material forms, processes, structural configurations and minimization of parts. The approach to the trade studies and the downselect to the primary wing and fuselage concepts is detailed. The expectations for the development of these concepts is reviewed.

  5. RASC-AL (Revolutionary Aerospace Systems Concepts-Academic Linkage): 2002 Advanced Concept Design Presentation

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The Revolutionary Aerospace Systems Concepts-Academic Linkage (RASC-AL) is a program of the Lunar and Planetary Institute (LPI) in collaboration with the Universities Space Research Association's (USRA) ICASE institute through the NASA Langley Research Center. The RASC-AL key objectives are to develop relationships between universities and NASA that lead to opportunities for future NASA research and programs, and to develop aerospace systems concepts and technology requirements to enable future NASA missions. The program seeks to look decades into the future to explore new mission capabilities and discover what's possible. NASA seeks concepts and technologies that can make it possible to go anywhere, at anytime, safely, reliably, and affordably to accomplish strategic goals for science, exploration, and commercialization. University teams were invited to submit research topics from the following themes: Human and Robotic Space Exploration, Orbital Aggregation & Space Infrastructure Systems (OASIS), Zero-Emissions Aircraft, and Remote Sensing. RASC-AL is an outgrowth of the HEDS-UP (University Partners) Program sponsored by the LPI. HEDS-UP was a program of the Lunar and Planetary Institute designed to link universities with NASA's Human Exploration and Development of Space (HEDS) enterprise. The first RASC-AL Forum was held November 5-8, 2002, at the Hilton Cocoa Beach Oceanfront Hotel in Cocoa Beach, Florida. Representatives from 10 university teams presented student research design projects at this year's Forum. Each team contributed a written report and these reports are presented.

  6. Advanced direct coal liquefaction concepts. Final report, Volume 2

    SciTech Connect

    Berger, D.J.; Parker, R.J.; Simpson, P.L.

    1994-07-01

    Integration of innovative steps into new advanced processes have the potential to reduce costs for producing liquid fuels. In this program, objective is to develop a new approach to liquefaction that generates an all distillate product slate at a reduced cost of about US$25/barrel of crude oil equivalent. A Counterflow Reactor was developed in cooperation with GfK mbH, Germany. Advantages are low hydrogen recycle rates and low feed preheating requirements. Coal/heavy oil slurry is injected into the top of the reactor while the recycle gas and make up hydrogen is introduced into the bottom; hydrogenation products are withdrawn from the top. PU study resulted in distillable oil yields up to 74 wt % on feed (dry ash free) from coprocessing feed slurries containing 40 wt % Vesta subbituminous coal and 60 wt % Cold Lake heavy vacuum tower bottoms. Technologies developed separately by CED and ARC were combined. A 1-kg/hr integrated continuous flow bench scale unit was constructed at the ARC site in Devon, Alberta, based on modifications to a unit at Nisku, Alberta (the modified unit was used in the preliminary economic evaluation).

  7. Innovative Networking Concepts Tested on the Advanced Communications Technology Satellite

    NASA Technical Reports Server (NTRS)

    Friedman, Daniel; Gupta, Sonjai; Zhang, Chuanguo; Ephremides, Anthony

    1996-01-01

    This paper describes a program of experiments conducted over the advanced communications technology satellite (ACTS) and the associated TI-VSAT (very small aperture terminal). The experiments were motivated by the commercial potential of low-cost receive only satellite terminals that can operate in a hybrid network environment, and by the desire to demonstrate frame relay technology over satellite networks. The first experiment tested highly adaptive methods of satellite bandwidth allocation in an integrated voice-data service environment. The second involved comparison of forward error correction (FEC) and automatic repeat request (ARQ) methods of error control for satellite communication with emphasis on the advantage that a hybrid architecture provides, especially in the case of multicasts. Finally, the third experiment demonstrated hybrid access to databases and compared the performance of internetworking protocols for interconnecting local area networks (LANs) via satellite. A custom unit termed frame relay access switch (FRACS) was developed by COMSAT Laboratories for these experiments; the preparation and conduct of these experiments involved a total of 20 people from the University of Maryland, the University of Colorado and COMSAT Laboratories, from late 1992 until 1995.

  8. Some Advanced Concepts in Discrete Aerodynamic Sensitivity Analysis

    NASA Technical Reports Server (NTRS)

    Taylor, Arthur C., III; Green, Lawrence L.; Newman, Perry A.; Putko, Michele M.

    2003-01-01

    An efficient incremental iterative approach for differentiating advanced flow codes is successfully demonstrated on a two-dimensional inviscid model problem. The method employs the reverse-mode capability of the automatic differentiation software tool ADIFOR 3.0 and is proven to yield accurate first-order aerodynamic sensitivity derivatives. A substantial reduction in CPU time and computer memory is demonstrated in comparison with results from a straightforward, black-box reverse-mode applicaiton of ADIFOR 3.0 to the same flow code. An ADIFOR-assisted procedure for accurate second-rder aerodynamic sensitivity derivatives is successfully verified on an inviscid transonic lifting airfoil example problem. The method requires that first-order derivatives are calculated first using both the forward (direct) and reverse (adjoinct) procedures; then, a very efficient noniterative calculation of all second-order derivatives can be accomplished. Accurate second derivatives (i.e., the complete Hesian matrices) of lift, wave drag, and pitching-moment coefficients are calculated with respect to geometric shape, angle of attack, and freestream Mach number.

  9. Some Advanced Concepts in Discrete Aerodynamic Sensitivity Analysis

    NASA Technical Reports Server (NTRS)

    Taylor, Arthur C., III; Green, Lawrence L.; Newman, Perry A.; Putko, Michele M.

    2001-01-01

    An efficient incremental-iterative approach for differentiating advanced flow codes is successfully demonstrated on a 2D inviscid model problem. The method employs the reverse-mode capability of the automatic- differentiation software tool ADIFOR 3.0, and is proven to yield accurate first-order aerodynamic sensitivity derivatives. A substantial reduction in CPU time and computer memory is demonstrated in comparison with results from a straight-forward, black-box reverse- mode application of ADIFOR 3.0 to the same flow code. An ADIFOR-assisted procedure for accurate second-order aerodynamic sensitivity derivatives is successfully verified on an inviscid transonic lifting airfoil example problem. The method requires that first-order derivatives are calculated first using both the forward (direct) and reverse (adjoint) procedures; then, a very efficient non-iterative calculation of all second-order derivatives can be accomplished. Accurate second derivatives (i.e., the complete Hessian matrices) of lift, wave-drag, and pitching-moment coefficients are calculated with respect to geometric- shape, angle-of-attack, and freestream Mach number

  10. Selected advanced aerodynamic and active control concepts development

    NASA Technical Reports Server (NTRS)

    1981-01-01

    A task for the Energy Efficient Transport program conducted: (1) The design and wind tunnel development of high-aspect-ratio supercritical wings, investigating the cruise speed regime and also high-lift. (2) The preliminary design and evaluation of an aircraft combining a high-aspect-ratio supercritical wing with a winglet. (3) Active Controls: The determination of criteria, configuration, and flying qualities associated with augmented longitudinal stability of a level likely to be acceptable for the next generation transport; and the design of a practical augmentation system. The baseline against which the work was performed and evaluated was the Douglas DC-X-200 twin engine derivative of the DC-10 transport. The supercritical wing development showed that the cruise and buffet requirements could be achieved and that the wing could be designed to realize a sizable advantage over today's technology. Important advances in high lift performance were shown. The design study of an aircraft with supercritical wing and winglet suggested advantages in weight and fuel economy could be realized. The study of augmented stability, conducted with the aid of a motion base simulator, concluded that a negative static margin was acceptable for the baseline unaugmented aircraft.

  11. Atmospheric fluidized bed combustion advanced concept system. Final report

    SciTech Connect

    Not Available

    1992-05-01

    DONLEE Technologies Inc. is developing with support of the US Department of Energy an advanced circulating fluidized bed technology known as the Vortex{trademark} Fluidized Bed Combustor (VFBC). The unique feature of the VFBC is the injection of a significant portion of the combustion air into the cyclone. Since as much as one-half of the total combustion air is injected into the cyclone, the cross-sectional area of the circulating fluidized bed is considerably smaller than typical circulating fluidized beds. The technology is being developed for two applications: Industrial-scale boilers ranging from 20,000 to 100,000 pounds per hour steam generating capacity; and two-stage combustion in which a substoichiometric Vortex Fluidized Bed Combustor (2VFBC) or precombustor is used to generate a combustible gas for use primarily in boiler retrofit applications. This Level II analysis of these two applications indicates that both have merit. An industrial-scale VFBC boiler (60,000 lb/hr of steam) is projected to be economically attractive with coal prices as high as $40 per ton and gas prices between $4 and $5 per thousand cubic feet. The payback time is between 3 and 4 years. The 2VFBC system was evaluated at three capacities of application: 20,000; 60,000 and 100,000 lb/hr of steam. The payback times for these three capacities are 4.5, 2.1 and 1.55 years, respectively. The 2VFBC has potential applications for retrofit of existing pulverized coal-fired boilers or as a new large (utility) boiler. Pressurized operation of the 2VFBC has considerable potential for combined cycle power generation applications. Experimental development of both applications is presented here to demonstrate the potential of these two technologies.

  12. Periodic control of the individual-blade-control helicopter rotor

    NASA Technical Reports Server (NTRS)

    Mckillip, R. M., Jr.

    1985-01-01

    This paper describes the results of an investigation into methods of controller design for linear periodic systems utilizing an extension of modern control methods. Trends present in the selection of various cost functions are outlined, and closed-loop controller results are demonstrated for two cases: first, on an analog computer simulation of the rigid out of plane flapping dynamics of a single rotor blade, and second, on a 4 ft diameter single-bladed model helicopter rotor in the MIT 5 x 7 subsonic wind tunnel, both for various high levels of advance ratio. It is shown that modal control using the IBC concept is possible over a large range of advance ratios with only a modest amount of computational power required.

  13. Advanced Direct Liquefaction Concepts for PETC Generic Units - Phase II

    SciTech Connect

    1997-12-01

    The results of Laboratory and Bench-Scale experiments and supporting technical and economic assessments conducted under DOE Contract No. DE-AC22-91PC91040 are reported for the period July 1, 1997 to September 30, 1997. This contract is with the University of Kentucky Research Foundation which supports work with the University of Kentucky Center for Applied Energy Research, CONSOL, Inc., LDP Associates, and Hydrocarbon Technologies, Inc. This work involves the introduction into the basic two stage liquefaction process several novel concepts which include dispersed lower-cost catalysts, coal cleaning by oil agglomeration, and distillate hydrotreating and dewaxing. Results are reported from experiments in which various methods were tested to activate dispersed Mo precursors. Several oxothiomolybdates precursors having S/Mo ratios from two to six were prepared. Another having a S/Mo ratio of eleven was also prepared that contained an excess of sulfur. In the catalyst screening test, none of these precursors exhibited an activity enhancement that might suggest that adding sulfur into the structure of the Mo precursors would be beneficial to the process. In another series of experiments, AHM impregnated coal slurried in the reaction mixture was pretreated withH S/H under pressure and successively heated for 30 min at 120, 250 2 2 and 360 C. THF conversions in the catalyst screening test were not affected while resid conversions o increased such that pretreated coals impregnated with 100 ppm Mo gave conversions equivalent to untreated coals impregnated with 300 ppm fresh Mo. Cobalt, nickel and potassium phosphomolybdates were prepared and tested as bimetallic precursors. The thermal stability of these compounds was evaluated in TG/MS to determine whether the presence of the added metal would stabilize the Keggin structure at reaction temperature. Coals impregnated with these salts showed the Ni and Co salts gave the same THF conversion as PMA while the Ni salt gave higher

  14. Concept of advanced spent fuel reprocessing based on ion exchange

    SciTech Connect

    Suzuki, Tatsuya; Takahashi, Kazuyuki; Nogami, Masanobu; Nomura, Masao; Fujii, Yasuhiko; Ozawa, Masaki |; Koyama, Shinichi; Mimura, Hitosi; Fujita, Reiko

    2007-07-01

    Reprocessing based on ion exchange separation is proposed as a safe, proliferation-resistant technology. Tertiary pyridine resin was developed for ion exchange reprocessing. Working medium of the separation system is not nitric acid but hydrochloric acid aqueous solution. The system does not involve strong oxidizing reagent, such as nitric acid but involve chloride ions which works as the week neutron absorbers. The system can be operated at ambient temperatures and pressure. Thus the HCl-ion-exchange reprocessing is regarded as an inherently safe technology. Another advantage of HCl ion-exchange reprocessing is the proliferation-resistant nature. Both U(VI) and Pu(IV) ions are adsorbed in the pyridine type anion exchange resin at relatively high HCl concentration of 6 M. At this condition, the adsorption distribution coefficient of Pu(IV) is smaller than that of U(VI). When uranium is eluted from the resin in the column, plutonium is simultaneously eluted from the column; Pu is recovered with uranium in the front part of uranium adsorption band. Pu(IV) can not be left in the resin after elution of uranium. The use of HCl in the ion-exchange reprocessing causes the problem of the plant materials. Sophisticated material technology is necessary to realize the ion exchange reprocessing using HCl. The technology is so sophisticated that only highly developed countries can hold the technology, thus the technology holding countries will be limited. The plant, therefore, cannot be built under hidden state. In addition, another merit of the process would be the simplicity in operation. One phase, i.e., ion exchange resin is immobile, and the aqueous solution is the only mobile phase. Plant operation is made by the control of one aqueous solution phase. The plant simplicity would ease the international safeguard inspection efforts to be applicable to this kind of reprocessing plant. The present work shows the basic concept of ion exchange reprocessing using HCl medium

  15. Development and testing of advanced cryogenic thermal switch concepts

    NASA Astrophysics Data System (ADS)

    Marland, B.; Bugby, D.; Stouffer, C.

    2000-01-01

    This paper describes the development and testing of two advanced cryogenic thermal switch (CTSW) options for use in long-life cryogenic space systems. The principal application for these two CTSW options in such systems is in implementing cryocooler redundancy with a minimum parasitic heating penalty. The two CTSW configurations covered in the paper are a hydrogen gas-gap (H2-GG) design, flown on STS-95 in October 1998 as part of the CRYOTSU Hitchhiker flight experiment, and a differential thermal expansion (DTE) design. Both options are constructed primarily of beryllium for CTE compatibility with beryllium cryogenic components. The H2-GG design utilizes a flat 2-mil gap between two cylindrical beryllium halves that are supported by a thin-walled titanium tube. A highly convoluted stainless steel bellows seals the unit. The H2-GG CTSW is nominally ``off'' (evacuated) until actuated ``on'' by heating a metal hydride getter, which evolves hydrogen and provides thermal conductance across the gap. The H2-GG design has demonstrated an ``on'' conductance of 1.0 W/K, an ``off'' resistance of 1000-1500 K/W and a range of operation from 15K-300K. The DTE design, which has just three parts, is very similar to the H2-GG design except that a stainless steel tube replaces the titanium tube and the bellows and getter are no longer needed. The DTE CSTW is actuated ``on'' (both sides cold) by the higher CTE of stainless steel compared to beryllium and actuated ``off'' by temporarily applying power to a small heater on the stainless steel tube to expand the tube enough to open the gap. After the smaller of the two beryllium parts warms sufficiently, the heater is no longer needed and the DTE CTSW remains ``off'' (one side cold, one side warm). The DTE design has demonstrated the potential for an ``on'' conductance greater than 1.0 W/K, an ``off'' resistance of 1400 K/W and a range of operation from less than 4K to 300K. This paper describes the design of each CTSW option and the

  16. Advanced materials and concepts for energy storage devices

    NASA Astrophysics Data System (ADS)

    Teng, Shiang Jen

    Over the last decade, technological progress and advances in the miniaturization of electronic devices have increased demands for light-weight, high-efficiency, and carbon-free energy storage devices. These energy storage devices are expected to play important roles in automobiles, the military, power plants, and consumer electronics. Two main types of electrical energy storage systems studied in this research are Li ion batteries and supercapacitors. Several promising solid state electrolytes and supercapacitor electrode materials are investigated in this research. The first section of this dissertation is focused on the novel results on pulsed laser annealing of Li7La3Zr2O12 (LLZO). LLZO powders with a tetragonal structure were prepared by a sol-gel technique, then a pulsed laser annealing process was employed to convert the tetragonal powders to cubic LLZO without any loss of lithium. The second section of the dissertation reports on how Li5La 3Nb2O12 (LLNO) was successfully synthesized via a novel molten salt synthesis (MSS) method at the relatively low temperature of 900°C. The low sintering temperature prevented the loss of lithium that commonly occurs during synthesis using conventional solid state or wet chemical reactions. The second type of energy storage device studied is supercapacitors. Currently, research on supercapacitors is focused on increasing their energy densities and lowering their overall production costs by finding suitable electrode materials. The third section of this dissertation details how carbonized woods electrodes were used as supercapacitor electrode materials. A high energy density of 45.6 Wh/kg and a high power density of 2000 W/kg were obtained from the supercapacitor made from carbonized wood electrodes. The high performance of the supercapacitor was discovered to originate from the hierarchical porous structures of the carbonized wood. Finally, the fourth section of this dissertation is on the electrochemical effects of

  17. ADVANCED UNDERGROUND GAS STORAGE CONCEPTS REFRIGERATED-MINED CAVERN STORAGE

    SciTech Connect

    1998-09-01

    Limited demand and high cost has prevented the construction of hard rock caverns in this country for a number of years. The storage of natural gas in mined caverns may prove technically feasible if the geology of the targeted market area is suitable; and economically feasible if the cost and convenience of service is competitive with alternative available storage methods for peak supply requirements. It is believed that mined cavern storage can provide the advantages of high delivery rates and multiple fill-withdrawal cycles in areas where salt cavern storage is not possible. In this research project, PB-KBB merged advanced mining technologies and gas refrigeration techniques to develop conceptual designs and cost estimates to demonstrate the commercialization potential of the storage of refrigerated natural gas in hard rock caverns. Five regions of the U.S.A. were studied for underground storage development and PB-KBB reviewed the literature to determine if the geology of these regions was suitable for siting hard rock storage caverns. Area gas market conditions in these regions were also studied to determine the need for such storage. Based on an analysis of many factors, a possible site was determined to be in Howard and Montgomery Counties, Maryland. The area has compatible geology and a gas industry infrastructure for the nearby market populous of Baltimore and Washington D.C.. As Gas temperature is lowered, the compressibility of the gas reaches an optimum value. The compressibility of the gas, and the resultant gas density, is a function of temperature and pressure. This relationship can be used to commercial advantage by reducing the size of a storage cavern for a given working volume of natural gas. This study looks at this relationship and and the potential for commercialization of the process in a storage application. A conceptual process design, and cavern design were developed for various operating conditions. Potential site locations were considered

  18. Earth's Critical Zone and hydropedology: concepts, characteristics, and advances

    NASA Astrophysics Data System (ADS)

    Lin, H. S.

    2009-04-01

    The Critical Zone (CZ) is a holistic framework for integrated studies of water with soil, rock, air, and biotic resources in terrestrial environments. This is consistent with the recognition of water as a unifying theme for research on complex environmental systems. The CZ ranges from the top of the vegetation down to the bottom of the aquifer, with a highly variable thickness (from <0.001 to >10 km). The pedosphere is the foundation of the CZ, which represents a geomembrance across which water and solutes, as well as energy, gases, solids, and organisms are actively exchanged with the atmosphere, biosphere, hydrosphere, and lithosphere to create a life-sustaining environment. Hydropedology - the science of the behaviour and distribution of soil-water interactions in contact with mineral and biological materials in the CZ - is an important contributor to CZ research. This article reviews and discusses the basic ideas and fundamental features of the CZ and hydropedology, and suggests ways for their advances. An "outward" growth model, instead of an "inward" contraction, is suggested for propelling soil science forward. The CZ is the right platform for synergistic collaborations across disciplines. The reconciliation of the geological (or "big") cycle and the biological (or "small") cycle that are orders of magnitude different in space and time is a key to understanding and predicting complex CZ processes. Because of the layered nature of the CZ and the general trend of increasing density with depth, response and feedback to climate change take longer from the above-ground zone down to the soil zone and further to the groundwater zone. Interfaces between layers and cycles are critical controls of the landscape-soil-water-ecosystem dynamics, which present fertile grounds for interdisciplinary research. Ubiquitous heterogeneity in the CZ can be addressed by environmental gradients and landscape patterns, where hierarchical structures control the landscape complex of

  19. Novel Compressor Blade Design Study

    NASA Astrophysics Data System (ADS)

    Srinivas, Abhay

    Jet engine efficiency goals are driving compressors to higher pressure ratios and engines to higher bypass ratios, each one driving to smaller cores. This is leading to larger tip gaps relative to the blade height. These larger relative tip clearances would negate some of the cycle improvements, and ways to mitigate this effect must be found. A novel split tip blade geometry has been created which helps improve the efficiency at large clearances while also improving operating range. Two identical blades are leaned in opposite directions starting at 85% span. They are cut at mid chord and the 2 halves then merged together so a split tip is created. The result is similar to the alula feathers on a soaring bird. The concept is that the split tip will energize the tip flow and increase range. For higher relative tip clearance, this will also improve efficiency. The 6th rotor of a highly loaded 10 stage machine was chosen as the baseline for this study. Three dimensional CFD simulations were performed using CD Adapco's Star-CCM+ at 5 clearances for the baseline and split tip geometry. The choking flow and stall margin of the split tip blade was higher than that of the baseline blade for all tip clearances. The pressure ratio of the novel blade was higher than that of the baseline blade near choke, but closer to stall it decreased. The sensitivity of peak efficiency to clearance was improved. At tight clearances of 0.62% of blade height, the maximum efficiency of the new design was less than the baseline blade, but as the tip clearance was increased above 2.5%, the maximum efficiency increased. Structural analysis was also performed to ascertain the feasibility of the design.

  20. Proceedings of the Workshop on Advanced Network and Technology Concepts for Mobile, Micro, and Personal Communications

    NASA Technical Reports Server (NTRS)

    Paul, Lori (Editor)

    1991-01-01

    The Workshop on Advanced Network and Technology Concepts for Mobile, Micro, and Personal Communications was held at NASA's JPL Laboratory on 30-31 May 1991. It provided a forum for reviewing the development of advanced network and technology concepts for turn-of-the-century telecommunications. The workshop was organized into three main categories: (1) Satellite-Based Networks (L-band, C-band, Ku-band, and Ka-band); (2) Terrestrial-Based Networks (cellular, CT2, PCN, GSM, and other networks); and (3) Hybrid Satellite/Terrestrial Networks. The proceedings contain presentation papers from each of the above categories.

  1. An advanced bioprocessing concept for the conversion of wastepaper to ethanol

    SciTech Connect

    Scott, C.D.; Davison, B.H.; Scott, T.C.; Woodward, J.; Dees, C.; Rothrock, D.S.

    1993-06-01

    Wastepaper is a plentiful and low-cost lignocellulosic feed material that may represent the most direct way to penetrate the market with an advanced bioprocessing system. Innovative bioprocessing concepts integrated into such a system for the production of ethanol should be economically viable. Several of the proposed processing advances for such a system have only been studied on a laboratory scale, so a more thorough process development and scale-up effort will be required.

  2. Blade for turbine engine

    NASA Technical Reports Server (NTRS)

    Suciu, Gabriel L. (Inventor); Babu, Michael (Inventor); Murdock, James R. (Inventor)

    2004-01-01

    A blade for a turbine engine having a centerline. The blade comprises: a root section extending at an angle relative to the centerline; and an airfoil section extending from the root section. The root section is directly adjacent said airfoil section. In other words, the blade is neckless. The blade is part of a rotor assembly, and is preferably a fan blade.

  3. Definition of a 5MW/61.5m wind turbine blade reference model.

    SciTech Connect

    Resor, Brian Ray

    2013-04-01

    A basic structural concept of the blade design that is associated with the frequently utilized %E2%80%9CNREL offshore 5-MW baseline wind turbine%E2%80%9D is needed for studies involving blade structural design and blade structural design tools. The blade structural design documented in this report represents a concept that meets basic design criteria set forth by IEC standards for the onshore turbine. The design documented in this report is not a fully vetted blade design which is ready for manufacture. The intent of the structural concept described by this report is to provide a good starting point for more detailed and targeted investigations such as blade design optimization, blade design tool verification, blade materials and structures investigations, and blade design standards evaluation. This report documents the information used to create the current model as well as the analyses used to verify that the blade structural performance meets reasonable blade design criteria.

  4. Development of a metal-clad advanced composite shear web design concept

    NASA Technical Reports Server (NTRS)

    Laakso, J. H.

    1974-01-01

    An advanced composite web concept was developed for potential application to the Space Shuttle Orbiter main engine thrust structure. The program consisted of design synthesis, analysis, detail design, element testing, and large scale component testing. A concept was sought that offered significant weight saving by the use of Boron/Epoxy (B/E) reinforced titanium plate structure. The desired concept was one that was practical and that utilized metal to efficiently improve structural reliability. The resulting development of a unique titanium-clad B/E shear web design concept is described. Three large scale components were fabricated and tested to demonstrate the performance of the concept: a titanium-clad plus or minus 45 deg B/E web laminate stiffened with vertical B/E reinforced aluminum stiffeners.

  5. NOVEL CONCEPTS, METHODS AND ADVANCED TECHNOLOGY IN PARTICULATE/GAS SEPARATION

    EPA Science Inventory

    This paper discusses presentations made during a symposium on novel concepts, methods, and advanced technology in particulate/gas separation. The symposium, held at the University of Notre Dame and sponsored by the National Science Foundation and the Environmental Protection Agen...

