Science.gov

Sample records for airbreathing propulsion branch

  1. Guidance and control of an earth to orbit vehicle with optimum transition from airbreathing to concurrent airbreathing/rocket propulsion

    NASA Astrophysics Data System (ADS)

    Kauffman, H. G.; Grandhi, R. V.; Hankey, W. L.; Belcher, P. J.

    1990-07-01

    An efficient performance analysis method (suitable for PC operation) is developed to evaluate potential airbreathing/rocket propulsion systems for advanced technology single-stage-to-orbit (SSTO) launch vehicles. Evaluated are tradeoffs between airbreathing (AB), rocket, and concurrent airbreathing/rocket propulsion in minimizing fuel consumption for a given ascent flight trajectory. Many mission, flight, and vehicle related requirements and constraints are satisfied in the process. With the analysis method, several modes of airbreathing/rocket propulsion are compared to a baseline 'airbreather alone' propulsion system in terms of fuel required to attain orbital velocity. The optimal switch point (staging) is identified for the transition from airbreathing to rocket propulsion.

  2. Experimental investigation of a unique airbreathing pulsed laser propulsion concept

    NASA Technical Reports Server (NTRS)

    Myrabo, L. N.; Nagamatsu, H. T.; Manka, C.; Lyons, P. W.; Jones, R. A.

    1991-01-01

    Investigations were conducted into unique methods of converting pulsed laser energy into propulsive thrust across a flat impulse surface under atmospheric conditions. The propulsion experiments were performed with a 1-micron neodymium-glass laser at the Space Plasma Branch of the Naval Research Laboratory. Laser-induced impulse was measured dynamically by ballistic pendulums and statically using piezoelectric pressure transducers on a stationary impulse surface. The principal goal was to explore methods for increasing the impulse coupling performance of airbreathing laser-propulsion engines. A magnetohydrodynamic thrust augmentation effect was discovered when a tesla-level magnetic field was applied perpendicular to the impulse surface. The impulse coupling coefficient performance doubled and continued to improve with increasing laser-pulse energies. The resultant performance of 180 to 200 N-s/MJ was found to be comparable to that of the earliest afterburning turbojets.

  3. Improved airbreathing launch vehicle performance with the use of rocket propulsion

    NASA Astrophysics Data System (ADS)

    Kauffman, H. G.; Grandhi, R. V.; Hankey, W. L.; Belcher, P. J.

    1991-04-01

    An efficient performance analysis method is developed to evaluate potential airbreathing/rocket propulsion systems for advanced technology single-stage-to-orbit launch vehicles. Evaluated are tradeoffs between airbreathing, rocket, and concurrent airbreathing/rocket propulsion in maximizing payload delivery to orbit for a given ascent flight trajectory. With the analysis method, several modes of airbreathing/rocket propulsion are compared to a baseline 'airbreather alone' propulsion system in terms of fuel/propellant required to attain orbital velocity. Concurrent airbreathing/rocket propulsion shows a reduction in fuel/propellant consumption over straight airbreather to rocket propulsion transition. The optimal switch point (staging) is identified for the transition from airbreathing to rocket propulsion.

  4. Optimization of Air-Breathing Propulsion Engine Concepts

    NASA Technical Reports Server (NTRS)

    Patnaik, Surya N.; Hopkins, Dale A.

    1997-01-01

    Air-breathing propulsion engines play an important role in the development of both civil and military aircraft Design optimization of such engines can lead to higher power, or more thrust for less fuel consumption. A multimission propulsion engine design can be modeled mathematically as a multivariable global optimization problem, with a sequence of subproblems, which are specific to the mission events defined through Mach number, altitude, and power setting combinations.

  5. Laser-driven hypersonic air-breathing propulsion simulator

    NASA Technical Reports Server (NTRS)

    Joshi, Prakash B.; Lo, Edmond Y.; Pugh, Evan R.

    1992-01-01

    A feasibility study is presented of simulating airbreathing propulsion on small scale hypersonic models using laser energy. The laser heat addition scheme allows simultaneous inlet and exhaust flows during wind tunnel testing of models with scramjet models. The proposed propulsion simulation concept has extended the Kantrowitz (1974) idea to propulsive wind tunnel models of hypersonic aircraft. Critical issues in aeropropulsive testing of models based on a ramjet power plant are addressed which include transfer of the correct amount of energy to the flowing gas, efficient absorption of laser energy into the gas, and test performance under tunnel reservoir conditions and at reasonable Reynolds numbers.

  6. Aeronautical facilities catalogue. Volume 2: Airbreathing propulsion and flight simulators

    NASA Technical Reports Server (NTRS)

    Penaranda, F. E.; Freda, M. S.

    1985-01-01

    Volume two of the facilities catalogue deals with Airbreathing Propulsion and Flight Simulation Facilities. Data pertinent to managers and engineers are presented. Each facility is described on a data sheet that shows the facility's technical parameters on a chart and more detailed information in narratives. Facilities judged comparable in testing capability are noted and grouped together. Several comprehensive cross-indexes and charts are included.

  7. Fluid dynamic problems associated with air-breathing propulsive systems

    NASA Technical Reports Server (NTRS)

    Chow, W. L.

    1979-01-01

    A brief account of research activities on problems related to air-breathing propulsion is made in this final report for the step funded research grant NASA NGL 14-005-140. Problems include the aircraft ejector-nozzle propulsive system, nonconstant pressure jet mixing process, recompression and reattachment of turbulent free shear layer, supersonic turbulent base pressure, low speed separated flows, transonic boattail flow with and without small angle of attack, transonic base pressures, Mach reflection of shocks, and numerical solution of potential equation through hodograph transformation.

  8. 26th JANNAF Airbreathing Propulsion Subcommittee Meeting. Volume 1

    NASA Technical Reports Server (NTRS)

    Fry, Ronald S. (Editor); Gannaway, Mary T. (Editor)

    2002-01-01

    This volume, the first of four volumes, is a collection of 28 unclassified/unlimited-distribution papers which were presented at the Joint Army-Navy-NASA-Air Force (JANNAF) 26th Airbreathing Propulsion Subcommittee (APS) was held jointly with the 38th Combustion Subcommittee (CS), 20th Propulsion Systems Hazards Subcommittee (PSHS), and 2nd Modeling and Simulation Subcommittee. The meeting was held 8-12 April 2002 at the Bayside Inn at The Sandestin Golf & Beach Resort and Eglin Air Force Base, Destin, Florida. Topics covered include: scramjet and ramjet R&D program overviews; tactical propulsion; space access; NASA GTX status; PDE technology; actively cooled engine structures; modeling and simulation of complex hydrocarbon fuels and unsteady processes; and component modeling and simulation.

  9. Innovative Airbreathing Propulsion Concepts for High-speed Applications

    NASA Technical Reports Server (NTRS)

    Whitlow, Woodrow, Jr.

    2002-01-01

    The current cost to launch payloads to low earth orbit (LEO) is approximately loo00 U.S. dollars ($) per pound ($22000 per kilogram). This high cost limits our ability to pursue space science and hinders the development of new markets and a productive space enterprise. This enterprise includes NASA's space launch needs and those of industry, universities, the military, and other U.S. government agencies. NASA's Advanced Space Transportation Program (ASTP) proposes a vision of the future where space travel is as routine as in today's commercial air transportation systems. Dramatically lower launch costs will be required to make this vision a reality. In order to provide more affordable access to space, NASA has established new goals in its Aeronautics and Space Transportation plan. These goals target a reduction in the cost of launching payloads to LEO to $lo00 per pound ($2200 per kilogram) by 2007 and to $100' per pound by 2025 while increasing safety by orders of magnitude. Several programs within NASA are addressing innovative propulsion systems that offer potential for reducing launch costs. Various air-breathing propulsion systems currently are being investigated under these programs. The NASA Aerospace Propulsion and Power Base Research and Technology Program supports long-term fundamental research and is managed at GLenn Research Center. Currently funded areas relevant to space transportation include hybrid hyperspeed propulsion (HHP) and pulse detonation engine (PDE) research. The HHP Program currently is addressing rocket-based combined cycle and turbine-based combined cycle systems. The PDE research program has the goal of demonstrating the feasibility of PDE-based hybrid-cycle and combined cycle propulsion systems that meet NASA's aviation and access-to-space goals. The ASTP also is part of the Base Research and Technology Program and is managed at the Marshall Space Flight Center. As technologies developed under the Aerospace Propulsion and Power Base

  10. An Overview of SBIR Phase 2 Airbreathing Propulsion Technologies

    NASA Technical Reports Server (NTRS)

    Nguyen, Hung D.; Steele, Gynelle C.; Bitler, Dean W.

    2014-01-01

    Technological innovation is the overall focus of NASA's Small Business Innovation Research (SBIR) program. The program invests in the development of innovative concepts and technologies to help NASA's mission directorates address critical research and development needs for agency projects. This report highlights innovative SBIR Phase II projects from 2007-2012 specifically addressing areas in Airbreathing Propulsion which is one of six core competencies at NASA Glenn Research Center. There are twenty technologies featured with emphasis on a wide spectrum of applications such as with a Turbo-Brayton cryocooler for aircraft superconducting systems, braided composite rotorcraft structures, engine air brake, combustion control valve, flexible composite driveshaft, and much more. Each article in this booklet describes an innovation, technical objective, and highlights NASA commercial and industrial applications. This report serves as an opportunity for NASA personnel including engineers, researchers, and program managers to learn of NASA SBIR's capabilities that might be crosscutting into this technology area. As the result, it would cause collaborations and partnerships between the small companies and NASA Programs and Projects resulting in benefit to both SBIR companies and NASA.

  11. Combining MHD Airbreathing and Fusion Rocket Propulsion for Earth-to-Orbit Flight

    SciTech Connect

    Froning, H. D. Jr; Yang, Yang; Momota, H.; Burton, E.; Miley, G. H.; Luo, Nie

    2005-02-06

    Previous studies have shown that Single-State-to-Orbit (SSTO) vehicle propellant can be reduced by Magnets-Hydro-Dynamic (MHD) processes that minimize airbreathing propulsion losses and propellant consumption during atmospheric flight. Similarly additional reduction in SSTO propellant is enabled by Inertial Electrostatic Confinement (IEC) fusion, whose more energetic reactions reduce rocket propellant needs. MHD airbreathing propulsion during an SSTO vehicle's initial atmospheric flight phase and IEC fusion propulsion during its final exo-atmospheric flight phase is therefore being explored. Accomplished work is not yet sufficient for claiming such a vehicle's feasibility. But takeoff and propellant mass for an MHD airbreathing and IEC fusion vehicle could be as much as 25 and 40 percent less than one with ordinary airbreathing and IEC fusion; and as much as 50 and 70 percent less than SSTO takeoff and propellant mass with MHD airbreathing and chemical rocket propulsion. Thus this unusual combined cycle engine shows great promise for performance gains beyond contemporary combined-cycle airbreathing engines.

  12. Research in Hypersonic Airbreathing Propulsion at the NASA Langley Research Center

    NASA Technical Reports Server (NTRS)

    Kumar, Ajay; Drummond, J. Philip; McClinton, Charles R.; Hunt, James L.

    2001-01-01

    The NASA Langley Research Center has been conducting research for over four decades to develop technology for an airbreathing-propelled vehicle. Several other organizations within the United States have also been involved in this endeavor. Even though significant progress has been made over this period, a hypersonic airbreathing vehicle has not yet been realized due to low technology maturity. One of the major reasons for the slow progress in technology development has been the low level and cyclic nature of funding. The paper provides a brief historical overview of research in hypersonic airbreathing technology and then discusses current efforts at NASA Langley to develop various analytical, computational, and experimental design tools and their application in the development of future hypersonic airbreathing vehicles. The main focus of this paper is on the hypersonic airbreathing propulsion technology.

  13. A conceptual design of an unmanned test vehicle using an airbreathing propulsion system

    NASA Technical Reports Server (NTRS)

    1992-01-01

    According to Aviation Week and Space Technology (Nov. 16, 1992), without a redefined approach to the problem of achieving single stage-to-orbit flight, the X-30 program is virtually assured of cancellation. One of the significant design goals of the X-30 program is to achieve single stage to low-earth orbit using airbreathing propulsion systems. In an attempt to avoid cancellation, the NASP Program has decided to design a test vehicle to achieve these goals. This report recommends a conceptual design of an unmanned test vehicle using an airbreathing propulsion system.

  14. Minimum-fuel ascent to orbit using air-breathing propulsion

    NASA Technical Reports Server (NTRS)

    Van Buren, Mark A.; Mease, Kenneth D.

    1989-01-01

    Single-stage vehicles using air-breathing propulsion hold promise for more economical delivery of payloads to orbit. The characterization of minimum-fuel trajectories over the range of possible engine and aerodynamic performance of such vehicles provides useful feedback to engine and vehicle designers and paves the way for the development of guidance logic. The minimum-fuel trajectory problem is formulated, propulsion system and aerodynamic models are presented, a numerical solution approach is described, and some preliminary results are discussed.

  15. Propulsion Airframe Integration Test Techniques for Hypersonic Airbreathing Configurations at NASA Langley Research Center

    NASA Technical Reports Server (NTRS)

    Witte, David W.; Huebner, Lawrence D.; Trexler, Carl A.; Cabell, Karen F.; Andrews, Earl H., Jr.

    2003-01-01

    The scope and significance of propulsion airframe integration (PAI) for hypersonic airbreathing vehicles is presented through a discussion of the PAI test techniques utilized at NASA Langley Research Center. Four primary types of PAI model tests utilized at NASA Langley for hypersonic airbreathing vehicles are discussed. The four types of PAI test models examined are the forebody/inlet test model, the partial-width/truncated propulsion flowpath test model, the powered exhaust simulation test model, and the full-length/width propulsion flowpath test model. The test technique for each of these four types of PAI test models is described, and the relevant PAI issues addressed by each test technique are illustrated through the presentation of recent PAI test data.

  16. Impact of aeroelasticity on propulsion and longitudinal flight dynamics of an air-breathing hypersonic vehicle

    NASA Technical Reports Server (NTRS)

    Raney, David L.; Mcminn, John D.; Pototzky, Anthony S.; Wooley, Christine L.

    1993-01-01

    Many air-breathing hypersonic aerospacecraft design concepts incorporate an elongated fuselage forebody acting as the aerodynamic compression surface for a hypersonic combustion module, or scram jet. This highly integrated design approach creates the potential for an unprecedented form of aero-propulsive-elastic interaction in which deflections of the vehicle fuselage give rise to propulsion transients, producing force and moment variations that may adversely impact the rigid body flight dynamics and/or further excite the fuselage bending modes. To investigate the potential for such interactions, a math model was developed which included the longitudinal flight dynamics, propulsion system, and first seven elastic modes of a hypersonic air-breathing vehicle. Perturbation time histories from a simulation incorporating this math model are presented that quantify the propulsive force and moment variations resulting from aeroelastic vehicle deflections. Root locus plots are presented to illustrate the effect of feeding the propulsive perturbations back into the aeroelastic model. A concluding section summarizes the implications of the observed effects for highly integrated hypersonic air-breathing vehicle concepts.

  17. JANNAF Airbreathing Propulsion Subcommittee and 35th Combustion Subcommittee Meeting. Volume 1

    NASA Technical Reports Server (NTRS)

    Fry, Ronald S. (Editor); Gannaway, Mary T. (Editor); Rognan, Melanie (Editor)

    1998-01-01

    This document, CPIA Publication 682, Volume 1, is a compilation of 5 unclassified/unlimited technical papers (approved for public release) which were presented at the 1 998 meeting of the Joint Army-Navy-NASA-Air Force (JANNAF) Airbreathing Propulsion Subcommittee (APS) and Combustion Subcommittee (CS) held jointly with the Propulsion Systems Hazards Subcommittee (PSHS). The meeting was held on 7-11 December 1998 at Raytheon Systems Company and the Marriott Hotel, Tucson, AZ. Topics covered include HyTech technology development, hydrocarbon fuel development for hypersonic applications, pulse detonation propulsion system development and arc heaters for direct-connect scramjet testing.

  18. Survey of Aerothermodynamics Facilities Useful for the Design of Hypersonic Vehicles Using Air-Breathing Propulsion

    NASA Technical Reports Server (NTRS)

    Arnold, James O.; Deiwert, George S.

    1997-01-01

    This paper surveys the use of aerothermodynamic facilities which have been useful in the study of external flows and propulsion aspects of hypersonic, air-breathing vehicles. While the paper is not a survey of all facilities, it covers the utility of shock tunnels and conventional hypersonic blow-down facilities which have been used for hypersonic air-breather studies. The problems confronting researchers in the field of aerothermodynamics are outlined. Results from the T5 GALCIT tunnel for the shock-on lip problem are outlined. Experiments on combustors and short expansion nozzles using the semi-free jet method have been conducted in large shock tunnels. An example which employed the NASA Ames 16-Inch shock tunnel is outlined, and the philosophy of the test technique is described. Conventional blow-down hypersonic wind tunnels are quite useful in hypersonic air-breathing studies. Results from an expansion ramp experiment, simulating the nozzle on a hypersonic air-breather from the NASA Ames 3.5 Foot Hypersonic wind tunnel are summarized. Similar work on expansion nozzles conducted in the NASA Langley hypersonic wind tunnel complex is cited. Free-jet air-frame propulsion integration and configuration stability experiments conducted at Langley in the hypersonic wind tunnel complex on a small generic model are also summarized.