  6. An Exploration of Learners' Conceptions of Language, Culture, and Learning in Advanced-Level Spanish Courses

    ERIC Educational Resources Information Center

    Drewelow, Isabelle; Mitchell, Claire

    2015-01-01

    This article reports on an exploratory study, which examines learners' rating of culture in relation to other concepts in advanced Spanish courses and their justification of the ratings attributed. Open-ended responses, elicited from a questionnaire completed by 179 respondents, were analysed line by line using an interpretive approach. Data…

  7. The Effect of Background Experience and an Advance Organizer on the Attainment of Certain Science Concepts.

    ERIC Educational Resources Information Center

    McAdaragh, Mary Kathleen

    This study examined the effects of an advance organizer and background experience in science on the attainment of science concepts. Ninth-grade earth science students (N=90) were given the Dubbins Earth Science Test (DEST) and a Science Background Experience Inventory (SBEI) developed by the author. They were then placed into high, medium, and low…

  8. Recognizing and Managing Complexity: Teaching Advanced Programming Concepts and Techniques Using the Zebra Puzzle

    ERIC Educational Resources Information Center

    Crabtree, John; Zhang, Xihui

    2015-01-01

    Teaching advanced programming can be a challenge, especially when the students are pursuing different majors with diverse analytical and problem-solving capabilities. The purpose of this paper is to explore the efficacy of using a particular problem as a vehicle for imparting a broad set of programming concepts and problem-solving techniques. We…

  9. LOW NOX COMBUSTION CONCEPTS FOR ADVANCED POWER GENERATION SYSTEMS FIRING LOW-BTU GAS

    EPA Science Inventory

    The report gives results of an analysis of several advanced power generating concepts firing low-Btu gasified coal. A combined gas-turbine/steam-cycle power plant with integrated gasifier was the most promising from fuel utilization and economic viewpoints. Two representative com...

  10. Teaching Advanced Concepts in Computer Networks: VNUML-UM Virtualization Tool

    ERIC Educational Resources Information Center

    Ruiz-Martinez, A.; Pereniguez-Garcia, F.; Marin-Lopez, R.; Ruiz-Martinez, P. M.; Skarmeta-Gomez, A. F.

    2013-01-01

    In the teaching of computer networks the main problem that arises is the high price and limited number of network devices the students can work with in the laboratories. Nowadays, with virtualization we can overcome this limitation. In this paper, we present a methodology that allows students to learn advanced computer network concepts through…

  11. Advanced Monobore Concept, Development of CFEX Self-Expanding Tubular Technology

    SciTech Connect

    Jeff Spray

    2007-09-30

    The Advanced Monobore Concept--CFEX{copyright} Self-Expanding Tubular Technology Development was a successfully executed fundamental research through field demonstration project. This final report is presented as a progression, according to basic technology development steps. For this project, the research and development steps used were: concept development, engineering analysis, manufacturing, testing, demonstration, and technology transfer. The CFEX{copyright} Technology Development--Advanced Monobore Concept Project successfully completed all of the steps for technology development, covering fundamental research, conceptual development, engineering design, advanced-level prototype construction, mechanical testing, and downhole demonstration. Within an approximately two year period, a partially defined, broad concept was evolved into a substantial new technological area for drilling and production engineering applicable a variety of extractive industries--which was also successfully demonstrated in a test well. The demonstration achievement included an actual mono-diameter placement of two self-expanding tubulars. The fundamental result is that an economical and technically proficient means of casing any size of drilling or production well or borehole is indicated as feasible based on the results of the project. Highlighted major accomplishments during the project's Concept, Engineering, Manufacturing, Demonstration, and Technology Transfer phases, are given.

  12. Impact resistance of composite fan blades

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Results are presented of a program to determine the impact resistance of composite fan blades subjected to foreign object damage (FOD) while operating under conditions simulating a short take-off and landing (STOL) engine at takeoff. The full-scale TF39 first-stage fan blade was chosen as the base design for the demonstration component since its configuration and operating tip speeds are similar to a typical STOL fan blade several composite configurations had already been designed and evaluated under previous programs. The first portion of the program was devoted toward fabricating and testing high impact resistant, aerodynamically acceptable composite blades which utilized only a single material system in any given blade. In order to increase the blade impact capability beyond this point, several mixed material (hybrid) designs were investigated using S-glass and Kevlar as well as boron and graphite fibers. These hybrid composite blades showed a marked improvement in resistance to bird impact over those blades made of a single composite material. The work conducted under this program has demonstrated substantial improvement in composite fan blades with respect to FOD resistance and has indicated that the hybrid design concept, which utilizes different types of fibers in various portions of a fan blade design depending on the particular requirements of the different areas and the characteristics of the different fibers involved, shows a significant improvement over those designs utilizing only one material system.

  13. Investigation of Advanced Counterrotation Blade Configuration Concepts for High Speed Turboprop Systems. Task 8: Cooling Flow/heat Transfer Analysis

    NASA Technical Reports Server (NTRS)

    Hall, Edward J.; Topp, David A.; Heidegger, Nathan J.; Delaney, Robert A.

    1994-01-01

    The focus of this task was to validate the ADPAC code for heat transfer calculations. To accomplish this goal, the ADPAC code was modified to allow for a Cartesian coordinate system capability and to add boundary conditions to handle spanwise periodicity and transpiration boundaries. The primary validation case was the film cooled C3X vane. The cooling hole modeling included both a porous region and grid in each discrete hold. Predictions for these models as well as smooth wall compared well with the experimental data.

  14. Investigation of advanced counterrotation blade configuration concepts for high speed turboprop systems, task 1: Ducted propfan analysis

    NASA Technical Reports Server (NTRS)

    Hall, Edward J.; Delaney, Robert A.; Bettner, James L.

    1990-01-01

    The time-dependent three-dimensional Euler equations of gas dynamics were solved numerically to study the steady compressible transonic flow about ducted propfan propulsion systems. Aerodynamic calculations were based on a four-stage Runge-Kutta time-marching finite volume solution technique with added numerical dissipation. An implicit residual smoothing operator was used to aid convergence. Two calculation grids were employed in this study. The first grid utilized an H-type mesh network with a branch cut opening to represent the axisymmetric cowl. The second grid utilized a multiple-block mesh system with a C-type grid about the cowl. The individual blocks were numerically coupled in the Euler solver. Grid systems were generated by a combined algebraic/elliptic algortihm developed specifically for ducted propfans. Numerical calculations were initially performed for unducted propfans to verify the accuracy of the three-dimensional Euler formulation. The Euler analyses were then applied for the calculation of ducted propfan flows, and predicted results were compared with experimental data for two cases. The three-dimensional Euler analyses displayed exceptional accuracy, although certain parameters were observed to be very sensitive to geometric deflections. Both solution schemes were found to be very robust and demonstrated nearly equal efficiency and accuracy, although it was observed that the multi-block C-grid formulation provided somewhat better resolution of the cowl leading edge region.

  15. Ceramic blade attachment system

    DOEpatents

    Boyd, G.L.

    1995-04-11

    A retainer ring is arranged to mount turbine blades to a turbine disk so that aerodynamic forces produced by a gas turbine engine are transferred from the turbine blades to the turbine disk to cause the turbine blades and turbine disk to rotate, but so that centrifugal forces of the turbine blades resulting from the rotation of the turbine blades and turbine disk are not transferred from the turbine blades to the turbine disk. 6 figures.

  16. Ceramic blade attachment system

    DOEpatents

    Boyd, Gary L.

    1995-01-01

    A retainer ring is arranged to mount turbine blades to a turbine disk so that aerodynamic forces produced by a gas turbine engine are transferred from the turbine blades to the turbine disk to cause the turbine blades and turbine disk to rotate, but so that centrifugal forces of the turbine blades resulting from the rotation of the turbine blades and turbine disk are not transferred from the turbine blades to the turbine disk.

  17. Fiber composite fan blade impact improvement

    NASA Technical Reports Server (NTRS)

    Graff, J.; Stoltze, L.; Varholak, E. M.

    1976-01-01

    The improved foreign object damage resistance of a metal matrix advanced composite fan blade was demonstrated. The fabrication, whirl impact test and subsequent evaluation of nine advanced composite fan blades of the "QCSEE" type design were performed. The blades were designed to operate at a tip speed of 282 m/sec. The blade design was the spar/shell type, consisting of a titanium spar and boron/aluminum composite airfoils. The blade retention was designed to rock on impact with large birds, thereby reducing the blade bending stresses. The program demonstrated the ability of the blades to sustain impacts with up to 681 g slices of birds at 0.38 rad with little damage (only 1.4 percent max weight loss) and 788 g slices of birds at 0.56 rad with only 3.2 percent max weight loss. Unbonding did not exceed 1.1 percent of the post-test blade area during any of the tests. All blades in the post-test condition were judged capable of operation in accordance with the FAA guidelines for medium and large bird impacts.

  18. Cyclic Structural Analyses of SSME Turbine Blades

    NASA Technical Reports Server (NTRS)

    Kaufman, A.; Manderscheid, J. M.

    1985-01-01

    The problems of calculating the structural response of high-temperature space propulsion components such as turbine blades for the fuel turbopump are addressed. The first high-pressure-stage fuel turbine blade (HPFTB) in the liquid-hydrogen turbopump of the space shuttle main engine (SSME) was selected for this study. In the past these blades have cracked in the blade shank region and at the airfoil leading edge adjacent to the platform. To achieve the necessary durability, these blades are currently being cast by using directional solidification. Single-crystal alloys are also being investigated for future SSME applications. The study evaluated the utility of advanced structural analysis methods in assessing the low-cycle fatigue lives of these anisotropic components. The turbine blade airfoil of the high-pressure stage of the SSME fuel turbopump was analyzed because it has a history of rapid crack initiation.

  19. Blade Vibration Measurement System

    NASA Technical Reports Server (NTRS)

    Platt, Michael J.

    2014-01-01

    The Phase I project successfully demonstrated that an advanced noncontacting stress measurement system (NSMS) could improve classification of blade vibration response in terms of mistuning and closely spaced modes. The Phase II work confirmed the microwave sensor design process, modified the sensor so it is compatible as an upgrade to existing NSMS, and improved and finalized the NSMS software. The result will be stand-alone radar/tip timing radar signal conditioning for current conventional NSMS users (as an upgrade) and new users. The hybrid system will use frequency data and relative mode vibration levels from the radar sensor to provide substantially superior capabilities over current blade-vibration measurement technology. This frequency data, coupled with a reduced number of tip timing probes, will result in a system capable of detecting complex blade vibrations that would confound traditional NSMS systems. The hardware and software package was validated on a compressor rig at Mechanical Solutions, Inc. (MSI). Finally, the hybrid radar/tip timing NSMS software package and associated sensor hardware will be installed for use in the NASA Glenn spin pit test facility.

  20. Advanced Spacesuit Portable Life Support System Packaging Concept Mock-Up Design & Development

    NASA Technical Reports Server (NTRS)

    O''Connell, Mary K.; Slade, Howard G.; Stinson, Richard G.

    1998-01-01

    A concentrated development effort was begun at NASA Johnson Space Center to create an advanced Portable Life Support System (PLSS) packaging concept. Ease of maintenance, technological flexibility, low weight, and minimal volume are targeted in the design of future micro-gravity and planetary PLSS configurations. Three main design concepts emerged from conceptual design techniques and were carried forth into detailed design, then full scale mock-up creation. "Foam", "Motherboard", and "LEGOtm" packaging design concepts are described in detail. Results of the evaluation process targeted maintenance, robustness, mass properties, and flexibility as key aspects to a new PLSS packaging configuration. The various design tools used to evolve concepts into high fidelity mock ups revealed that no single tool was all encompassing, several combinations were complimentary, the devil is in the details, and, despite efforts, many lessons were learned only after working with hardware.

  1. Learning Through Doing: Teaching Advanced Physics Concepts Through Freshmen Research Immersion

    NASA Astrophysics Data System (ADS)

    Wahila, Matthew; Piper, Louis; Amey, Jennifer; Jones, Wayne; Fegley, Megan; Stamp, Nancy

    Often undergraduates have difficulty grasping advanced concepts in physics due to the seemingly abstract and foreign nature of the time and length scales involved. The ``Smart Energy'' Freshmen Research Immersion (FRI) program at Binghamton University was created as a way to address this issue and, in turn, improve undergraduate performance and retention in physics and chemistry. Using real-world research problems as a wider context to frame their understanding, we have developed a course sequence providing a more intuitive and comprehensive understanding of core physics and chemistry concepts over the course of the program. Advanced condensed matter topics, such as optical band gaps, crystal and electronic structure, and electron/hole conduction are introduced to students through hands-on, authentic research activities incorporating materials for real-world device applications. I will discuss how employing p-n junctions as a model device can allow for a natural and intuitive progression from basic to advanced physics and chemistry concepts. This approach illustrates how shifting exotic concepts into a more relatable form through the use of analogy is important for fostering a more intuitive understanding of physical phenomena.

  2. Advanced Radioisotope Power System Enabled Titan Rover Concept with Inflatable Wheels

    NASA Astrophysics Data System (ADS)

    Balint, Tibor S.; Schriener, Timothy M.; Shirley, James H.

    2006-01-01

    The Decadal Survey identified Titan as one of the top priority science destinations in the large moons category, while NASA's proposed Design Reference Mission Set ranked a Titan in-situ explorer second, after a recommended Europa Geophysical Explorer mission. This paper discusses a Titan rover concept, enabled by a single advanced Radioisotope Power System that could provide about 110 We (BOL). The concept targets the smaller Flagship or potentially the New Frontiers mission class. This MSL class rover would traverse on four 1.5 m diameter inflatable wheels during its 3 years mission duration and would use as much design and flight heritage as possible to reduce mission cost. Direct to Earth communication would remove the need for a relay orbiter. Details on the strawman instrument payload, and rover subsystems are given for this science driven mission concept. In addition, power system trades between Advanced RTG, TPV, and Advanced-Stirling and Brayton RPSs are outlined. While many possible approaches exist for Titan in-situ exploration, the Titan rover concept presented here could provide a scientifically interesting and programmatically affordable solution.

  3. A Framework for Human Performance Criteria for Advanced Reactor Operational Concepts

    SciTech Connect

    Jacques V Hugo; David I Gertman; Jeffrey C Joe

    2014-08-01

    This report supports the determination of new Operational Concept models needed in support of the operational design of new reactors. The objective of this research is to establish the technical bases for human performance and human performance criteria frameworks, models, and guidance for operational concepts for advanced reactor designs. The report includes a discussion of operating principles for advanced reactors, the human performance issues and requirements for human performance based upon work domain analysis and current regulatory requirements, and a description of general human performance criteria. The major findings and key observations to date are that there is some operating experience that informs operational concepts for baseline designs for SFR and HGTRs, with the Experimental Breeder Reactor-II (EBR-II) as a best-case predecessor design. This report summarizes the theoretical and operational foundations for the development of a framework and model for human performance criteria that will influence the development of future Operational Concepts. The report also highlights issues associated with advanced reactor design and clarifies and codifies the identified aspects of technology and operating scenarios.

  4. Advanced EVA Capabilities: A Study for NASA's Revolutionary Aerospace Systems Concept Program

    NASA Technical Reports Server (NTRS)

    Hoffman, Stephen J.

    2004-01-01

    This report documents the results of a study carried out as part of NASA s Revolutionary Aerospace Systems Concepts Program examining the future technology needs of extravehicular activities (EVAs). The intent of this study is to produce a comprehensive report that identifies various design concepts for human-related advanced EVA systems necessary to achieve the goals of supporting future space exploration and development customers in free space and on planetary surfaces for space missions in the post-2020 timeframe. The design concepts studied and evaluated are not limited to anthropomorphic space suits, but include a wide range of human-enhancing EVA technologies as well as consideration of coordination and integration with advanced robotics. The goal of the study effort is to establish a baseline technology "road map" that identifies and describes an investment and technical development strategy, including recommendations that will lead to future enhanced synergistic human/robot EVA operations. The eventual use of this study effort is to focus evolving performance capabilities of various EVA system elements toward the goal of providing high performance human operational capabilities for a multitude of future space applications and destinations. The data collected for this study indicate a rich and diverse history of systems that have been developed to perform a variety of EVA tasks, indicating what is possible. However, the data gathered for this study also indicate a paucity of new concepts and technologies for advanced EVA missions - at least any that researchers are willing to discuss in this type of forum.

  5. Advanced Space Transportation Concepts and Propulsion Technologies for a New Delivery Paradigm

    NASA Technical Reports Server (NTRS)

    Robinson, John W.; McCleskey, Carey M.; Rhodes, Russel E.; Lepsch, Roger A.; Henderson, Edward M.; Joyner, Claude R., III; Levack, Daniel J. H.

    2013-01-01

    This paper describes Advanced Space Transportation Concepts and Propulsion Technologies for a New Delivery Paradigm. It builds on the work of the previous paper "Approach to an Affordable and Productive Space Transportation System". The scope includes both flight and ground system elements, and focuses on their compatibility and capability to achieve a technical solution that is operationally productive and also affordable. A clear and revolutionary approach, including advanced propulsion systems (advanced LOX rich booster engine concept having independent LOX and fuel cooling systems, thrust augmentation with LOX rich boost and fuel rich operation at altitude), improved vehicle concepts (autogeneous pressurization, turbo alternator for electric power during ascent, hot gases to purge system and keep moisture out), and ground delivery systems, was examined. Previous papers by the authors and other members of the Space Propulsion Synergy Team (SPST) focused on space flight system engineering methods, along with operationally efficient propulsion system concepts and technologies. This paper continues the previous work by exploring the propulsion technology aspects in more depth and how they may enable the vehicle designs from the previous paper. Subsequent papers will explore the vehicle design, the ground support system, and the operations aspects of the new delivery paradigm in greater detail.

  6. Unsteady Blade Row Interaction in a Transonic Turbine

    NASA Technical Reports Server (NTRS)

    Dorney, Daniel J.

    1996-01-01

    Experimental data from jet-engine tests have indicated that unsteady blade row interaction effects can have a significant impact on the performance of multiple-stage turbines. The magnitude of blade row interaction is a function of both blade-count ratio and axial spacing. In the current research program, numerical simulations have been used to quantify the effects of blade count ratio on the performance of an advanced turbine geometries.

  7. Quality Nursing Care for Hospitalized Patients with Advanced Illness: Concept Development

    PubMed Central

    Izumi, Shigeko; Baggs, Judith G.; Knafl, Kathleen A.

    2011-01-01

    The quality of nursing care as perceived by hospitalized patients with advanced illness has not been examined. A concept of quality nursing care for this population was developed by integrating the literature on constructs defining quality nursing care with empirical findings from interviews of 16 patients with advanced illness. Quality nursing care was characterized as competence and personal caring supported by professionalism and delivered with an appropriate demeanor. Although the attributes of competence, caring, professionalism, and demeanor were identified as common components of quality care across various patient populations, the caring domain increased in importance when patients with advanced illness perceived themselves as vulnerable. Assessment of quality nursing care for patients with advanced illness needs to include measures of patient perceptions of vulnerability. PMID:20572095

  8. Mission Concepts Enabled by Solar Electric Propulsion and Advanced Modular Power Systems

    NASA Astrophysics Data System (ADS)

    Klaus, Kurt K.; Elsperman, M. S.; Rogers, F.

    2013-10-01

    Introduction: Over the last several years we have introduced a number of planetary mission concepts enabled by Solar Electric Propulsion and Advanced Modular Power systems. The Boeing 702 SP: Using a common spacecraft for multiple missions reduces costs. Solar electric propulsion (SEP) provides the flexibility required for multiple mission objectives. Hosted payloads allow launch and operations costs to be shared. Advanced Modular Power System (AMPS): The 702 SP for deep space is designed to be able to use the Advanced Modular Power System (AMPS) solar array, producing multi Kw power levels with significantly lower system mass than current solar power system technologies. Mission Concepts: Outer Planets. 1) Europa Explorer - Our studies demonstrate that New Frontiers-class science missions to the Jupiter and Saturn systems are possible with commercial solar powered spacecraft. 2) Trojan Tour -The mission objective is 1143 Odysseus, consistent with the Decadal Survey REP (Radioisotope Electric Propulsion) mission objective. Small Body. 1) NEO Precursor Mission - NEO missions benefit greatly by using high ISP (Specific Impulse) Solar Electric Propulsion (SEP) coupled with high power generation systems. This concept further sets the stage for human exploration by doing the type of science exploration needed and flight demonstrating technology advances (high power generation, SEP). 2) Multiple NEO Rendezvous, Reconnaissance and In Situ Exploration - We propose a two spacecraft mission (Mother Ship and Small Body Lander) rendezvous with multiple Near Earth Objects (NEO). Mars. Our concept involved using the Boeing 702SP with a highly capable SAR imager that also conducts autonomous rendezvous and docking experiments accomplished from Mars orbit. Conclusion: Using advanced in-space power and propulsion technologies like High Power Solar Electric Propulsion provides enormous mission flexibility to execute baseline science missions and conduct Technology Demonstrations in

  9. Mission Concepts Enabled by Solar Electric Propulsion and Advanced Modular Power Systems

    NASA Astrophysics Data System (ADS)

    Elsperman, M. S.; Klaus, K.; Rogers, F.

    2013-12-01

    Introduction: Over the last several years we have introduced a number of planetary mission concepts enabled by Solar Electric Propulsion and Advanced Modular Power systems. The Boeing 702 SP: Using a common spacecraft for multiple missions reduces costs. Solar electric propulsion (SEP) provides the flexibility required for multiple mission objectives. Hosted payloads allow launch and operations costs to be shared. Advanced Modular Power System (AMPS): The 702 SP for deep space is designed to be able to use the Advanced Modular Power System (AMPS) solar array, producing multi Kw power levels with significantly lower system mass than current solar power system technologies. Mission Concepts: Outer Planets. 1) Europa Explorer - Our studies demonstrate that New Frontiers-class science missions to the Jupiter and Saturn systems are possible with commercial solar powered spacecraft. 2) Trojan Tour -The mission objective is 1143 Odysseus, consistent with the Decadal Survey REP (Radioisotope Electric Propulsion) mission objective. Small Body. 1) NEO Precursor Mission - NEO missions benefit greatly by using high ISP (Specific Impulse) Solar Electric Propulsion (SEP) coupled with high power generation systems. This concept further sets the stage for human exploration by doing the type of science exploration needed and flight demonstrating technology advances (high power generation, SEP). 2) Multiple NEO Rendezvous, Reconnaissance and In Situ Exploration - We propose a two spacecraft mission (Mother Ship and Small Body Lander) rendezvous with multiple Near Earth Objects (NEO). Mars. Our concept involved using the Boeing 702SP with a highly capable SAR imager that also conducts autonomous rendezvous and docking experiments accomplished from Mars orbit. Conclusion: Using advanced in-space power and propulsion technologies like High Power Solar Electric Propulsion provides enormous mission flexibility to execute baseline science missions and conduct Technology Demonstrations in

  10. Spring-Blade Impact Tester

    NASA Technical Reports Server (NTRS)

    Holmes, Alan M.; Champagne, James W.

    1989-01-01

    Record of energy relationships retrieved from compact, portable tester. Spring-blade impact tester developed to support evaluation of tolerance to damage of struts under consideration for use in Space Station. Approach offers potential for determining damage as function of change in relationship between applied and absorbed energies as applied energy successively increased with each impact. Impactor strikes specimen at moment of maximum kinetic energy after spring blades released from cocked position. Concept also provides potential for measuring behavior during impact, and energy relationships retrievable from oscilloscope traces of impact.

  11. Advanced crew station concepts, displays, and input/output technology for civil aircraft of the future

    NASA Technical Reports Server (NTRS)

    Hatfield, J. J.; Robertson, J. B.; Batson, V. M.

    1979-01-01

    Current efforts on a new Cockpit Avionics Research program are described. The major thrusts of the program presented include: a comparative analysis of advanced display media and development of promising selected media, development of flight display generation techniques, and identification and development of promising I/O technology. In addition, the advanced integrated display concepts described include a 'tunnel in the sky' display and a traffic situation display with associated keyboard. Finally, the Cockpit Avionics Research program is summarized, future research plans are presented, and the need for an expanded program is discussed.

  12. Advanced transportation system study: Manned launch vehicle concepts for two way transportation system payloads to LEO

    NASA Technical Reports Server (NTRS)

    Duffy, James B.

    1993-01-01

    The purpose of the Advanced Transportation System Study (ATSS) task area 1 study effort is to examine manned launch vehicle booster concepts and two-way cargo transfer and return vehicle concepts to determine which of the many proposed concepts best meets NASA's needs for two-way transportation to low earth orbit. The study identified specific configurations of the normally unmanned, expendable launch vehicles (such as the National Launch System family) necessary to fly manned payloads. These launch vehicle configurations were then analyzed to determine the integrated booster/spacecraft performance, operations, reliability, and cost characteristics for the payload delivery and return mission. Design impacts to the expendable launch vehicles which would be required to perform the manned payload delivery mission were also identified. These impacts included the implications of applying NASA's man-rating requirements, as well as any mission or payload unique impacts. The booster concepts evaluated included the National Launch System (NLS) family of expendable vehicles and several variations of the NLS reference configurations to deliver larger manned payload concepts (such as the crew logistics vehicle (CLV) proposed by NASA JSC). Advanced, clean sheet concepts such as an F-1A engine derived liquid rocket booster (LRB), the single stage to orbit rocket, and a NASP-derived aerospace plane were also included in the study effort. Existing expendable launch vehicles such as the Titan 4, Ariane 5, Energia, and Proton were also examined. Although several manned payload concepts were considered in the analyses, the reference manned payload was the NASA Langley Research Center's HL-20 version of the personnel launch system (PLS). A scaled up version of the PLS for combined crew/cargo delivery capability, the HL-42 configuration, was also included in the analyses of cargo transfer and return vehicle (CTRV) booster concepts. In addition to strictly manned payloads, two-way cargo

  13. In flight measurement of steady and unsteady blade surface pressure of a single rotation large scale advanced prop-fan installed on the PTA aircraft

    NASA Technical Reports Server (NTRS)

    Parzych, D.; Boyd, L.; Meissner, W.; Wyrostek, A.

    1991-01-01

    An experiment was performed by Hamilton Standard, Division of United Technologies Corporation, under contract by LeRC, to measure the blade surface pressure of a large scale, 8 blade model prop-fan in flight. The test bed was the Gulfstream 2 Prop-Fan Test Assessment (PTA) aircraft. The objective of the test was to measure the steady and periodic blade surface pressure resulting from three different Prop-Fan air inflow angles at various takeoff and cruise conditions. The inflow angles were obtained by varying the nacelle tilt angles, which ranged from -3 to +2 degrees. A range of power loadings, tip speeds, and altitudes were tested at each nacelle tilt angle over the flight Mach number range of 0.30 to 0.80. Unsteady blade pressure data tabulated as Fourier coefficients for the first 35 harmonics of shaft rotational frequency and the steady (non-varying) pressure component are presented.

  14. Study of advanced composite structural design concepts for an arrow wing supersonic cruise configuration, task 3

    NASA Technical Reports Server (NTRS)

    1978-01-01

    A structural design study was conducted to assess the relative merits of structural concepts using advanced composite materials for an advanced supersonic aircraft cruising at Mach 2.7. The configuration and structural arrangement developed during Task I and II of the study, was used as the baseline configuration. Allowable stresses and strains were established for boron and advanced graphite fibers based on projected fiber properties available in the next decade. Structural concepts were designed and analyzed using graphite polyimide and boron polyimide, applied to stiffened panels and conventional sandwich panels. The conventional sandwich panels were selected as the structural concept to be used on the wing structure. The upper and lower surface panels of the Task I arrow wing were redesigned using high-strength graphite polyimide sandwich panels over the titanium spars and ribs. The ATLAS computer system was used as the basis for stress analysis and resizing the surface panels using the loads from the Task II study, without adjustment for change in aeroelastic deformation. The flutter analysis indicated a decrease in the flutter speed compared to the baseline titanium wing design. The flutter analysis indicated a decrease in the flutter speed compared to the baseline titanium wing design. The flutter speed was increased to that of the titanium wing, with a weight penalty less than that of the metallic airplane.

  15. NASA Advanced Concepts Office, Earth-To-Orbit Team Design Process and Tools

    NASA Technical Reports Server (NTRS)

    Waters, Eric D.; Creech, Dennis M.; Garcia, Jessica; Threet, Grady E., Jr.; Phillips, Alan

    2012-01-01

    The Earth-to-Orbit Team (ETO) of the Advanced Concepts Office (ACO) at NASA Marshall Space Flight Center (MSFC) is considered the pre-eminent go-to group for pre-phase A and phase A concept definition. Over the past several years the ETO team has evaluated thousands of launch vehicle concept variations for a significant number of studies including agency-wide efforts such as the Exploration Systems Architecture Study (ESAS), Constellation, Heavy Lift Launch Vehicle (HLLV), Augustine Report, Heavy Lift Propulsion Technology (HLPT), Human Exploration Framework Team (HEFT), and Space Launch System (SLS). The ACO ETO Team is called upon to address many needs in NASA s design community; some of these are defining extremely large trade-spaces, evaluating advanced technology concepts which have not been addressed by a large majority of the aerospace community, and the rapid turn-around of highly time critical actions. It is the time critical actions, those often limited by schedule or little advanced warning, that have forced the five member ETO team to develop a design process robust enough to handle their current output level in order to meet their customer s needs. Based on the number of vehicle concepts evaluated over the past year this output level averages to four completed vehicle concepts per day. Each of these completed vehicle concepts includes a full mass breakdown of the vehicle to a tertiary level of subsystem components and a vehicle trajectory analysis to determine optimized payload delivery to specified orbital parameters, flight environments, and delta v capability. A structural analysis of the vehicle to determine flight loads based on the trajectory output, material properties, and geometry of the concept is also performed. Due to working in this fast-paced and sometimes rapidly changing environment, the ETO Team has developed a finely tuned process to maximize their delivery capabilities. The objective of this paper is to describe the interfaces

  16. NASA Advanced Concepts Office, Earth-To-Orbit Team Design Process and Tools

    NASA Technical Reports Server (NTRS)

    Waters, Eric D.; Garcia, Jessica; Threet, Grady E., Jr.; Phillips, Alan

    2013-01-01

    The Earth-to-Orbit Team (ETO) of the Advanced Concepts Office (ACO) at NASA Marshall Space Flight Center (MSFC) is considered the pre-eminent "go-to" group for pre-phase A and phase A concept definition. Over the past several years the ETO team has evaluated thousands of launch vehicle concept variations for a significant number of studies including agency-wide efforts such as the Exploration Systems Architecture Study (ESAS), Constellation, Heavy Lift Launch Vehicle (HLLV), Augustine Report, Heavy Lift Propulsion Technology (HLPT), Human Exploration Framework Team (HEFT), and Space Launch System (SLS). The ACO ETO Team is called upon to address many needs in NASA's design community; some of these are defining extremely large trade-spaces, evaluating advanced technology concepts which have not been addressed by a large majority of the aerospace community, and the rapid turn-around of highly time critical actions. It is the time critical actions, those often limited by schedule or little advanced warning, that have forced the five member ETO team to develop a design process robust enough to handle their current output level in order to meet their customer's needs. Based on the number of vehicle concepts evaluated over the past year this output level averages to four completed vehicle concepts per day. Each of these completed vehicle concepts includes a full mass breakdown of the vehicle to a tertiary level of subsystem components and a vehicle trajectory analysis to determine optimized payload delivery to specified orbital parameters, flight environments, and delta v capability. A structural analysis of the vehicle to determine flight loads based on the trajectory output, material properties, and geometry of the concept is also performed. Due to working in this fast-paced and sometimes rapidly changing environment, the ETO Team has developed a finely tuned process to maximize their delivery capabilities. The objective of this paper is to describe the interfaces

  17. Prestressed concrete pressure vessels and their applicability to advanced energy system concepts

    SciTech Connect

    Naus, D.J.

    1983-01-01

    Prestressed concrete pressure vessels (PCPVs) are, in essence, spaced steel structures since their strength is derived from a multitude of steel elements made up of deformed reinforcing bars and prestressing tendons which are present in sufficient quantities to carry tension loads imposed on the vessel. Other major components of a PCPV include the concrete, liner and cooling system, and insulation. PCPVs exhibit a number of advantages which make them ideally suited for application to advanced energy concepts: fabricability in virtually any size and shape using available technology, improved safety, reduced capital costs, and a history of proven performance. PCPVs have many applications to both nuclear- and non-nuclear-based energy systems concepts. Several of these concepts are discussed as well as the research and development activities conducted at ORNL in support of PCPV development.

  18. Prestressed-concrete pressure vessels and their applicability to advanced-energy-system concepts

    SciTech Connect

    Naus, D.J

    1983-01-01

    Prestressed concrete pressure vessels (PCPVs) are, in essence, spaced steel structures since their strength is derived from a multitude of steel elements made up of deformed reinforcing bars and prestressing tendons which are present in sufficient quantities to carry tension loads imposed on the vessel. Other major components of a PCPV include the concrete, liner and cooling system, and insulation. PCPVs exhibit a number of advantages which make them ideally suited for application to advanced energy concepts: fabricability in virtually any size and shape using available technology, improved safety, reduced capital costs, and a history of proven performance. PCPVs have many applications to both nuclear- and non-nuclear-based energy systems concepts. Several of these concepts will be discussed as well as the research and development activities conducted at ORNL in support of PCPV development.

  19. NASA Advanced Concepts Office, Earth-To-Orbit Team Design Process and Tools

    NASA Technical Reports Server (NTRS)

    Waters, Eric D.; Garcia, Jessica; Beers, Benjamin; Philips, Alan; Holt, James B.; Threet, Grady E., Jr.

    2013-01-01

    The Earth to Orbit (ETO) Team of the Advanced Concepts Office (ACO) at NASA Marshal Space Flight Center (MSFC) is considered the preeminent group to go to for prephase A and phase A concept definition. The ACO team has been at the forefront of a multitude of launch vehicle studies determining the future direction of the Agency as a whole due, in part, to their rapid turnaround time in analyzing concepts and their ability to cover broad trade spaces of vehicles in that limited timeframe. Each completed vehicle concept includes a full mass breakdown of each vehicle to tertiary subsystem components, along with a vehicle trajectory analysis to determine optimized payload delivery to specified orbital parameters, flight environments, and delta v capability. Additionally, a structural analysis of the vehicle based on material properties and geometries is performed as well as an analysis to determine the flight loads based on the trajectory outputs. As mentioned, the ACO Earth to Orbit Team prides themselves on their rapid turnaround time and often need to fulfill customer requests within limited schedule or little advanced notice. Due to working in this fast paced environment, the ETO team has developed some finely honed skills and methods to maximize the delivery capability to meet their customer needs. This paper will describe the interfaces between the 3 primary disciplines used in the design process; weights and sizing, trajectory, and structural analysis, as well as the approach each discipline employs to streamline their particular piece of the design process.

  20. Study of advanced electric propulsion system concept using a flywheel for electric vehicles

    NASA Technical Reports Server (NTRS)

    Younger, F. C.; Lackner, H.

    1979-01-01

    Advanced electric propulsion system concepts with flywheels for electric vehicles are evaluated and it is predicted that advanced systems can provide considerable performance improvement over existing electric propulsion systems with little or no cost penalty. Using components specifically designed for an integrated electric propulsion system avoids the compromises that frequently lead to a loss of efficiency and to inefficient utilization of space and weight. A propulsion system using a flywheel power energy storage device can provide excellent acceleration under adverse conditions of battery degradation due either to very low temperatures or high degrees of discharge. Both electrical and mechanical means of transfer of energy to and from the flywheel appear attractive; however, development work is required to establish the safe limits of speed and energy storage for advanced flywheel designs and to achieve the optimum efficiency of energy transfer. Brushless traction motor designs using either electronic commutation schemes or dc-to-ac inverters appear to provide a practical approach to a mass producible motor, with excellent efficiency and light weight. No comparisons were made with advanced system concepts which do not incorporate a flywheel.

  1. Applications of advanced V/STOL aircraft concepts to civil utility missions, volume 1

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The suitability of advanced V/STOL aircraft to civil utility applications was assessed for offshore oil support, forest fire support, transport, and humanitarian missions. The aircraft concepts considered were a lift fan aircraft, a tilt rotor aircraft, and an advanced helicopter. All the aircraft had a design payload of 2,268 kg. (5,000 lb.) with the maximum range varying from 2,224 km. (1,800 nm) for the lift fan STOL to 1,482 km (800 nm) for the advanced helicopter. The analysis of these missions considered such factors as aircraft performance, annual utilization, initial cost, and operating cost. It is concluded that all the advanced V/STOL aircraft concepts generally performed these missions better than contemporary aircraft. The lift fan aircraft and the tilt rotor aircraft were found to be effective for the offshore oil and the forest fire support missions. The lift fan aircraft in the VTOL mode was also found to be very attractive for the executive transport mission where the passenger time value was $30/hr. or more.

  2. Noise and economic characteristics of an advanced blended supersonic transport concept

    NASA Technical Reports Server (NTRS)

    Molloy, J. K.; Grantham, W. D.; Neubauer, M. J., Jr.

    1982-01-01

    Noise and economic characteristics were obtained for an advanced supersonic transport concept that utilized wing body blending, a double bypass variable cycle engine, superplastically formed and diffusion bonded titanium in both the primary and secondary structures, and an alternative interior arrangement that provides increased seating capacity. The configuration has a cruise Mach number of 2.62, provisions for 290 passengers, a mission range of 8.19 Mm (4423 n.mi.), and an average operating cruise lift drag ratio of 9.23. Advanced operating procedures, which have the potential to reduce airport community noise, were explored by using a simulator. Traded jet noise levels of 105.7 and 103.4 EPNdB were obtained by using standard and advanced takeoff operational procedures, respectively. A new method for predicting lateral attenuation was utilized in obtaining these jet noise levels.

  3. Studies of blade-vortex interaction noise reduction by rotor blade modification

    NASA Technical Reports Server (NTRS)

    Brooks, Thomas F.

    1993-01-01

    Blade-vortex interaction (BVI) noise is one of the most objectionable types of helicopter noise. This impulsive blade-slap noise can be particularly intense during low-speed landing approach and maneuvers. Over the years, a number of flight and model rotor tests have examined blade tip modification and other blade design changes to reduce this noise. Many times these tests have produced conflicting results. In the present paper, a number of these studies are reviewed in light of the current understanding of the BVI noise problem. Results from one study in particular are used to help establish the noise reduction potential and to shed light on the role of blade design. Current blade studies and some new concepts under development are also described.

  4. SMAHTR - A Concept for a Small, Modular Advanced High Temperaure Reactor

    SciTech Connect

    Gehin, Jess C; Greene, Sherrell R; Holcomb, David Eugene; Carbajo, Juan J; Cisneros, Anselmo T; Corwin, William R; Ilas, Dan; Wilson, Dane F; Varma, Venugopal Koikal; Bradley, Eric Craig; Yoder, III, Graydon L

    2010-01-01

    Several new high temperature reactor concepts, referred to as Fluoride Salt Cooled High Temperature Reactors (FHRs), have been developed over the past decade. These FHRs use a liquid salt coolant combined with high temperature gas-cooled reactor fuels (TRISO) and graphite structural materials to provide a reactor that operates at very high temperatures and is scalable to large sizes perhaps exceeding 2400 MWt. This paper presents a new small FHR the Small Modular Advanced High Temperature Reactor or SmAHTR . SmAHTR is targeted at applications that require compact, high temperature heat sources either for high efficiency electricity production or process heat applications. A preliminary SmAHTR concept has been developed that delivers 125 MWt of energy in an integral primary system design that places all primary and decay heat removal heat exchangers inside the reactor vessel. The current reactor baseline concept utilizes a prismatic fuel block core, but multiple removable fuel assembly concepts are under evaluation as well. The reactor vessel size is such that it can be transported on a standard tractor-trailer to support simplified deployment. This paper will provide a summary of the current SmAHTR system concept and on-going technology and system architecture trades studies.

  5. Evaluation of Four Advanced Nozzle Concepts for Short Takeoff and Landing Performance

    NASA Technical Reports Server (NTRS)

    Quinto, P. Frank; Kemmerly, Guy T.; Paulson, John W., Jr.

    1993-01-01

    Four advanced nozzle concepts were tested on a canard-wing fighter in the Langley 14- by 22-Foot Subsonic Tunnel. The four vectoring-nozzle concepts were as follows: (1) an axisymmetric nozzle (AXI); (2) an asymmetric, load balanced exhaust nozzle (ALBEN); (3) a low aspect ratio, single expansion ramp nozzle (LASERN); and (4) a high aspect ratio, single expansion ramp nozzle (HASERN). The investigation was conducted to determine the most suitable nozzle concept for short takeoff and landing (STOL) performance. The criterion for the best STOL performance was a takeoff ground roll of less than 1000 ft. At approach, the criteria were high lift and sufficient drag to maintain a glide slope of -3 to -6 deg with enough pitching-moment control from the canards. The test was performed at a dynamic pressure of 45 lb/sq ft and an angle-of-attack range of 0 to 20 deg. The nozzle pressure ratio was varied from 1.0 to 4.3 at both dry power and after burning nozzle configurations with nozzle vectoring to 60 deg. In addition, the model was tested in and out of ground effects. The ALBEN concept was the best of the four nozzle concepts tested for STOL performance.

  6. BLADED IMPELLER FOR TURBOBLOWERS

    DOEpatents

    Baumann, K.

    1949-10-01

    A means is given of holding open-sided impeller blades in a turbo-rotor. Two half blades, with dovetail roots of sufficient weight to contain the center of gravity, are fitted into slots cut in the rotor so as to form the desired angle between the blade faces. The adjoining edges of the half blades are welded to form one solid blade that is securely locked an the rotor. This design permits the manufacture of a V shaped impeller blade without the need of machining the entire V shaped contour from a single blank, and furthermore provides excellent locking characteristics for attachment to the rotor.

  7. US long distance fiber optic networks: Technology, evolution and advanced concepts. Volume 3: Advanced networks and economics

    NASA Technical Reports Server (NTRS)

    1986-01-01

    This study projects until 2000 the evolution of long distance fiber optic networks in the U.S. Volume 1 is the executive Summary. Volume 2 focuses on fiber optic components and systems that are directly related to the operation of long-haul networks. Optimistic, pessimistic and most likely scenarios of technology development are presented. The activities of national and regional companies implementing fiber long haul networks are also highlighted, along with an analysis of the market and regulatory forces affecting network evolution. Volume 3 presents advanced fiber optic network concept definitions. Inter-LATA traffic is quantified and forms the basis for the construction of 11-, 15-, 17-, and 23-node networks. Using the technology projections from Volume 2, a financial model identifies cost drivers and determines circuit mile costs between any two LATAs. A comparison of fiber optics with alternative transmission concludes the report.

  8. Mach number scaling of helicopter rotor blade/vortex interaction noise

    NASA Technical Reports Server (NTRS)

    Leighton, Kenneth P.; Harris, Wesley L.

    1985-01-01

    A parametric study of model helicopter rotor blade slap due to blade vortex interaction (BVI) was conducted in a 5 by 7.5-foot anechoic wind tunnel using model helicopter rotors with two, three, and four blades. The results were compared with a previously developed Mach number scaling theory. Three- and four-bladed rotor configurations were found to show very good agreement with the Mach number to the sixth power law for all conditions tested. A reduction of conditions for which BVI blade slap is detected was observed for three-bladed rotors when compared to the two-bladed baseline. The advance ratio boundaries of the four-bladed rotor exhibited an angular dependence not present for the two-bladed configuration. The upper limits for the advance ratio boundaries of the four-bladed rotors increased with increasing rotational speed.

  9. Aluminum-blade development for the Mod-0A 200-kilowatt wind turbine

    SciTech Connect

    Linscott, B.S.; Shaltens, R.K.; Eggers, A.G.

    1981-12-01

    This report documents the operating experience with two aluminum blades used on the DOE/NASA Mod-0A 200-kilowatt wind turbine located at Clayton, New Mexico. Each Mod-0A aluminum blade is 59.9 feet long and weighs 2360 pounds. The aluminum Mod-0A blade design requirements, the selected design, fabrication procedures, and the blade analyses are discussed. A detailed chronology is presented on the operating experience of the Mod-0A aluminum blades used at Clayton, New Mexico. Blade structural damage was experienced. Inspection and damage assessment were required. Structural modifications that were incorporated to the blades successfully extended the useful operating life of the blades. The aluminum blades completed the planned 2 years of operation of the Clayton wind turbine. The blades were removed from service in August 1980 to allow testing of advanced technology wood composite blades.

  10. Massachusetts Large Blade Test Facility Final Report

    SciTech Connect

    Rahul Yarala; Rob Priore

    2011-09-02

    Project Objective: The Massachusetts Clean Energy Center (CEC) will design, construct, and ultimately have responsibility for the operation of the Large Wind Turbine Blade Test Facility, which is an advanced blade testing facility capable of testing wind turbine blades up to at least 90 meters in length on three test stands. Background: Wind turbine blade testing is required to meet international design standards, and is a critical factor in maintaining high levels of reliability and mitigating the technical and financial risk of deploying massproduced wind turbine models. Testing is also needed to identify specific blade design issues that may contribute to reduced wind turbine reliability and performance. Testing is also required to optimize aerodynamics, structural performance, encourage new technologies and materials development making wind even more competitive. The objective of this project is to accelerate the design and construction of a large wind blade testing facility capable of testing blades with minimum queue times at a reasonable cost. This testing facility will encourage and provide the opportunity for the U.S wind industry to conduct more rigorous testing of blades to improve wind turbine reliability.

  11. Investigation of trailing-edge-flap, spanwise-blowing concepts on an advanced fighter configuration

    NASA Technical Reports Server (NTRS)

    Paulson, J. W., Jr.; Quinto, P. F.; Banks, D. W.

    1984-01-01

    The aerodynamic effects of spanwise blowing on the trailing edge flap of an advanced fighter aircraft configuration were determined in the 4 by 7 Meter Tunnel. A series of tests were conducted with variations in spanwise-blowing vector angle, nozzle exit area, nozzle location, thrust coefficient, and flap deflection in order to determine a superior configuration for both an underwing cascade concept and an overwing port concept. This screening phase of the testing was conducted at a nominal approach angle of attack from 12 deg to 16 deg; and then the superior configurations were tested over a more complete angle of attack range from 0 deg to 20 deg at tunnel free stream dynamic pressures from 20 to 40 lbf/sq ft at thrust coefficients from 0 to 2.

  12. Work Domain Analysis Methodology for Development of Operational Concepts for Advanced Reactors

    SciTech Connect

    Hugo, Jacques

    2015-05-01

    This report describes a methodology to conduct a Work Domain Analysis in preparation for the development of operational concepts for new plants. This method has been adapted from the classical method described in the literature in order to better deal with the uncertainty and incomplete information typical of first-of-a-kind designs. The report outlines the strategy for undertaking a Work Domain Analysis of a new nuclear power plant and the methods to be used in the development of the various phases of the analysis. Basic principles are described to the extent necessary to explain why and how the classical method was adapted to make it suitable as a tool for the preparation of operational concepts for a new nuclear power plant. Practical examples are provided of the systematic application of the method and the various presentation formats in the operational analysis of advanced reactors.

  13. Study of advanced composite structural design concepts for an arrow wing supersonic cruise configuration

    NASA Technical Reports Server (NTRS)

    Turner, M. J.; Grande, D. L.

    1978-01-01

    Based on estimated graphite and boron fiber properties, allowable stresses and strains were established for advanced composite materials. Stiffened panel and conventional sandwich panel concepts were designed and analyzed, using graphite/polyimide and boron/polyimide materials. The conventional sandwich panel was elected as the structural concept for the modified wing structure. Upper and lower surface panels of the arrow wing structure were then redesigned, using high strength graphite/polyimide sandwich panels, retaining the titanium spars and ribs from the prior study. The ATLAS integrated analysis and design system was used for stress analysis and automated resizing of surface panels. Flutter analysis of the hybrid structure showed a significant decrease in flutter speed relative to the titanium wing design. The flutter speed was increased to that of the titanium design by selective increase in laminate thickness and by using graphite fibers with properties intermediate between high strength and high modulus values.

  14. Advanced leading edge thermal-structure concept. Direct bond reusable surface insulation to a composite structure

    NASA Technical Reports Server (NTRS)

    Riccitiello, S. R.; Figueroa, H.; Coe, C. F.; Kuo, C. P.

    1984-01-01

    An advanced leading-edge concept was analyzed using the space shuttle leading edge system as a reference model. The comparison indicates that a direct-bond system utilizing a high temperature (2700 F) fibrous refractory composite insulation tile bonded to a high temperature (PI/graphite) composite structure can result in a weight savings of up to 800 lb. The concern that tile damage or loss during ascent would result in adverse entry aerodynamics if a leading edge tile system were used is addressed. It was found from experiment that missing tiles (as many as 22) on the leading edge would not significantly affect the basic force-and-moment aerodynamic coefficients. Additionally, this concept affords a degree of redundancy to a thermal protection system in that the base structure (being a composite material) ablates and neither melts nor burns through when subjected to entry heating in the event tiles are actually lost or damaged during ascent.

  15. Optimization of an Advanced Hybrid Wing Body Concept Using HCDstruct Version 1.2

    NASA Technical Reports Server (NTRS)

    Quinlan, Jesse R.; Gern, Frank H.

    2016-01-01

    Hybrid Wing Body (HWB) aircraft concepts continue to be promising candidates for achieving the simultaneous fuel consumption and noise reduction goals set forth by NASA's Environmentally Responsible Aviation (ERA) project. In order to evaluate the projected benefits, improvements in structural analysis at the conceptual design level were necessary; thus, NASA researchers developed the Hybrid wing body Conceptual Design and structural optimization (HCDstruct) tool to perform aeroservoelastic structural optimizations of advanced HWB concepts. In this paper, the authors present substantial updates to the HCDstruct tool and related analysis, including: the addition of four inboard and eight outboard control surfaces and two all-movable tail/rudder assemblies, providing a full aeroservoelastic analysis capability; the implementation of asymmetric load cases for structural sizing applications; and a methodology for minimizing control surface actuation power using NASTRAN SOL 200 and HCDstruct's aeroservoelastic finite-element model (FEM).

  16. DEVELOPMENT OF OPERATIONAL CONCEPTS FOR ADVANCED SMRs: THE ROLE OF COGNITIVE SYSTEMS ENGINEERING

    SciTech Connect

    Jacques Hugo; David Gertman

    2014-04-01

    Advanced small modular reactors (AdvSMRs) will use advanced digital instrumentation and control systems, and make greater use of automation. These advances not only pose technical and operational challenges, but will inevitably have an effect on the operating and maintenance (O&M) cost of new plants. However, there is much uncertainty about the impact of AdvSMR designs on operational and human factors considerations, such as workload, situation awareness, human reliability, staffing levels, and the appropriate allocation of functions between the crew and various automated plant systems. Existing human factors and systems engineering design standards and methodologies are not current in terms of human interaction requirements for dynamic automated systems and are no longer suitable for the analysis of evolving operational concepts. New models and guidance for operational concepts for complex socio-technical systems need to adopt a state-of-the-art approach such as Cognitive Systems Engineering (CSE) that gives due consideration to the role of personnel. This approach we report on helps to identify and evaluate human challenges related to non-traditional concepts of operations. A framework - defining operational strategies was developed based on the operational analysis of Argonne National Laboratory’s Experimental Breeder Reactor-II (EBR-II), a small (20MWe) sodium-cooled reactor that was successfully operated for thirty years. Insights from the application of the systematic application of the methodology and its utility are reviewed and arguments for the formal adoption of CSE as a value-added part of the Systems Engineering process are presented.

  17. Development and proof-testing of advanced absorption refrigeration cycle concepts

    SciTech Connect

    Modahl, R.J.; Hayes, F.C. . Applied Unitary/Refrigeration Systems Div.)