  19. Calibration of the Langley 8-Foot High Temperature Tunnel for Hypersonic Airbreathing Propulsion Testing

    NASA Technical Reports Server (NTRS)

    Huebner, Lawrence D.; Rock, Kenneth E.; Voland, Randall T.; Wieting, Allan R.

    1996-01-01

    The NASA Langley 8-Foot High Temperature Tunnel has recently been modified to produce a unique testing capability for hypersonic airbreathing propulsion systems. Prior to these modifications, the facility was used primarily for aerothermal loads and structural verification testing at true flight total enthalpy conditions for Mach numbers between 6 and 7. One of the recent modifications was an oxygen replenishment system which allows operating airbreathing propulsion systems to be tested at true flight total enthalpies. Following the modifications to the facility, calibration runs were performed at total enthalpies corresponding to flight Mach numbers of 6.3 and 6.8 to establish the flow characteristics of the facility with its new capabilities. The results of this calibration, as well as modifications to tunnel combustor hardware prior to calibration to improve tunnel flow quality, are described in this paper.

  20. Advances in computational design and analysis of airbreathing propulsion systems

    NASA Technical Reports Server (NTRS)

    Klineberg, John M.

    1989-01-01

    The development of commercial and military aircraft depends, to a large extent, on engine manufacturers being able to achieve significant increases in propulsion capability through improved component aerodynamics, materials, and structures. The recent history of propulsion has been marked by efforts to develop computational techniques that can speed up the propulsion design process and produce superior designs. The availability of powerful supercomputers, such as the NASA Numerical Aerodynamic Simulator, and the potential for even higher performance offered by parallel computer architectures, have opened the door to the use of multi-dimensional simulations to study complex physical phenomena in propulsion systems that have previously defied analysis or experimental observation. An overview of several NASA Lewis research efforts is provided that are contributing toward the long-range goal of a numerical test-cell for the integrated, multidisciplinary design, analysis, and optimization of propulsion systems. Specific examples in Internal Computational Fluid Mechanics, Computational Structural Mechanics, Computational Materials Science, and High Performance Computing are cited and described in terms of current capabilities, technical challenges, and future research directions.

  1. Airbreathing Propulsion System Analysis Using Multithreaded Parallel Processing

    NASA Technical Reports Server (NTRS)

    Schunk, Richard Gregory; Chung, T. J.; Rodriguez, Pete (Technical Monitor)

    2000-01-01

    In this paper, parallel processing is used to analyze the mixing, and combustion behavior of hypersonic flow. Preliminary work for a sonic transverse hydrogen jet injected from a slot into a Mach 4 airstream in a two-dimensional duct combustor has been completed [Moon and Chung, 1996]. Our aim is to extend this work to three-dimensional domain using multithreaded domain decomposition parallel processing based on the flowfield-dependent variation theory. Numerical simulations of chemically reacting flows are difficult because of the strong interactions between the turbulent hydrodynamic and chemical processes. The algorithm must provide an accurate representation of the flowfield, since unphysical flowfield calculations will lead to the faulty loss or creation of species mass fraction, or even premature ignition, which in turn alters the flowfield information. Another difficulty arises from the disparity in time scales between the flowfield and chemical reactions, which may require the use of finite rate chemistry. The situations are more complex when there is a disparity in length scales involved in turbulence. In order to cope with these complicated physical phenomena, it is our plan to utilize the flowfield-dependent variation theory mentioned above, facilitated by large eddy simulation. Undoubtedly, the proposed computation requires the most sophisticated computational strategies. The multithreaded domain decomposition parallel processing will be necessary in order to reduce both computational time and storage. Without special treatments involved in computer engineering, our attempt to analyze the airbreathing combustion appears to be difficult, if not impossible.

  2. JANNAF 24th Airbreathing Propulsion Subcommittee and 36th Combustion Subcommittee Joint Meeting. Volume 1

    NASA Technical Reports Server (NTRS)

    Fry, Ronald S. (Editor); Gannaway, Mary T. (Editor)

    1999-01-01

    Volume 1, the first of three volumes is a compilation of 16 unclassified/unlimited-technical papers presented at the Joint Army-Navy-NASA-Air Force (JANNAF) 24th Airbreathing Propulsion Subcommittee and 36th Combustion Subcommittee held jointly with the 181 Propulsion Systems Hazards Subcommittee. The meeting was held on 18-21 October 1999 at NASA Kennedy Space Center and The DoubleTree Oceanfront Hotel, Cocoa Beach, Florida. Topics covered include overviews of RBCC and PDE hypersonic technology, Hyper-X propulsion ground testing, development of JP-8 for hypersonic vehicle applications, numerical simulation of dual-mode SJ combustion, V&V of M&S computer codes, MHD SJ and Rocket Based Combined Cycle (RBCC) launch vehicle concepts, and Pulse Detonation Engine (PDE) propulsion technology development including fundamental investigations, modeling, aerodynamics, operation and performance.

  3. Innovative Airbreathing Propulsion Concepts for Access to Space

    NASA Technical Reports Server (NTRS)

    Whitlow, Jr., Woodrow; Blech, Richard A.; Blankson, Isaiah M.

    2001-01-01

    This paper will present technologies and concepts for novel aeropropulsion systems. These technologies will enhance the safety of operations, reduce life cycle costs, and contribute to reduced costs of air travel and access to space. One of the goals of the NASA program is to reduce the carbon-dioxide emissions of aircraft engines. Engine concepts that use highly efficient fuel cell/electric drive technologies in hydrogen-fueled engines will be presented in the proposed paper. Carbon-dioxide emissions will be eliminated by replacing hydrocarbon fuel with hydrogen, and reduce NOx emissions through better combustion process control. A revolutionary exoskeletal engine concept, in which the engine drum is rotated, will be shown. This concept has the potential to allow a propulsion system that can be used for subsonic through hypersonic flight. Dual fan concepts that have ultra-high bypass ratios, low noise, and low drag will be presented. Flow-controlled turbofans and control-configured turbofans also will be discussed. To increase efficiency, a system of microengines distributed along lifting surfaces and on the fuselage is being investigated. This concept will be presented in the paper. Small propulsion systems for affordable, safe personal transportation vehicles will be discussed. These low-oil/oilless systems use technologies that enable significant cost and weight reductions. Pulse detonation engine-based hybrid-cycle and combined-cycle propulsion systems for aviation and space access will be presented.

  4. Air-breathing aerospace plane development essential: Hypersonic propulsion flight tests

    NASA Technical Reports Server (NTRS)

    Mehta, Unmeel B.

    1994-01-01

    Hypersonic air-breathing propulsion utilizing scramjets can fundamentally change transatmospheric accelerators for low earth-to-orbit and return transportation. The value and limitations of ground tests, of flight tests, and of computations are presented, and scramjet development requirements are discussed. It is proposed that near full-scale hypersonic propulsion flight tests are essential for developing a prototype hypersonic propulsion system and for developing computational-design technology so that it can be used for designing this system. In order to determine how these objectives should be achieved, some lessons learned from past programs are presented. A conceptual two-stage-to-orbit (TSTO) prototype/experimental aerospace plane is recommended as a means of providing access-to-space and for conducting flight tests. A road map for achieving these objectives is also presented.

  5. Hypersonic propulsion flight tests as essential to air-breathing aerospace plane development

    NASA Technical Reports Server (NTRS)

    Mehta, U.

    1995-01-01

    Hypersonic air-breathing propulsion utilizing scramjets can fundamentally change transatmospheric acclerators for transportation from low Earth orbits (LEOs). The value and limitations of ground tests, of flight tests, and of computations are presented, and scramjet development requirements are discussed. Near-full-scale hypersonic propulsion flight tests are essential for developing a prototype hypersonic propulsion system and for developing computation-design technology that can be used in designing that system. In order to determine how these objectives should be achieved, some lessons learned from past programs are presented. A conceptual two-stage-to-orbit (TSTO) prototype/experimental aerospace plane is recommended as a means of providing access-to-space and for conducting flight tests. A road map for achieving these objectives is also presented.

  6. The QED engine spectrum - Fusion-electric propulsion for air-breathing to interstellar flight

    NASA Technical Reports Server (NTRS)

    Bussard, Robert W.; Jameson, Lorin W.

    1993-01-01

    A new inertial-electrostatic-fusion direct electric power source can be used to drive a relativistic e-beam to heat propellant. The resulting system is shown to yield specific impulse and thrust/mass ratio 2-3 orders of magnitude larger than from other advanced propulsion concepts. This QED system can be applied to aerospace vehicles from air-breathing to near-interstellar flight. Examples are given for Earth/Mars flight missions, that show transit times of 40 d with 20 percent payload in single-stage vehicles.

  7. Turbojet-type engines for the airbreathing propulsion of reusable winged launchers

    NASA Astrophysics Data System (ADS)

    Duparcq, J. L.; Hermant, E.; Scherrer, D.

    Combined propulsion systems for hypersonic application have become new challenges for industrial and research organizations. In France, SNECMA and SEP, which have just joined together for a common effort on hypersonics within Hyperspace, and ONERA have been involved, under CNES (French space agency) contracts, in the assessment of new propulsion concepts for reusable winged launchers (SSTO or TSTO). As potential solutions for the airbreathing propulsion, some turbojet-type engines are presented: —the twin spool turbojet or turbofan with reheat —the turbojet with reheat —the twin-duct turbojet ramjet —the precooled turbojet with reheat. All these engines have been sized for a flight Mach number under seven with a cryogenic fuel (liquid hydrogen). Mainly due to total temperature and pressure encountered along the trajectory, the systems will have to withstand severe physical constraints. Coupled with performance and size requirements, like specific thrust and maximum air capture area, these operating conditions have been taken into account in order to select each engine cycle and technical arrangement. Performance and mass criteria make it possible to compare these systems and to emphasize their distinctive features among the propulsion concepts envisioned for the future reusable winged launchers (including airbreathing combined engines under study in France). The first step of the final selection, leading to the best adaptation between the engine and the vehicle, will then be tackled. This will be particularly enhanced by the analysis of potential advantages or technical difficulties, like thrust-to-weight ratio or needs of variable geometry and heat exchangers. The twin-duct turbojet ramjet, for example, is probably one of the best candidates for the first stages of propulsion of a reusable winged launcher.

  8. Air-breathing aerospace plane development essential: Hypersonic propulsion flight tests

    NASA Technical Reports Server (NTRS)

    Mehta, Unmeel B.

    1995-01-01

    Hypersonic airbreathing propulsion utilizing scramjets can change transatmospheric accelerators for low earth-to-orbit and return transportation. The value and limitation of ground tests, of flight tests, and of computations are presented, and scramjet development requirements are discussed. It is proposed that near full-scale hypersonic propulsion flight tests are essential for developing computational design technology so that it can be used for designing this system. In order to determine how these objectives should be achieved, some lessons learned from past programs are presented. A conceptual two-stage-to-orbit (TSTO) prototype/experimental aerospace plane is recommended as a means of providing access-to-space and for conducting flight tests.

  9. Hypersonic Airbreathing Propulsion: An Aerodynamics, Aerothermodynamics, and Acoustics Competency White Paper

    NASA Technical Reports Server (NTRS)

    Drummond, J. Philip; Cockrell, Charles E., Jr.; Pellett, Gerald L.; Diskin, Glenn S.; Auslender, Aaron H.; Exton, Reginald J.; Guy, R. Wayne; Hoppe, John C.; Puster, Richard L.; Rogers, R. Clayton

    2002-01-01

    This White Paper examines the current state of Hypersonic Airbreathing Propulsion at the NASA Langley Research Center and the factors influencing this area of work and its personnel. Using this knowledge, the paper explores beyond the present day and suggests future directions and strategies for the field. Broad views are first taken regarding potential missions and applications of hypersonic propulsion. Then, candidate propulsion systems that may be applicable to these missions are suggested and discussed. Design tools and experimental techniques for developing these propulsion systems are then described, and approaches for applying them in the design process are considered. In each case, current strategies are reviewed and future approaches that may improve the techniques are considered. Finally, the paper concentrates on the needs to be addressed in each of these areas to take advantage of the opportunities that lay ahead for both the NASA Langley Research Center and the Aerodynamic Aerothermodynamic, and Aeroacoustics Competency. Recommendations are then provided so that the goals set forth in the paper may be achieved.

  10. Cascade Optimization Strategy for Aircraft and Air-Breathing Propulsion System Concepts

    NASA Technical Reports Server (NTRS)

    Patnaik, Surya N.; Lavelle, Thomas M.; Hopkins, Dale A.; Coroneos, Rula M.

    1996-01-01

    Design optimization for subsonic and supersonic aircraft and for air-breathing propulsion engine concepts has been accomplished by soft-coupling the Flight Optimization System (FLOPS) and the NASA Engine Performance Program analyzer (NEPP), to the NASA Lewis multidisciplinary optimization tool COMETBOARDS. Aircraft and engine design problems, with their associated constraints and design variables, were cast as nonlinear optimization problems with aircraft weight and engine thrust as the respective merit functions. Because of the diversity of constraint types and the overall distortion of the design space, the most reliable single optimization algorithm available in COMETBOARDS could not produce a satisfactory feasible optimum solution. Some of COMETBOARDS' unique features, which include a cascade strategy, variable and constraint formulations, and scaling devised especially for difficult multidisciplinary applications, successfully optimized the performance of both aircraft and engines. The cascade method has two principal steps: In the first, the solution initiates from a user-specified design and optimizer, in the second, the optimum design obtained in the first step with some random perturbation is used to begin the next specified optimizer. The second step is repeated for a specified sequence of optimizers or until a successful solution of the problem is achieved. A successful solution should satisfy the specified convergence criteria and have several active constraints but no violated constraints. The cascade strategy available in the combined COMETBOARDS, FLOPS, and NEPP design tool converges to the same global optimum solution even when it starts from different design points. This reliable and robust design tool eliminates manual intervention in the design of aircraft and of air-breathing propulsion engines where it eases the cycle analysis procedures. The combined code is also much easier to use, which is an added benefit. This paper describes COMETBOARDS

  11. Evaluation of an Ejector Ramjet Based Propulsion System for Air-Breathing Hypersonic Flight

    NASA Technical Reports Server (NTRS)

    Thomas, Scott R.; Perkins, H. Douglas; Trefny, Charles J.

    1997-01-01

    A Rocket Based Combined Cycle (RBCC) engine system is designed to combine the high thrust to weight ratio of a rocket along with the high specific impulse of a ramjet in a single, integrated propulsion system. This integrated, combined cycle propulsion system is designed to provide higher vehicle performance than that achievable with a separate rocket and ramjet. The RBCC engine system studied in the current program is the Aerojet strutjet engine concept, which is being developed jointly by a government-industry team as part of the Air Force HyTech program pre-PRDA activity. The strutjet is an ejector-ramjet engine in which small rocket chambers are embedded into the trailing edges of the inlet compression struts. The engine operates as an ejector-ramjet from takeoff to slightly above Mach 3. Above Mach 3 the engine operates as a ramjet and transitions to a scramjet at high Mach numbers. For space launch applications the rockets would be re-ignited at a Mach number or altitude beyond which air-breathing propulsion alone becomes impractical. The focus of the present study is to develop and demonstrate a strutjet flowpath using hydrocarbon fuel at up to Mach 7 conditions.

  12. Experimental Study of the Momentum Coupling Coefficient with the Pulse Frequency and Ambient Pressure for Air-Breathing Laser Propulsion

    NASA Astrophysics Data System (ADS)

    Tang, Zhiping; Cai, Jian; Gong, Ping; Hu, Xiaojun; Tan, Rongqin; Zheng, Zhijun; Wu, Jin; Lu, Yan

    2006-05-01

    The air-breathing laser propulsion tests are conducted for parabolic models by using a high power TEA-CO2 pulsed laser. It is found the momentum coupling coefficient Cm varies with the pulse repeatable frequency and reaches the maximum near 50Hz. With a multi-use pendulum chamber, the change of Cm at different ambient pressure is measured. The experimental results show that the propulsion efficiency Cm does not decrease below the altitude of 10km, even increases a little bit. The calculated Cm fits the experimental result up to altitude 3km, then, they are separated. One possible reason is the temperature which is constant in the experiments.

  13. Propulsion integration of hypersonic air-breathing vehicles utilizing a top-down design methodology

    NASA Astrophysics Data System (ADS)

    Kirkpatrick, Brad Kenneth

    In recent years, a focus of aerospace engineering design has been the development of advanced design methodologies and frameworks to account for increasingly complex and integrated vehicles. Techniques such as parametric modeling, global vehicle analyses, and interdisciplinary data sharing have been employed in an attempt to improve the design process. The purpose of this study is to introduce a new approach to integrated vehicle design known as the top-down design methodology. In the top-down design methodology, the main idea is to relate design changes on the vehicle system and sub-system level to a set of over-arching performance and customer requirements. Rather than focusing on the performance of an individual system, the system is analyzed in terms of the net effect it has on the overall vehicle and other vehicle systems. This detailed level of analysis can only be accomplished through the use of high fidelity computational tools such as Computational Fluid Dynamics (CFD) or Finite Element Analysis (FEA). The utility of the top-down design methodology is investigated through its application to the conceptual and preliminary design of a long-range hypersonic air-breathing vehicle for a hypothetical next generation hypersonic vehicle (NHRV) program. System-level design is demonstrated through the development of the nozzle section of the propulsion system. From this demonstration of the methodology, conclusions are made about the benefits, drawbacks, and cost of using the methodology.

  14. Airbreathing Laser Propulsion Experiments with 1 {mu}m Terawatt Pharos IIILaser: Part 2

    SciTech Connect

    Myrabo, L. N.; Lyons, P. W.; Jones, R. A.; Liu, S.; Manka, C.

    2011-11-10

    This basic research study examines the physics of airbreathing laser propulsion at the extreme flux range of 1-2x10{sup 11} W/cm{sup 2}--within the air breakdown threshold for l {mu}m radiation--using the terawatt Pharos III neodymium-glass pulsed laser. Six different experimental setups were employed using a 34 mm line focus with 66 {mu}m focal waist, positioned near the flat impulse surface. The 2nd Campaign investigated impulse generation with the laser beam focused at grazing incidence across near horizontal target surfaces, with pulse energies ranging from 55 to 186 J, and pulse-widths of 2 to 30 ns FWHM. Laser generated impulse was measured with a horizontal Plexiglas registered ballistic pendulum equipped with either a steel target insert or 0.5 Tesla permanent magnet (NEIT-40), to quantify changes in the momentum coupling coefficient (C{sub M}). Part 2 of this 2-part paper covers Campaign no. 2 results including C{sub M} performance data, and long exposure color photos of LP plasma phenomena.

  15. Airbreathing Laser Propulsion Experiments with 1 {mu}m Terawatt Pharos III Laser: Part 1

    SciTech Connect

    Myrabo, L. N.; Lyons, P. W.; Jones, R. A.; Liu, S.; Manka, C.

    2011-11-10

    This basic research study examines the physics of airbreathing laser propulsion at the extreme flux range of 1-2x10{sup 11} W/cm{sup 2}--within the air breakdown threshold for l {mu}m radiation--using the terawatt PHAROS III neodymium-glass pulsed laser. Six different experimental setups were tested using a 34 mm line focus with 66 {mu}m focal waist, positioned near the flat impulse surface. The first campaign investigated impulse generation with the beam oriented almost normal to the target surface, with energies ranging from 23 to 376 J, and pulses of 5 to 30 ns FWHM. Air breakdown/ plasma dynamics were diagnosed with GOI cameras and color photography. Laser generated impulse was quantified with both vertical pendulums and piezoelectric pressure transducers using the standard performance metric, C{sub M}--the momentum coupling coefficient. Part 1 of this 2-part paper covers Campaign no. 1 results including laser plasma diagnostics, pressure gage and vertical pendulum data.

  16. JANNAF 25Th Airbreathing Propulsion Subcommittee, 37Th Combustion Subcommittee and 1St Modeling and Simulation Subcommittee Joint Meeting. Volume 1

    NASA Technical Reports Server (NTRS)

    Fry, Ronald S. (Editor); Becker, Dorothy L. (Editor)

    2000-01-01

    Contents include the following: 1. Hyper-X program: Propulsion development and verification. 2. GTX program: Airbreathing launch vehicles. 3. Hypersonic technology development: Technology program overviews. Ramjet/scramjet research. 4. Hypersonic test methods: Test medium effects. 5. Advanced propulsion: RBCC engine design and performance assessments. Advanced and combined cycle engine technology.

  17. Static and Hypersonic Experimental Analysis of Impulse Generation in Air-Breathing Laser-Thermal Propulsion

    NASA Astrophysics Data System (ADS)

    Salvador, Israel Irone

    The present research campaign centered on static and hypersonic experiments performed with a two-dimensional, repetitively-pulsed (RP) laser Lightcraft model. The future application of interest for this basic research endeavor is the laser launch of nano- and micro-satellites (i.e., 1-100 kg payloads) into Low Earth Orbit (LEO), at low-cost and "on-demand". This research began with an international collaboration on Beamed Energy Propulsion between the United States Air Force and Brazilian Air Force to conduct experiments at the Henry T. Nagamatsu Laboratory of Aerothermodynamics and Hypersonics (HTN-LAH). The laser propulsion (LP) experiments employed the T3 Hypersonic Shock Tunnel (HST), integrated with twin gigawatt pulsed Lumonics 620-TEA CO2 lasers to produce the required test conditions. Following an introduction of the pulsed laser thermal propulsion concept and a state-of-the-art review of the topic, the principal physical processes are outlined starting from the onset of the laser pulse and subsequent laser-induced air-breakdown, to the expansion and exhaust of the resulting blast wave. After installation of the 254 mm wide, 2D Lightcraft model into the T3 tunnel, static LP tests were performed under quiescent (no-flow) conditions at ambient pressures of 0.06, 0.15, 0.3 and 1 bar, using the T3 test-section/dump-tank as a vacuum chamber. Time-dependent surface pressure distributions were measured over the engine thrust-generating surfaces following laser energy deposition; the delivered impulse and momentum coupling coefficients (Cm) were calculated from that pressure data. A Schlieren visualization system (using a high-speed Cordin digital camera) captured the laser breakdown and blast wave expansion process. The 2D model's Cm performance of 600 to 3000 N/MW was 2.5-5x higher than theoretical projections available in the literature, but indeed in the realm of feasibility for static conditions. Also, these Cm values exceed that for smaller Lightcraft models

  18. Evaluation of an Ejector Ramjet Based Propulsion System for Air-Breathing Hypersonic Flight

    NASA Technical Reports Server (NTRS)

    Thomas, Scott R.; Perkins, H. Douglas; Trefny, Charles J.

    1997-01-01

    A Rocket Based Combined Cycle (RBCC) engine system is designed to combine the high thrust to weight ratio of a rocket along with the high specific impulse of a ramjet in a single, integrated propulsion system. This integrated, combined cycle propulsion system is designed to provide higher vehicle performance than that achievable with a separate rocket and ramjet. The RBCC engine system studied in the current program is the Aerojet strutjet engine concept, which is being developed jointly by a government-industry team as part of the Air Force HyTech program pre-PRDA activity. The strutjet is an ejector-ramjet engine in which small rocket chambers are embedded into the trailing edges of the inlet compression struts. The engine operates as an ejector-ramjet from take-off to slightly above Mach 3. Above Mach 3 the engine operates as a ramjet and transitions to a scramjet at high Mach numbers. For space launch applications the rockets would be re-ignited at a Mach number or altitude beyond which air-breathing propulsion alone becomes impractical. The focus of the present study is to develop and demonstrate a strutjet flowpath using hydrocarbon fuel at up to Mach 7 conditions. Freejet tests of a candidate flowpath for this RBCC engine were conducted at the NASA Lewis Research Center's Hypersonic Tunnel Facility between July and September 1996. This paper describes the engine flowpath and installation, outlines the primary objectives of the program, and describes the overall results of this activity. Through this program 15 full duration tests, including 13 fueled tests were made. The first major achievement was the further demonstration of the HTF capability. The facility operated at conditions up to 1950 K and 7.34 MPa, simulating approximately Mach 6.6 flight. The initial tests were unfueled and focused on verifying both facility and engine starting. During these runs additional aerodynamic appliances were incorporated onto the facility diffuser to enhance starting

  19. An Airbreathing Launch Vehicle Design with Turbine-Based Low-Speed Propulsion and Dual Mode Scramjet High-Speed Propulsion

    NASA Technical Reports Server (NTRS)

    Moses, P. L.; Bouchard, K. A.; Vause, R. F.; Pinckney, S. Z.; Ferlemann, S. M.; Leonard, C. P.; Taylor, L. W., III; Robinson, J. S.; Martin, J. G.; Petley, D. H.

    1999-01-01

    Airbreathing launch vehicles continue to be a subject of great interest in the space access community. In particular, horizontal takeoff and horizontal landing vehicles are attractive with their airplane-like benefits and flexibility for future space launch requirements. The most promising of these concepts involve airframe integrated propulsion systems, in which the external undersurface of the vehicle forms part of the propulsion flowpath. Combining of airframe and engine functions in this manner involves all of the design disciplines interacting at once. Design and optimization of these configurations is a most difficult activity, requiring a multi-discipline process to analytically resolve the numerous interactions among the design variables. This paper describes the design and optimization of one configuration in this vehicle class, a lifting body with turbine-based low-speed propulsion. The integration of propulsion and airframe, both from an aero-propulsive and mechanical perspective are addressed. This paper primarily focuses on the design details of the preferred configuration and the analyses performed to assess its performance. The integration of both low-speed and high-speed propulsion is covered. Structural and mechanical designs are described along with materials and technologies used. Propellant and systems packaging are shown and the mission-sized vehicle weights are disclosed.

  20. CFD Study of Turbo-Ramjet Interactions in Hypersonic Airbreathing Propulsion System

    NASA Technical Reports Server (NTRS)

    Chang, Ing; Hunter, Louis G.

    1996-01-01

    Advanced airbreathing propulsion systems used in Mach 4-6 mission scenarios, usually involve turbo-ramjet configurations. As the engines transition from turbojet to ramjet, there is an operational envelope where both engines operate simultaneously. In the first phase of our study, an over/under nozzle configuration was analyzed. The two plumes from the turbojet and ramjet interact at the end of a common 2-D cowl, where they both reach an approximate Mach 3.0 condition and then jointly expand to Mach 3.6 at the common nozzle exit plane. For the problem analyzed, the turbojet engine operates at a higher nozzle pressure ratio than the ramjet, causes the turbojet plume overpowers the ramjet plume, deflecting it approximately 12 degrees downward and in turn the turbojet plume is deflected 6 degrees upward. In the process, shocks were formed at the deflections and a shear layer formed at the confluence of the two jets. This particular case was experimentally tested and the data were used to compare with a computational fluid dynamics (CFD) study using the PARC2D code. The CFD results were in good agreement with both static pressure distributions on the cowl separator and on nozzle walls. The thrust coefficients were also in reasonable agreement. In addition, inviscid relationships were developed around the confluence point, where the two exhaust jets meet, and these results compared favorably with the CFD results. In the second phase of our study, a 3-D CFD solution was generated to compare with the 2-D solution. The major difference between the 2-D and 3-D solutions was the interaction of the shock waves, generated by the plume interactions, on the sidewall. When a shock wave interacts with a sidewall and sidewall boundary layer, it is called a glancing shock sidewall interaction. These interactions entrain boundary layer flow down the shockline into a vortical flow pattern. The 3-D plots show the streamlines being entrained down the shockline. The pressure of the flow

  1. JANNAF 25th Airbreathing Propulsion Subcommittee, 37th Combustion Subcommittee and 1st Modeling and Simulation Subcommittee Joint Meeting. Volume 1

    NASA Technical Reports Server (NTRS)

    Fry, Ronald S.; Becker, Dorothy L.

    2000-01-01

    Volume I, the first of three volumes, is a compilation of 24 unclassified/unlimited-distribution technical papers presented at the Joint Army-Navy-NASA-Air Force (JANNAF) 25th Airbreathing Propulsion Subcommittee, 37th Combustion Subcommittee and 1st Modeling and Simulation Subcommittee (MSS) meeting held jointly with the 19th Propulsion Systems Hazards Subcommittee. The meeting was held 13-17 November 2000 at the Naval Postgraduate School and Hyatt Regency Hotel, Monterey, California. Topics covered include: a Keynote Address on Future Combat Systems, a review of the new JANNAF Modeling and Simulation Subcommittee, and technical papers on Hyper-X propulsion development and verification; GTX airbreathing launch vehicles; Hypersonic technology development, including program overviews, fuels for advanced propulsion, ramjet and scramjet research, hypersonic test medium effects; and RBCC engine design and performance, and PDE and UCAV advanced and combined cycle engine technologies.

  2. Spaceliner Class Operability Gains Via Combined Airbreathing/ Rocket Propulsion: Summarizing an Operational Assessment of Highly Reusable Space Transports

    NASA Technical Reports Server (NTRS)

    Nix, Michael B.; Escher, William J. d.

    1999-01-01

    In discussing a new NASA initiative in advanced space transportation systems and technologies, the Director of the NASA Marshall Space Flight Center, Arthur G. Stephenson, noted that, "It would use new propulsion technology, air-breathing engine so you don't have to carry liquid oxygen, at least while your flying through the atmosphere. We are calling it Spaceliner 100 because it would be 100 times cheaper, costing $ 100 dollars a pound to orbit." While airbreathing propulsion is directly named, rocket propulsion is also implied by, "... while you are flying through the atmosphere." In-space final acceleration to orbital speed mandates rocket capabilities. Thus, in this informed view, Spaceliner 100 will be predicated on combined airbreathing/rocket propulsion, the technical subject of this paper. Interestingly, NASA's recently concluded Highly Reusable Space Transportation (HRST) study focused on the same affordability goal as that of the Spaceliner 100 initiative and reflected the decisive contribution of combined propulsion as a way of expanding operability and increasing the design robustness of future space transports, toward "aircraft like" capabilities. The HRST study built on the Access to Space Study and the Reusable Launch Vehicle (RLV) development activities to identify and characterize space transportation concepts, infrastructure and technologies that have the greatest potential for reducing delivery cost by another order of magnitude, from $1,000 to $100-$200 per pound for 20,000 lb. - 40.000 lb. payloads to low earth orbit (LEO). The HRST study investigated a number of near-term, far-term, and very far-term launch vehicle concepts including all-rocket single-stage-to-orbit (SSTO) concepts, two-stage-to-orbit (TSTO) concepts, concepts with launch assist, rocket-based combined cycle (RBCC) concepts, advanced expendable vehicles, and more far term ground-based laser powered launchers. The HRST study consisted of preliminary concept studies, assessments

  3. Study of Forebody Injection and Mixing with Application to Hypervelocity Airbreathing Propulsion

    NASA Technical Reports Server (NTRS)

    Axdahl, Erik; Kumar, Ajay; Wilhite, Alan

    2012-01-01

    The use of premixed, shock-induced combustion in the context of a hypervelocity, airbreathing vehicle requires effective injection and mixing of hydrogen fuel and air on the vehicle forebody. Three dimensional computational simulations of fuel injection and mixing from flush-wall and modified ramp and strut injectors are reported in this study. A well-established code, VULCAN, is used to conduct nonreacting, viscous, turbulent simulations on a flat plate at conditions relevant to a Mach 12 flight vehicle forebody. In comparing results of various fuel injection strategies, it is found that strut injection provides the greatest balance of performance between mixing efficiency and stream thrust potential.

  4. Survey of Aerothermodynamics Facilities Useful for the Design of Hypersonic Vehicles Using Air-Breathing Propulsion

    NASA Technical Reports Server (NTRS)

    Arnold, James O.; Deiwert, G. S.

    1997-01-01

    The dream of producing an air-breathing, hydrogen fueled, hypervelocity aircraft has been before the aerospace community for decades. However, such a craft has not yet been realized, even in an experimental form. Despite the simplicity and beauty of the concept, many formidable problems must be overcome to make this dream a reality. This paper summarizes the aero/aerothermodynamic issues that must be addressed to make the dream a reality and discusses how aerothermodynamics facilities and their modem companion, real-gas computational fluid dynamics (CFD), can help solve the problems blocking the way to realizing the dream. The approach of the paper is first to outline the concept of an air-breathing hypersonic vehicle and then discuss the nose-to-tail aerothermodynamics issues and special aerodynamic problems that arise with such a craft. Then the utility of aerothermodynamic facilities and companion CFD analysis is illustrated by reviewing results from recent United States publications wherein these problems have been addressed. Papers selected for the discussion have k e n chosen such that the review will serve to survey important U.S. aero/aerothermodynamic real gas and conventional wind tunnel facilities that are useful in the study of hypersonic, hydrogen propelled hypervelocity vehicles.

  5. Performance analysis of a turbofan as a part of an airbreathing propulsion system for space shuttles

    NASA Astrophysics Data System (ADS)

    Steinebach, D. A.; Kuehl, W.; Gallus, H. E.

    1993-04-01

    This paper presents the results of the design and performance analysis of airbreathing engines for aerospace planes. The analysis is illustrated by introducing an exemplary twin-shaft turbofan engine with post-combustion and bypass-combustion. Some modules of the performance analysis algorithm such as inlet pressure recovery or real gas effects are also presented. The jet engine is designed in view of increasing temperatures at high flight Mach numbers. Hence, the engine design data are dependent on the characteristics of the available materials as well as on the trajectory of the aerospace plane. The results illustrate the strong influence of the real gas effects on the engine thrust particularly in the case of over-stoichiometric combustion of hydrogen. Turbofan engines offer the following advantages in comparison with equivalent turbojet engines: higher thrust performance in supersonic flight range and lower fuel consumption due to operation management of post-combustion and bypass-combustion.