    1992-03-01

    The overall objectives of this project are to evaluate, develop, and proof-test advanced absorption refrigeration cycles that are applicable to residential and commercial heat pumps for space conditioning. The heat pump system is to be direct-fired with natural gas and is to use absorption working fluids whose properties are known. Target coefficients of performance (COPs) are 1.6 at 47{degrees}F and 1.2 at 17{degrees} in the heating mode, and 0.7 at 95{degree}F in the cooling mode, including the effect of flue losses. The project is divided into three phases. Phase I entailed the analytical evaluation of advanced cycles and included the selection of preferred concepts for further development. Phase II involves the development and testing of critical components and of a complete laboratory breadboard version of the selected system. Phase III calls for the development of a prototype unit and is contingent on the successful completion of Phase II. This report covers Phase I work on the project. In Phase 1, 24 advanced absorption cycle/fluid combinations were evaluated, and computer models were developed to predict system performance. COP, theoretical pump power, and internal heat exchange were calculated for each system, and these calculations were used as indicators of operating and installed costs in order to rank the relative promise of each system. The highest ranking systems involve the cycle concept of absorber/generator heat exchange, generator heat exchanger/absorber heat exchange, regeneration, and resorption/desorption, in combination with the NH{sub 3}/H{sub 2}O/LiBr ternary absorption fluid mixture or with the NH{sub 3}/H{sub 2}O binary solution. Based upon these conclusions, the recommendation was made to proceed to Phase II, the laboratory breadboard proof-of- concept.

  18. Advanced Hybrid Spacesuit Concept Featuring Integrated Open Loop and Closed Loop Ventilation Systems

    NASA Technical Reports Server (NTRS)

    Daniel, Brian A.; Fitzpatrick, Garret R.; Gohmert, Dustin M.; Ybarra, Rick M.; Dub, Mark O.

    2013-01-01

    A document discusses the design and prototype of an advanced spacesuit concept that integrates the capability to function seamlessly with multiple ventilation system approaches. Traditionally, spacesuits are designed to operate both dependently and independently of a host vehicle environment control and life support system (ECLSS). Spacesuits that operate independent of vehicle-provided ECLSS services must do so with equipment selfcontained within or on the spacesuit. Suits that are dependent on vehicle-provided consumables must remain physically connected to and integrated with the vehicle to operate properly. This innovation is the design and prototype of a hybrid spacesuit approach that configures the spacesuit to seamlessly interface and integrate with either type of vehicular systems, while still maintaining the ability to function completely independent of the vehicle. An existing Advanced Crew Escape Suit (ACES) was utilized as the platform from which to develop the innovation. The ACES was retrofitted with selected components and one-off items to achieve the objective. The ventilation system concept was developed and prototyped/retrofitted to an existing ACES. Components were selected to provide suit connectors, hoses/umbilicals, internal breathing system ducting/ conduits, etc. The concept utilizes a lowpressure- drop, high-flow ventilation system that serves as a conduit from the vehicle supply into the suit, up through a neck seal, into the breathing helmet cavity, back down through the neck seal, out of the suit, and returned to the vehicle. The concept also utilizes a modified demand-based breathing system configured to function seamlessly with the low-pressure-drop closed-loop ventilation system.

  19. Advanced direct liquefaction concepts for PETC generic units. Final report, Phase I

    SciTech Connect

    1995-03-01

    The Advanced Concepts for Direct Coal Liquefaction program was initiated by the Department of Energy in 1991 to develop technologies that could significantly reduce the cost of producing liquid fuels by the direct liquefaction of coal. The advanced 2-stage liquefaction technology that was developed at Wilsonville over the past 10 years has contributed significantly toward decreasing the cost of producing liquids from coal to about $33/bbl. It remains, however, the objective of DOE to further reduce this cost to a level more competitive with petroleum based products. This project, among others, was initiated to investigate various alternative approaches to develop technologies that might ultimately lead to a 25 % reduction in cost of product. In this project a number of novel concepts were investigated, either individually or in a coupled configuration that had the potential to contribute toward meeting the DOE goal. The concepts included mature technologies or ones closely related to them, such as coal cleaning by oil agglomeration, fluid coking and distillate hydrotreating and dewaxing. Other approaches that were either embryonic or less developed were chemical pretreatment of coal to remove oxygen, and dispersed catalyst development for application in the 2-stage liquefaction process. This report presents the results of this project. It is arranged in four sections which were prepared by participating organizations responsible for that phase of the project. A summary of the overall project and the principal results are given in this section. First, however, an overview of the process economics and the process concepts that were developed during the course of this program is presented.

  20. Feasibility of a Networked Air Traffic Infrastructure Validation Environment for Advanced NextGen Concepts

    NASA Technical Reports Server (NTRS)

    McCormack, Michael J.; Gibson, Alec K.; Dennis, Noah E.; Underwood, Matthew C.; Miller,Lana B.; Ballin, Mark G.

    2013-01-01

    Abstract-Next Generation Air Transportation System (NextGen) applications reliant upon aircraft data links such as Automatic Dependent Surveillance-Broadcast (ADS-B) offer a sweeping modernization of the National Airspace System (NAS), but the aviation stakeholder community has not yet established a positive business case for equipage and message content standards remain in flux. It is necessary to transition promising Air Traffic Management (ATM) Concepts of Operations (ConOps) from simulation environments to full-scale flight tests in order to validate user benefits and solidify message standards. However, flight tests are prohibitively expensive and message standards for Commercial-off-the-Shelf (COTS) systems cannot support many advanced ConOps. It is therefore proposed to simulate future aircraft surveillance and communications equipage and employ an existing commercial data link to exchange data during dedicated flight tests. This capability, referred to as the Networked Air Traffic Infrastructure Validation Environment (NATIVE), would emulate aircraft data links such as ADS-B using in-flight Internet and easily-installed test equipment. By utilizing low-cost equipment that is easy to install and certify for testing, advanced ATM ConOps can be validated, message content standards can be solidified, and new standards can be established through full-scale flight trials without necessary or expensive equipage or extensive flight test preparation. This paper presents results of a feasibility study of the NATIVE concept. To determine requirements, six NATIVE design configurations were developed for two NASA ConOps that rely on ADS-B. The performance characteristics of three existing in-flight Internet services were investigated to determine whether performance is adequate to support the concept. Next, a study of requisite hardware and software was conducted to examine whether and how the NATIVE concept might be realized. Finally, to determine a business case

  1. Advanced Supersonic Nozzle Concepts: Experimental Flow Visualization Results Paired With LES

    NASA Astrophysics Data System (ADS)

    Berry, Matthew; Magstadt, Andrew; Stack, Cory; Gaitonde, Datta; Glauser, Mark; Syracuse University Team; The Ohio State University Team

    2015-11-01

    Advanced supersonic nozzle concepts are currently under investigation, utilizing multiple bypass streams and airframe integration to bolster performance and efficiency. This work focuses on the parametric study of a supersonic, multi-stream jet with aft deck. The single plane of symmetry, rectangular nozzle, displays very complex and unique flow characteristics. Flow visualization techniques in the form of PIV and schlieren capture flow features at various deck lengths and Mach numbers. LES is compared to the experimental results to both validate the computational model and identify limitations of the simulation. By comparing experimental results to LES, this study will help create a foundation of knowledge for advanced nozzle designs in future aircraft. SBIR Phase II with Spectral Energies, LLC under direction of Barry Kiel.

  2. Research directions and progress in the SERI advanced high efficiency concept program

    SciTech Connect

    Cole, L A; Benner, J P

    1984-06-01

    The inherent electro-optical properties of gallium arsenide (GaAs) and related III-V compounds make this class of semiconductors an optimum choice for use in very high efficiency solar cells. The ability to alloy GaAs with other column III and V elements while maintaining the single crystal zincblende structure allows the photovoltaic properties to be tailored to specific needs. The current understanding and control of the properties of these materials is more advanced than for any other semiconductor except single crystal silicon. For these reasons, the Advanced High Efficiency Concepts Program supports materials research to improve the properties of III-V semiconductors needed to achieve the maximum attainable photovoltaic conversion efficiencies.

  3. Draft Function Allocation Framework and Preliminary Technical Basis for Advanced SMR Concepts of Operations

    SciTech Connect

    Jacques Hugo; John Forester; David Gertman; Jeffrey Joe; Heather Medema; Julius Persensky; April Whaley

    2013-08-01

    This report presents preliminary research results from the investigation into the development of new models and guidance for Concepts of Operations in advanced small modular reactor (AdvSMR) designs. AdvSMRs are nuclear power plants (NPPs), but unlike conventional large NPPs that are constructed on site, AdvSMRs systems and components will be fabricated in a factory and then assembled on site. AdvSMRs will also use advanced digital instrumentation and control systems, and make greater use of automation. Some AdvSMR designs also propose to be operated in a multi-unit configuration with a single central control room as a way to be more cost-competitive with existing NPPs. These differences from conventional NPPs not only pose technical and operational challenges, but they will undoubtedly also have regulatory compliance implications, especially with respect to staffing requirements and safety standards.

  4. Stereotactic radiosurgery of glomus jugulare tumors: current concepts, recent advances and future perspectives.

    PubMed

    Sager, Omer; Dincoglan, Ferrat; Beyzadeoglu, Murat

    2015-01-01

    Stereotactic radiosurgery (SRS), a very highly focused form of therapeutic irradiation, has been widely recognized as a viable treatment option in the management of intracranial pathologies including benign tumors, malign tumors, vascular malformations and functional disorders. The applications of SRS are continuously expanding thanks to the ever-increasing advances and corresponding improvements in neuroimaging, radiation treatment techniques, equipment, treatment planning and delivery systems. In the context of glomus jugulare tumors (GJT), SRS is being more increasingly used both as the upfront management modality or as a complementary or salvage treatment option. As its safety and efficacy is being evident with compiling data from studies with longer follow-up durations, SRS appears to take the lead in the management of most patients with GJT. Herein, we address current concepts, recent advances and future perspectives in SRS of GJT in light of the literature. PMID:25768334

  5. Evaluation of advanced lift concepts and fuel conservative short-haul aircraft, volume 1

    NASA Technical Reports Server (NTRS)

    Renshaw, J. H.; Bowden, M. K.; Narucki, C. W.; Bennett, J. A.; Smith, P. R.; Ferrill, R. S.; Randall, C. C.; Tibbetts, J. G.; Patterson, R. W.; Meyer, R. T.

    1974-01-01

    The performance and economics of a twin-engine augmentor wing airplane were evaluated in two phases. Design aspects of the over-the-wing/internally blown flap hybrid, augmentor wing, and mechanical flap aircraft were investigated for 910 m. field length with parametric extension to other field lengths. Fuel savings achievable by application of advanced lift concepts to short-haul aircraft were evaluated and the effect of different field lengths, cruise requirements, and noise levels on fuel consumption and airplane economics at higher fuel prices were determined. Conclusions and recommendations are presented.

  6. Advanced Transportation System Studies. Technical Area 3: Alternate Propulsion Subsystem Concepts

    NASA Technical Reports Server (NTRS)

    Levack, Daniel J. H.

    2000-01-01

    The Alternate Propulsion Subsystem Concepts contract had seven tasks defined for this report. The tasks were: F-1A Restart Study, J-2S Restart Study, Propulsion Database Development, SSME Upper Stage Use, CERs for Liquid Propellant Rocket Engines, Advanced Low Cost Engines, and Tripropellant Comparison Study. The detailed study results, with the data to support the conclusions from various analyses, are being reported as a series of five separate Final Task Reports. Consequently, this volume only reports the required programmatic information concerning Computer Aided Design Documentation, and New Technology Reports. A detailed Executive Summary, covering all the tasks, is also available as Volume I of this report.

  7. Work Domain Analysis and Operational Concepts for Advanced Nuclear Power Plants

    SciTech Connect

    Jacques Hugo

    2001-02-01

    The nuclear industry is currently designing and building a new generation of reactors that will differ in important respects from the older generation. Differences in new plants will include different structural, functional, and environmental aspects, all of which are likely to have a significant impact on the way these plants are operated. In order to meet economic and safety objectives, these new reactors will all use advanced technologies to some extent, including new materials and advanced digital instrumentation and control systems. Examples of these advances include distribution of load-following demand among multiple units, different product streams (steam, process heat, or electricity), increased use of passive safety systems, high levels of automation with humans in supervisory roles, integration of computerized procedures for control room and field work, and remote surveillance and on-line monitoring. New technologies will affect not only operational strategies, but will also require a new approach to how functions are allocated to humans or machines to ensure optimal performance. There is still much uncertainty about the effect of large scale changes in plant design on operations and human tasks, such as workload, situation awareness, human reliability, staffing levels, and the appropriate allocation of functions between the crew and various automated plant systems. This uncertainty will remain until sound technical bases are developed for new operational concepts and strategies. Existing human factors and systems engineering design standards and methodologies are not current in terms of human interaction requirements for dynamic automated systems and are no longer suitable for the analysis of evolving operational concepts. Up-to-date models and guidance are required for the development of operational concepts for complex socio-technical systems. Designers need to be able to identify and evaluate specific human factors challenges related to non

  8. A demonstration of passive blade twist control using extension-twist coupling

    NASA Technical Reports Server (NTRS)

    Lake, R. C.; Nixon, M. W.; Wilbur, M. L.; Singleton, J. D.; Mirick, P. H.

    1992-01-01

    The feasibility of passive blade twist control using an extension-twist-coupled composite rotor blade design has been demonstrated. A set of low-twist model-scale helicopter rotor blades has been manufactured from existing molds with the objective of demonstrating this control concept. Hover testing of the set of blades demonstrated maximum twist changes of 5.24 deg for the ballasted blade configuration, and 2.54 deg for the unballasted configurations in the atmospheric test condition. These results compared well with those obtained from a detailed FEM analysis of the rotor blade. Aerodynamic-induced effects on the blade elastic twist were found to be minimal.

  9. Design and evaluation of low-cost stainless steel fiberglass foam blades for large wind driven generating systems

    NASA Technical Reports Server (NTRS)

    Eggert, W. S.

    1982-01-01

    A low cost wind turbine blade based on a stainless steel fiberglass foam Budd blade design concept, was evaluated for its principle characteristics, low cost features, and its advantages and disadvantages. A blade structure was designed and construction methods and materials were selected. A complete blade tooling concepts, various technical and economic analysis, and evaluations of the blade design were performed. A comprehensive fatigue test program is conducted to provide data to verify the design stress allowables.

  10. Turbine blade damping study

    NASA Technical Reports Server (NTRS)

    Dominic, R. J.

    1984-01-01

    Research results and progress on the performance of bladed systems is reported the different topics discussed include: the study of turbine blade damping; forced vibrations of friction damped beam moistures in two dimensions; and a users manual for a computer program for dynamic analysis of bladed systems.

  11. Turbine Blade Alloy

    NASA Technical Reports Server (NTRS)

    MacKay, Rebecca

    2001-01-01

    The High Speed Research Airfoil Alloy Program developed a fourth-generation alloy with up to an +85 F increase in creep rupture capability over current production airfoil alloys. Since improved strength is typically obtained when the limits of microstructural stability are exceeded slightly, it is not surprising that this alloy has a tendency to exhibit microstructural instabilities after high temperature exposures. This presentation will discuss recent results obtained on coated fourth-generation alloys for subsonic turbine blade applications under the NASA Ultra-Efficient Engine Technology (UEET) Program. Progress made in reducing microstructural instabilities in these alloys will be presented. In addition, plans will be presented for advanced alloy development and for computational modeling, which will aid future alloy development efforts.

  12. Advanced onboard storage concepts for natural gas-fueled automotive vehicles

    NASA Technical Reports Server (NTRS)

    Remick, R. J.; Elkins, R. H.; Camara, E. H.; Bulicz, T.

    1984-01-01

    The evaluation of several advanced concepts for storing natural gas at reduced pressure is presented. The advanced concepts include adsorption on high surface area carbon, adsorption in high porosity zeolite, storage in clathration compounds, and storage by dissolution in liquid solvents. High surface area carbons with high packing density are the best low pressure storage mediums. A simple mathematical model is used to compare adsorption storage on a state of the art carbon with compression storage. The model indicates that a vehicle using adsorption storage of natural gas at 3.6 MPa will have 36 percent of the range, on the EPA city cycle, of a vehicle operating on a compression storage system having the same physical size and a peak storage pressure of 21 MPa. Preliminary experiments and current literature suggest that the storage capacity of state of the art carbons could be improved by as much as 50 percent, and that adsorption systems having a capacity equal to compression storage at 14 MPa are possible without exceeding a maximum pressure of 3.6 MPa.

  13. Design procedures for compressor blades

    NASA Technical Reports Server (NTRS)

    Starken, H.

    1983-01-01

    The conventional methods for the design of the blades in the case of axial turbomachines are considered, taking into account difficulties concerning the determination of optimal blade profiles. These difficulties have been partly overcome as a consequence of the introduction of new numerical methods during the last few years. It is pointed out that, in the case of the subsonic range, a new procedure is now available for the determination of the form of blade profile on the basis of a given velocity distribution on the profile surface. The search for a profile form with favorable characteristics is consequently transformed into a search for a favorable velocity or pressure distribution on the blade. The distribution of velocities depends to a large degree on the characteristics of the profile boundary layers. The considered concept is not new. However, its practical implementation has only recently become possible. The employment of the new design procedure is illustrated with the aid of an example involving a concrete design problem.

  14. Advanced Transportation System Studies. Technical Area 3: Alternate Propulsion Subsystem Concepts. Volume 1; Executive Summary

    NASA Technical Reports Server (NTRS)

    Levack, Daniel J. H.

    2000-01-01

    The Alternate Propulsion Subsystem Concepts contract had seven tasks defined that are reported under this contract deliverable. The tasks were: FAA Restart Study, J-2S Restart Study, Propulsion Database Development. SSME Upper Stage Use. CERs for Liquid Propellant Rocket Engines. Advanced Low Cost Engines, and Tripropellant Comparison Study. The two restart studies, F-1A and J-2S, generated program plans for restarting production of each engine. Special emphasis was placed on determining changes to individual parts due to obsolete materials, changes in OSHA and environmental concerns, new processes available, and any configuration changes to the engines. The Propulsion Database Development task developed a database structure and format which is easy to use and modify while also being comprehensive in the level of detail available. The database structure included extensive engine information and allows for parametric data generation for conceptual engine concepts. The SSME Upper Stage Use task examined the changes needed or desirable to use the SSME as an upper stage engine both in a second stage and in a translunar injection stage. The CERs for Liquid Engines task developed qualitative parametric cost estimating relationships at the engine and major subassembly level for estimating development and production costs of chemical propulsion liquid rocket engines. The Advanced Low Cost Engines task examined propulsion systems for SSTO applications including engine concept definition, mission analysis. trade studies. operating point selection, turbomachinery alternatives, life cycle cost, weight definition. and point design conceptual drawings and component design. The task concentrated on bipropellant engines, but also examined tripropellant engines. The Tripropellant Comparison Study task provided an unambiguous comparison among various tripropellant implementation approaches and cycle choices, and then compared them to similarly designed bipropellant engines in the

  15. Tribopolymerization: An advanced lubrication concept for automotive engines and systems of the future

    SciTech Connect

    Furey, M.J.; Kajdas, C.; Kaltenbach, K.W.

    1997-12-31

    Advanced lubrication technologies based on the concept of tribopolymerization as a mechanism of boundary lubrication are described. Advantages of this approach as well as potential applications which could have an impact on the design, manufacture, and performance of existing and future automotive engines are presented and discussed. Tribopolymerization, a novel concept of molecular design developed by Furey and Kajdas, involves the continuous formation of thin polymeric films on rubbing surfaces; the protective films formed are self-replenishing. The antiwear compounds developed from this technology are effective with metals as well as ceramics and in the liquid as well as vapor phases. Furthermore, they are ashless and contain no harmful phosphorus or sulfur; and many are biodegradable. Thus, potential applications of this technology are diverse and include a variety of cost/performance/energy/environmental advantages. Examples include the following: (a) machining and cutting applications using thin films to reduce friction and ceramic tool wear; (b) the lubrication of ceramic engines (e.g., low heat rejection diesel engines) or ceramic components; (c) the development of ashless lubricants for existing and future automotive engines to reduce exhaust catalyst poisoning and environmental emissions; (d) ashless antiwear or ``lubricity`` additives for fuels, including gasoline, diesel and jet fuel; (e) vapor phase applications of this technology to high temperature gaseous systems or to fuel injector wear problems associated with the use of natural gas engines; and (f) the use of the concept of tribopolymerization as an enabling technology in the development of new engines and new automotive propulsion systems.

  16. Draft Function Allocation Framework and Preliminary Technical Basis for Advanced SMR Concepts of Operations

    SciTech Connect

    Jacques Hugo; John Forester; David Gertman; Jeffrey Joe; Heather Medema; Julius Persensky; April Whaley

    2013-04-01

    This report presents preliminary research results from the investigation in to the development of new models and guidance for concepts of operations (ConOps) in advanced small modular reactor (aSMR) designs. In support of this objective, three important research areas were included: operating principles of multi-modular plants, functional allocation models and strategies that would affect the development of new, non-traditional concept of operations, and the requiremetns for human performance, based upon work domain analysis and current regulatory requirements. As part of the approach for this report, we outline potential functions, including the theoretical and operational foundations for the development of a new functional allocation model and the identification of specific regulatory requirements that will influence the development of future concept of operations. The report also highlights changes in research strategy prompted by confirmationof the importance of applying the work domain analysis methodology to a reference aSMR design. It is described how this methodology will enrich the findings from this phase of the project in the subsequent phases and help in identification of metrics and focused studies for the determination of human performance criteria that can be used to support the design process.

  17. Generic Repository Concepts and Thermal Analysis for Advanced Fuel Cycles - 12477

    SciTech Connect

    Hardin, Ernest; Blink, James; Carter, Joe; Fratoni, Massimiliano; Greenberg, Harris; Sutton, Mark; Howard, Robert

    2012-07-01

    A geologic disposal concept for spent nuclear fuel (SNF) or high-level waste (HLW) consists of three components: waste inventory, geologic setting, and concept of operations. A set of reference geologic disposal concepts has been developed by the U.S. Department of Energy (DOE), Used Fuel Disposition campaign. Reference concepts are identified for crystalline rock, clay/shale, bedded salt, and deep borehole (crystalline basement) geologic settings. These were analyzed for waste inventory cases representing a range of waste types that could be produced by advanced nuclear fuel cycles. Concepts of operation consisting of emplacement mode, repository layout, and engineered barrier descriptions, were selected based on international progress. All of these disposal concepts are enclosed emplacement modes, whereby waste packages are in direct contact with encapsulating engineered or natural materials. Enclosed modes have less capacity to dissipate heat than open modes such as that proposed for a repository at Yucca Mountain. Thermal analysis has identified important relationships between waste package size and capacity, and the duration of surface decay storage needed to meet temperature limits for different disposal concepts. For the crystalline rock and clay/shale repository concepts, a waste package surface temperature limit of 100 deg. C was assumed to prevent changes in clay-based buffer material or clay-rich host rock. Surface decay storage of 50 to 100 years is needed for disposal of high-burnup LWR SNF in 4-PWR packages, or disposal of HLW glass from reprocessing LWR uranium oxide (UOX) fuel. High-level waste (HLW) from reprocessing of metal fuel used in a fast reactor could be disposed after decay storage of 50 years or less. For disposal in salt the rock thermal conductivity is significantly greater, and higher temperatures (200 deg. C) can be tolerated at the waste package surface. Decay storage of 10 years or less is needed for high-burnup LWR SNF in 4-PWR

  18. Evaluation of innovative concepts for semi-active and active rotorcraft control

    NASA Astrophysics Data System (ADS)

    Van Weddingen, Yannick

    2011-12-01

    Lead-lag dampers are present in most rotor systems to provide the desired level of damping for all flight conditions. These dampers are critical components of the rotor system, and the performance of semi-active Coulomb friction-based lead-lag dampers is examined for the UH-60 aircraft. The concept of adaptive damping, or "damping on demand," is discussed for both ground resonance and forward flight. The concept of selective damping is also assessed, and shown to face many challenges. In rotorcraft flight dynamics, optimized warping twist change is a potentially enabling technology to improve overall rotorcraft performance. Research efforts in recent years have led to the application of active materials for rotorcraft blade actuation. An innovative concept is proposed wherein the typically closed section blade is cut open to create a torsionally compliant structure that acts as its own amplification device; deformation of the blade is dynamically controlled by out-of-plane warping. Full-blade warping is shown to have the potential for great design flexibility. Recent advances in rotorcraft blade design have also focused on variable-camber airfoils, particularly concepts involving "truss-core" configurations. One promising concept is the use of hexagonal chiral lattice structures in continuously deformable helicopter blades. The static behavior of passive and active chiral networks using piezoelectric actuation strategies is investigated, including under typical aerodynamic load levels. The analysis is then extended to the dynamic response of active chiral networks in unsteady aerodynamic environments.

  19. Advanced Concepts, Technologies and Flight Experiments for NASA's Earth Science Enterprise

    NASA Technical Reports Server (NTRS)

    Meredith, Barry D.

    2000-01-01

    Over the last 25 years, NASA Langley Research Center (LaRC) has established a tradition of excellence in scientific research and leading-edge system developments, which have contributed to improved scientific understanding of our Earth system. Specifically, LaRC advances knowledge of atmospheric processes to enable proactive climate prediction and, in that role, develops first-of-a-kind atmospheric sensing capabilities that permit a variety of new measurements to be made within a constrained enterprise budget. These advances are enabled by the timely development and infusion of new, state-of-the-art (SOA), active and passive instrument and sensor technologies. In addition, LaRC's center-of-excellence in structures and materials is being applied to the technological challenges of reducing measurement system size, mass, and cost through the development and use of space-durable materials; lightweight, multi-functional structures; and large deployable/inflatable structures. NASA Langley is engaged in advancing these technologies across the full range of readiness levels from concept, to components, to prototypes, to flight experiments, and on to actual science mission infusion. The purpose of this paper is to describe current activities and capabilities, recent achievements, and future plans of the integrated science, engineering, and technology team at Langley Research Center who are working to enable the future of NASA's Earth Science Enterprise.

  20. Advanced payload concepts and system architecture for emerging services in Indian National Satellite Systems

    NASA Astrophysics Data System (ADS)

    Balasubramanian, E. P.; Rao, N. Prahlad; Sarkar, S.; Singh, D. K.