  6. I(sup STAR), NASA's Next Step in Air-Breathing Propulsion for Space Access

    NASA Technical Reports Server (NTRS)

    Hutt, John J.; McArthur, Craig; Cook, Stephen (Technical Monitor)

    2001-01-01

    The United States' National Aeronautics and Space Administration (NASA) has established a strategic plan for future activities in space. A primary goal of this plan is to make drastic improvements in the cost and safety of earth to low-earth-orbit transportation. One approach to achieving this goal is through the development of highly reusable, highly reliable space transportation systems analogous to the commercial airline system. In the year 2000, NASA selected the Rocket Based Combined Cycle (RBCC) engine as the next logical step towards this goal. NASA will develop a complete flight-weight, pump-fed engine system under the Integrated System Test of an Airbreathing Rocket (I(sup STAR)) Project. The objective of this project is develop a reusable engine capable of self-powering a vehicle through the air-augmented rocket, ramjet and scramjet modes required in all RBCC based operational vehicle concepts. The project is currently approved and funded to develop the engine through ground test demonstration. Plans are in place to proceed with flight demonstration pending funding approval. The project is in formulation phase and the Preliminary Requirements Review has been completed. The engine system and vehicle have been selected at the conceptual level. The I(sup STAR) engine concept is based on an air-breathing flowpath downselected from three configurations evaluated in NASA's Advanced Reusable Technology contract. The selected flowpath features rocket thrust chambers integrated into struts separating modular flowpath ducts, a variable geometry inlet, and a thermally choked throat. The engine will be approximately 220 inches long and 79 inches wide and fueled with a hydrocarbon fuel using liquid oxygen as the primary oxidizer candidate. The primary concept for the pump turbine drive is pressure-fed catalyzed hydrogen peroxide. In order to control costs, the flight demonstration vehicle will be launched from a B-52 aircraft. The vehicle concept is based on the Air

  7. An Overview of the NASA FAP Hypersonics Project Airbreathing Propulsion Research

    NASA Technical Reports Server (NTRS)

    Auslender, A. H.; Suder, Kenneth L.; Thomas, Scott R.

    2009-01-01

    The propulsion research portfolio of the National Aeronautics and Space Administration Fundamental Aeronautics Program Hypersonics Project encompasses a significant number of technical tasks that are aligned to achieve mastery and intellectual stewardship of the core competencies in the hypersonic-flight regime. An overall coordinated programmatic and technical effort has been structured to advance the state-of-the-art, via both experimental and analytical efforts. A subset of the entire hypersonics propulsion research portfolio is presented in this overview paper. To this end, two programmatic research disciplines are discussed; namely, (1) the Propulsion Discipline, including three associated research elements: the X-51A partnership, the HIFiRE-2 partnership, and the Durable Combustor Rig, and (2) the Turbine-Based Combine Cycle Discipline, including three associated research elements: the Combined Cycle Engine Large Scale Inlet Mode Transition Experiment, the small-scale Inlet Mode Transition Experiment, and the High-Mach Fan Rig.

  8. Interactions between Flight Dynamics and Propulsion Systems of Air-Breathing Hypersonic Vehicles

    NASA Astrophysics Data System (ADS)

    Dalle, Derek J.

    The development and application of a first-principles-derived reduced-order model called MASIV (Michigan/AFRL Scramjet In Vehicle) for an air-breathing hypersonic vehicle is discussed. Several significant and previously unreported aspects of hypersonic flight are investigated. A fortunate coupling between increasing Mach number and decreasing angle of attack is shown to extend the range of operating conditions for a class of supersonic inlets. Detailed maps of isolator unstart and ram-to-scram transition are shown on the flight corridor map for the first time. In scram mode the airflow remains supersonic throughout the engine, while in ram mode there is a region of subsonic flow. Accurately predicting the transition between these two modes requires models for complex shock interactions, finite-rate chemistry, fuel-air mixing, pre-combustion shock trains, and thermal choking, which are incorporated into a unified framework here. Isolator unstart occurs when the pre-combustion shock train is longer than the isolator, which blocks airflow from entering the engine. Finally, cooptimization of the vehicle design and trajectory is discussed. An optimal control technique is introduced that greatly reduces the number of computations required to optimize the simulated trajectory.

  9. Overview of the development of heat exchangers for use in air-breathing propulsion pre-coolers

    NASA Astrophysics Data System (ADS)

    Murray, James J.; Guha, Abhijit; Bond, Alan

    High pressure heat exchangers used in closed cycle rocket engines and air-breathing propulsion pre-coolers are required to work at very high heat transfer rates. They work with high fluid flow rates and are fabricated from tubes or channels which have small hydraulic diameters. This increases the compactness of the unit and therefore reduces its mass. Novel designs of the manifold are required so that the pressure drop remains within acceptable limit. This paper reports on the progress of research work to investigate the manufacture of such heat exchangers and characterise their performance. The investigations centre on a heat exchanger constructed from tube of 0.4 mm diameter with potential heat transfer coefficients of up to 5000 W/m 2/K. The heat exchanger is subjected to pre-cooler operating conditions of 1000 K simulated air external flow and supercritical cryogenic internal flow. It seeks to validate extrapolations of aerodynamic and heat transfer design data under extreme temperatures and high mass flow rates. Due to the small size of the heat exchanger and the thin walls of the tubes, novel manufacturing methods are required. Work is being done to investigate compatibility of various high temperature brazing materials with thin walled tubes and special manufacturing automation processes to allow cost effective constant-quality fabrication of production units. It is concluded that heat exchangers capable of power transfer rates of up to 1 megawatt per kilogram mass are capable of being manufactured and used operationally. This is a technology where production to satisfy future aerospace demands for single-stage-to-orbit and hypersonic propulsion can be envisaged.

  10. Filtered Mass Density Function for Design Simulation of High Speed Airbreathing Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Givi, P.; Madnia, C. K.; Gicquel, L. Y. M.; Sheikhi, M. R. H.; Drozda, T. G.

    2002-01-01

    The objective of this research is to improve and implement the filtered mass density function (FDF) methodology for large eddy simulation (LES) of high speed reacting turbulent flows. NASA is interested in the design of various components involved in air breathing propulsion systems such as the scramjet. There is a demand for development of robust tools that can aid in the design procedure. The physics of high speed reactive flows is rich with many complexities. LES is regarded as one of the most promising means of simulating turbulent reacting flows.

  11. Modification of NASA Langley 8 foot high temperature tunnel to provide a unique national research facility for hypersonic air-breathing propulsion systems

    NASA Technical Reports Server (NTRS)

    Kelly, H. N.; Wieting, A. R.

    1984-01-01

    A planned modification of the NASA Langley 8-Foot High Temperature Tunnel to make it a unique national research facility for hypersonic air-breathing propulsion systems is described, and some of the ongoing supporting research for that modification is discussed. The modification involves: (1) the addition of an oxygen-enrichment system which will allow the methane-air combustion-heated test stream to simulate air for propulsion testing; and (2) supplemental nozzles to expand the test simulation capability from the current nominal Mach number to 7.0 include Mach numbers 3.0, 4.5, and 5.0. Detailed design of the modifications is currently underway and the modified facility is scheduled to be available for tests of large scale propulsion systems by mid 1988.

  12. Modification of NASA Langley 8 Foot High Temperature Tunnel to provide a unique national research facility for hypersonic air-breathing propulsion systems

    NASA Technical Reports Server (NTRS)

    Kelly, H. N.; Wieting, A. R.

    1984-01-01

    A planned modification of the NASA Langley 8-Foot High Temperature Tunnel to make it a unique national research facility for hypersonic air-breathing propulsion systems is described, and some of the ongoing supporting research for that modification is discussed. The modification involves: (1) the addition of an oxygen-enrichment system which will allow the methane-air combustion-heated test stream to simulate air for propulsion testing; and (2) supplemental nozzles to expand the test simulation capability from the current nominal Mach number to 7.0 include Mach numbers 3.0, 4.5, and 5.0. Detailed design of the modifications is currently underway and the modified facility is scheduled to be available for tests of large scale propulsion systems by mid 1988.

  13. An Overview of 2014 SBIR Phase 1 and Phase 2 Air-Breathing Propulsion

    NASA Technical Reports Server (NTRS)

    Nguyen, Hung D.; Steele, Gynelle C.; Morris, Jessica R.

    2015-01-01

    NASA's Small Business Innovation Research (SBIR) program focuses on technological innovation by investing in development of innovative concepts and technologies to help NASA mission directorates address critical research needs for Agency programs. This report highlights nine of the innovative SBIR 2014 Phase I and Phase II projects that emphasize one of NASA Glenn Research Center's six core competencies-Air-Breathing Propulsion. The technologies cover a wide spectrum of applications such as development of X-ray computed tomography (CT) imaging method for the measurement of complex 3D ice shapes, phased array techniques for low signal-to-noise ratio wind tunnels, compact kinetic mechanisms for petroleum-derived and alternative aviation fuels, and hybrid electric propulsion systems for a multirotor aircraft. Each featured technology describes an innovation, technical objective, and highlights NASA commercial and industrial applications. This report provides as an opportunity for NASA engineers, researchers, and program managers to learn how NASA SBIR technologies could help their programs and projects, and lead to collaborations and partnerships between the small SBIR companies and NASA that would benefit both.

  14. Numerical Simulation of Flow Characteristics of Supersonic Airbreathing Laser Propulsion Vehicle

    NASA Astrophysics Data System (ADS)

    Kim, Sung-Don; Pang, Jun-Sik; Jeung, In-Seuck; Choi, Jeong-Yeol

    2003-05-01

    LITA(Laser-Driven In-Tube Accelerator) is a new device for the propulsion of projectile under high velocity condition. LITA is a little different from other accelerators in that it needs continuous laser source energy for acceleration process. One of the issues for LITA is the optical design of the projectile, because the focusing point of laser behind projectile decides its performance. Laser-supported detonation wave is a main energy source mechanism. Present study shows the performance analysis of LITA using computational fluid dynamics (CFD). Laser power, laser energy, laser frequency, laser focusing point, and projectile base geometry play important roles in LITA's performance. In this research, blast wave produced by explicitly energy input is used.

  15. A US History of Airbreathing/Rocket Combined-Cycle (RBCC) Propulsion for Powering Future Aerospace Transports, with a Look Ahead to the Year 2020

    NASA Technical Reports Server (NTRS)

    Escher, William J. D.

    1999-01-01

    A technohistorical and forward-planning overview of U.S. developments in combined airbreathing/rocket propulsion for advanced aerospace vehicle applications is presented. Such system approaches fall into one of two categories: (1) Combination propulsion systems (separate, non-interacting engines installed), and (2) Combined-Cycle systems. The latter, and main subject, comprises a large family of closely integrated engine types, made up of both airbreathing and rocket derived subsystem hardware. A single vehicle-integrated, multimode engine results, one capable of operating efficiently over a very wide speed and altitude range, atmospherically and in space. While numerous combination propulsion systems have reached operational flight service, combined-cycle propulsion development, initiated ca. 1960, remains at the subscale ground-test engine level of development. However, going beyond combination systems, combined-cycle propulsion potentially offers a compelling set of new and unique capabilities. These capabilities are seen as enabling ones for the evolution of Spaceliner class aerospace transportation systems. The following combined-cycle hypersonic engine developments are reviewed: (1) RENE (rocket engine nozzle ejector), (2) Cryojet and LACE, (3) Ejector Ramjet and its derivatives, (4) the seminal NASA NAS7-377 study, (5) Air Force/Marquardt Hypersonic Ramjet, (6) Air Force/Lockheed-Marquardt Incremental Scramjet flight-test project, (7) NASA/Garrett Hypersonic Research Engine (HRE), (8) National Aero-Space Plane (NASP), (9) all past projects; and such current and planned efforts as (10) the NASA ASTP-ART RBCC project, (11) joint CIAM/NASA DNSCRAM flight test,(12) Hyper-X, (13) Trailblazer,( 14) W-Vehicle and (15) Spaceliner 100. Forward planning programmatic incentives, and the estimated timing for an operational Spaceliner powered by combined-cycle engines are discussed.

  16. Analysis of the Magneto-Hydrodynamic (MHD) Energy Bypass Engine for High-Speed Air-Breathing Propulsion

    NASA Technical Reports Server (NTRS)

    Riggins, David W.

    2002-01-01

    The performance of the MHD energy bypass air-breathing engine for high-speed propulsion is analyzed in this investigation. This engine is a specific type of the general class of inverse cycle engines. In this paper, the general relationship between engine performance (specific impulse and specific thrust) and the overall total pressure ratio through an engine (from inlet plane to exit plane) is first developed and illustrated. Engines with large total pressure decreases, regardless of cause or source, are seen to have exponentially decreasing performance. The ideal inverse cycle engine (of which the MHD engine is a sub-set) is then demonstrated to have a significant total pressure decrease across the engine; this total pressure decrease is cycle-driven, degrades rapidly with energy bypass ratio, and is independent of any irreversibility. The ideal MHD engine (inverse cycle engine with no irreversibility other than that inherent in the MHD work interaction processes) is next examined and is seen to have an additional large total pressure decrease due to MHD-generated irreversibility in the decelerator and the accelerator. This irreversibility mainly occurs in the deceleration process. Both inherent total pressure losses (inverse cycle and MHD irreversibility) result in a significant narrowing of the performance capability of the MHD bypass engine. The fundamental characteristics of MHD flow acceleration and flow deceleration from the standpoint of irreversibility and second-law constraints are next examined in order to clarify issues regarding flow losses and parameter selection in the MM modules. Severe constraints are seen to exist in the decelerator in terms of allowable deceleration Mach numbers and volumetric (length) required for meaningful energy bypass (work interaction). Considerable difficulties are also encountered and discussed due to thermal/work choking phenomena associated with the deceleration process. Lastly, full engine simulations utilizing inlet

  17. Integrated System Test of an Airbreathing Rocket

    NASA Technical Reports Server (NTRS)

    Mack, Gregory; Beaudry, Charles; Ketchum, Andrew; McArthur, J. Craig (Technical Monitor)

    2002-01-01

    This viewgraph presentation provides information on NASA's attempts to develop an air-breathing propulsion in an effort to make future space transportation safer, more reliable and significantly less expensive than today's missions. Spacecraft powered by air-breathing rocket engines would be completely reusable, able to take off and land at airport runways and ready to fly again within days. A radical new engine project is called the Integrated System Tests of an Air-breathing Rocket, or ISTAR.

  18. Airbreathing Acceleration Toward Earth Orbit

    SciTech Connect

    Whitehead, J C

    2007-05-09

    As flight speed increases, aerodynamic drag rises more sharply than the availability of atmospheric oxygen. The ratio of oxygen mass flux to dynamic pressure cannot be improved by changing altitude. The maximum possible speed for airbreathing propulsion is limited by the ratio of air capture area to vehicle drag area, approximately Mach 6 at equal areas. Simulation of vehicle acceleration shows that the use of atmospheric oxygen offers a significant potential for minimizing onboard consumables at low speeds. These fundamental calculations indicate that a practical airbreathing launch vehicle would accelerate to near steady-state speed while consuming only onboard fuel, then transition to rocket propulsion. It is suggested that an aircraft carrying a rocket-propelled vehicle to approximately Mach 5 could be a realistic technical goal toward improving access to orbit.

  19. Air-Breathing Launch Vehicle Technology Being Developed

    NASA Technical Reports Server (NTRS)

    Trefny, Charles J.

    2003-01-01

    Of the technical factors that would contribute to lowering the cost of space access, reusability has high potential. The primary objective of the GTX program is to determine whether or not air-breathing propulsion can enable reusable single-stage-to-orbit (SSTO) operations. The approach is based on maturation of a reference vehicle design with focus on the integration and flight-weight construction of its air-breathing rocket-based combined-cycle (RBCC) propulsion system.

  20. Airbreathing/Rocket Single-Stage-to-Orbit Design Matrix

    NASA Technical Reports Server (NTRS)

    Hunt, James L.

    1995-01-01

    A definitive design/performance study was performed on a single-stage-to-orbit (SSTO) airbreathing propelled orbital vehicle with rocket propulsion augmentation in the Access to Space activities during 1993. A credible reference design was established, but by no means an optimum. The results supported the viability of SSTO airbreathing/rocket vehicles for operational scenarios and indicated compelling reasons to continue to explore the design matrix. This paper will (1) summarize the Access to Space design activity from the SSTO airbreathing/rocket perspective, (2) present an airbreathing/rocket SSTO design matrix established for continued optimization of the design space, and (3) focus on the compelling reasons for airbreathing vehicles in Access to Space scenarios.

  1. Instrumentation for airbreathing propulsion; Proceedings of the Symposium, U.S. Naval Postgraduate School, Monterey, Calif., September 19-21, 1972

    NASA Technical Reports Server (NTRS)

    Fuhs, A. E. (Editor); Kingery, M.

    1974-01-01

    New developments and refinements in measuring techniques used for both ground testing and in-flight control, diagnosis, and monitoring of airbreathing combustors are analyzed in a number of papers. Some of the techniques studied include the application of laser velocimeters for flow measurements; on-the-shaft data systems for rotating engine components; total pressure averaging in pulsating flows; fiber optic and laser digital pressure transducers; holography of nozzles, jets, and spraying systems; application of the Raman effect fo flowfield diagnostics; holography of JP-4 droplets and combusting boron particles; the use of a laser-powered optical proximity probe in advanced turbofan engine development; pyrometry for measurement of surface temperature distribution on a rotating turbine blade; an ultrasonic turbine inlet gas temperature sensor; automatic detection and suppression of inlet buzz; and electrostatic probes for sensing incipient engine failure. Individual items are announced in this issue.