    2008-07-01

    Over the past two decades Indian Space Research Organization (ISRO) has developed and operationalized satellites to generate a large capacity of transponders for telecommunication service use in INSAT system. More powerful on-board transmitters are built to usher-in direct-to-home broadcast services. These have transformed the Satcom application scenario in the country. With the proliferation of satellite technology, a shift in the Indian market is witnessed today in terms of demand for new services like Broadband Internet, Interactive Multimedia, etc. While it is imperative to pay attention to market trends, ISRO is also committed towards taking the benefits of technological advancement to all round growth of our population, 70% of which dwell in rural areas. The initiatives already taken in space application related to telemedicine, tele-education and Village Resource Centres are required to be taken to a greater height of efficiency. These targets pose technological challenges to build a large capacity and cost-effective satellite system. This paper addresses advanced payload concepts and system architecture along with the trade-off analysis on design parameters in proposing a new generation satellite system capable of extending the reach of the Indian broadband structure to individual users, educational and medical institutions and enterprises for interactive services. This will be a strategic step in the evolution of INSAT system to employ advanced technology to touch every human face of our population.

  1. Advanced Technology Subsonic Transport Study: N+3 Technologies and Design Concepts

    NASA Technical Reports Server (NTRS)

    Raymer, Daniel P.; Wilson, Jack; Perkins, H. Douglas; Rizzi, Arthur; Zhang, Mengmeng; RamirezPuentes, Alfredo

    2011-01-01

    Conceptual Research Corporation, the Science of the Possible, has completed a two-year study of concepts and technologies for future airliners in the 180-passenger class. This NASA-funded contract was primarily focused on the ambitious goal of a 70 percent reduction in fuel consumption versus the market-dominating Boeing 737-800. The study is related to the N+3 contracts awarded in 2008 by NASA s Aeronautics Research Mission Directorate to teams led by Boeing, GE Aviation, MIT, and Northrop Grumman, but with more modest goals and funding. CRC s contract featured a predominant emphasis on propulsion and fuel consumption, but since fuel consumption depends upon air vehicle design as much as on propulsion technology, the study included notional vehicle design, analysis, and parametric studies. Other NASA goals including NOx and noise reduction are of long-standing interest but were not highlighted in this study, other than their inclusion in the propulsion system provided to CRC by NASA. The B-737-800 was used as a benchmark, parametric tool, and design point of departure. It was modeled in the RDS-Professional aircraft design software then subjected to extensive parametric variations of parasitic drag, drag-due-to-lift, specific fuel consumption, and unsized empty weight. These studies indicated that the goal of a 70 percent reduction in fuel consumption could be attained with roughly a 30 percent improvement in all four parameters. The results were then fit to a Response Surface and coded for ease of use in subsequent trade studies. Potential technologies to obtain such savings were identified and discussed. More than 16 advanced concept designs were then prepared, attempting to investigate almost every possible emerging concept for application to this class airliner. A preliminary assessment of these concepts was done based on their total wetted area after design normalization of trimmed maximum lift. This assessment points towards a Tailless Airliner concept which

  2. Periodic control of the individual-blade-control helicopter rotor. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Mckillip, R. M., Jr.

    1984-01-01

    Results of an investigation into methods of controller design for an individual helicopter rotor blade in the high forward-flight speed regime are described. This operating condition poses a unique control problem in that the perturbation equations of motion are linear with coefficients that vary periodically with time. The design of a control law was based on extensions to modern multivariate synthesis techniques and incorporated a novel approach to the reconstruction of the missing system state variables. The controller was tested on both an electronic analog computer simulation of the out-of-plane flapping dynamics, and on a four foot diameter single-bladed model helicopter rotor in the M.I.T. 5x7 subsonic wind tunnel at high levels of advance ratio. It is shown that modal control using the IBC concept is possible over a large range of advance ratios with only a modest amount of computational power required.

  3. Study of advanced fuel system concepts for commercial aircraft and engines

    NASA Technical Reports Server (NTRS)

    Versaw, E. F.; Brewer, G. D.; Byers, W. D.; Fogg, H. W.; Hanks, D. E.; Chirivella, J.

    1983-01-01

    The impact on a commercial transport aircraft of using fuels which have relaxed property limits relative to current commercial jet fuel was assessed. The methodology of the study is outlined, fuel properties are discussed, and the effect of the relaxation of fuel properties analyzed. Advanced fuel system component designs that permit the satisfactory use of fuel with the candidate relaxed properties in the subject aircraft are described. The two fuel properties considered in detail are freezing point and thermal stability. Three candidate fuel system concepts were selected and evaluated in terms of performance, cost, weight, safety, and maintainability. A fuel system that incorporates insulation and electrical heating elements on fuel tank lower surfaces was found to be most cost effective for the long term.

  4. Advanced direct liquefaction concepts for PETC generic units. Quarterly technical progress report, January--March 1992

    SciTech Connect

    Not Available

    1992-04-01

    In the Advance Coal Liquefaction Concept Proposal (ACLCP) carbon monoxide (CO) and water have been proposed as the primary reagents in the pretreatment process. The main objective of this project is to develop a methodology for pretreating coal under mild conditions based on a combination of existing processes which have shown great promise in liquefaction, extraction and pyrolysis studies. The aim of this pretreatment process is to partially depolymerise the coal, eliminate oxygen and diminish the propensity for retograde reactions during subsequent liquefaction. The desirable outcome of the CO pretreatment step should be: (1) enhanced liquefaction activity and/or selectivity toward products of higher quality due to chemical modification of the coal structure; (2) cleaner downstream products; (3) overall improvement in operability and process economics.

  5. Development of advanced concepts for DIR-MCFC cogeneration applications in the European Market

    SciTech Connect

    Kortbeek, P.J.; Ottervanger, R.G.; Dicks, A.L.

    1996-12-31

    Early 1996 a three year (1996 - 1998) joint European project was launched under the name {open_quote}Advanced DIR-MCFC Development{close_quote}, aiming at the development of Direct Internal Reforming (DIR) Molten Carbonate Fuel Cell (MCFC) systems for cogeneration applications for the European market. In this project participate: Brandstofcel Nederland BV (BCN), British Gas pic (BG), Gaz de France (GDF), Netherlands Energy Research foundation (ECN), Stork, Royal Schelde and Sydkraft AB. The European Fuel Cell User Group (EFCUG) supports the project as an advisory board. Whereas the US and Japanese programmes are aimed at large-scale demonstrations of the MCFC technology, this project focusses on the development of concepts and technology, required for MCFC systems that will be competative on the cogeneration market. The project partners provide the essential expertise: from end-user, system engineering, stack development up to fundamental material research.

  6. The x-ray advanced concepts testbed (XACT) sounding rocket payload

    NASA Astrophysics Data System (ADS)

    Gendreau, Keith; Arzoumanian, Zaven; Asami, Fumi; Baker, Robert; Balsamo, Erin; Black, Kevin; Duran-Aviles, Carlos; Enoto, Teruaki; Gregory, Kyle; Hahne, Devin; Hayato, Asami; Hill, Joe; Huegel, Fred; Iwahashi, Takanori; Iwakiri, Wataru; Jahoda, Keith; Jalota, Lalit; Kaaret, Philip; Kaneko, Kenta; Kenyon, Steven; Kitaguchi, Takao; Koenecke, Richard; Kohmura, Takayoshi; Okajima, Takashi; Olsen, Larry; Porter, F. Scott; Rush, Kurt; Serlemitsos, Peter; Soong, Yang; Takeuchi, Yoko; Tamagawa, Toru; Yamada, Shin'ya; Yoshikawa, Akifumi

    2012-09-01

    The scientific objective of the X-ray Advanced Concepts Testbed (XACT) is to measure the X-ray polarization properties of the Crab Nebula, the Crab pulsar, and the accreting binary Her X-1. Polarimetry is a powerful tool for astrophysical investigation that has yet to be exploited in the X-ray band, where it promises unique insights into neutron stars, black holes, and other extreme-physics environments. With powerful new enabling technologies, XACT will demonstrate X-ray polarimetry as a practical and flight-ready astronomical technique. Additional technologies that XACT will bring to flight readiness will also provide new X-ray optics and calibration capabilities for NASA missions that pursue space-based X-ray spectroscopy, timing, and photometry.

  7. Development of a VOR/DME model for an advanced concepts simulator

    NASA Technical Reports Server (NTRS)

    Steinmetz, G. G.; Bowles, R. L.

    1984-01-01

    The report presents a definition of a VOR/DME, airborne and ground systems simulation model. This description was drafted in response to a need in the creation of an advanced concepts simulation in which flight station design for the 1980 era can be postulated and examined. The simulation model described herein provides a reasonable representation of VOR/DME station in the continental United States including area coverage by type and noise errors. The detail in which the model has been cast provides the interested researcher with a moderate fidelity level simulator tool for conducting research and evaluation of navigator algorithms. Assumptions made within the development are listed and place certain responsibilities (data bases, communication with other simulation modules, uniform round earth, etc.) upon the researcher.

  8. AICD -- Advanced Industrial Concepts Division Biological and Chemical Technologies Research Program. 1993 Annual summary report

    SciTech Connect

    Petersen, G.; Bair, K.; Ross, J.

    1994-03-01

    The annual summary report presents the fiscal year (FY) 1993 research activities and accomplishments for the United States Department of Energy (DOE) Biological and Chemical Technologies Research (BCTR) Program of the Advanced Industrial Concepts Division (AICD). This AICD program resides within the Office of Industrial Technologies (OIT) of the Office of Energy Efficiency and Renewable Energy (EE). The annual summary report for 1993 (ASR 93) contains the following: A program description (including BCTR program mission statement, historical background, relevance, goals and objectives), program structure and organization, selected technical and programmatic highlights for 1993, detailed descriptions of individual projects, a listing of program output, including a bibliography of published work, patents, and awards arising from work supported by BCTR.

  9. Preliminary Structural Design of Composite Blades for Two- and Three-Blade Rotors

    SciTech Connect

    Bir, G.; Migliore, P.

    2004-09-01

    A computerized method has been developed to aid in the preliminary design of composite wind turbine blades. The method allows for arbitrary specification of the chord, twist, and airfoil geometry along the blade and an arbitrary number of shear webs. Given the blade external geometry description and its design load distribution, the Fortran code uses ultimate-strength and buckling-resistance criteria to compute the design thickness of load-bearing composite laminates. The code also includes an analysis option to obtain blade properties if a composite laminates schedule is prescribed. These properties include bending stiffness, torsion stiffness, mass, moments of inertia, elastic-axis offset, and center-of-mass offset along the blade. Nonstructural materials-gelcoat, nexus, and bonding adhesive-are also included for computation of mass. The code includes an option to format the output properties that can be directly input to advanced aeroelastic codes. This report summarizes the structural layout of composite laminates within the blade, the design approach, and the computational process. Finally, we present the results of two composite blades designed using this code in support of a project covering comparison of two- and three-blade rotors for a hypothetical turbine.

  10. Mission planning and scheduling concept for the Advanced X-ray Astrophysics Facility (AXAF)

    NASA Technical Reports Server (NTRS)

    Newhouse, M.; Guffin, O. T.

    1994-01-01

    Projected for launch in the latter part of 1998, the Advanced X-ray Astrophysics Facility (AXAF), the third satellite in the Great Observatory series, promises to dramatically open the x-ray sky as the Hubble and Compton observatories have done in their respective realms. Unlike its companions, however, AXAF will be placed in a high altitude, highly elliptical orbit (10,000 x 100,000 km), and will therefore be subject to its own unique environment, spacecraft and science instrument constraints and communication network interactions. In support of this mission, ground operations personnel have embarked on the development of the AXAF Offline System (OFLS), a body of software divided into four basic functional elements: (1) Mission Planning and Scheduling, (2) Command Management, (3) Altitude Determination and Sensor Calibration and (4) Spacecraft Support and Engineering Analysis. This paper presents an overview concept for one of these major elements, the Mission Planning and Scheduling subsystem (MPS). The derivation of this concept is described in terms of requirements driven by spacecraft and science instrument characteristics, orbital environment and ground system capabilities. The flowdown of these requirements through the systems analysis process and the definition of MPS interfaces has resulted in the modular grouping of functional subelements depicted in the design implementation approach. The rationale for this design solution is explained and capabilities for the initial prototype system are proposed from the user perspective.

  11. Composite transport wing technology development: Design development tests and advanced structural concepts

    NASA Technical Reports Server (NTRS)

    Griffin, Charles F.; Harvill, William E.

    1988-01-01

    Numerous design concepts, materials, and manufacturing methods were investigated for the covers and spars of a transport box wing. Cover panels and spar segments were fabricated and tested to verify the structural integrity of design concepts and fabrication techniques. Compression tests on stiffened panels demonstrated the ability of graphite/epoxy wing upper cover designs to achieve a 35 percent weight savings compared to the aluminum baseline. The impact damage tolerance of the designs and materials used for these panels limits the allowable compression strain and therefore the maximum achievable weight savings. Bending and shear tests on various spar designs verified an average weight savings of 37 percent compared to the aluminum baseline. Impact damage to spar webs did not significantly degrade structural performance. Predictions of spar web shear instability correlated well with measured performance. The structural integrity of spars manufactured by filament winding equalled or exceeded those fabricated by hand lay-up. The information obtained will be applied to the design, fabrication, and test of a full-scale section of a wing box. When completed, the tests on the technology integration box beam will demonstrate the structural integrity of an advanced composite wing design which is 25 percent lighter than the metal baseline.

  12. Tradespace Exploration of Distributed Propulsors for Advanced On-Demand Mobility Concepts

    NASA Technical Reports Server (NTRS)

    Borer, Nicholas K.; Moore, Mark D.; Turnbull, Andrew R.

    2014-01-01

    Combustion-based sources of shaft power tend to significantly penalize distributed propulsion concepts, but electric motors represent an opportunity to advance the use of integrated distributed propulsion on an aircraft. This enables use of propellers in nontraditional, non-thrust-centric applications, including wing lift augmentation, through propeller slipstream acceleration from distributed leading edge propellers, as well as wingtip cruise propulsors. Developing propellers for these applications challenges long-held constraints within propeller design, such as the notion of optimizing for maximum propulsive efficiency, or the use of constant-speed propellers for high-performance aircraft. This paper explores the design space of fixed-pitch propellers for use as (1) lift augmentation when distributed about a wing's leading edge, and (2) as fixed-pitch cruise propellers with significant thrust at reduced tip speeds for takeoff. A methodology is developed for evaluating the high-level trades for these types of propellers and is applied to the exploration of a NASA Distributed Electric Propulsion concept. The results show that the leading edge propellers have very high solidity and pitch well outside of the empirical database, and that the cruise propellers can be operated over a wide RPM range to ensure that thrust can still be produced at takeoff without the need for a pitch change mechanism. To minimize noise exposure to observers on the ground, both the leading edge and cruise propellers are designed for low tip-speed operation during takeoff, climb, and approach.

  13. Aerodynamic Design Study of an Advanced Active Twist Rotor

    NASA Technical Reports Server (NTRS)

    Sekula, Martin K.; Wilbur, Matthew L.; Yeager, William T., Jr.

    2003-01-01

    An Advanced Active Twist Rotor (AATR) is currently being developed by the U.S. Army Vehicle Technology Directorate at NASA Langley Research Center. As a part of this effort, an analytical study was conducted to determine the impact of blade geometry on active-twist performance and, based on those findings, propose a candidate aerodynamic design for the AATR. The process began by creating a baseline design which combined the dynamic design of the original Active Twist Rotor and the aerodynamic design of a high lift rotor concept. The baseline model was used to conduct a series of parametric studies to examine the effect of linear blade twist and blade tip sweep, droop, and taper on active-twist performance. Rotor power requirements and hub vibration were also examined at flight conditions ranging from hover to advance ratio = 0.40. A total of 108 candidate designs were analyzed using the second-generation version of the Comprehensive Analytical Model of Rotorcraft Aerodynamics and Dynamics (CAMRAD II) code. The study concluded that the vibration reduction capabilities of a rotor utilizing controlled, strain-induced twisting are enhanced through the incorporation of blade tip sweep, droop, and taper into the blade design, while they are degraded by increasing the nose-down linear blade twist. Based on the analysis of rotor power, hub vibration, and active-twist response, a candidate aerodynamic design for the AATR consisting of a blade with approximately 10 degrees of linear blade twist and a blade tip design with 30 degree sweep, 10 degree droop, and 2.5:1 taper ratio over the outer five percent of the blade is proposed.

  14. Design, simulation and evaluation of advanced display concepts for the F-16 control configured vehicle

    NASA Technical Reports Server (NTRS)

    Klein, R. W.; Hollister, W. M.

    1982-01-01

    Advanced display concepts to augment the tracking ability of the F-16 Control Configured Vehicle (CCV) were designed, simulated, and evaluated. A fixed-base simulator was modified to represent the F-16 CCV. An isometric sidearm control stick and two-axis CCV thumb button were installed in the cockpit. The forward cockpit CRT was programmed to present an external scene (numbered runway, horizon) and the designed Heads Up Display. The cockpit interior was modified to represent a fighter and the F-16 CCV dynamics and direct lift and side force modes were programmed. Compensatory displays were designed from man-machine considerations. Pilots evaluated the Heads up Display and compensatory displays during simulated descents in the presence of several levels of filtered, zero-mean winds gusts. During a descent from 2500 feet to the runway, the pilots tracked a point on the runway utilizing the basic F-16, F-16 CCV, and F-16 CCV with advanced displays. Substantial tracking improvements resulted utilizing the CCV modes, and the displays were found to even further enhance the tracking ability of the F-16 CCV.

  15. A 100 MWe advanced sodium-cooled fast reactor core concept

    SciTech Connect

    Kim, T. K.; Grandy, C.; Hill, R. N.

    2012-07-01

    An Advanced sodium-cooled Fast Reactor core concept (AFR-100) was developed targeting a small electrical grid to be transportable to the plant site and operable for a long time without frequent refueling. The reactor power rating was strategically decided to be 100 MWe, and the core barrel diameter was limited to 3.0 m for transportability. The design parameters were determined by relaxing the peak fast fluence limit and bulk coolant outlet temperature to beyond irradiation experience assuming that advanced cladding and structural materials developed under US-DOE programs would be available when the AFR-100 is deployed. With a de-rated power density and U-Zr binary metallic fuel, the AFR-100 can maintain criticality for 30 years without refueling. The average discharge burnup of 101 MWd/kg is comparable to conventional design values, but the peak discharge fast fluence of {approx}6x10{sup 23} neutrons/cm{sup 2} is beyond the current irradiation experiences with HT-9 cladding. The evaluated reactivity coefficients provide sufficient negative feedbacks and the reactivity control systems provide sufficient shutdown margins. The integral reactivity parameters obtained from quasi-static reactivity balance analysis indicate that the AFR-100 meets the sufficient conditions for acceptable asymptotic core outlet temperature following postulated unprotected accidents. Additionally, the AFR-100 has sufficient thermal margins by grouping the fuel assemblies into eight orifice zones. (authors)

  16. Screens Would Protect Wind-Tunnel Fan Blades

    NASA Technical Reports Server (NTRS)

    Farmer, Moses G.

    1992-01-01

    Butterfly screen installed in wind tunnel between test section and fan blades to prevent debris from reaching fan blades if model structure fails. Protective screens deployed manually or automatically. Concept beneficial anywhere wind tunnels employed. Also useful in areas outside of aerospace industry, such as in airflow design of automobiles and other vehicles.

  17. Affordable In-Space Transportation Phase 2: An Advanced Concepts Project

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The Affordable In-Space Transportation (AIST) program was established by the NASA Office of Space Access to improve transportation and lower the costs from Low Earth Orbit (LEO) to Geostationary Earth Orbit (GEO) and beyond (to Lunar orbit, Mars orbit, inner solar system missions, and return to LEO). A goal was established to identify and develop radically innovative concepts for new upper stages for Reusable Launch Vehicles (RLV) and Highly Reusable Space Transportation (HRST) systems. New architectures and technologies are being identified which have the potential to meet a cost goal of $1,000 to $2,000 per pound for transportation to GEO and beyond for overall mission cost (including the cost to LEO). A Technical Interchange Meeting (TTM) was held on October 16 and 17, 1996 in Huntsville, Alabama to review previous studies, present advanced concepts and review technologies that could be used to meet the stated goals. The TIN4 was managed by NASA-Marshall Space Flight Center (MSFC) Advanced Concepts Office with Mr. Alan Adams providing TIM coordination. Mr. John C. Mankins of NASA Headquarters provided overall sponsorship. The University of Alabama in Huntsville (UAH) Propulsion Research Center hosted the TIM at the UAH Research Center. Dr. Clark Hawk, Center Director, was the principal investigator. Technical support was provided by Christensen Associates. Approximately 70 attendees were present at the meeting. This Executive Summary provides a record of the key discussions and results of the TIN4 in a summary for-mat. It incorporates the response to the following basic issues of the TDVL which addressed the following questions: 1. What are the cost drivers and how can they be reduced? 2. What are the operational issues and their impact on cost? 3. What is the current technology readiness level (TRL) and what will it take to reach TRL 6? 4. What are the key enabling technologies and sequence for their accomplishment? 5 . What is the proposed implementation time

  18. Affordable In-Space Transportation. Phase 2; An Advanced Concepts Project

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The Affordable In-Space Transportation (AIST) program was established by the NASA Office of Space Access to improve transportation and lower the costs from Low Earth Orbit (LEO) to Geostationary Earth Orbit (GEO) and beyond (to Lunar orbit, Mars orbit, inner solar system missions, and return to LEO). A goal was established to identify and develop radically innovative concepts for new upper stages for Reusable Launch Vehicles (RLV) and Highly Reusable Space Transportation (HRST) systems. New architectures and technologies are being identified which have the potential to meet a cost goal of $1,000 to $2,000 per pound for transportation to GEO and beyond for overall mission cost (including the cost to LEO). A Technical Interchange Meeting (ITM) was held on October 16 and 17, 1996 in Huntsville, Alabama to review previous studies, present advanced concepts and review technologies that could be used to meet the stated goals. The TIM was managed by NASA-Mar-shaU Space Flight Center (MSFC) Advanced Concepts Office with Mr. Alan Adams providing TIM coordination. Mr. John C. Manidns of NASA Headquarters provided overall sponsorship. The University of Alabama in Huntsville (UAH) Propulsion Research Center hosted the TM at the UAH Research Center. Dr. Clark Hawk, Center Director, was the principal investigator. Technical support was provided by Christensen Associates. Approximately 70 attendees were present at the meeting. This Executive Summary provides a record of the key discussions and results of the TIM in a summary format. It incorporates the response to the following basic issues of the TPA, which addressed the following questions: 1. What are the cost drivers and how can they be reduced? 2. What are the operational issues and their impact on cost? What is the current Technology Readiness Level (TRL) and what will it take to reach TRL 6? 4. What are the key enabling technologies and sequence for their accomplishment? 5. What is the proposed implementation time frame

  19. Ceramic blade attachment system

    DOEpatents

    Shaffer, James E.

    1995-01-01

    A turbine blade having a preestablished rate of thermal expansion is attached to a turbine disc having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade and forms a turbine assembly. The turbine blade has a root portion defining a pair of sides having a pair of grooves therein. The turbine assembly includes a pair of flanges between which the turbine blades are positioned. Each of the pair of flanges has a plurality of grooves defined therein. The grooves within the pair of flanges are aligned with the grooves in the blades and have a space formed therebetween. A plurality of spherical balls are positioned within the space. The plurality of spherical balls has a preestablished rate of thermal expansion being equal to the preestablished rate of thermal expansion of the turbine blade.

  20. Ceramic blade attachment system

    DOEpatents

    Shaffer, J.E.

    1995-07-11

    A turbine blade having a preestablished rate of thermal expansion is attached to a turbine disc having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade and forms a turbine assembly. The turbine blade has a root portion defining a pair of sides having a pair of grooves therein. The turbine assembly includes a pair of flanges between which the turbine blades are positioned. Each of the pair of flanges has a plurality of grooves defined therein. The grooves within the pair of flanges are aligned with the grooves in the blades and have a space formed therebetween. A plurality of spherical balls are positioned within the space. The plurality of spherical balls has a preestablished rate of thermal expansion being equal to the preestablished rate of thermal expansion of the turbine blade. 4 figs.

  1. Extension-twist coupling optimization in composite rotor blades

    NASA Astrophysics Data System (ADS)

    Ozbay, Serkan

    2005-07-01

    For optimal rotor performance in a tiltrotor aircraft the difference in the inflow and the rotor speeds between the hover and cruise flight modes suggests different blade twist and chord distributions. The blade twist rates in current tiltrotor applications are defined based upon a compromise between the figure of merit in hover and propeller efficiency in airplane mode. However, when each operation mode is considered separately the optimum blade distributions are found to be considerably different. Passive blade twist control, which uses the inherent variation in centrifugal forces on a rotor blade to achieve optimum blade twist distributions in each flight mode through the use of extension-twist coupled composite rotor blades, has been considered for performance improvement of tiltrotor aircraft over the last two decades. The challenge for this concept is to achieve the desired twisting deformations in the rotor blade without altering the aeroelastic characteristics of the vehicle. A concept referred to as the sliding mass concept is proposed in this work in order to increase the twist change with rotor speed for a closed-cell composite rotor blade cross-section to practical levels for performance improvement in a tiltrotor aircraft. The concept is based on load path changes for the centrifugal forces by utilizing non-structural masses readily available on a conventional blade, such as the leading edge balancing mass. A multilevel optimization technique based on the simulated annealing method is applied to improve the performance of the XV15 tiltrotor aircraft. A cross-sectional analysis tool, VABS together with a multibody dynamics code, DYMORE are integrated into the optimization process. The optimization results revealed significant improvements in the power requirement in hover while preserving cruise efficiency. It is also shown that about 21% of the improvement is provided through the sliding mass concept pointing to the additional flexibility the concept

  2. Rotor blade dynamic design

    NASA Technical Reports Server (NTRS)

    Pritchard, Jocelyn I.; Adelman, Howard M.; Mantay, Wayne R.

    1989-01-01

    The rotor dynamic design considerations are essentially limitations on the vibratory response of the blades which in turn limit the dynamic excitation of the fuselage by forces and moments transmitted to the hub. Quantities which are associated with the blade response and which are subject to design constraints are discussed. These include blade frequencies, vertical and inplane hub shear, rolling and pitching moments, and aeroelastic stability margin.

  3. Growian rotor blades: Production development, construction and test

    NASA Technical Reports Server (NTRS)

    Thiele, H. M.

    1984-01-01

    Development and construction of three 50 m rotor blades for a 3 MW wind turbine are described. A hybrid concept was chosen, i.e., a load carrying inflexible steel spar and a glass fiber reinforced plastic skin. A test blade was constructed and static loading tests, dynamic vibration tests and fatigue tests on critical welds as well as at the connection between spar and blade skin were performed. All test results show good accordance with calculated values, and were taken into consideration during the construction of two rotor blades.

  4. Propeller blade retention system

    NASA Technical Reports Server (NTRS)

    Elston, III, Sidney B. (Inventor); Simon, III, Victor H. (Inventor); Tseng, Wu-Yang (Inventor); Butler, Lawrence (Inventor)

    1993-01-01

    The invention concerns the mounting of propeller blades to a ring-shaped rotor. The blades are of the variable pitch type, and the shank of each blade extends through a respective hole in the rotor. Each hole contains an annular shelf which is fastened to the wall of the hole and surrounds each shank. Each shank bears a pair of bearing races which sandwich the annular shelf in order to connect the blade to the rotor. Bearing rollers are positioned between the annular shelf and the bearing races.

  5. Microtextured Surfaces for Turbine Blade Impingement Cooling

    NASA Technical Reports Server (NTRS)

    Fryer, Jack

    2014-01-01

    Gas turbine engine technology is constantly challenged to operate at higher combustor outlet temperatures. In a modern gas turbine engine, these temperatures can exceed the blade and disk material limits by 600 F or more, necessitating both internal and film cooling schemes in addition to the use of thermal barrier coatings. Internal convective cooling is inadequate in many blade locations, and both internal and film cooling approaches can lead to significant performance penalties in the engine. Micro Cooling Concepts, Inc., has developed a turbine blade cooling concept that provides enhanced internal impingement cooling effectiveness via the use of microstructured impingement surfaces. These surfaces significantly increase the cooling capability of the impinging flow, as compared to a conventional untextured surface. This approach can be combined with microchannel cooling and external film cooling to tailor the cooling capability per the external heating profile. The cooling system then can be optimized to minimize impact on engine performance.

  6. Application of HOST technology to the SSME HPFTP blade

    NASA Technical Reports Server (NTRS)

    Mcknight, R. L.; Cook, T. S.; Bechtel, G. S.; Huang, H. T.

    1989-01-01

    The development of turbine blade analysis tools as they moved from research contracts under the NASA HOST (Hot Section Technology) program to a PC-based system for preliminary design and to use in evaluating the SSME HPFTP (Space Shuttle Main Engine High Pressure Fuel Turbo Pump) blade is discussed. The heat transfer and structural analysis of the blade, the development of a data base for constitutive modeling of the blade materials, including coatings, and the use of advanced nonlinear finite element methods are addressed.

  7. Structural fatigue test results for large wind turbine blade sections

    NASA Technical Reports Server (NTRS)

    Faddoul, J. R.; Sullivan, T. L.

    1982-01-01

    In order to provide quantitative information on the operating life capabilities of wind turbine rotor blade concepts for root-end load transfer, a series of cantilever beam fatigue tests was conducted. Fatigue tests were conducted on a laminated wood blade with bonded steel studs, a low cost steel spar (utility pole) with a welded flange, a utility pole with additional root-end thickness provided by a swaged collar, fiberglass spars with both bonded and nonbonded fittings, and, finally, an aluminum blade with a bolted steel fitting (Lockheed Mod-0 blade). Photographs, data, and conclusions for each of these tests are presented. In addition, the aluminum blade test results are compared to field failure information; these results provide evidence that the cantilever beam type of fatigue test is a satisfactory method for obtaining qualitative data on blade life expectancy and for identifying structurally underdesigned areas (hot spots).

  8. Measurement of Rotorcraft Blade Deformation using Projection Moire Interferometry

    NASA Technical Reports Server (NTRS)

    Fleming, Gary A.; Gorton, Susan Althoff

    1998-01-01

    Projection Moire Interferometry (PMI) has been used to obtain near instantaneous, quantitative blade deformation measurements of a generic rotorcraft model at several test conditions. These laser-based measurements provide quantitative, whole field, dynamic blade deformation profiles conditionally sampled as a function of rotor azimuth. The instantaneous nature of the measurements permits computation of the mean and unsteady blade deformation, blade bending, and twist. The PMI method is presented, and the image processing steps required to obtain quantitative deformation profiles from PMI interferograms are described. Experimental results are provided which show blade bending, twist, and unsteady motion. This initial proof-of-concept test has demonstrated the capability of PMI to acquire accurate, full field rotorcraft blade deformation data.

  9. An aerodynamic study on flexed blades for VAWT applications

    NASA Astrophysics Data System (ADS)

    Micallef, Daniel; Farrugia, Russell; Sant, Tonio; Mollicone, Pierluigi

    2014-12-01

    There is renewed interest in aerodynamics research of VAWT rotors. Lift type, Darrieus designs sometimes use flexed blades to have an 'egg-beater shape' with an optimum Troposkien geometry to minimize the structural stress on the blades. While straight bladed VAWTs have been investigated in depth through both measurements and numerical modelling, the aerodynamics of flexed blades has not been researched with the same level of detail. Two major effects may have a substantial impact on blade performance. First, flexing at the equator causes relatively strong trailing vorticity to be released. Secondly, the blade performance at each station along the blade is influenced by self-induced velocities due to bound vorticity. The latter is not present in a straight bladed configuration. The aim of this research is to investigate these effects in relation to an innovative 4kW wind turbine concept being developed in collaboration with industry known as a self-adjusting VAWT (or SATVAWT). The approach used in this study is based on experimental and numerical work. A lifting line free-wake vortex model was developed. Wind tunnel power and hot-wire velocity measurements were performed on a scaled down, 60cm high, three bladed model in a closed wind tunnel. Results show a substantial axial wake induction at the equator resulting in a lower power generation at this position. This induction increases with increasing degree of flexure. The self-induced velocities caused by blade bound vorticity at a particular station was found to be relatively small.

  10. Technology Alignment and Portfolio Prioritization (TAPP): Advanced Methods in Strategic Analysis, Technology Forecasting and Long Term Planning for Human Exploration and Operations, Advanced Exploration Systems and Advanced Concepts

    NASA Technical Reports Server (NTRS)

    Funaro, Gregory V.; Alexander, Reginald A.

    2015-01-01

    The Advanced Concepts Office (ACO) at NASA, Marshall Space Flight Center is expanding its current technology assessment methodologies. ACO is developing a framework called TAPP that uses a variety of methods, such as association mining and rule learning from data mining, structure development using a Technological Innovation System (TIS), and social network modeling to measure structural relationships. The role of ACO is to 1) produce a broad spectrum of ideas and alternatives for a variety of NASA's missions, 2) determine mission architecture feasibility and appropriateness to NASA's strategic plans, and 3) define a project in enough detail to establish an initial baseline capable of meeting mission objectives ACO's role supports the decision­-making process associated with the maturation of concepts for traveling through, living in, and understanding space. ACO performs concept studies and technology assessments to determine the degree of alignment between mission objectives and new technologies. The first step in technology assessment is to identify the current technology maturity in terms of a technology readiness level (TRL). The second step is to determine the difficulty associated with advancing a technology from one state to the next state. NASA has used TRLs since 1970 and ACO formalized them in 1995. The DoD, ESA, Oil & Gas, and DoE have adopted TRLs as a means to assess technology maturity. However, "with the emergence of more complex systems and system of systems, it has been increasingly recognized that TRL assessments have limitations, especially when considering [the] integration of complex systems." When performing the second step in a technology assessment, NASA requires that an Advancement Degree of Difficulty (AD2) method be utilized. NASA has used and developed or used a variety of methods to perform this step: Expert Opinion or Delphi Approach, Value Engineering or Value Stream, Analytical Hierarchy Process (AHP), Technique for the Order of

  11. Final Project Report "Advanced Concept Exploration For Fast Ignition Science Program"

    SciTech Connect

    STEPHENS, Richard B.; McLEAN, Harry M.; THEOBALD, Wolfgang; AKLI, Kramer; BEG, Farhat N.; SENTOKU, Yasuiko; SCHUMACHER, Douglas; WEI, Mingsheng S.

    2014-01-31

    The Fast Ignition (FI) Concept for Inertial Confinement Fusion has the potential to provide a significant advance in the technical attractiveness of Inertial Fusion Energy (IFE) reactors. FI differs from conventional “central hot spot” (CHS) target ignition by decoupling compression from heating: using the laser (or heavy ion beam or Z pinch) drive pulse (10’s of ns) to create a dense fuel and a second, much shorter (~10 ps) high intensity pulse to ignite a small region of it. There are two major physics issues concerning this concept; controlling the laser-induced generation of large electron currents and their propagation through high density plasmas. This project has addressed these two significant scientific issues in Relativistic High Energy Density (RHED) physics. Learning to control relativistic laser matter interaction (and the limits and potential thereof) will enable a wide range of applications. While these physics issues are of specific interest to inertial fusion energy science, they are also important for a wide range of other HED phenomena, including high energy ion beam generation, isochoric heating of materials, and the development of high brightness x-ray sources. Generating, controlling, and understanding the extreme conditions needed to advance this science has proved to be challenging: Our studies have pushed the boundaries of physics understanding and are at the very limits of experimental, diagnostic, and simulation capabilities in high energy density laboratory physics (HEDLP). Our research strategy has been based on pursuing the fundamental physics underlying the Fast Ignition (FI) concept. We have performed comprehensive study of electron generation and transport in fast-ignition targets with experiments, theory, and numerical modeling. A major issue is that the electrons produced in these experiments cannot be measured directly—only effects due to their transport. We focused mainly on x-ray continuum photons from bremsstrahlung

  12. Fabrication of composite propfan blades for a cruise missile wind tunnel model

    NASA Technical Reports Server (NTRS)

    Fite, E. Brian

    1993-01-01

    This report outlines the procedures that were employed in fabricating prototype graphite-epoxy composite prop fan blades. These blades were used in wind tunnel tests that investigated prop fan propulsion system interactions with a missile airframe in order to study the feasibility of an advanced-technology-propfan-propelled missile. Major phases of the blade fabrication presented include machining of the master blade, mold fabrication, ply cutting and assembly, blade curing, and quality assurance. Specifically, four separate designs were fabricated, 18 blades of each geometry, using the same fabrication technique for each design.

  13. Proceedings of the International Symposium on Dynamics of Fluids in Fractured Rocks: Concepts and Recent Advances

    SciTech Connect

    Faybishenko, B.

    1999-02-01

    This publication contains extended abstracts of papers presented at the International Symposium ''Dynamics of Fluids in Fractured Rocks: Concepts and Recent Advances'' held at Ernest Orlando Lawrence Berkeley National Laboratory on February 10-12, 1999. This Symposium is organized in Honor of the 80th Birthday of Paul A. Witherspoon, who initiated some of the early investigations on flow and transport in fractured rocks at the University of California, Berkeley, and at Lawrence Berkeley National Laboratory. He is a key figure in the development of basic concepts, modeling, and field measurements of fluid flow and contaminant transport in fractured rock systems. The technical problems of assessing fluid flow, radionuclide transport, site characterization, modeling, and performance assessment in fractured rocks remain the most challenging aspects of subsurface flow and transport investigations. An understanding of these important aspects of hydrogeology is needed to assess disposal of nu clear wastes, development of geothermal resources, production of oil and gas resources, and remediation of contaminated sites. These Proceedings of more than 100 papers from 12 countries discuss recent scientific and practical developments and the status of our understanding of fluid flow and radionuclide transport in fractured rocks. The main topics of the papers are: Theoretical studies of fluid flow in fractured rocks; Multi-phase flow and reactive chemical transport in fractured rocks; Fracture/matrix interactions; Hydrogeological and transport testing; Fracture flow models; Vadose zone studies; Isotopic studies of flow in fractured systems; Fractures in geothermal systems; Remediation and colloid transport in fractured systems; and Nuclear waste disposal in fractured rocks.

  14. Organization of the 16th Advanced Accelerator Concepts (AAC) Workshop by Stanford University

    SciTech Connect

    Huang, Zhirong; Hogan, Mark

    2015-09-30

    Essentially all we know today and will learn in the future about the fundamental nature of matter is derived from probing it with directed beams of particles such as electrons, protons, neutrons, heavy ions, and photons. The resulting ability to “see” the building blocks of matter has had an immense impact on society and our standard of living. Over the last century, particle accelerators have changed the way we look at nature and the universe we live in and have become an integral part of the Nation’s technical infrastructure. Today, particle accelerators are essential tools of modern science and technology. The cost and capabilities of accelerators would be greatly enhanced by breakthroughs in acceleration methods and technology. For the last 32 years, the Advanced Accelerator Concepts (AAC) Workshop has acted as the focal point for discussion and development of the most promising acceleration physics and technology. It is a particularly effective forum where the discussion is leveraged and promoted by the unique and demanding feature of the AAC Workshop: the working group structure, in which participants are asked to consider their contributions in terms of even larger problems to be solved. The 16th Advanced Accelerator Concepts (AAC2014) Workshop was organized by Stanford University from July 13 - 18, 2014 at the Dolce Hays Mansion in San Jose, California. The conference had a record 282 attendees including 62 students. Attendees came from 11 countries representing 66 different institutions. The workshop format consisted of plenary sessions in the morning with topical leaders from around the world presenting the latest breakthroughs to the entire workshop. In the late morning and afternoons attendees broke out into eight different working groups for more detailed presentations and discussions that were summarized on the final day of the workshop. In addition, there were student tutorial presentations on two afternoons to provide in depth education and

  15. Parabolic Flight Investigation for Advanced Exercise Concept Hardware Hybrid Ultimate Lifting Kit (HULK)

    NASA Technical Reports Server (NTRS)

    Weaver, A. S.; Funk, J. H.; Funk, N. W.; Sheehan, C. C.; Humphreys, B. T.; Perusek, G. P.

    2015-01-01

    Long-duration space flight poses many hazards to the health of the crew. Among those hazards is the physiological deconditioning of the musculoskeletal and cardiovascular systems due to prolonged exposure to microgravity. To combat this erosion of physical condition space flight may take on the crew, the Human Research Program (HRP) is charged with developing Advanced Exercise Concepts to maintain astronaut health and fitness during long-term missions, while keeping device mass, power, and volume to a minimum. The goal of this effort is to preserve the physical capability of the crew to perform mission critical tasks in transit and during planetary surface operations. The HULK is a pneumatic-based exercise system, which provides both resistive and aerobic modes to protect against human deconditioning in microgravity. Its design targeted the International Space Station (ISS) Advanced Resistive Exercise Device (ARED) high level performance characteristics and provides up to 600 foot pounds resitive loading with the capability to allow for eccentric to concentric (E:C) ratios of higher than 1:1 through a DC motor assist component. The device's rowing mode allows for high cadence aerobic activity. The HULK parabolic flight campaign, conducted through the NASA Flight Opportunities Program at Ellington Field, resulted in the creation of device specific data sets including low fidelity motion capture, accelerometry and both inline and ground reaction forces. These data provide a critical link in understanding how to vibration isolate the device in both ISS and space transit applications. Secondarily, the study of human exercise and associated body kinematics in microgravity allows for more complete understanding of human to machine interface designs to allow for maximum functionality of the device in microgravity.

  16. Revolutionary Concepts for Helicopter Noise Reduction: SILENT Program

    NASA Technical Reports Server (NTRS)

    Edwards, Bryan; Cox, Charles; Booth, Earl R., Jr. (Technical Monitor)

    2002-01-01

    As part of a NASA initiative to reduce helicopter main rotor noise, a Phase 1 study has been performed of candidate noise reduction concepts. Both conventional and novel design technologies have been analyzed that reduce the community impact of helicopter operations. In this study the noise reduction potential and design implications are assessed for conventional means of noise reduction, e.g., tip speed reduction, tip shapes and airfoil tailoring, and for two innovative design concepts: modulated blade spacing and x-force control. Main rotor designs that incorporate modulated blade spacing are shown to have reduced peak noise levels in most flight operations. X-force control alters the helicopter's force balance whereby the miss distance between main rotor blades and shed vortices can be controlled. This control provides a high potential to mitigate BVI noise radiation. Each concept is evaluated using best practice design and analysis methods, achieving the study's aim to significantly reduce noise with minimal performance degradation and no vibration increase. It is concluded that a SILENT main rotor design, incorporating the modulated blade spacing concept, offers significantly reduced noise levels and the potential of a breakthrough in how a helicopter's sound is perceived and judged. The SILENT rotor represents a definite advancement in the state-of-the-art and is selected as the design concept for demonstration in Phase 2. A Phase 2 Implementation Plan is developed for whirl cage and wind tunnel evaluations of a scaled model SILENT rotor.

  17. Advanced Concepts for Pressure-Channel Reactors: Modularity, Performance and Safety

    NASA Astrophysics Data System (ADS)

    Duffey, Romney B.; Pioro, Igor L.; Kuran, Sermet

    Based on an analysis of the development of advanced concepts for pressure-tube reactor technology, we adapt and adopt the pressure-tube reactor advantage of modularity, so that the subdivided core has the potential for optimization of the core, safety, fuel cycle and thermal performance independently, while retaining passive safety features. In addition, by adopting supercritical water-cooling, the logical developments from existing supercritical turbine technology and “steam” systems can be utilized. Supercritical and ultra-supercritical boilers and turbines have been operating for some time in coal-fired power plants. Using coolant outlet temperatures of about 625°C achieves operating plant thermal efficiencies in the order of 45-48%, using a direct turbine cycle. In addition, by using reheat channels, the plant has the potential to produce low-cost process heat, in amounts that are customer and market dependent. The use of reheat systems further increases the overall thermal efficiency to 55% and beyond. With the flexibility of a range of plant sizes suitable for both small (400 MWe) and large (1400 MWe) electric grids, and the ability for co-generation of electric power, process heat, and hydrogen, the concept is competitive. The choice of core power, reheat channel number and exit temperature are all set by customer and materials requirements. The pressure channel is a key technology that is needed to make use of supercritical water (SCW) in CANDU®1 reactors feasible. By optimizing the fuel bundle and fuel channel, convection and conduction assure heat removal using passive-moderator cooling. Potential for severe core damage can be almost eliminated, even without the necessity of activating the emergency-cooling systems. The small size of containment structure lends itself to a small footprint, impacts economics and building techniques. Design features related to Canadian concepts are discussed in this paper. The main conclusion is that development of

  18. Fan blade protection system

    NASA Technical Reports Server (NTRS)

    Hermans, Thomas C. (Inventor); Wakeman, Thomas G. (Inventor); Hauser, Ambrose A. (Inventor)

    1993-01-01

    In one type of aircraft propulsion system, propeller blades are mounted on a ring which surrounds a turbine. An annular space exists between the turbine and the ring. If a propeller blade should break free, the unbalanced centrifugal load tends to deform the ring. The invention reduces the deformation, as by locating spacers between the turbine and the ring.

  19. Design and evaluation of low cost blades for large wind driven generating systems

    NASA Technical Reports Server (NTRS)

    Eggert, W. S.

    1982-01-01

    The development and evaluation of a low cost blade concept based on the NASA-Lewis specifications is discussed. A blade structure was designed and construction methods and materials were selected. Complete blade tooling concepts, various technical and economic analysis, and evaluations of the blade design were performed. A comprehensive fatigue test program was conducted to provide data and to verify the design. A test specimen of the spar assembly, including the root end attachment, was fabricated. This is a full-scale specimen of the root end configuration, 20 ft long. A blade design for the Mod '0' system was completed.

  20. Feasibility study of pultruded blades for wind turbine rotors

    SciTech Connect

    Migliore, P.G.; Cheney, M.C.

    2000-02-28

    In work performed under subcontract to the National Renewable Energy Laboratory (NREL), a preliminary design study and proof-of-concept field test were conducted to evaluate the feasibility of using pultruded blades for wind turbine rotors. A 400 kW turbine was selected for the design study, and a scaled 80 kW rotor was fabricated and tested as a demonstration of the concept. To examine the feasibility of pultruded blades, several issues were addressed, including power performance, tower strikes, yaw stability, stall flutter, fatigue, and rotor cost. Results showed that with proper design, rotors using pultruded blades demonstrate acceptable fatigue life and stable yaw behavior without tower strikes. Furthermore, blades using this technology may be manufactured for approximately half the cost of conventional blades. Field tests of the scaled rotor provided experimental data on power performance and loads while verifying stable yaw operation.

  1. Composite wind turbine blades

    NASA Astrophysics Data System (ADS)

    Ong, Cheng-Huat

    Researchers in wind energy industry are constantly moving forward to develop higher efficiency wind turbine. One major component for wind turbine design is to have cost effective wind turbine blades. In addition to correct aerodynamic shape and blade geometry, blade performance can be enhanced further through aero-elastic tailoring design and material selections. An analytical tool for blade design has been improved and validated. This analytical tool is utilized to resolve issues related to elastic tailoring design. The investigation looks into two major issues related to the design and fabrication of a bend-twist-coupled blade. Various design parameters for a blade such as materials, laminate lay-up, skin thickness, ply orientation, internal spar, etc. have been examined for designing a bend-twist-coupled blade. The parametric study indicates that the critical design parameters are the ply material, the ply orientation, and the volume fraction ratio between the anisotropic layers and orthotropic layers. To produce a blade having the bend-twist coupling characteristics, the fiber lay-ups at the top and bottom skins of the blade must have a "mirror" lay-up in relation to the middle plane of the blade. Such lay-up causes fiber discontinuation at the seam. The joint design at the seam is one major consideration in fabricating a truly anisotropic blade. A new joint design was proposed and tensile failure tests were carried out for both the old and new joint designs. The tests investigated the effects of different types of joint designs, the laminate lay-up at the joints, and the stacking sequence of the joint retention strength. A major component of a wind turbine blade, D-spar, was designed to maximum coupling. Two D-spars were then fabricated using the new joint design; one of them was subjected to both static and modal testings. Traditionally, wind turbine blades are made of low cost glass material; however, carbon fibers are proposed as alternative material. Our

  2. Turbine blade platform seal

    DOEpatents

    Zagar, Thomas W.; Schiavo, Anthony L.

    2001-01-01

    A rotating blade group 90 for a turbo-machine having an improved device for sealing the gap 110 between the edges 112,114 of adjacent blade platforms 96,104. The gap 110 between adjacent blades 92,100 is sealed by a seal pin 20 its central portion 110 and by a seal plate 58,60 at each of the front 54 and rear 56 portions. The seal plates 58,60 are inserted into corresponding grooves 62,64 formed in the adjacent edges 112,114 of adjoining blades 92,100 and held in place by end plates 40,42. The end of the seal plates 58,60 may be chamfered 78,80 to improve the seal against the end plate 40,42. The seal pin 20 provides the required damping between the blades 92,100 and the seal plates 58,60 provide improved sealing effectiveness.

  3. Ceramic blade attachment system

    DOEpatents

    Shaffer, James E.

    1995-01-01

    A turbine blade having a preestablished rate of thermal expansion is attached to a turbine wheel having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade. The turbine blade has a root portion having a first groove and a second groove therein. The turbine wheel includes a plurality of openings in which the turbine blade is positioned. Each of the openings has a first groove and a second groove therein. The space or void formed between the first grooves and the second grooves has a plurality of spherical balls positioned therein. The plurality of spherical balls has a preestablished rate of thermal expansion being equal to the preestablished rate of thermal expansion of the turbine blade.

  4. Ceramic blade attachment system

    DOEpatents

    Shaffer, J.E.

    1995-01-10

    A turbine blade having a preestablished rate of thermal expansion is attached to a turbine wheel having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade. The turbine blade has a root portion having a first groove and a second groove therein. The turbine wheel includes a plurality of openings in which the turbine blade is positioned. Each of the openings has a first groove and a second groove therein. The space or void formed between the first grooves and the second grooves has a plurality of spherical balls positioned therein. The plurality of spherical balls has a preestablished rate of thermal expansion being equal to the preestablished rate of thermal expansion of the turbine blade. 4 figures.

  5. Innovative concept for an advanced hadron facility based on a 2 GeV H/sup -/ linac

    SciTech Connect

    Thiessen, H.A.

    1987-01-01

    This report presents parameters for an innovative new concept for the design of an advanced hadron facility. We propose combining a cold neutron source with a kaon factory. We also discuss the possibility of a shared target for neutron and neutrino experiments. An initial cost estimate is presented.

  6. Advanced Concept Studies for Supersonic Commercial Transports Entering Service in the 2018 to 2020 Period

    NASA Technical Reports Server (NTRS)

    Morgenstern, John; Norstrud, Nicole; Sokhey, Jack; Martens, Steve; Alonso, Juan J.

    2013-01-01

    Lockheed Martin Aeronautics Company (LM), working in conjunction with General Electric Global Research (GE GR), Rolls-Royce Liberty Works (RRLW), and Stanford University, herein presents results from the "N+2 Supersonic Validations" contract s initial 22 month phase, addressing the NASA solicitation "Advanced Concept Studies for Supersonic Commercial Transports Entering Service in the 2018 to 2020 Period." This report version adds documentation of an additional three month low boom test task. The key technical objective of this effort was to validate integrated airframe and propulsion technologies and design methodologies. These capabilities aspired to produce a viable supersonic vehicle design with environmental and performance characteristics. Supersonic testing of both airframe and propulsion technologies (including LM3: 97-023 low boom testing and April-June nozzle acoustic testing) verified LM s supersonic low-boom design methodologies and both GE and RRLW's nozzle technologies for future implementation. The N+2 program is aligned with NASA s Supersonic Project and is focused on providing system-level solutions capable of overcoming the environmental and performance/efficiency barriers to practical supersonic flight. NASA proposed "Initial Environmental Targets and Performance Goals for Future Supersonic Civil Aircraft". The LM N+2 studies are built upon LM s prior N+3 100 passenger design studies. The LM N+2 program addresses low boom design and methodology validations with wind tunnel testing, performance and efficiency goals with system level analysis, and low noise validations with two nozzle (GE and RRLW) acoustic tests.