  2. Airbreathing hypersonic vehicle design and analysis methods

    NASA Technical Reports Server (NTRS)

    Lockwood, Mary Kae; Petley, Dennis H.; Hunt, James L.; Martin, John G.

    1996-01-01

    The design, analysis, and optimization of airbreathing hypersonic vehicles requires analyses involving many highly coupled disciplines at levels of accuracy exceeding those traditionally considered in a conceptual or preliminary-level design. Discipline analysis methods including propulsion, structures, thermal management, geometry, aerodynamics, performance, synthesis, sizing, closure, and cost are discussed. Also, the on-going integration of these methods into a working environment, known as HOLIST, is described.

  3. Hypersonic Airbreathing Vehicles/Technologies

    NASA Technical Reports Server (NTRS)

    Hunt, James L.

    1996-01-01

    Hypersonic airbreathing horizontal takeoff and landing (HTOL) vehicles are highly integrated systems involving many advanced technologies. The design environment is variable rich, intricately networked, and sensitivity intensive; as such, it represents a tremendous challenge. Creating a viable design requires addressing three main elements: (1) an understanding of the 'figures of merit' and their relationship, (2) the development of sophisticated configuration discipline prediction methods and a synthesis procedure, and (3) the synergistic integration of advanced technologies across the discipline spectrum. This paper will focus on the vision for hypersonic airbreathing vehicles and the advanced technologies that forge the designs. Airbreathing hypersonics encompass endoatmospheric (airplanes...missiles are a part of the matrix but will not be included in this paper since they are an air force focus) and space access vehicles with speed from Mach 4 up to Mach 25 (orbital). These vehicles can be divided into two classes...cruisers and accelerators. The cruiser designs reflect high lift-to-drag whereas the accelerators reflect low drag per unit inlet capture; thus, the cross section of the accelerator attributes a much larger percentage to propulsion. One of the more design influencing items is fuel. The hydrogen fueled vehicles must be very volumetric efficient to contain the low density fuel and thus tend to be a bit bulgy (more conducive to lifting bodies or wing bodies) whereas with hydrocarbon fueled vehicles, the concern is loading because of the high density fuel; thus, they may tend to be more towards waveriders which are not usually very volumetric efficient. Hydrocarbon fuels (endothermic) are limited in their engine cooling capacity to below Mach 8.

  4. Propulsion

    ERIC Educational Resources Information Center

    Air and Space, 1978

    1978-01-01

    An introductory discussion of aircraft propulsion is included along with diagrams and pictures of piston, turbojet, turboprop, turbofan, and jet engines. Also, a table on chemical propulsion is included. (MDR)

  5. Prospects for future hypersonic air-breathing vehicles

    NASA Technical Reports Server (NTRS)

    Beach, H. L., Jr.; Blankson, Isaiah M.

    1991-01-01

    An overview of the technical progress achieved in key areas of hypersonic airbreathing vehicle development is presented. The context for hypersonic applications is discussed with emphasis placed on technology issues and requirements, particularly for propulsion and technology integration. Attention is given to CFD technology which allows the consideration of configurations and extrapolations to flight conditions that cannot be simulated on the ground.

  6. Integrated System Test of an Airbreathing Rocket (ISTAR)

    NASA Technical Reports Server (NTRS)

    Faulkner, Robert F.; Lyles, Garry (Technical Monitor)

    2001-01-01

    Rocket Based Combined Cycle (RBCC) propulsion system development and ground test is being conducted as part of the NASA Marshall Space Flight Center Integrated System Test of an Airbreathing Rocket (ISTAR) program. Rocketdyne, Aerojet and Pratt & Whitney have teamed as the Rocket Based Combined Cycle Consortium (RBC3) to work the propulsion system development. Each company offered unique RBCC propulsion concepts as candidates for the ISTAR propulsion system. A team of engine contractor, vehicle contractor and NASA representatives reviewed the concepts proposed by each company, reviewed the available data and selected the Aerojet RBCC propulsion system concept as the team propulsion system baseline for the ISTAR program. The ISTAR program is currently in a "Jumpstart" phase for development of the engine system leading to ground test of a thermally and power balanced RBCC propulsion system at Stennis Space Center in 2005. A parallel flight test demonstration of this propulsion system is anticipated to lead to first flight in the 2007 timeframe.

  7. Optimal air-breathing launch vehicle design

    NASA Technical Reports Server (NTRS)

    Hattis, P. D.

    1981-01-01

    A generalized two-point boundary problem methodology, similar to techniques used in deterministic optimal control studies, is applied to the design and flight analysis of a two-stage air-breathing launch vehicle. Simultaneous consideration is given to configuration and trajectory by treating geometry, dynamic discontinuities, and time-dependent flight variables all as controls to be optimized with respect to a single mathematical performance measure. While minimizing fuel consumption, inequality constraints are applied to dynamic pressure and specific force. The optimal system fuel consumption and staging Mach number are found to vary little with changes in the inequality constraints due to substantial geometry and trajectory adjustments. Staging, from an air-breathing first stage to a rocket-powered second stage, consistently occurs near Mach 3.5. The dynamic pressure bound has its most pronounced effects on vehicle geometry, particularly the air-breathing propulsion inlet area, and on the first-stage altitude profile. The specific force has its greatest influence on the second-stage thrust history.

  8. Optimization of Air-Breathing Engine Concept

    NASA Technical Reports Server (NTRS)

    Patnaik, Surya N.; Lavelle, Thomas M.; Hopkins, Dale A.

    1996-01-01

    The design optimization of air-breathing propulsion engine concepts has been accomplished by soft-coupling the NASA Engine Performance Program (NEPP) analyzer with the NASA Lewis multidisciplinary optimization tool COMETBOARDS. Engine problems, with their associated design variables and constraints, were cast as nonlinear optimization problems with thrust as the merit function. Because of the large number of mission points in the flight envelope, the diversity of constraint types, and the overall distortion of the design space; the most reliable optimization algorithm available in COMETBOARDS, when used by itself, could not produce satisfactory, feasible, optimum solutions. However, COMETBOARDS' unique features-which include a cascade strategy, variable and constraint formulations, and scaling devised especially for difficult multidisciplinary applications-successfully optimized the performance of subsonic and supersonic engine concepts. Even when started from different design points, the combined COMETBOARDS and NEPP results converged to the same global optimum solution. This reliable and robust design tool eliminates manual intervention in the design of air-breathing propulsion engines and eases the cycle analysis procedures. It is also much easier to use than other codes, which is an added benefit. This paper describes COMETBOARDS and its cascade strategy and illustrates the capabilities of the combined design tool through the optimization of a high-bypass- turbofan wave-rotor-topped subsonic engine and a mixed-flow-turbofan supersonic engine.

  9. Airbreathing nuclear propulsion: A new look

    NASA Technical Reports Server (NTRS)

    Rom, F. E.

    1971-01-01

    Nuclear-powered air-cushion vehicles using lightweight aircraft-type nuclear powerplants show promise of carrying transoceanic cargo at cost-per-metric-ton-kilometer (cost-per-ton-n mi) rates comparable to railroad rates. These rates are independent of the distance traveled. Cargo rates for nonstop distances of 4000 n mi are expected to be less than one-half those for similar fossil-fueled air-cushion vehicles. For 6000-n mi nonstop distances, the rates are expected to be less than one-sixth as much. There are no fundamental technical reasons why subsonic nuclear aircraft cannot be made to fly successfully if the gross weight is over 1 million lb. Public safety of airborne nuclear powerplants is receiving the greatest attention in low-level experimental and analytical investigations. Idealized model containment vessels which have been impacted on reinforced concrete showed no leaks after impact at velocities to 400 mph. The experiments indicate feasibility of impacting at speeds over 600 mph with no leaks.

  10. Evaluation of some significant issues affecting trajectory and control management for air-breathing hypersonic vehicles

    NASA Technical Reports Server (NTRS)

    Hattis, Philip D.; Malchow, Harvey L.

    1992-01-01

    Horizontal takeoff airbreathing-propulsion launch vehicles require near-optimal guidance and control which takes into account performance sensitivities to atmospheric characteristics while satisfying physically-derived operational constraints. A generic trajectory/control analysis tool that deepens insight into these considerations has been applied to two versions of a winged-cone vehicle model. Information that is critical to the design and trajectory of these vehicles is derived, and several unusual characteristics of the airbreathing propulsion model are shown to have potentially substantial effects on vehicle dynamics.

  11. The microspace launcher: first step to the fully air-breathing space launcher

    NASA Astrophysics Data System (ADS)

    Falempin, F.; Bouchez, M.; Calabro, M.

    2009-09-01

    A possible application for the high-speed air-breathing propulsion is the fully or partially reusable space launcher. Indeed, by combining the high-speed air-breathing propulsion with a conventional rocket engine (combined cycle or combined propulsion system), it should be possible to improve the average installed specific impulse along the ascent trajectory and then make possible more performing launchers and, hopefully, a fully reusable one. During the last 15 years, a lot of system studies have been performed in France on that subject within the framework of different and consecutive programs. Nevertheless, these studies never clearly demonstrated that a space launcher could take advantage of using a combined propulsion system. During last years, the interest to air-breathing propulsion for space application has been revisited. During this review and taking into account technologies development activities already in progress in Europe, clear priorities have been identified regarding a minimum complementary research and technology program addressing specific needs of space launcher application. It was also clearly identified that there is the need to restart system studies taking advantage of recent progress made regarding knowledge, tools, and technology and focusing on more innovative airframe/propulsion system concepts enabling better trade-off between structural efficiency and propulsion system performance. In that field, a fully axisymmetric configuration has been considered for a microspace launcher (10 kg payload). The vehicle is based on a main stage powered by air-breathing propulsion, combined or not with liquid rocket mode. A "kick stage," powered by a solid rocket engine provides the final acceleration. A preliminary design has been performed for different variants: one using a separated booster and a purely air-breathing main stage, a second one using a booster and a main stage combining air-breathing and rocket mode, a third one without separated

  12. Airbreathing Hypersonic Vision-Operational-Vehicles Design Matrix

    NASA Technical Reports Server (NTRS)

    Hunt, James L.; Pegg, Robert J.; Petley, Dennis H.

    1999-01-01

    This paper presents the status of the airbreathing hypersonic airplane and space-access vision-operational-vehicle design matrix, with emphasis on horizontal takeoff and landing systems being, studied at Langley, it reflects the synergies and issues, and indicates the thrust of the effort to resolve the design matrix including Mach 5 to 10 airplanes with global-reach potential, pop-up and dual-role transatmospheric vehicles and airbreathing launch systems. The convergence of several critical systems/technologies across the vehicle matrix is indicated. This is particularly true for the low speed propulsion system for large unassisted horizontal takeoff vehicles which favor turbines and/or perhaps pulse detonation engines that do not require LOX which imposes loading concerns and mission Flexibility restraints.

  13. Airbreathing Hypersonic Vision-Operational-Vehicles Design Matrix

    NASA Technical Reports Server (NTRS)

    Hunt, James L.; Pegg, Robert J.; Petley, Dennis H.

    1999-01-01

    This paper presents the status of the airbreathing hypersonic airplane and space-access vision-operational-vehicle design matrix, with emphasis on horizontal takeoff and landing systems being studied at Langley; it reflects the synergies and issues, and indicates the thrust of the effort to resolve the design matrix including Mach 5 to 10 airplanes with global-reach potential, pop-up and dual-role transatmospheric vehicles and airbreathing launch systems. The convergence of several critical systems/technologies across the vehicle matrix is indicated. This is particularly true for the low speed propulsion system for large unassisted horizontal takeoff vehicles which favor turbines and/or perhaps pulse detonation engines that do not require LOX which imposes loading concerns and mission flexibility restraints.

  14. Aerodynamic characteristics of a series of airbreathing missile configurations

    NASA Technical Reports Server (NTRS)

    Hayes, C.

    1981-01-01

    The results of an experimental program conducted in order to compile a data base useful in the application of airbreathing propulsion to missiles are presented. The configurations investigated used two-dimensional or axisymmetric twin inlets located at three alternative circumferential positions: 90, 115 and 135 deg to the vertical centerline. The effects of a wing located above the inlets and of various tail configurations were investigated, with a view to longitudinal stability/control and lateral-directional stability characteristics. It is noted that of the three tail configurations tested, the 'X' tail showed (1) the most linear pitch-moment curve, (2) control effectiveness, and (3) positive lateral-directional stability.

  15. Prospects for future hypersonic air-breathing vehicles

    NASA Technical Reports Server (NTRS)

    Beach, H. L., Jr.; Blankson, Isaiah M.

    1991-01-01

    The age of hypersonics is (almost) here. This is evident from the amount of activity in the United States, Europe, the USSR and Japan; this activity is a reflection of technical progress in key areas which will enable new vehicle systems, as well as renewed interest in the utilization of these systems. The current situation, at least in the United States, is the product of an interesting history which is briefly reviewed here. The context for hypersonic applications is discussed, but the emphasis is on hypersonic technology issues and needs, particularly for propulsion and technology integration. The paper concludes with prospects for accomplishing the objective of air-breathing hypersonic vehicle systems.

  16. An Air-Breathing Launch Vehicle Concept for Single-Stage-to-Orbit

    NASA Technical Reports Server (NTRS)

    Trefny, Charles J.

    1999-01-01

    The "Trailblazer" is a 300-lb payload, single-stage-to-orbit launch vehicle concept that uses air-breathing propulsion to reduce the required propellant fraction. The integration of air-breathing propulsion is done considering performance, structural and volumetric efficiency, complexity, and design risk. The resulting configuration is intended to be viable using near-term materials and structures. The aeropropulsion performance goal for the Trailblazer launch vehicle is an equivalent effective specific impulse (I*) of 500 sec. Preliminary analysis shows that this requires flight in the atmosphere to about Mach 10, and that the gross lift-off weight is 130,000 lb. The Trailblazer configuration and proposed propulsion system operating modes are described. Preliminary performance results are presented, and key technical issues are highlighted. An overview of the proposed program plan is given.

  17. Air-Breathing Rocket Engines

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This photograph depicts an air-breathing rocket engine prototype in the test bay at the General Applied Science Lab facility in Ronkonkoma, New York. Air-breathing engines, known as rocket based, combined-cycle engines, get their initial take-off power from specially designed rockets, called air-augmented rockets, that boost performance about 15 percent over conventional rockets. When the vehicle's velocity reaches twice the speed of sound, the rockets are turned off and the engine relies totally on oxygen in the atmosphere to burn hydrogen fuel, as opposed to a rocket that must carry its own oxygen, thus reducing weight and flight costs. Once the vehicle has accelerated to about 10 times the speed of sound, the engine converts to a conventional rocket-powered system to propel the craft into orbit or sustain it to suborbital flight speed. NASA's Advanced Space Transportation Program at Marshall Space Flight Center, along with several industry partners and collegiate forces, is developing this technology to make space transportation affordable for everyone from business travelers to tourists. The goal is to reduce launch costs from today's price tag of $10,000 per pound to only hundreds of dollars per pound. NASA's series of hypersonic flight demonstrators currently include three air-breathing vehicles: the X-43A, X-43B and X-43C.

  18. Preliminary Sizing of an Hypersonic Airbreathing Airliner

    NASA Astrophysics Data System (ADS)

    Ingenito, Antonella; Gulli, Stefano; Bruno, Claudio

    The purpose of this paper is to identify, for given technology levels (TRL) and mission requirements, those parameters that are critical for preliminary sizing of a hypersonic airbreathing airliner. Mission requirements will dictate a solution space of possible vehicle architecture capable of meeting cruise conditions as well as of taking-off (TO) and landing. In practice, once defined a range of cruise vehicle architectures, constraints are imposed (as to all passenger airliners), such as: 1. take off (=TO) and landing distance (so-called field length, FL): FL no longer than for the B-747-400, or 10000 ft; 2. completing TO with one engine off; 3. max acceleration at TO and climb-out (CO) = 0.4 g; 4. Hydrogen fuel (Meeting NOx emission limits (EINOx) is a further constraint not discussed in this paper). These constraints enable focusing on a realistic design out of the broad range of vehicles capable of performing the given mission. Thus a realistic vehicle must not only integrate aerodynamics and propulsion system; in fact, it is the result of many iterations in the design space, until performance and constraints are successfully achieved and met. The Gross Weight at Take Off (TOGW) was deliberately discarded as a constraint, based on Previous studies by Czysz. Typically, limiting from the beginning the TOGW leads to a vicious spiral where weight and propulsion system requirements keep growing, eventually denying convergence. In designing passenger airliners, in fact, it is the payload that is assumed fixed from the start, not the total weight. A parametric analysis of the hypersonic vehicle architecture is presented: in particular, optimal size, weight and geometrical shape are defined for different mission requirements. This analysis has shown that, it is possible to define a range of possible successful solutions for the European LAPCAT II project.

  19. Airbreathing engines for space shuttle

    NASA Technical Reports Server (NTRS)

    Glassman, A. J.; Stewart, W. L.; Nosek, S. M.

    1972-01-01

    The requirements imposed on the airbreathing engines by the shuttle mission and some results from engine design studies are discussed. In particular, some of the engine system weight study results are presented, potential problem areas and required engine modifications are identified, and testing requirements for a development and qualification program are discussed. The engines of interest for the shuttle are engines that are currently being developed for other applicatons. The potential problems, engine modifications, and testing requirements result primarily from the new environments associated with launch, space residence, and reentry.

  20. Performance Validation Approach for the GTX Air-Breathing Launch Vehicle

    NASA Technical Reports Server (NTRS)

    Trefny, Charles J.; Roche, Joseph M.

    2002-01-01

    The primary objective of the GTX effort is to determine whether or not air-breathing propulsion can enable a launch vehicle to achieve orbit in a single stage. Structural weight, vehicle aerodynamics, and propulsion performance must be accurately known over the entire flight trajectory in order to make a credible assessment. Structural, aerodynamic, and propulsion parameters are strongly interdependent, which necessitates a system approach to design, evaluation, and optimization of a single-stage-to-orbit concept. The GTX reference vehicle serves this purpose, by allowing design, development, and validation of components and subsystems in a system context. The reference vehicle configuration (including propulsion) was carefully chosen so as to provide high potential for structural and volumetric efficiency, and to allow the high specific impulse of air-breathing propulsion cycles to be exploited. Minor evolution of the configuration has occurred as analytical and experimental results have become available. With this development process comes increasing validation of the weight and performance levels used in system performance determination. This paper presents an overview of the GTX reference vehicle and the approach to its performance validation. Subscale test rigs and numerical studies used to develop and validate component performance levels and unit structural weights are outlined. The sensitivity of the equivalent, effective specific impulse to key propulsion component efficiencies is presented. The role of flight demonstration in development and validation is discussed.

  1. Propulsion concepts for high speed aircraft

    NASA Technical Reports Server (NTRS)

    Stull, F. D.; Jones, R. A.; Zima, W. P.

    1975-01-01

    A wide variety of potentially useful and effective airbreathing aircraft have been postulated to operate at speeds in excess of Mach 3.0 by NASA and the USAF. These systems include hydrogen-fueled transports of interest for very long ranges and airbreathing launch vehicles which are aircraft-type first stage candidates for future space shuttle systems. Other high speed airbreathing systems for possible future military applications include advanced reconnaissance and fighter/interceptor type aircraft and strategic systems. This paper presents (1) a chronology of Air Force technical activity on future propulsion concepts, (2) a status report on NASA research on scramjet technology for future systems which may require speeds above Mach 5, and (3) a description of a research vehicle by which advanced propulsion technology and other technologies related to high speed can be demonstrated.

  2. Aerodynamic characteristics of a series of airbreathing missile configurations

    NASA Technical Reports Server (NTRS)

    Hayes, C.

    1981-01-01

    Due to the interest in the application of airbreathing propulsion to missiles and the lack of a suitable data base, an experimental program has been conducted to contribute to such a data base. The configurations investigated were with twin-inlets, either two-dimensional or axisymmetric, each located at three circumferential locations. The effects of a wing located above the inlets and of tail configuration were investigated. Longitudinal stability and control and lateral-directional stability were included in the data obtained. This paper presents a summary of the program and some of the results obtained. Certain trends of the data, as well as problem areas, are discussed. Due to the large volume of data obtained, a detailed analysis is not presented.

  3. Affordable Flight Demonstration of the GTX Air-Breathing SSTO Vehicle Concept

    NASA Technical Reports Server (NTRS)

    Krivanek, Thomas M.; Roche, Joseph M.; Riehl, John P.; Kosareo, Daniel N.

    2002-01-01

    The rocket based combined cycle (RBCC) powered single-stage-to-orbit (SSTO) reusable launch vehicle has the potential to significantly reduce the total cost per pound for orbital payload missions. To validate overall system performance, a flight demonstration must be performed. This paper presents an overview of the first phase of a flight demonstration program for the GTX SSTO vehicle concept. Phase 1 will validate the propulsion performance of the vehicle configuration over the supersonic and hypersonic airbreathing portions of the trajectory. The focus and goal of Phase 1 is to demonstrate the integration and performance of the propulsion system flowpath with the vehicle aerodynamics over the air-breathing trajectory. This demonstrator vehicle will have dual mode ramjet/scramjets, which include the inlet, combustor, and nozzle with geometrically scaled aerodynamic surface outer mold lines (OML) defining the forebody, boundary layer diverter, wings, and tail. The primary objective of this study is to demonstrate propulsion system performance and operability including the ram to scram transition, as well as to validate vehicle aerodynamics and propulsion airframe integration. To minimize overall risk and development cost the effort will incorporate proven materials, use existing turbomachinery in the propellant delivery systems, launch from an existing unmanned remote launch facility, and use basic vehicle recovery techniques to minimize control and landing requirements. A second phase would demonstrate propulsion performance across all critical portions of a space launch trajectory (lift off through transition to all-rocket) integrated with flight-like vehicle systems.

  4. Power Reduction of the Air-Breathing Hall-Effect Thruster

    NASA Astrophysics Data System (ADS)

    Kim, Sungrae

    Electric propulsion system is spotlighted as the next generation space propulsion system due to its benefits; one of them is specific impulse. While there are a lot of types in electric propulsion system, Hall-Effect Thruster, one of electric propulsion system, has higher thrust-to-power ratio and requires fewer power supplies for operation in comparison to other electric propulsion systems, which means it is optimal for long space voyage. The usual propellant for Hall-Effect Thruster is Xenon and it is used to be stored in the tank, which may increase the weight of the thruster. Therefore, one theory that uses the ambient air as a propellant has been proposed and it is introduced as Air-Breathing Hall-Effect Thruster. Referring to the analysis on Air-Breathing Hall-Effect Thruster, the goal of this paper is to reduce the power of the thruster so that it can be applied to real mission such as satellite orbit adjustment. To reduce the power of the thruster, two assumptions are considered. First one is changing the altitude for the operation, while another one is assuming the alpha value that is electron density to ambient air density. With assumptions above, the analysis was done and the results are represented. The power could be decreased to 10s˜1000s with the assumptions. However, some parameters that do not satisfy the expectation, which would be the question for future work, and it will be introduced at the end of the thesis.

  5. Rocket-Based Combined-Cycle (RBCC) Propulsion Technology Workshop. Tutorial session

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The goal of this workshop was to illuminate the nation's space transportation and propulsion engineering community on the potential of hypersonic combined cycle (airbreathing/rocket) propulsion systems for future space transportation applications. Four general topics were examined: (1) selections from the expansive advanced propulsion archival resource; (2) related propulsion systems technical backgrounds; (3) RBCC engine multimode operations related subsystem background; and (4) focused review of propulsion aspects of current related programs.

  6. Airbreathing combined cycle engine systems

    NASA Technical Reports Server (NTRS)

    Rohde, John

    1992-01-01

    The Air Force and NASA share a common interest in developing advanced propulsion systems for commercial and military aerospace vehicles which require efficient acceleration and cruise operation in the Mach 4 to 6 flight regime. The principle engine of interest is the turboramjet; however, other combined cycles such as the turboscramjet, air turborocket, supercharged ejector ramjet, ejector ramjet, and air liquefaction based propulsion are also of interest. Over the past months careful planning and program implementation have resulted in a number of development efforts that will lead to a broad technology base for those combined cycle propulsion systems. Individual development programs are underway in thermal management, controls materials, endothermic hydrocarbon fuels, air intake systems, nozzle exhaust systems, gas turbines and ramjet ramburners.

  7. Flight testing of airbreathing hypersonic vehicles

    NASA Technical Reports Server (NTRS)

    Hicks, John W.

    1993-01-01

    Using the scramjet engine as the prime example of a hypersonic airbreathing concept, this paper reviews the history of and addresses the need for hypersonic flight tests. It also describes how such tests can contribute to the development of airbreathing technology. Aspects of captive-carry and free-flight concepts are compared. An incremental flight envelope expansion technique for manned flight vehicles is also described. Such critical issues as required instrumentation technology and proper scaling of experimental devices are addressed. Lastly, examples of international flight test approaches, existing programs, or concepts currently under study, development, or both, are given.

  8. CFD for hypersonic propulsion

    NASA Technical Reports Server (NTRS)

    Povinelli, Louis A.

    1990-01-01

    An overview is given of research activity on the application of computational fluid dynamics (CDF) for hypersonic propulsion systems. After the initial consideration of the highly integrated nature of air-breathing hypersonic engines and airframe, attention is directed toward computations carried out for the components of the engine. A generic inlet configuration is considered in order to demonstrate the highly three dimensional viscous flow behavior occurring within rectangular inlets. Reacting flow computations for simple jet injection as well as for more complex combustion chambers are then discussed in order to show the capability of viscous finite rate chemical reaction computer simulations. Finally, the nozzle flow fields are demonstrated, showing the existence of complex shear layers and shock structure in the exhaust plume. The general issues associated with code validation as well as the specific issue associated with the use of CFD for design are discussed. A prognosis for the success of CFD in the design of future propulsion systems is offered.

  9. CFD for hypersonic propulsion

    NASA Technical Reports Server (NTRS)

    Povinelli, Louis A.

    1991-01-01

    An overview is given of research activity on the application of computational fluid dynamics (CDF) for hypersonic propulsion systems. After the initial consideration of the highly integrated nature of air-breathing hypersonic engines and airframe, attention is directed toward computations carried out for the components of the engine. A generic inlet configuration is considered in order to demonstrate the highly three dimensional viscous flow behavior occurring within rectangular inlets. Reacting flow computations for simple jet injection as well as for more complex combustion chambers are then discussed in order to show the capability of viscous finite rate chemical reaction computer simulations. Finally, the nozzle flow fields are demonstrated, showing the existence of complex shear layers and shock structure in the exhaust plume. The general issues associated with code validation as well as the specific issue associated with the use of CFD for design are discussed. A prognosis for the success of CFD in the design of future propulsion systems is offered.

  10. JTEC panel report on space and transatmospheric propulsion technology

    NASA Technical Reports Server (NTRS)

    Shelton, Duane

    1990-01-01

    An assessment of Japan's current capabilities in the areas of space and transatmospheric propulsion is presented. The report focuses primarily upon Japan's programs in liquid rocket propulsion and in propulsion for spaceplanes and related transatmospheric areas. It also includes brief reference to Japan's solid rocket programs, as well as to supersonic air-breathing propulsion efforts that are just getting underway. The results are based upon the findings of a panel of U.S. engineers made up of individuals from academia, government, and industry, and are derived from a review of a broad array of the open literature, combined with visits to the primary propulsion laboratories and development agencies in Japan.

  11. Fitting aerodynamics and propulsion into the puzzle

    NASA Technical Reports Server (NTRS)

    Johnston, Patrick J.; Whitehead, Allen H., Jr.; Chapman, Gary T.

    1987-01-01

    The development of an airbreathing single-stage-to-orbit vehicle, in particular the problems of aerodynamics and propulsion integration, is examined. The boundary layer transition on constant pressure surfaces at hypersonic velocities, and the effects of noise on the transition are investigated. The importance of viscosity, real-gas effects, and drag at hypersonic speeds is discussed. A propulsion system with sufficient propulsive lift to enhance the performance of the vehicle is being developed. The difficulties of engine-airframe integration are analyzed.

  12. The Design of Future Airbreathing Engine Systems within an Intelligent Synthesis Environment

    NASA Technical Reports Server (NTRS)

    Malone, J. B.; Housner, J. M.; Lytle, J. K.

    1999-01-01

    This paper describes a new Initiative proposed by the National Aeronautics and Space Administration (NASA). The purpose of this initiative is to develop a future design environment for engineering and science mission synthesis for use by NASA scientists and engineers. This new initiative is called the Intelligent Synthesis Environment (ISE). The paper describes the mission of NASA, future aerospace system characteristics, the current engineering design process, the ISE concept, and concludes with a description of possible ISE applications for the decision of air-breathing propulsion systems.

  13. Supersonic Air-Breathing Stage For Commercial Launch Rocket

    NASA Technical Reports Server (NTRS)

    Martin, James A.

    1993-01-01

    Concept proposed to expand use of air-breathing, reusable stages to put more payload into orbit at less cost. Stage with supersonic air-breathing engines added to carry expendable stages from subsonic airplane to supersonic velocity. Carry payload to orbit. Expendable stages and payload placed in front of supersonic air-breathing stage. After releasing expendable stages, remotely piloted supersonic air-breathing stage returns to takeoff site and land for reuse. New concept extends use of low-cost reusable hardware and increases payload delivered from B-52.

  14. Air-breathing Rocket Engine Test

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This Quick Time movie depicts the Rocketdyne static test of an air-breathing rocket. Air-breathing engines, known as rocket based, combined-cycle engines, get their initial take-off power from specially designed rockets, called air-augmented rockets, that boost performance about 15 percent over conventional rockets. When the vehicle's velocity reaches twice the speed of sound, the rockets are turned off and the engine relies totally on oxygen in the atmosphere to burn hydrogen fuel, as opposed to a rocket that must carry its own oxygen, thus reducing weight and flight costs. Once the vehicle has accelerated to about 10 times the speed of sound, the engine converts to a conventional rocket-powered system to propel the craft into orbit or sustain it to suborbital flight speed. NASA's advanced Transportation Program at the Marshall Space Flight Center, along with several industry partners and collegiate forces, is developing this technology to make space transportation affordable for everyone from business travelers to tourists. The goal is to reduce launch costs from today's price tag of $10,000 per pound to only hundreds of dollars per pound. NASA's series of hypersonic flight demonstrators currently include three air-breathing vehicles: the X-43A, X-43B and X-43C.

  15. Airframe Research and Technology for Hypersonic Airbreathing Vehicles

    NASA Technical Reports Server (NTRS)

    Glass, David E.; Merski, N. Ronald; Glass, Christopher E.

    2002-01-01

    The Hypersonics Investment Area (HIA) within NASA's Advanced Space Transportation Program (ASTP) has the responsibility to develop hypersonic airbreathing vehicles for access to space. The Airframe Research and Technology (AR and T) Project, as one of six projects in the HIA, will push the state-of-the-art in airframe and vehicle systems for low-cost, reliable, and safe space transportation. The individual technologies within the project are focused on advanced, breakthrough technologies in airframe and vehicle systems and cross-cutting activities that are the basis for improvements in these disciplines. Both low and medium technology readiness level (TRL) activities are being pursued. The key technical areas that will be addressed by the project include analysis and design tools, integrated vehicle health management (IVHM), composite (polymer, metal, and ceramic matrix) materials development, thermal/structural wall concepts, thermal protection systems, seals, leading edges, aerothermodynamics, and airframe/propulsion flowpath technology. Each of the technical areas or sub-projects within the Airframe R and T Project is described in this paper.

  16. Thermodynamic Cycle Analysis of Magnetohydrodynamic-Bypass Hypersonic Airbreathing Engines

    NASA Technical Reports Server (NTRS)

    Litchford, R. J.; Cole, J. W.; Bityurin, V. A.; Lineberry, J. T.

    2000-01-01

    The prospects for realizing a magnetohydrodynamic (MHD) bypass hypersonic airbreathing engine are examined from the standpoint of fundamental thermodynamic feasibility. The MHD-bypass engine, first proposed as part of the Russian AJAX vehicle concept, is based on the idea of redistributing energy between various stages of the propulsion system flow train. The system uses an MHD generator to extract a portion of the aerodynamic heating energy from the inlet and an MHD accelerator to reintroduce this power as kinetic energy in the exhaust stream. In this way, the combustor entrance Mach number can be limited to a specified value even as the flight Mach number increases. Thus, the fuel and air can be efficiently mixed and burned within a practical combustor length, and the flight Mach number operating envelope can be extended. In this paper, we quantitatively assess the performance potential and scientific feasibility of MHD-bypass engines using a simplified thermodynamic analysis. This cycle analysis, based on a thermally and calorically perfect gas, incorporates a coupled MHD generator-accelerator system and accounts for aerodynamic losses and thermodynamic process efficiencies in the various engin components. It is found that the flight Mach number range can be significantly extended; however, overall performance is hampered by non-isentropic losses in the MHD devices.

  17. Thermodynamic Cycle Analysis of Magnetohydrodynamic-Bypass Airbreathing Hypersonic Engines

    NASA Technical Reports Server (NTRS)

    Litchford, Ron J.; Bityurin, Valentine A.; Lineberry, John T.

    1999-01-01

    Established analyses of conventional ramjet/scramjet performance characteristics indicate that a considerable decrease in efficiency can be expected at off-design flight conditions. This can be explained, in large part, by the deterioration of intake mass flow and limited inlet compression at low flight speeds and by the onset of thrust degradation effects associated with increased burner entry temperature at high flight speeds. In combination, these effects tend to impose lower and upper Mach number limits for practical flight. It has been noted, however, that Magnetohydrodynamic (MHD) energy management techniques represent a possible means for extending the flight Mach number envelope of conventional engines. By transferring enthalpy between different stages of the engine cycle, it appears that the onset of thrust degradation may be delayed to higher flight speeds. Obviously, the introduction of additional process inefficiencies is inevitable with this approach, but it is believed that these losses are more than compensated through optimization of the combustion process. The fundamental idea is to use MHD energy conversion processes to extract and bypass a portion of the intake kinetic energy around the burner. We refer to this general class of propulsion system as an MHD-bypass engine. In this paper, we quantitatively assess the performance potential and scientific feasibility of MHD-bypass airbreathing hypersonic engines using ideal gasdynamics and fundamental thermodynamic principles.