  7. A review of design concepts for the Advanced Fluids Module (AFM) project

    NASA Technical Reports Server (NTRS)

    Hill, Myron E.; Tschen, Peter S.

    1993-01-01

    This paper reviews preliminary fluid module design concepts for the Advanced Fluids Module (AFM) project. The objective of this effort is to provide a facility that can handle a wide variety of fluids experiments. Sample science requirements were written and conceptual designs were subsequently generated during the last year. Experiments from the following fluid physics subject areas were used as conceptual design drivers: static and dynamic interfacial phenomena; bubble/droplet thermocapillary migration; surface tension convection and instabilities; thermal/solutal convection; pool boiling; and multiphase flow. After the conceptual designs were completed, the next phase attempted to combine experiments capabilities into a multipurpose, multiuser apparatus configured for the Space Station Freedom. It was found that all the fluid subject areas considered could be accommodated by three basic types of fluids modules. These modules are the Static Fluid Cell Module, the Dynamic Fluid Cell Module, and the Multiphase Flow Module. Descriptions of these preliminary modules designs and their particular sub-systems (e.g., fluid and thermal systems) are discussed. These designs will be refined as the nature of the flight program becomes clearer over the next six to twelve months.

  8. Real-time manned simulation of advanced terminal area guidance concepts for short-haul operations

    NASA Technical Reports Server (NTRS)

    Tobias, L.; Obrien, P. J.

    1977-01-01

    A real-time simulation was conducted of three-dimensional area navigation and four-dimensional area navigation equipped (STOL) aircraft operating in a high-density terminal area traffic environment. The objectives were to examine the effects of 3D RNAV and 4D RNAV equipped aircraft on the terminal area traffic efficiency, and to examine the performance of an air traffic control system concept and associated controller display proposed for use with advanced RNAV systems. Three types of STOL aircraft were simulated each with different performance capabilities. System performance was measured in both the 4D mode and in a 3D mode; the 3D mode, used as a baseline, was simply the 4D mode less any time specification. The results show that communications workload in the 4D mode was reduced by about 35 percent compared to the 3D, while 35 percent more traffic was handled with the 4D. Aircraft holding time in the 4D mode was only 30 percent of that required in the 3D mode. In addition, the orderliness of traffic was improved significantly in the 4D mode.

  9. Lessons learned from U.S. Department of Defense 911-Bio Advanced Concept Technology Demonstrations.

    SciTech Connect

    Baldwin, T.; Gasper, W.; Lacher, L.; Newsom, D.; Yantosik, G.

    1999-07-06

    The US Department of Defense (DoD), in cooperation with other federal agencies, has taken many initiatives to improve its ability to support civilian response to a domestic biological terrorism incident. This paper discusses one initiative, the 911-Bio Advanced Concept Technology Demonstrations (ACTDs), conducted by the Office of the Secretary of Defense during 1997 to better understand: (1) the capability of newly developed chemical and biological collection and identification technologies in a field environment; (2) the ability of specialized DoD response teams to use these new technologies within the structure of cooperating DoD and civilian consequence management organizations; and (3) the adequacy of current modeling tools for predicting the dispersal of biological hazards. This paper discusses the experience of the ACTDs from the civilian community support perspective. The 911-Bio ACTD project provided a valuable opportunity for DoD and civilian officials to learn how they should use their combined capabilities to manage the aftermath of a domestic biological terrorism incident.

  10. Advanced life support control/monitor instrumentation concepts for flight application

    NASA Technical Reports Server (NTRS)

    Heppner, D. B.; Dahlhausen, M. J.; Fell, R. B.

    1986-01-01

    Development of regenerative Environmental Control/Life Support Systems requires instrumentation characteristics which evolve with successive development phases. As the development phase moves toward flight hardware, the system availability becomes an important design aspect which requires high reliability and maintainability. This program was directed toward instrumentation designs which incorporate features compatible with anticipated flight requirements. The first task consisted of the design, fabrication and test of a Performance Diagnostic Unit. In interfacing with a subsystem's instrumentation, the Performance Diagnostic Unit is capable of determining faulty operation and components within a subsystem, perform on-line diagnostics of what maintenance is needed and accept historical status on subsystem performance as such information is retained in the memory of a subsystem's computerized controller. The second focus was development and demonstration of analog signal conditioning concepts which reduce the weight, power, volume, cost and maintenance and improve the reliability of this key assembly of advanced life support instrumentation. The approach was to develop a generic set of signal conditioning elements or cards which can be configured to fit various subsystems. Four generic sensor signal conditioning cards were identified as being required to handle more than 90 percent of the sensors encountered in life support systems. Under company funding, these were detail designed, built and successfully tested.

  11. Concepts for 3D print productivity systems with advanced DLP photoheads

    NASA Astrophysics Data System (ADS)

    Jacobsen, Alfred; Jorgensen, Trond; Tafjord, Øyvind; Kirkhorn, Endre

    2015-03-01

    Direct Imaging with DLP® Photoheads is becoming an established technology in productivity systems for PCB Lithography and similar applications. Scrolling technology is used to expose large areas and is enabling highest levels of productivity and efficiency, while maintaining full flexibility of direct imaging concepts. Specific features such as SPX (subpixelation) and PPC (pixel power control) technologies have further enhanced resolution of printed structures, as well as precision and uniformity of the exposure across the entire field. 3D print systems with photosensitive resins can conceptually be seen as an extension of 2D Direct Imaging systems into the third dimension. The scrolling technique then allows to enlarge the build area by freely multiplying the photohead's static build area with native pixel pitch in both, x and y dimensions. In addition, SPX technology in 3D print systems would enable 2 different advanced options. Either it offers improved (reduced) edge roughness of structures, by fine pitching the native pixel pitch. Or a larger native pixel pitch can be chosen, still providing the same fine pitched edge roughness and surface finish as a native system with proportionally smaller build area.

  12. Advances and New Concepts in Alcohol-Induced Organelle Stress, Unfolded Protein Responses and Organ Damage

    PubMed Central

    Ji, Cheng

    2015-01-01

    Alcohol is a simple and consumable biomolecule yet its excessive consumption disturbs numerous biological pathways damaging nearly all organs of the human body. One of the essential biological processes affected by the harmful effects of alcohol is proteostasis, which regulates the balance between biogenesis and turnover of proteins within and outside the cell. A significant amount of published evidence indicates that alcohol and its metabolites directly or indirectly interfere with protein homeostasis in the endoplasmic reticulum (ER) causing an accumulation of unfolded or misfolded proteins, which triggers the unfolded protein response (UPR) leading to either restoration of homeostasis or cell death, inflammation and other pathologies under severe and chronic alcohol conditions. The UPR senses the abnormal protein accumulation and activates transcription factors that regulate nuclear transcription of genes related to ER function. Similarly, this kind of protein stress response can occur in other cellular organelles, which is an evolving field of interest. Here, I review recent advances in the alcohol-induced ER stress response as well as discuss new concepts on alcohol-induced mitochondrial, Golgi and lysosomal stress responses and injuries. PMID:26047032

  13. Predicted reliability of aerospace electronics: Application of two advanced probabilistic concepts

    NASA Astrophysics Data System (ADS)

    Suhir, E.

    Two advanced probabilistic design-for-reliability (PDfR) concepts are addressed and discussed in application to the prediction, quantification and assurance of the aerospace electronics reliability: 1) Boltzmann-Arrhenius-Zhurkov (BAZ) model, which is an extension of the currently widely used Arrhenius model and, in combination with the exponential law of reliability, enables one to obtain a simple, easy-to-use and physically meaningful formula for the evaluation of the probability of failure (PoF) of a material or a device after the given time in operation at the given temperature and under the given stress (not necessarily mechanical), and 2) Extreme Value Distribution (EVD) technique that can be used to assess the number of repetitive loadings that result in the material/device degradation and eventually lead to its failure by closing, in a step-wise fashion, the gap between the bearing capacity (stress-free activation energy) of the material or the device and the demand (loading). It is shown that the material degradation (aging, damage accumulation, flaw propagation, etc.) can be viewed, when BAZ model is considered, as a Markovian process, and that the BAZ model can be obtained as the ultimate steady-state solution to the well-known Fokker-Planck equation in the theory of Markovian processes. It is shown also that the BAZ model addresses the worst, but a reasonably conservative, situation. It is suggested therefore that the transient period preceding the condition addressed by the steady-state BAZ model need not be accounted for in engineering evaluations. However, when there is an interest in understanding the transient degradation process, the obtained solution to the Fokker-Planck equation can be used for this purpose. As to the EVD concept, it attributes the degradation process to the accumulation of damages caused by a train of repetitive high-level loadings, while loadings of levels that are considerably lower than their extreme values do not contribute

  14. A System Concept for the Advanced Post-TRMM Rainfall Profiling Radars

    NASA Technical Reports Server (NTRS)

    Im, Eastwood; Smith, Eric A.

    1998-01-01

    ultimate goal. The Precipitation Radar (PR) aboard the TRMM satellite is the first ever spaceborne radar dedicated to three-dimensional, global precipitation measurements over the tropics and the subtropics, as well as the detailed synopsis of a wide range of tropical rain storm systems. In only twelve months since launch, the PR, together with other science instruments abroad the satellite have already provided unprecedented insights into the rainfall systems. It is anticipated the a lot more exciting and important rain observations would be made by TRMM throughout its mission duration. While TRMM has provided invaluable data to the user community, it is only the first step towards advancing our knowledge on rain processes and its contributions to climate variability. It is envisioned that a TRMM follow-on mission is needed in such a way to capitalize on the pioneering information provided by TRMM, and its instrument capability must be extended beyond TRMM in such a way to fully address the key science questions from microphysical to climatic time scale. In fact, a number of new and innovative mission concepts have recently put forth for this purpose. Almost all of these new concepts have suggested the utility of a more advanced, high-resolution, Doppler-enabled, vertical profiling radar that can provide multi-parameter observations of precipitation. In this paper, a system concept for a second- gene ration precipitation radar (PR-2) which addresses the above requirements will be described.

  15. Energy efficient engine high-pressure turbine single crystal vane and blade fabrication technology report

    NASA Technical Reports Server (NTRS)

    Giamei, A. F.; Salkeld, R. W.; Hayes, C. W.

    1981-01-01

    The objective of the High-Pressure Turbine Fabrication Program was to demonstrate the application and feasibility of Pratt & Whitney Aircraft-developed two-piece, single crystal casting and bonding technology on the turbine blade and vane configurations required for the high-pressure turbine in the Energy Efficient Engine. During the first phase of the program, casting feasibility was demonstrated. Several blade and vane halves were made for the bonding trials, plus solid blades and vanes were successfully cast for materials evaluation tests. Specimens exhibited the required microstructure and chemical composition. Bonding feasibility was demonstrated in the second phase of the effort. Bonding yields of 75 percent for the vane and 30 percent for the blade were achieved, and methods for improving these yield percentages were identified. A bond process was established for PWA 1480 single crystal material which incorporated a transient liquid phase interlayer. Bond properties were substantiated and sensitivities determined. Tooling die materials were identified, and an advanced differential thermal expansion tooling concept was incorporated into the bond process.

  16. Consilience and a Hierarchy of Species Concepts: Advances Toward Closure on the Species Puzzle

    PubMed Central

    Mayden, Richard L.

    1999-01-01

    Numerous concepts exist for biological species. This diversity of ideas derives from a number of sources ranging from investigative study of particular taxa and character sets to philosophical aptitude and world view to operationalism and nomenclatorial rules. While usually viewed as counterproductive, in reality these varied concepts can greatly enhance our efforts to discover and understand biological diversity. Moreover, this continued "turf war" and dilemma over species can be resolved if the various concepts are viewed in a hierarchical system and each evaluated for its inherent level of consilience. Under this paradigm a theoretically appropriate, highly consilient concept of species capable of colligating the abundant types of species diversity offers the best guidance for developing and employing secondary operational concepts for identifying diversity. Of all the concepts currently recognized, only the non-operational Evolutionary Species Concept corresponds to the requisite parameters and, therefore, should serve as the theoretical concept appropriate for the category Species. As operational concepts, the remaining ideas have been incompatible with one another in their ability to encompass species diversity because each has restrictive criteria as to what qualifies as a species. However, the operational concepts can complement one another and do serve a vital role under the Evolutionary Species Concept as fundamental tools necessary for discovering diversity compatible with the primary theoretical concept. Thus, the proposed hierarchical system of primary and secondary concepts promises both the most productive framework for mutual respect for varied concepts and the most efficient and effective means for revealing species diversity. PMID:19270881

  17. Inflow measurement made with a laser velocimeter on a helicopter model in forward flight. Volume 5: Tapered planform blades at an advance ratio of 0.23

    NASA Technical Reports Server (NTRS)

    Althoff, Susan L.; Elliott, Joe W.; Sailey, Richard H.

    1988-01-01

    An experimental investigation was conducted in the 14- by 22-Foot Subsonic tunnel at NASA Langley Research Center to measure the inflow into a scale model helicopter rotor in forward flight (mu sub inf = 0.23). The measurements were made with a two component Laser Velocimeter (LV) one chord above the plane formed by the path of the blade tips. A conditional sampling technique was employed to determine the position of the rotor at the time that each velocity measurement was made so that the azimuthal fluctuations in velocity could be determined. Measurements were made at a total of 168 separate locations in order to clearly define the inflow character. This data is presented without analysis. In order to increase the availability of the resulting data, both the mean and azimuthally dependenet values are included as part of this report on two 5.25 inch floppy disks in Microsoft Corporation MS-DOS format.

  18. Wind turbine blade construction

    SciTech Connect

    Basso, R.J.

    1988-03-01

    This patent describes a blade for the rotor of a wind turbine or the like having a root end mounted on the rotor and extending generally radially outwardly from the rotor out to a distal end comprising: (a) a cuff at the root end of the blade for mounting on the rotor, and having a generally cylindrical, radially outwardly directed collar; (b) a generally cylindrical reinforcing strut mounted generally coaxially to the collar, and extending radially outwardly from the rotor throughout a portion of the length of the blade; (c) a hollow spar coaxially mounted around the strut and extending substantially the full length of the blade; (d) an elongated, rigid aerodynamic skin defining the exterior, wind-encountering surfaces of the blade, and being mounted over and bonded to the strut and defining the distal end of the blade; (e) the reinforcing strut being of decreasing diameter toward the distal end of the blade; and (f) the reinforcing strut comprising telescoping tubes of graduated length with the larger diameter tubes being longer than the smaller diameter tubes.

  19. Highly reusable space transportation: Advanced concepts and the opening of the space frontier

    NASA Astrophysics Data System (ADS)

    Mankins, John C.

    2002-11-01

    Revolutionary changes in how cargo and people are transported into space are needed to enable the affordable development and exploration of space in the 21st century. Diverse efforts to achieve major, but incremental Earth-to-orbit (ETO) improvements in the relatively near term have been undertaken in recent years in the US, including the Department of Defense evolved expendable launch vehicle system development project. The NASA-industry reusable launch vehicle (RLV) program is addressing this challenge for the mid-term. The RLV program will validate the technology to enable industry to develop all-rocket reusable launch systems that can deliver payloads from the current Civil Needs Data Base in the 20,000-40,000 pounds class and smaller to low Earth orbit (LEO) at costs of approximately 1000-2000 per pound. This represents a factor of 5 (or more) reduction below existing launch services. This "next generation" improvement in launch capability is a vital element of the US National Space Transportation policy for current and planned government and commercial payloads. The longer-term challenge is also being addressed. During 1995-1997, NASA conducted the highly reusable space transportation (HRST) study project to address the longer-term challenge: how to achieve an additional factor of 10 reduction in launch costs—to approximately 100-200 per payload pound to LEO—thus enabling a revolutionary expansion of space activity and enterprise. The HRST study has identified a "grand strategy" for achieving these cost goals, based on pursuing a revolutionary advance in main propulsion architectures and technology for ETO systems to enable a dramatic improvements in subsystem operability. The HRST study has examined diverse approaches, including combination propulsion systems, combined cycle propulsion, launch assist systems, and revolutionary rocket propulsion. An integrated assessment has been conducted, including both the concepts defined as part of the study as well

  20. Liminality in cultural transition: applying ID-EA to advance a concept into theory-based practice.

    PubMed

    Baird, Martha B; Reed, Pamela G

    2015-01-01

    As global migration increases worldwide, nursing interventions are needed to address the effects of migration on health. The concept of liminality emerged as a pivotal concept in the situation-specific theory of well-being in refugee women experiencing cultural transition. As a relatively new concept in the discipline of nursing, liminality is explored using a method, called ID-EA, which we developed to advance a theoretical concept for application to nursing practice. Liminality in the context of cultural transition is further developed using the five steps of inquiry of the ID-EA method. The five steps are as follows: (1) inductive inquiry: qualitative research, (2) deductive inquiry: literature review, (3) synthesis of inductive and deductive inquiry, (4) evaluation inquiry, and (5) application-to-practice inquiry. The overall goal of this particular work was to develop situation-specific, theory-based interventions that facilitate cultural transitions for immigrants and refugees. PMID:25799694

  1. Analysis and Tests of Pultruded Blades for Wind Turbine Rotors

    SciTech Connect

    Cheney, M. C.; Olsen, T.; Quandt, G.; Archidiacono, P.

    1999-07-19

    PS Enterprises, Inc. investigated a flexible, downwind, free-yaw, five-blade rotor system employing pultruded blades. A rotor was designed, manufactured and tested in the field. A preliminary design study and proof of concept test were conducted to assess the feasibility of using pultruded blades for wind turbine rotors. A 400 kW turbine was selected for the design study and a scaled 80 kW rotor was fabricated and field tested as a demonstration of the concept. The design studies continued to support the premise that pultruded blades offer the potential for significant reductions in rotor weight and cost. The field test provided experimental performance and loads data that compared well with predictions using the FLEXDYNE aeroelastic analysis. The field test also demonstrated stable yaw behavior and the absence of stall flutter over the wind conditions tested. During the final year of the contract, several studies were conducted by a number of independent consultants to address specific technical issues related to pultruded blades that could impact the commercial viability of turbines using this technology. The issues included performance, tower strikes, yaw stability, stall flutter, fatigue, and costs. While the performance of straight pultruded blades was projected to suffer a penalty of about 13% over fully twisted and tapered blades, the study showed that an aerodynamic fairing over the inner 40% could recover 85% of that loss while still keeping the blade cost well below that of conventional blades. Other results of the study showed that with proper design, rotors using pultruded blades could operate without aeroelastic problems, have acceptable fatigue life, and cost less than half that of rotors employing conventionally manufactured blades.

  2. The Effects of Using Concept Mapping for Improving Advanced Level Biology Students' Lower- and Higher-Order Cognitive Skills

    NASA Astrophysics Data System (ADS)

    Bramwell-Lalor, Sharon; Rainford, Marcia

    2014-03-01

    This paper reports on teachers' use of concept mapping as an alternative assessment strategy in advanced level biology classes and its effects on students' cognitive skills on selected biology concepts. Using a mixed methods approach, the study employed a pre-test/post-test quasi-experimental design involving 156 students and 8 teachers from intact classes. A researcher-constructed Biology Cognitive Skills Test was used to collect the quantitative data. Qualitative data were collected through interviews and students' personal documents. The data showed that the participants utilized concept mapping in various ways and they described positive experiences while being engaged in its use. The main challenge cited by teachers was the limited time available for more consistent use. The results showed that the use of concept mapping in advanced level biology can lead to learning gains that exceed those achieved in classes where mainly traditional methods are used. The students in the concept mapping experimental groups performed significantly better than their peers in the control group on both the lower-order (F(1) = 21.508; p < .001) and higher-order (F(1) = 42.842, p < .001) cognitive items of the biology test. A mean effect size of .56 was calculated representing the contribution of treatment to the students' performance on the test items.

  3. Thermal-barrier-coated turbine blade study

    NASA Technical Reports Server (NTRS)

    Siemers, P. A.; Hillig, W. B.

    1981-01-01

    The effects of coating TBC on a CF6-50 stage 2 high-pressure turbine blade were analyzed with respect to changes in the mean bulk temperature, cooling air requirements, and high-cycle fatigue. Localized spallation was found to have a possible deleterious effect on low-cycle fatigue life. New blade design concepts were developed to take optimum advantage of TBCs. Process and material development work and rig evaluations were undertaken which identified the most promising combination as ZrO2 containing 8 w/o Y2O3 applied by air plasma spray onto a Ni22Cr-10Al-1Y bond layer. The bond layer was applied by a low-pressure, high-velocity plasma spray process onto the base alloy. During the initial startup cycles the blades experienced localized leading edge spallation caused by foreign objects.

  4. Blade attachment assembly

    DOEpatents

    Garcia-Crespo, Andres Jose; Delvaux, John McConnell; Miller, Diane Patricia

    2016-05-03

    An assembly and method for affixing a turbomachine rotor blade to a rotor wheel are disclosed. In an embodiment, an adaptor member is provided disposed between the blade and the rotor wheel, the adaptor member including an adaptor attachment slot that is complementary to the blade attachment member, and an adaptor attachment member that is complementary to the rotor wheel attachment slot. A coverplate is provided, having a coverplate attachment member that is complementary to the rotor wheel attachment slot, and a hook for engaging the adaptor member. When assembled, the coverplate member matingly engages with the adaptor member, and retains the blade in the adaptor member, and the assembly in the rotor wheel.

  5. Ceramic blade attachment system

    DOEpatents

    Boyd, Gary L.

    1994-01-01

    A turbine blade having a preestablished rate of thermal expansion is attached to a turbine wheel having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade. The turbine blade has a root portion having a pair of recessed portions thereon. The turbine wheel includes a plurality of openings in which the turbine blade is positioned. Each of the openings have a pair of grooves therein in which are positioned a pair of pins having a generally rectangular cross-section and a reaction surface thereon. A pair of cylindrical rollers interposed respective ones of the pair of reaction surfaces and the pair of recessed portions. The attachment system or turbine assembly provides an economical, reliable and effective attachment of a component having a preestablished rate of thermal expansion to a component having a greater preestablished rate of thermal expansion.

  6. Ceramic blade attachment system

    DOEpatents

    Boyd, G.L.

    1994-12-13

    A turbine blade having a preestablished rate of thermal expansion is attached to a turbine wheel having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade. The turbine blade has a root portion having a pair of recessed portions thereon. The turbine wheel includes a plurality of openings in which the turbine blade is positioned. Each of the openings have a pair of grooves therein in which are positioned a pair of pins having a generally rectangular cross-section and a reaction surface thereon. A pair of cylindrical rollers interposed respective ones of the pair of reaction surfaces and the pair of recessed portions. The attachment system or turbine assembly provides an economical, reliable and effective attachment of a component having a preestablished rate of thermal expansion to a component having a greater preestablished rate of thermal expansion. 3 figures.

  7. Advanced transportation system study: Manned launch vehicle concepts for two way transportation system payloads to LEO. Program cost estimates document

    NASA Technical Reports Server (NTRS)

    Duffy, James B.

    1993-01-01

    This report describes Rockwell International's cost analysis results of manned launch vehicle concepts for two way transportation system payloads to low earth orbit during the basic and option 1 period of performance for contract NAS8-39207, advanced transportation system studies. Vehicles analyzed include the space shuttle, personnel launch system (PLS) with advanced launch system (ALS) and national launch system (NLS) boosters, foreign launch vehicles, NLS-2 derived launch vehicles, liquid rocket booster (LRB) derived launch vehicle, and cargo transfer and return vehicle (CTRV).

  8. Blade Testing Trends (Presentation)

    SciTech Connect

    Desmond, M.

    2014-08-01

    As an invited guest speaker, Michael Desmond presented on NREL's NWTC structural testing methods and capabilities at the 2014 Sandia Blade Workshop held on August 26-28, 2014 in Albuquerque, NM. Although dynamometer and field testing capabilities were mentioned, the presentation focused primarily on wind turbine blade testing, including descriptions and capabilities for accredited certification testing, historical methodology and technology deployment, and current research and development activities.

  9. Projection Moire Interferometry for Rotorcraft Applications: Deformation Measurements of Active Twist Rotor Blades

    NASA Technical Reports Server (NTRS)

    Fleming, Gary A.; Soto, Hector L.; South, Bruce W.

    2002-01-01

    Projection Moire Interferometry (PMI) has been used during wind tunnel tests to obtain azimuthally dependent blade bending and twist measurements for a 4-bladed Active Twist Rotor (ATR) system in simulated forward flight. The ATR concept offers a means to reduce rotor vibratory loads and noise by using piezoelectric active fiber composite actuators embedded in the blade structure to twist each blade as they rotate throughout the rotor azimuth. The twist imparted on the blades for blade control causes significant changes in blade loading, resulting in complex blade deformation consisting of coupled bending and twist. Measurement of this blade deformation is critical in understanding the overall behavior of the ATR system and the physical mechanisms causing the reduction in rotor loads and noise. PMI is a non-contacting, video-based optical measurement technique capable of obtaining spatially continuous structural deformation measurements over the entire object surface within the PMI system field-of-view. When applied to rotorcraft testing, PMI can be used to measure the azimuth-dependent blade bending and twist along the full span of the rotor blade. This paper presents the PMI technique as applied to rotorcraft testing, and provides results obtained during the ATR tests demonstrating the PMI system performance. PMI measurements acquired at select blade actuation conditions generating minimum and maximum rotor loads are provided to explore the interrelationship between rotor loads, blade bending, and twist.

  10. SSME HPFTP/AT Turbine Blade Platform Featherseal Damper Design

    NASA Technical Reports Server (NTRS)

    Montgomery, S. K.

    1999-01-01

    (i.e, modes 1 & 2) resonant response. The reduction in turbine blade dynamic response is shown for a typical turbine blade. This paper discusses the design and verification of these dampers. The numerous benefits associated with this design concept warrants consideration in existing and future turbomachinery applications.

  11. Advanced Information Processing System (AIPS) proof-of-concept system functional design I/O network system services

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The function design of the Input/Output (I/O) services for the Advanced Information Processing System (AIPS) proof of concept system is described. The data flow diagrams, which show the functional processes in I/O services and the data that flows among them, are contained. A complete list of the data identified on the data flow diagrams and in the process descriptions are provided.