  18. Ascent performance of an air-breathing horizontal-takeoff launch vehicle

    NASA Technical Reports Server (NTRS)

    Powell, Richard W.; Shaughnessy, John D.; Cruz, Christopher I.; Naftel, J. C.

    1991-01-01

    Simulations are conducted to investigate a proposed NASA launch vehicle that is fully reusable, takes off horizontally, and uses airbreathing propulsion in a single stage. The propulsion model is based on a cycle analysis method, and the vehicle is assumed to be a rigid structure with distributed fuel, operating under a range of atmospheric conditions. The program to optimize simulated trajectories (POST) is modified to include a predictor-corrector guidance capability and then used to generate the trajectories. Significant errors are encountered during the unpowered coast phase due to uncertainty in the atmospheric density profile. The amount of ascent propellant needed is shown to be directly related to the thrust-vector angle and the location of the center of gravity of the vehicle because of the importance of aim-drag losses to total ideal velocity.

  19. Affordable Flight Demonstration of the GTX Air-Breathing SSTO Vehicle Concept

    NASA Technical Reports Server (NTRS)

    Krivanek, Thomas M.; Roche, Joseph M.; Riehl, John P.; Kosareo, Daniel N.

    2003-01-01

    The rocket based combined cycle (RBCC) powered single-stage-to-orbit (SSTO) reusable launch vehicle has the potential to significantly reduce the total cost per pound for orbital payload missions. To validate overall system performance, a flight demonstration must be performed. This paper presents an overview of the first phase of a flight demonstration program for the GTX SSTO vehicle concept. Phase 1 will validate the propulsion performance of the vehicle configuration over the supersonic and hypersonic air- breathing portions of the trajectory. The focus and goal of Phase 1 is to demonstrate the integration and performance of the propulsion system flowpath with the vehicle aerodynamics over the air-breathing trajectory. This demonstrator vehicle will have dual mode ramjetkcramjets, which include the inlet, combustor, and nozzle with geometrically scaled aerodynamic surface outer mold lines (OML) defining the forebody, boundary layer diverter, wings, and tail. The primary objective of this study is to demon- strate propulsion system performance and operability including the ram to scram transition, as well as to validate vehicle aerodynamics and propulsion airframe integration. To minimize overall risk and develop ment cost the effort will incorporate proven materials, use existing turbomachinery in the propellant delivery systems, launch from an existing unmanned remote launch facility, and use basic vehicle recovery techniques to minimize control and landing requirements. A second phase would demonstrate propulsion performance across all critical portions of a space launch trajectory (lift off through transition to all-rocket) integrated with flight-like vehicle systems.

  20. Structural Sizing of a 25,000-lb Payload, Air-breathing Launch Vehicle for Single-stage-to-orbit

    NASA Technical Reports Server (NTRS)

    Roche, Joseph M.; Kosareo, Daniel N.

    2001-01-01

    In support of NASA's Air-Breathing Launch Vehicle (ABLV) study, a 25,000-lb payload version of the GTX (formerly Trailblazer) reference vehicle concept was developed. The GTX is a vertical lift-off, reusable, single-stage-to-orbit launch vehicle concept that uses hypersonic air-breathing propulsion in a rocket-based combined-cycle (RBCC) propulsion system to reduce the required propellant fraction. To achieve this goal the vehicle and propulsion system must be well integrated both aerodynamically and structurally to reduce weight. This study demonstrates the volumetric and structural efficiency of a vertical takeoff, horizontal landing, hypersonic vehicle with a circular cross section. A departure from the lifting body concepts, this design philosophy is even extended to the engines, which have semicircular nacelles symmetrically mounted on the vehicle. Material candidates with a potential for lightweight and simplicity have been selected from a set of near term technologies (five to ten years). To achieve the mission trajectory, preliminary weight estimates show the vehicle's gross lift-off weight is 1.26 x 10(exp 6) lb. The structural configuration of the GTX vehicle and its propulsion system are described. The vehicle design benefits are presented, and key technical issues are highlighted.

  1. Structural Sizing of a 25,000-lb Payload, Air-Breathing Launch Vehicle For Single-Stage-To-Orbit

    NASA Technical Reports Server (NTRS)

    Roche, Joseph M.; Kosareo, Daniel N.; Palac, Don (Technical Monitor)

    2000-01-01

    In support of NASA's Air-Breathing Launch Vehicle (ABLV) study, a 25,000-lb payload version of the GTX (formerly Trailblazer) reference vehicle concept was developed. The GTX is a vertical lift-off, reusable, single-stage-to-orbit launch vehicle concept that uses hypersonic air-breathing propulsion in a rocket-based combined-cycle (RBCC) propulsion system to reduce the required propellant fraction. To achieve this goal the vehicle and propulsion system must be well integrated both aerodynamically and structurally to reduce weight. This study demonstrates the volumetric and structural efficiency of a vertical takeoff, horizontal landing, hypersonic vehicle with a circular cross section. A departure from the lifting body concepts, this design philosophy is even extended to the engines, which have semicircular nacelles symmetrically mounted on the vehicle. Material candidates with a potential for lightweight and simplicity have been selected from a set of near term technologies (5 to 10 years). To achieve the mission trajectory, preliminary weight estimates show the vehicle's gross lift-off weight is 1.26 x 10(exp 6) lb. The structural configuration of the GTX vehicle and its propulsion system are described. The vehicle design benefits are presented, and key technical issues are highlighted.

  2. Air-Breathing Rocket Engine Test

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This photograph depicts an air-breathing rocket engine that completed an hour or 3,600 seconds of testing at the General Applied Sciences Laboratory in Ronkonkoma, New York. Referred to as ARGO by its design team, the engine is named after the mythological Greek ship that bore Jason and the Argonauts on their epic voyage of discovery. Air-breathing engines, known as rocket based, combined-cycle engines, get their initial take-off power from specially designed rockets, called air-augmented rockets, that boost performance about 15 percent over conventional rockets. When the vehicle's velocity reaches twice the speed of sound, the rockets are turned off and the engine relies totally on oxygen in the atmosphere to burn hydrogen fuel, as opposed to a rocket that must carry its own oxygen, thus reducing weight and flight costs. Once the vehicle has accelerated to about 10 times the speed of sound, the engine converts to a conventional rocket-powered system to propel the craft into orbit or sustain it to suborbital flight speed. NASA's Advanced SpaceTransportation Program at Marshall Space Flight Center, along with several industry partners and collegiate forces, is developing this technology to make space transportation affordable for everyone from business travelers to tourists. The goal is to reduce launch costs from today's price tag of $10,000 per pound to only hundreds of dollars per pound. NASA's series of hypersonic flight demonstrators currently include three air-breathing vehicles: the X-43A, X-43B and X-43C.

  3. Hypersonic airbreathing vehicle visions and enhancing technologies

    SciTech Connect

    Hunt, J.L.; Lockwood, M.K.; Petley, D.H.; Pegg, R.J.

    1997-01-01

    This paper addresses the visions for hypersonic airbreathing vehicles and the advanced technologies that forge and enhance the designs. The matrix includes space access vehicles (single-stage-to-orbit (SSTO), two-stage-to-orbit (2STO) and three-stage-to-orbit (3STO)) and endoatmospheric vehicles (airplanes{emdash}missiles are omitted). The characteristics, the performance potential, the technologies and the synergies will be discussed. A common design constraint is that all vehicles (space access and endoatmospheric) have enclosed payload bays. {copyright} {ital 1997 American Institute of Physics.}

  4. Numerical Propulsion System Simulation

    NASA Technical Reports Server (NTRS)

    Naiman, Cynthia

    2006-01-01

    The NASA Glenn Research Center, in partnership with the aerospace industry, other government agencies, and academia, is leading the effort to develop an advanced multidisciplinary analysis environment for aerospace propulsion systems called the Numerical Propulsion System Simulation (NPSS). NPSS is a framework for performing analysis of complex systems. The initial development of NPSS focused on the analysis and design of airbreathing aircraft engines, but the resulting NPSS framework may be applied to any system, for example: aerospace, rockets, hypersonics, power and propulsion, fuel cells, ground based power, and even human system modeling. NPSS provides increased flexibility for the user, which reduces the total development time and cost. It is currently being extended to support the NASA Aeronautics Research Mission Directorate Fundamental Aeronautics Program and the Advanced Virtual Engine Test Cell (AVETeC). NPSS focuses on the integration of multiple disciplines such as aerodynamics, structure, and heat transfer with numerical zooming on component codes. Zooming is the coupling of analyses at various levels of detail. NPSS development includes capabilities to facilitate collaborative engineering. The NPSS will provide improved tools to develop custom components and to use capability for zooming to higher fidelity codes, coupling to multidiscipline codes, transmitting secure data, and distributing simulations across different platforms. These powerful capabilities extend NPSS from a zero-dimensional simulation tool to a multi-fidelity, multidiscipline system-level simulation tool for the full development life cycle.

  5. Space and transatmospheric propulsion technology

    NASA Technical Reports Server (NTRS)

    Merkle, Charles; Stangeland, Maynard L.; Brown, James R.; Mccarty, John P.; Povinelli, Louis A.; Northam, G. Burton; Zukoski, Edward E.

    1994-01-01

    This report focuses primarily on Japan's programs in liquid rocket propulsion and propulsion for spaceplane and related transatmospheric areas. It refers briefly to Japan's solid rocket programs and to new supersonic air-breathing propulsion efforts. The panel observed that the Japanese had a carefully thought-out plan, a broad-based program, and an ambitious but achievable schedule for propulsion activity. Japan's overall propulsion program is behind that of the United States at the time of this study, but the Japanese are gaining rapidly. The Japanese are at the forefront in such key areas as advanced materials, enjoying a high level of project continuity and funding. Japan's space program has been evolutionary in nature, while the U.S. program has emphasized revolutionary advances. Projects have typically been smaller in Japan than in the United States, focusing on incremental advances in technology, with an excellent record of applying proven technology to new projects. This evolutionary approach, coupled with an ability to take technology off the shelf from other countries, has resulted in relatively low development costs, rapid progress, and enhanced reliability. Clearly Japan is positioned to be a world leader in space and transatmospheric propulsion technology by the year 2000.

  6. SPE propulsion electrolyzer for NASA's integrated propulsion test article

    NASA Astrophysics Data System (ADS)

    1991-08-01

    Hamilton Standard has delivered a 3000 PSI SPE Propulsion Electrolyzer Stack and Special Test Fixture to the NASA Lyndon B. Johnson Space Center (JSC) Integrated Propulsion Test Article (IPTA) program in June 1990, per contract NAS9-18030. This prototype unit demonstrates the feasibility of SPE-high pressure water electrolysis for future space applications such as Space Station propulsion and Lunar/Mars energy storage. The SPE-Propulsion Electrolyzer has met or exceeded all IPTA program goals. It continues to function as the primary hydrogen and oxygen source for the IPTA test bed at the NASA/JSC Propulsion and Power Division Thermochemical Test Branch.

  7. SPE propulsion electrolyzer for NASA's integrated propulsion test article

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Hamilton Standard has delivered a 3000 PSI SPE Propulsion Electrolyzer Stack and Special Test Fixture to the NASA Lyndon B. Johnson Space Center (JSC) Integrated Propulsion Test Article (IPTA) program in June 1990, per contract NAS9-18030. This prototype unit demonstrates the feasibility of SPE-high pressure water electrolysis for future space applications such as Space Station propulsion and Lunar/Mars energy storage. The SPE-Propulsion Electrolyzer has met or exceeded all IPTA program goals. It continues to function as the primary hydrogen and oxygen source for the IPTA test bed at the NASA/JSC Propulsion and Power Division Thermochemical Test Branch.

  8. Air-breathing hypersonic vehicle guidance and control studies: An integrated trajectory/control analysis methodology, phase 2

    NASA Technical Reports Server (NTRS)

    Hattis, Philip D.; Malchow, Harvey L.

    1992-01-01

    An integrated trajectory/control analysis algorithm has been used to generate trajectories and desired control strategies for two different hypersonic air-breathing vehicle models and orbit targets. Both models used cubic spline curve fit tabulated winged-cone accelerator vehicle representations. Near-fuel-optimal, horizontal takeoff trajectories, imposing a dynamic pressure limit of 1000 psf, were developed. The first model analysis case involved a polar orbit and included the dynamic effects of using elevons to maintain longitudinal trim. Analysis results indicated problems with the adequacy of the propulsion model and highlighted dynamic pressure/altitude instabilities when using vehicle angle of attack as a control variable. Also, the magnitude of computed elevon deflections to maintain trim suggested a need for alternative pitch moment management strategies. The second analysis case was reformulated to use vehicle pitch attitude relative to the local vertical as the control variable. A new, more realistic, air-breathing propulsion model was incorporated. Pitch trim calculations were dropped and an equatorial orbit was specified. Changes in flight characteristics due to the new propulsion model have been identified. Flight regimes demanding rapid attitude changes have been noted. Also, some issues that would affect design of closed-loop controllers were ascertained.

  9. High-speed flight propulsion systems. Progress in Astronautics and Aeronautics. Vol. 137

    SciTech Connect

    Murthy, S.N.B.; Curran, E.T. USAF, Wright Laboratory, Wright-Patterson AFB, OH )

    1991-01-01

    Various papers on high-speed flight propulsion systems are presented. The topics addressed are: propulsion systems from takeoff to high-speed flight, propulsion system performance and integration for high Mach air-breathing flight, energy analysis of high-speed flight systems, waves and thermodynamics in high Mach number propulsive ducts, turbulent free shear layer mixing and combustion, turbulent mixing in supersonic combustion systems, mixing and mixing enhancement in supersonic reacting flowfields, study of combustion and heat-exchange processes in high-enthalpy short-duration facilities, and facility requirements for hypersonic propulsion system testing.

  10. Airbreathing Hypersonic Technology Vision Vehicles and Development Dreams

    NASA Technical Reports Server (NTRS)

    McClinton, C. R.; Hunt, J. L.; Ricketts, R. H.; Reukauf, P.; Peddie, C. L.

    1999-01-01

    Significant advancements in hypersonic airbreathing vehicle technology have been made in the country's research centers and industry over the past 40 years. Some of that technology is being validated with the X-43 flight tests. This paper presents an overview of hypersonic airbreathing technology status within the US, and a hypersonic technology development plan. This plan builds on the nation's large investment in hypersonics. This affordable, incremental plan focuses technology development on hypersonic systems, which could be operating by the 2020's.

  11. Hypersonic airbreathing vehicle conceptual design (focus on aero-space plane)

    NASA Technical Reports Server (NTRS)

    Hunt, James L.; Martin, John G.

    1989-01-01

    The airbreathing single stage to orbit (SSTO) vehicle design environment is variable-rich, intricately networked and sensitivity intensive. As such, it represents a tremondous technology challenge. Creating a viable design will require sophisticated configuration/synthesis and the synergistic integration of advanced technologies across the discipline spectrum. In design exercises, reductions in the fuel weight-fraction requirements projected for an orbital vehicle concept can result from improvements in aerodynamics/controls, propulsion efficiencies and trajectory optimization; also, gains in the fuel weight-fraction achievable for such a concept can result from improvements in structural design, heat management techniques, and material properties. As these technology advances take place, closure on a viable vehicle design will be realizable.

  12. Geometry Modeling and Adaptive Control of Air-Breathing Hypersonic Vehicles

    NASA Astrophysics Data System (ADS)

    Vick, Tyler Joseph

    Air-breathing hypersonic vehicles have the potential to provide global reach and affordable access to space. Recent technological advancements have made scramjet-powered flight achievable, as evidenced by the successes of the X-43A and X-51A flight test programs over the last decade. Air-breathing hypersonic vehicles present unique modeling and control challenges in large part due to the fact that scramjet propulsion systems are highly integrated into the airframe, resulting in strongly coupled and often unstable dynamics. Additionally, the extreme flight conditions and inability to test fully integrated vehicle systems larger than X-51 before flight leads to inherent uncertainty in hypersonic flight. This thesis presents a means to design vehicle geometries, simulate vehicle dynamics, and develop and analyze control systems for hypersonic vehicles. First, a software tool for generating three-dimensional watertight vehicle surface meshes from simple design parameters is developed. These surface meshes are compatible with existing vehicle analysis tools, with which databases of aerodynamic and propulsive forces and moments can be constructed. A six-degree-of-freedom nonlinear dynamics simulation model which incorporates this data is presented. Inner-loop longitudinal and lateral control systems are designed and analyzed utilizing the simulation model. The first is an output feedback proportional-integral linear controller designed using linear quadratic regulator techniques. The second is a model reference adaptive controller (MRAC) which augments this baseline linear controller with an adaptive element. The performance and robustness of each controller are analyzed through simulated time responses to angle-of-attack and bank angle commands, while various uncertainties are introduced. The MRAC architecture enables the controller to adapt in a nonlinear fashion to deviations from the desired response, allowing for improved tracking performance, stability, and

  13. NASA's Launch Propulsion Systems Technology Roadmap

    NASA Technical Reports Server (NTRS)

    McConnaughey, Paul K.; Femminineo, Mark G.; Koelfgen, Syri J.; Lepsch, Roger A; Ryan, Richard M.; Taylor, Steven A.