  12. Preliminary Aerodynamic Investigation of Fan Rotor Blade Morphing

    NASA Technical Reports Server (NTRS)

    Tweedt, Daniel L.

    2012-01-01

    Various new technologies currently under development may enable controlled blade shape variability, or so-called blade morphing, to be practically employed in aircraft engine fans and compressors in the foreseeable future. The current study is a relatively brief, preliminary computational fluid dynamics investigation aimed at partially demonstrating and quantifying the aerodynamic potential of fan rotor blade morphing. The investigation is intended to provide information useful for near-term planning, as well as aerodynamic solution data sets that can be subsequently analyzed using advanced acoustic diagnostic tools, for the purpose of making fan noise comparisons. Two existing fan system models serve as baselines for the investigation: the Advanced Ducted Propulsor fan with a design tip speed of 806 ft/sec and a pressure ratio of 1.294, and the Source Diagnostic Test fan with a design tip speed of 1215 ft/sec and a pressure ratio of 1.470. Both are 22-in. sub-scale, low-noise research fan/nacelle models that have undergone extensive experimental testing in the 9- by 15-foot Low Speed Wind Tunnel at the NASA Glenn Research Center. The study, restricted to fan rotor blade morphing only, involves a fairly simple blade morphing technique. Specifically, spanwise-linear variations in rotor blade-section setting angle are applied to alter the blade shape; that is, the blade is linearly retwisted from hub to tip. Aerodynamic performance comparisons are made between morphed-blade and corresponding baseline configurations on the basis of equal fan system thrust, where rotor rotational speed for the morphed-blade fan is varied to change the thrust level for that configuration. The results of the investigation confirm that rotor blade morphing could be a useful technology, with the potential to enable significant improvements in fan aerodynamic performance. Even though the study is very limited in scope and confined to simple geometric perturbations of two existing fan

  13. Improved best estimate plus uncertainty methodology including advanced validation concepts to license evolving nuclear reactors

    SciTech Connect

    Unal, Cetin; Williams, Brian; Mc Clure, Patrick; Nelson, Ralph A

    2010-01-01

    Many evolving nuclear energy programs plan to use advanced predictive multi-scale multi-physics simulation and modeling capabilities to reduce cost and time from design through licensing. Historically, the role of experiments was primary tool for design and understanding of nuclear system behavior while modeling and simulation played the subordinate role of supporting experiments. In the new era of multi-scale multi-physics computational based technology development, the experiments will still be needed but they will be performed at different scales to calibrate and validate models leading predictive simulations. Cost saving goals of programs will require us to minimize the required number of validation experiments. Utilization of more multi-scale multi-physics models introduces complexities in the validation of predictive tools. Traditional methodologies will have to be modified to address these arising issues. This paper lays out the basic aspects of a methodology that can be potentially used to address these new challenges in design and licensing of evolving nuclear technology programs. The main components of the proposed methodology are verification, validation, calibration, and uncertainty quantification. An enhanced calibration concept is introduced and is accomplished through data assimilation. The goal is to enable best-estimate prediction of system behaviors in both normal and safety related environments. To achieve this goal requires the additional steps of estimating the domain of validation and quantification of uncertainties that allow for extension of results to areas of the validation domain that are not directly tested with experiments, which might include extension of the modeling and simulation (M&S) capabilities for application to full-scale systems. The new methodology suggests a formalism to quantify an adequate level of validation (predictive maturity) with respect to required selective data so that required testing can be minimized for cost

  14. Stainless-Steel-Foam Structures Evaluated for Fan and Rotor Blades

    NASA Technical Reports Server (NTRS)

    Lerch, Bradley A.; Raj, Sai V.; Ghosn, Louis J.; Hebsur, Mohan G.; Cosgriff, Laura M.; Min, James B.; Holland, Frederic A., Jr.

    2005-01-01

    The goal of this project is to use a sandwich structure design, consisting of two stainlesssteel face sheets and a stainless-steel-foam core, to fabricate engine fan and propeller blades. Current fan blades are constructed either of polymer matrix composites (PMCs) or hollow titanium alloys. The PMC blades are expensive and have poor impact resistance on their leading edges, thereby requiring a metallic leading edge to satisfy the Federal Aviation Administration s impact requirements relating to bird strikes. Hollow titanium blades cost more to fabricate because of the intrinsically difficult fabrication issues associated with titanium alloys. However, both these current concepts produce acceptable lightweight fan blades.

  15. The use of optimization techniques to design controlled diffusion compressor blading

    NASA Technical Reports Server (NTRS)

    Sanger, N. L.

    1982-01-01

    A method for automating compressor blade design using numerical optimization, and applied to the design of a controlled diffusion stator blade row is presented. A general purpose optimization procedure is employed, based on conjugate directions for locally unconstrained problems and on feasible directions for locally constrained problems. Coupled to the optimizer is an analysis package consisting of three analysis programs which calculate blade geometry, inviscid flow, and blade surface boundary layers. The optimizing concepts and selection of design objective and constraints are described. The procedure for automating the design of a two dimensional blade section is discussed, and design results are presented.

  16. Active Blade Vibration Control Being Developed and Tested

    NASA Technical Reports Server (NTRS)

    Johnson, Dexter

    2003-01-01

    Gas turbine engines are currently being designed to have increased performance, lower weight and manufacturing costs, and higher reliability. Consequently, turbomachinery components, such as turbine and compressor blades, have designs that are susceptible to new vibration problems and eventual in-service failure due to high-cycle fatigue. To address this problem, researchers at the NASA Glenn Research Center are developing and testing innovative active blade vibration control concepts. Preliminary results of using an active blade vibration control system, involving a rotor supported by an active magnetic bearing in Glenn's Dynamic Spin Rig, indicate promising results (see the photograph). Active blade vibration control was achieved using feedback of blade strain gauge signals within the magnetic bearing control loop. The vibration amplitude was reduced substantially (see the graphs). Also, vibration amplitude amplification was demonstrated; this could be used to enhance structural mode identification, if desired. These results were for a nonrotating two-bladed disk. Tests for rotating blades are planned. Current and future active blade vibration control research is planned to use a fully magnetically suspended rotor and smart materials. For the fully magnetically suspended rotor work, three magnetic bearings (two radial and one axial) will be used as actuators instead of one magnetic bearing. This will allow additional degrees of freedom to be used for control. For the smart materials work, control effectors located on and off the blade will be considered. Piezoelectric materials will be considered for on-the-blade actuation, and actuator placement on a stator vane, or other nearby structure, will be investigated for off-the-blade actuation. Initial work will focus on determining the feasibility of these methods by performing basic analysis and simple experiments involving feedback control.

  17. The Use of Visual Advance Organizers for Learning Earth Science Concepts.

    ERIC Educational Resources Information Center

    Weisberg, Joseph S.

    This study was designed to determine whether advance organizers in the form of visual aids might serve the same function as Ausubel's verbal advance organizers. The basic design of the study consisted of a 4 X 3 X 2 ANOVA factorial design. Ninety-six eighth-grade students were involved in the study. One group was exposed to a physiographic diagram…

  18. Advanced Wind Turbine Drivetrain Concepts: Workshop Report, June 29-30, 2010

    SciTech Connect

    DOE, EERE

    2010-12-01

    This report presents key findings from the Department of Energy's Advanced Drivetrain Workshop, held on June 29-30, 2010 in Broomfield, Colorado, to assess different advanced drivetrain technologies, their relative potential to improve the state-of-the-art in wind turbine drivetrains, and the scope of research and development needed for their commercialization in wind turbine applications.

  19. Innovative design approaches for large wind turbine blades

    NASA Astrophysics Data System (ADS)

    Jackson, K. J.; Zuteck, M. D.; van Dam, C. P.; Standish, K. J.; Berry, D.

    2005-04-01

    A preliminary design study of an advanced 50 m blade for utility wind turbines is presented and discussed. The effort was part of the Department of Energy WindPACT Blade System Design Study with the goal to investigate and evaluate design and manufacturing issues for wind turbine blades in the 1-10 MW size range. Two different blade designs are considered and compared in this article. The first is a fibreglass design, while the second design selectively incorporates carbon fibre in the main structural elements. The addition of carbon results in modest cost increases and provides significant benefits, particularly with respect to blade deflection. The structural efficiency of both designs was maximized by tailoring the thickness of the blade cross-sections to simplify the construction of the internal members. Inboard the blades incorporate thick blunt trailing edge aerofoils (flatback aerofoils), while outboard more conventional sharp trailing edge high-lift aerofoils are used. The outboard section chord lengths were adjusted to yield the least complex and costly internal blade structure. A significant portion of blade weight is related to the root buildup and metal hardware for typical root attachment designs. The results show that increasing the number of studs has a positive effect on total weight, because it reduces the required root laminate thickness. The aerodynamic performance of the blade aerofoils was predicted using computational techniques that properly simulate blunt trailing edge flows. The performance of the rotor was predicted assuming both clean and soiled blade surface conditions. The rotor is shown to provide excellent performance at a weight significantly lower than that of current rotors of this size. Copyright

  20. Impact resistance of composite fan blades. [fiber reinforced graphite and boron epoxy blades for STOL operating conditions

    NASA Technical Reports Server (NTRS)

    Premont, E. J.; Stubenrauch, K. R.

    1973-01-01

    The resistance of current-design Pratt and Whitney Aircraft low aspect ratio advanced fiber reinforced epoxy matrix composite fan blades to foreign object damage (FOD) at STOL operating conditions was investigated. Five graphite/epoxy and five boron/epoxy wide chord fan blades with nickel plated stainless steel leading edge sheath protection were fabricated and impact tested. The fan blades were individually tested in a vacuum whirlpit under FOD environments. The FOD environments were typical of those encountered in service operations. The impact objects were ice balls, gravel, stralings and gelatin simulated birds. Results of the damage sustained from each FOD impact are presented for both the graphite boron reinforced blades. Tests showed that the present design composite fan blades, with wrap around leading edge protection have inadequate FOD impact resistance at 244 m/sec (800 ft/sec) tip speed, a possible STOL operating condition.

  1. SSME blade damper technology

    NASA Technical Reports Server (NTRS)

    Kielb, Robert E.; Griffin, Jerry H.

    1987-01-01

    Before 1975 turbine blade damper designs were based on experience and very simple mathematical models. Failure of the dampers to perform as expected showed the need to gain a better understanding of the physical mechanism of friction dampers. Over the last 10 years research on friction dampers for aeronautical propulsion systems has resulted in methods to optimize damper designs. The first-stage turbine blades on the Space Shuttle Main Engine (SSME) high-pressure oxygen pump have experienced cracking problems due to excessive vibration. A solution is to incorporate a well-designed friction dampers to attenuate blade vibration. The subject study, a cooperative effort between NASA Lewis and Carnegie-Mellon University, represents an application of recently developed friction damper technology to the SSME high-pressure oxygen turbopump. The major emphasis was the contractor's design known as the two-piece damper. Damping occurs at the frictional interface between the top half of the damper and the underside of the platforms of the adjacent blades. The lower half of the damper is an air seal to retard airflow in the volume between blade necks.

  2. Ceramic blade attachment system

    DOEpatents

    Frey, G.A.; Jimenez, O.D.

    1996-12-03

    A turbine blade having a preestablished rate of thermal expansion is attached to a turbine flange having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade. The turbine flange includes a first upstanding flange and a second upstanding flange having a groove formed between them. The turbine flange further includes a recess. Each of the first and second upstanding flanges have a plurality of bores therein. A turbine blade has a first member and a second member positioned in one of the groove and the recess. Each of the first member and the second member have a plurality of bores therein. A pin is positioned in respective ones of the plurality of bores in the first and second upstanding members and the first and second members and attach the blade to the turbine flange. The pin has a preestablished rate of thermal expansion being substantially equal to the rate of thermal expansion of the blade. 4 figs.

  3. Ceramic blade attachment system

    DOEpatents

    Frey, deceased, Gary A.; Jimenez, Oscar D.

    1996-01-01

    A turbine blade having a preestablished rate of thermal expansion is attached to a turbine flange having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade. The turbine flange includes a first upstanding flange and a second upstanding flange having a groove formed therebetween. The turbine flange further includes a recess. Each of the first and second upstanding flanges have a plurality of bores therein. A turbine blade has a first member and a second member positioned in one of the groove and the recess. Each of the first member and the second member have a plurality of bores therein. And, a pin is positioned in respective ones of the plurality of bores in the first and second upstanding members and the first and second members and attach the blade to the turbine flange. The pin has a preestablished rate of thermal expansion being substantially equal to the rate of thermal expansion of the blade.

  4. Improvements to tilt rotor performance through passive blade twist control

    NASA Technical Reports Server (NTRS)

    Nixon, Mark W.

    1988-01-01

    A passive blade twist control is presented in which the twist distribution of a tilt rotor blade is elastically changed as a function of rotor speed. The elastic twist deformation is used to achieve two different blade twist distributions corresponding to the two rotor speeds used on conventional tilt rotors in hover and forward flight. By changing the blade twist distribution, the aerodynamic performance can be improved in both modes of flight. The concept presented obtains a change in twist distribution with extension-twist-coupled composite blade structure. This investigation first determines the linear twists which are optimum for each flight mode. Based on the optimum linear twist distributions, three extension-twist-coupled blade designs are developed using coupled-beam and laminate analyses integrated with an optimization analysis. The designs are optimized for maximum twist deformation subject to material strength limitations. The aerodynamic performances of the final designs are determined which show that the passive blade twist control concept is viable, and can enhance conventional tilt rotor performance.

  5. Duct wall impedance control as an advanced concept for acoustic suppression enhancement. [engine noise reduction

    NASA Technical Reports Server (NTRS)

    Dean, P. D.

    1978-01-01

    A systems concept procedure is described for the optimization of acoustic duct liner design for both uniform and multisegment types. The concept was implemented by the use of a double reverberant chamber flow duct facility coupled with sophisticated computer control and acoustic analysis systems. The optimization procedure for liner insertion loss was based on the concept of variable liner impedance produced by bias air flow through a multilayer, resonant cavity liner. A multiple microphone technique for in situ wall impedance measurements was used and successfully adapted to produce automated measurements for all liner configurations tested. The complete validation of the systems concept was prevented by the inability to optimize the insertion loss using bias flow induced wall impedance changes. This inability appeared to be a direct function of the presence of a higher order energy carrying modes which were not influenced significantly by the wall impedance changes.

  6. Duct wall impedance control as an advanced concept for acoustic impression

    NASA Technical Reports Server (NTRS)

    Dean, P. D.; Tester, B. J.

    1975-01-01

    Models and tests on an acoustic duct liner system which has the property of controlled-variable acoustic impedance are described. This is achieved by a novel concept which uses the effect of steady air flow through a multi-layer, locally reacting, resonant-cavity absorber. The scope of this work was limited to a 'proof of concept.' The test of the concept was implemented by means of a small-scale, square-section flow duct facility designed specifically for acoustic measurements, with one side of the duct acoustically lined. The test liners were designed with the aid of previously established duct acoustic theory and a semi-empirical impedance model of the liner system. Over the limited range tested, the liner behaved primarily as predicted, exhibiting significant changes in resistance and reactance, thus providing the necessary concept validation.

  7. Advanced sulfur control concepts in hot-gas desulfurization technology. Quarterly report, April--June 1994

    SciTech Connect

    Harrison, D.P.

    1994-07-01

    The primary objective of this research project is the direct production of elemental sulfur during the regeneration of known high temperature desulfurization sorbents. The contract was awarded to LSU on April 12, 1994, and this quarterly report covers accomplishments during the first 2 1/2 months of the project. Effort during the initial 2 1/2 month period has been limited to Tasks 1 and 2, and involves a search of the literature to identify concepts for producing elemental sulfur during regeneration of known metal oxide sorbents and a thermodynamic evaluation of these concepts. While searching and evaluating the literature is a continuing process, concentrated effort on that phase is now complete and a detailed summary is included in this report. Three possible concepts for the direct production of elemental sulfur were identified in the LSU proposal, and the literature search has not uncovered any additional concepts. Thus, the three concepts being investigated involve: (1) regeneration with SO{sub 2}, (2) regeneration with mixtures Of 02 and H{sub 2}O, and (3) regeneration with H{sub 2}O. While concept (3) directly produces H{sub 2}S instead of elemental sulfur, the concept is included because the possibility exists for converting H{sub 2}S to elemental sulfur using the Claus process. Each of the concepts will ultimately be compared to the Direct Sulfur Recovery Process (DSRP) under development by RTI. DSRP involves initial sorbent regeneration to SO{sub 2}, and the inclusion of additional processing steps to reduce the SO{sub 2} to elemental sulfur.

  8. Digital system for dynamic turbine engine blade displacement measurements

    NASA Technical Reports Server (NTRS)

    Kiraly, L. J.

    1979-01-01

    An instrumentation concept for measuring blade tip displacements which employs optical probes and an array of micro-computers is presented. The system represents a hitherto unknown instrumentation capability for the acquisition and direct digitization of deflection data concurrently from all of the blade tips of an operational engine rotor undergoing flutter or forced vibration. System measurements are made using optical transducers which are fixed to the case. Measurements made in this way are the equivalent of those obtained by placing three surface-normal displacement transducers at three positions on each blade of an operational rotor.

  9. Proximal Blade Twist Feedback Control for Heliogyro Solar Sails

    NASA Astrophysics Data System (ADS)

    Smith, Sarah Mitchell

    mode is on the order of 0.005%, meaning there is almost no inherent damping in the blade. Next, the proximal blade twist feedback control design was successful in overcoming friction in the root actuator and added damping to the blade. The damping ratio for the lowest frequency torsional mode was increased from 0.001% to 0.09%, which is a significant amount for a heliogyro spacecraft. Finally, the camera sensor used for the proximal differential twist measurement proved to be feasible and quantization from these measurements only decreased the damping ratio to 0.075%. This research provides the first indication that a physically realizable blade root controller can deal with friction in an effective way, thus taking a step towards advancing the technology readiness level of the heliogyro spacecraft.

  10. Stalling of Helicopter Blades

    NASA Technical Reports Server (NTRS)

    Gustafson, F B; Myers, G C , Jr

    1946-01-01

    Theoretical studies have predicted that operation of helicopter rotor beyond certain combinations of thrust, forward speed, and rotational speed might be prevented by rapidly increasing stalling of the retreating blade. The same studies also indicate that the efficiency of the rotor will increase until these limits are reached or closely approached, so that it is desirable to design helicopter rotors for operation close to the limits imposed by blade stalling. Inasmuch as the theoretical predictions of blade stalling involve numerous approximations and assumptions, an experimental investigation was needed to determine whether, in actual practice, the stall did occur and spread as predicted and to establish the amount of stalling that could be present without severe vibration or control difficulties being introduced. This report presents the results of such an investigation.

  11. Blade pressure measurements

    NASA Astrophysics Data System (ADS)

    Chivers, J. W. H.

    Three measurement techniques which enable rotating pressures to be measured during the normal operation of a gas turbine or a component test rig are described. The first technique was developed specifically to provide steady and transient blade surface pressure data to aid both fan flutter research and general fan performance development. This technique involves the insertion of miniature high frequency response pressure transducers into the fan blades of a large civil gas turbine. The other two techniques were developed to measure steady rotating pressures inside and on the surface of engine or rig turbine blades and also rotating pressures in cooling feed systems. These two low frequency response systems are known as the "pressure pineapple' (a name which resulted from the shape of the original prototype) and the rotating scanivalve.

  12. Advanced Melting Technologies: Energy Saving Concepts and Opportunities for the Metal Casting Industry

    SciTech Connect

    none,

    2005-11-01

    The study examines current and emerging melting technologies and discusses their technical barriers to scale-up issues and research needed to advance these technologies, improving melting efficiency, lowering metal transfer heat loss, and reducing scrap.

  13. Using Adult Learning Concepts To Assist Patients in Completing Advance Directives.

    ERIC Educational Resources Information Center

    Meyer, Rose Mary

    2000-01-01

    Advance directives that enable individuals to control their health care are underused due to lack of patient knowledge. Nurses can teach patients about them using adult learning principles, transformation theory, and skills for learning how to learn. (SK)

  14. Status and future directions for advanced accelerator research - conventional and non-conventional collider concepts

    SciTech Connect

    Siemann, R.H.

    1997-01-01

    The relationship between advanced accelerator research and future directions for particle physics is discussed. Comments are made about accelerator research trends in hadron colliders, muon colliders, and e{sup +}3{sup {minus}} linear colliders.

  15. Computerized three-dimensional aerodynamic design of a lifting rotor blade

    NASA Technical Reports Server (NTRS)

    Tauber, M. E.; Hicks, R. M.

    1980-01-01

    A three-dimensional, inviscid, full-potential lifting rotor code was used to demonstrate that pressure distributions on both advancing and retreating blades could be significantly improved by perturbing local airfoil sections. The perturbations were described by simple geometric shape functions. To illustrate the procedure, an example calculation was made at a forward flight speed of 85 m/sec (165 knots) and an advance ratio of 0.385. It was found that a minimum of three shape functions was required to improve the pressures without producing undesirable secondary effects in high-speed forward flight on a hypothetical modern rotor blade initially having an NLR-1 supercritical airfoil. Reductions in the shock strength on the advancing blade could be achieved, while simultaneously lessening leading-edge pressure gradients on the retreating blade. The major blade section modifications required were blunting of the upper surface leading edge and some reshaping of the blade's upper surface resulting in moderately thicker airfoils.

  16. An experimental investigation of the helicopter rotor blade element airloads on a model rotor in the blade stall regime

    NASA Technical Reports Server (NTRS)

    Fisher, R. K., Jr.; Tompkins, J. E.; Bobo, C. J.; Child, R. F.

    1971-01-01

    A wind tunnel test program was conducted on an eight foot diameter model rotor system to determine blade element airloads characteristics in the unstalled and stalled flight regimes. The fully articulated model rotor system utilized three blades with a Vertol 23010-1.58 airfoil section, the blades being 1/7.5 scale models of the Ch-47C rotor blades. Instrumentation was incorporated at the blade 75% radial station to measure pressure and skin friction distributions, surface streamline directions and local angle of attack. The test program was conducted in three phases; non-rotating, hover and forward flight at advance ratios of 0.15, 0.35 and 0.60. Test data were analyzed with respect to providing insight to the mechanisms affecting blade stall, particularly retreating blade stall during forward flight conditions. From such data, an assessment was made as to the applicability of current theoretical analyses used for the prediction of blade element airloads in the stall regime.

  17. A demonstration of passive blade twist control using extension-twist coupling

    NASA Technical Reports Server (NTRS)

    Lake, Renee C.; Nixon, Mark W.; Wilbur, Matthew L.; Singleton, Jeffrey D.; Mirick, Paul H.

    1992-01-01

    The results from a study aimed at improving the dynamic and aerodynamic characteristics of composite rotor blades through the use of extension-twist coupling are presented. A set of low twist model-scale helicopter rotor blades was manufactured with a view towards demonstrating the passive blade twist control concept. Hover testing of the blades was conducted to measure the change in blade twist as a function of rotor speed. The blades were spun through the 0-800 rpm range, with a corresponding sweep of collective pitch to determine the effect on the blade elastic twist. Hover data were obtained for both a ballasted and unballasted blade configuration in atmospheric conditions, where maximum twist changes of 2.54 and 5.24 degrees were respectively observed. These results compared well with those from a finite element analysis of the blade, which yielded maximum twists of 3.01 and 5.61 degrees for the unballasted and ballasted blade configurations, respectively. The aerodynamic-induced effects on the blade elastic twist, determined by testing a ballasted blade configuration in a near-vacuum condition, were found to be minimal with a maximum twist difference of 0.17 degrees observed between the two test environments. The effect of collective pitch sweep on the elastic twist was minimal.

  18. Surface controlled blade stabilizer

    DOEpatents

    Russell, Larry R.

    1983-01-01

    Drill string stabilizer apparatus, controllable to expand and retract entirely from the surface by control of drill string pressure, wherein increase of drill string pressure from the surface closes a valve to create a piston means which is moved down by drill string pressure to expand the stabilizer blades, said valve being opened and the piston moving upward upon reduction of drill string pressure to retract the stabilizer blades. Upward and downward movements of the piston and an actuator sleeve therebelow are controlled by a barrel cam acting between the housing and the actuator sleeve.

  19. Preliminary design concepts for an advanced gas distribution system. Task report, August 1989-August 1990

    SciTech Connect

    Lipinsky, E.S.; Hattery, G.R.; Newaz, G.

    1991-01-01

    Studies that were conducted in 1989 (GRI-89/0107.2) showed that the major problems that face the industry are third-party damage, locatability, and pipe supportability. These needs were translated into performance criteria for materials and designs of gas distribution system components. In Phase 2 to date, the performance criteria were refined and used as the basis for generation of concepts for materials and designs for enhancement of the gas distribution system. The screening criteria include long service life, damage tolerance, installation, and manufacturability. A scoring model that allows the criteria to have variable weights was applied to attain normalized scores and rankings for the concepts. The leading concepts include puncture-resistant polyethylene pipe via wrapping with an ultrahigh molecular weight polyethylene fabric or fiber, toughened thermoplastics (especially polyamides or acetal resin or polyester), thermoplastic fiber-reinforced thermoplastic resins, fiberglass-reinforced hose designs, and honeycomb-reinforced thermoplastic elastomer designs. Tentative research and development plans were developed for the leading concepts in which simple tests of manufacturability, impact resistance, and joinability are to be used to determine which concepts should be pursued further and which appear to have serious flaws.

  20. Cooled snubber structure for turbine blades

    DOEpatents

    Mayer, Clinton A; Campbell, Christian X; Whalley, Andrew; Marra, John J

    2014-04-01

    A turbine blade assembly in a turbine engine. The turbine blade assembly includes a turbine blade and a first snubber structure. The turbine blade includes an internal cooling passage containing cooling air. The first snubber structure extends outwardly from a sidewall of the turbine blade and includes a hollow interior portion that receives cooling air from the internal cooling passage of the turbine blade.