    2012-01-01

    Safe, reliable, and affordable access to low-Earth (LEO) orbit is necessary for all of the United States (US) space endeavors. In 2010, NASA s Office of the Chief Technologist commissioned 14 teams to develop technology roadmaps that could be used to guide the Agency s and US technology investment decisions for the next few decades. The Launch Propulsion Systems Technology Area (LPSTA) team was tasked to address the propulsion technology challenges for access to LEO. The developed LPSTA roadmap addresses technologies that enhance existing solid or liquid propulsion technologies and their related ancillary systems or significantly advance the technology readiness level (TRL) of less mature systems like airbreathing, unconventional, and other launch technologies. In developing this roadmap, the LPSTA team consulted previous NASA, military, and industry studies as well as subject matter experts to develop their assessment of this field, which has fundamental technological and strategic impacts for US space capabilities.

  14. JANNAF 35th Combustion Subcommittee and 17th Propulsion Systems Hazards Subcommittee Meeting: Joint Sessions

    NASA Technical Reports Server (NTRS)

    Fry, Ronald S. (Editor); Gannaway, Mary T. (Editor); Rognan, Melanie (Editor)

    1998-01-01

    This publication is a compilation of 15 unclassified/unlimited technical papers presented at the 1998 meeting of the Joint Army-Navy-NASA-Air Force (JANNAF) Combustion Subcommittee (CS) and Propulsion Systems Hazards Subcommittee (PSHS) held jointly with the Airbreathing Propulsion Subcommittee (APS). The meeting was held on 7 - 11 December 1 998 at Raytheon Systems Company and the Marriott Hotel, Tucson, AZ. Topics covered include advanced ingredients and reaction kinetics in solid propellants and experimental diagnostic techniques.

  15. Rocket Based Combined Cycle (RBCC) Propulsion Workshop, volume 2

    NASA Technical Reports Server (NTRS)

    Chojnacki, Kent T.

    1992-01-01

    The goal of the Rocket Based Combined Cycle (RBCC) Propulsion Technology Workshop, was to impart technology information to the propulsion community with respect to hypersonic combined cycle propulsion capabilities. The major recommendation resulting from this technology workshop was as follows: conduct a systems-level applications study to define the desired propulsion system and vehicle technology requirements for LEO launch vehicles. All SSTO and TSTO options using the various propulsion systems (airbreathing combined cycle, rocket-based combined cycle, and all rocket) must be considered. Such a study should be accomplished as soon as possible. It must be conducted with a consistent set of ground rules and assumptions. Additionally, the study should be conducted before any major expenditures on a RBCC technology development program occur.

  16. Aerothermodynamics of gas turbine and rocket propulsion

    NASA Astrophysics Data System (ADS)

    Oates, G. C.

    The present book is intended to serve as a text for both graduate and under-graduate courses in aerospace propulsion. After introducing fundamental concepts of thermodynamics and quasi-one-dimensional flows, these are applied to rocket nozzle behavior prediction. Airbreathing engines are considered within the framework of ideal cycle analysis at first, and then real engine effects are introduced through definition of component measures. Selected examples of nonideal cycles are considered in detail, design concepts are extended to off-design estimation, and the restrictive effects of fixed geometry engines are revealed. Attention is also given to the elementary aerodynamics of turbomachinery.

  17. Computational analysis of hypersonic airbreathing aircraft flow fields

    NASA Technical Reports Server (NTRS)

    Dwoyer, Douglas L.; Kumar, Ajay

    1987-01-01

    The general problem of calculating the flow fields associated with hypersonic airbreathing aircraft is presented. Unique aspects of hypersonic aircraft aerodynamics are introduced and their demands on computational fluid dynamics are outlined. Example calculations associated with inlet/forebody integration and hypersonic nozzle design are presented to illustrate the nature of the problems considered.

  18. A Review of Laser Ablation Propulsion

    SciTech Connect

    Phipps, Claude; Bohn, Willy; Lippert, Thomas; Sasoh, Akihiro; Schall, Wolfgang; Sinko, John

    2010-10-08

    Laser Ablation Propulsion is a broad field with a wide range of applications. We review the 30-year history of laser ablation propulsion from the transition from earlier pure photon propulsion concepts of Oberth and Saenger through Kantrowitz's original laser ablation propulsion idea to the development of air-breathing 'Lightcraft' and advanced spacecraft propulsion engines. The polymers POM and GAP have played an important role in experiments and liquid ablation fuels show great promise. Some applications use a laser system which is distant from the propelled object, for example, on another spacecraft, the Earth or a planet. Others use a laser that is part of the spacecraft propulsion system on the spacecraft. Propulsion is produced when an intense laser beam strikes a condensed matter surface and produces a vapor or plasma jet. The advantages of this idea are that exhaust velocity of the propulsion engine covers a broader range than is available from chemistry, that it can be varied to meet the instantaneous demands of the particular mission, and that practical realizations give lower mass and greater simplicity for a payload delivery system. We review the underlying theory, buttressed by extensive experimental data. The primary problem in laser space propulsion theory has been the absence of a way to predict thrust and specific impulse over the transition from the vapor to the plasma regimes. We briefly discuss a method for combining two new vapor regime treatments with plasma regime theory, giving a smooth transition from one regime to the other. We conclude with a section on future directions.

  19. A Comparison of Propulsion Concepts for SSTO Reusable Launchers

    NASA Astrophysics Data System (ADS)

    Varvill, R.; Bond, A.

    This paper discusses the relevant selection criteria for a single stage to orbit (SSTO) propulsion system and then reviews the characteristics of the typical engine types proposed for this role against these criteria. The engine types considered include Hydrogen/Oxygen (H2/O2) rockets, Scramjets, Turbojets, Turborockets and Liquid Air Cycle Engines. In the authors opinion none of the above engines are able to meet all the necessary criteria for an SSTO propulsion system simultaneously. However by selecting appropriate features from each it is possible to synthesise a new class of engines which are specifically optimised for the SSTO role. The resulting engines employ precooling of the airstream and a high internal pressure ratio to enable a relatively conventional high pressure rocket combustion chamber to be utilised in both airbreathing and rocket modes. This results in a significant mass saving with installation advantages which by careful design of the cycle thermodynamics enables the full potential of airbreathing to be realised. The SABRE engine which powers the SKYLON launch vehicle is an example of one of these so called `Precooled hybrid airbreathing rocket engines' and the concep- tual reasoning which leads to its main design parameters are described in the paper.

  20. Transcriptomic Analysis of Compromise Between Air-Breathing and Nutrient Uptake of Posterior Intestine in Loach (Misgurnus anguillicaudatus), an Air-Breathing Fish.

    PubMed

    Huang, Songqian; Cao, Xiaojuan; Tian, Xianchang

    2016-08-01

    Dojo loach (Misgurnus anguillicaudatus) is an air-breathing fish species by using its posterior intestine to breathe on water surface. So far, the molecular mechanism about accessory air-breathing in fish is seldom addressed. Five cDNA libraries were constructed here for loach posterior intestines form T01 (the initial stage group), T02 (mid-stage of normal group), T03 (end stage of normal group), T04 (mid-stage of air-breathing inhibited group), and T05 (the end stage of air-breathing inhibited group) and subjected to perform RNA-seq to compare their transcriptomic profilings. A total of 92,962 unigenes were assembled, while 37,905 (40.77 %) unigenes were successfully annotated. 2298, 1091, and 3275 differentially expressed genes (fn1, ACE, EGFR, Pxdn, SDF, HIF, VEGF, SLC2A1, SLC5A8 etc.) were observed in T04/T02, T05/T03, and T05/T04, respectively. Expression levels of many genes associated with air-breathing and nutrient uptake varied significantly between normal and intestinal air-breathing inhibited group. Intraepithelial capillaries in posterior intestines of loaches from T05 were broken, while red blood cells were enriched at the surface of intestinal epithelial lining with 241 ± 39 cells per millimeter. There were periodic acid-schiff (PAS)-positive epithelial mucous cells in posterior intestines from both normal and air-breathing inhibited groups. Results obtained here suggested an overlap of air-breathing and nutrient uptake function of posterior intestine in loach. Intestinal air-breathing inhibition in loach would influence the posterior intestine's nutrient uptake ability and endothelial capillary structure stability. This study will contribute to our understanding on the molecular regulatory mechanisms of intestinal air-breathing in loach. PMID:27457889

  1. Airbreathing Hypersonic Systems Focus at NASA Langley Research Center

    NASA Technical Reports Server (NTRS)

    Hunt, James L.; Rausch, Vincent L.

    1998-01-01

    This paper presents the status of the airbreathing hypersonic airplane and space-access vehicle design matrix, reflects on the synergies and issues, and indicates the thrust of the effort to resolve the design matrix and to focus/advance systems technology maturation. Priority is given to the design of the vision operational vehicles followed by flow-down requirements to flight demonstrator vehicles and their design for eventual consideration in the Future-X Program.

  2. 2-D Air-Breathing Lightcraft Engine Experiments in Hypersonic Conditions

    NASA Astrophysics Data System (ADS)

    Salvador, Israel I.; Myrabo, Leik N.; Minucci, Marco A. S.; de Oliveira, Antonio C.; Toro, Paulo G. P.; Chanes, José B.; Rego, Israel S.

    2011-11-01

    Experiments were performed with a 2-D, repetitively-pulsed (RP) laser Lightcraft model in hypersonic flow conditions. The main objective was the feasibility analysis for impulse generation with repetitively-pulsed air-breathing laser Lightcraft engines at hypersonic speeds. The future application of interest for this basic research endeavor is the laser launch of pico-, nano-, and micro-satellites (i.e., 0.1-100 kg payloads) into Low-Earth-Orbit, at low-cost and on-demand. The laser propulsion experiments employed a Hypersonic Shock Tunnel integrated with twin gigawatt pulsed Lumonics 620-TEA CO2 lasers (˜ 1 μs pulses), to produce the required test conditions. This hypersonic campaign was carried out at nominal Mach numbers ranging from 6 to 10. Time-dependent surface pressure distributions were recorded together with Schlieren movies of the flow field structure resulting from laser energy deposition. Results indicated laser-induced pressure increases of 0.7-0.9 bar with laser pulse energies of ˜ 170 J, on off-shroud induced breakdown condition, and Mach number of 7.

  3. Biannular Airbreathing Nozzle Rig (BANR) facility checkout and plug nozzle performance test data

    NASA Astrophysics Data System (ADS)

    Cummings, Chase B.

    2010-09-01

    The motivation for development of a supersonic business jet (SSBJ) platform lies in its ability to create a paradigm shift in the speed and reach of commercial, private, and government travel. A full understanding of the performance capabilities of exhaust nozzle configurations intended for use in potential SSBJ propulsion systems is critical to the design of an aircraft of this type. Purdue University's newly operational Biannular Airbreathing Nozzle Rig (BANR) is a highly capable facility devoted to the testing of subscale nozzles of this type. The high accuracy, six-axis force measurement system and complementary mass flowrate measurement capabilities of the BANR facility make it rather ideally suited for exhaust nozzle performance appraisal. Detailed accounts pertaining to methods utilized in the proper checkout of these diagnostic capabilities are contained herein. Efforts to quantify uncertainties associated with critical BANR test measurements are recounted, as well. Results of a second hot-fire test campaign of a subscale Gulfstream Aerospace Corporation (GAC) axisymmetric, shrouded plug nozzle are presented. Determined test article performance parameters (nozzle thrust efficiencies and discharge coefficients) are compared to those of a previous test campaign and numerical simulations of the experimental set-up. Recently acquired data is compared to published findings pertaining to plug nozzle experiments of similar scale and operating range. Suggestions relating to the future advancement and improvement of the BANR facility are provided. Lessons learned with regards to test operations and calibration procedures are divulged in an attempt to aid future facility users, as well.

  4. The Sensitivity of Precooled Air-Breathing Engine Performance to Heat Exchanger Design Parameters

    NASA Astrophysics Data System (ADS)

    Webber, H.; Bond, A.; Hempsell, M.

    The issues relevant to propulsion design for Single Stage To Orbit (SSTO) vehicles are considered. In particular two air- breathing engine concepts involving precooling are compared; SABRE (Synergetic Air-Breathing and Rocket Engine) as designed for the Skylon SSTO launch vehicle, and a LACE (Liquid Air Cycle Engine) considered in the 1960's by the Americans for an early generation spaceplane. It is shown that through entropy minimisation the SABRE has made substantial gains in performance over the traditional LACE precooled engine concept, and has shown itself as the basis of a viable means of realising a SSTO vehicle. Further, it is demonstrated that the precooler is a major source of thermodynamic irreversibility within the engine cycle and that further reduction in entropy can be realised by increasing the heat transfer coefficient on the air side of the precooler. If this were to be achieved, it would improve the payload mass delivered to orbit by the Skylon launch vehicle by between 5 and 10%.

  5. Analysis of Laser-Generated Impulse In An Airbreathing Pulsed Detonation Engine: Part 1

    NASA Astrophysics Data System (ADS)

    Richard, Jacques C.; Myrabo, Leik N.

    2005-04-01

    An investigation is performed on an airbreathing laser propulsion (LP) system designed to propel a 1.4 m diameter, 120-kg (dry mass) vehicle called the Lightcraft Technology Demonstrator (LTD) into low Earth orbit, along with its opto-electronics payload. The LTD concept led directly to the model ♯200 lightcraft — recently demonstrated in laboratory and flight experiments at White Sands Missile Range, NM at the High Energy Laser Systems Test Facility (HELSTF), using the 10-kW PLVTS CO2 laser. The pulsed detonation wave engine (PDE) employs repetitively ignited, laser-supported detonation (LSD) waves to develop thrust by expanding high pressure blast waves over an annular, interior shroud surface. Numerical simulation of thruster impulse is accomplished with a 1-D cylindrical model of blast waves propagating radially outward from a laser-generated `line-source' of high temperature, high pressure air. External airflow over the LTD structure is also analyzed to predict basic engine/vehicle drag characteristics, including inlet total pressure recovery, and captured air mass flow rate — all projected vs. flight Mach number and altitude.

  6. Investigation of air-breathing, hypersonic missile configurations within external box constraints

    NASA Astrophysics Data System (ADS)

    Starkey, Ryan Peter

    2000-12-01

    Aspects relating to the aerodynamic, geometric, and propulsive design and analysis of missile-class, waverider-based hypersonic vehicles are explored. A quasi-one-dimensional engine model, including the effects of fuel injection, mixing, chemical production rates, heat transfer, and viscous losses is developed and utilized to assess the effects of finite rate hydrocarbon chemistry on optimized missile configurations. Resultant optimized single and double engine missile designs are shown for changes in fuel mixing length, fuel mixing efficiency, fuel injector location, and assumed fuel mass fraction. The effects of these different design conditions on the cruise range are explored, as well as perturbations around these design points for optimized vehicles. Aerodynamics are evaluated using a newly developed modified shock-expansion method. Missiles are optimized for steady-state trim conditions at the beginning of cruise using parallelized genetic algorithm optimization software developed for this study. All missile designs are assumed to reach cruising altitude and velocity through the use of an external rocket booster. The missile is geometrically constrained to fit within the 0.61 m x 0.61 m x 4.27 m [2 foot x 2 foot x 14 foot] box limits for a Naval vertical launch tube and has a desired cruise range of 750 km [400 nm] at Mach 6. Investigations are also shown for the effects of various modeling assumptions: (1) shock-expansion method versus a new modified shock-expansion aerodynamic method, (2) boundary layer assumptions, (3) assumed combustor temperature profile versus finite rate chemistry computations, and (4) ratio of specific heats assumptions. An overall analysis and optimization toolkit is developed for quick calculation of hypersonic aerodynamics and propulsion with added insight into externally constrained vehicles. Results show that the optimized combustor designs were extremely sensitive to small changes in flow conditions and that high

  7. JANNAF 17th Propulsion Systems Hazards Subcommittee Meeting. Volume 1

    NASA Technical Reports Server (NTRS)

    Cocchiaro, James E. (Editor); Gannaway, Mary T. (Editor); Rognan, Melanie (Editor)

    1998-01-01

    Volume 1, the first of two volumes is a compilation of 16 unclassified/unlimited technical papers presented at the 17th meeting of the Joint Army-Navy-NASA-Air Force (JANNAF) Propulsion Systems Hazards Subcommittee (PSHS) held jointly with the 35th Combustion Subcommittee (CS) and Airbreathing Propulsion Subcommittee (APS). The meeting was held on 7 - 11 December 1998 at Raytheon Systems Company and the Marriott Hotel, Tucson, AZ. Topics covered include projectile and shaped charge jet impact vulnerability of munitions; thermal decomposition and cookoff behavior of energetic materials; damage and hot spot initiation mechanisms with energetic materials; detonation phenomena of solid energetic materials; and hazard classification, insensitive munitions, and propulsion systems safety.

  8. JANNAF 19th Propulsion Systems Hazards Subcommittee Meeting. Volume 1

    NASA Technical Reports Server (NTRS)

    Cocchiaro, James E. (Editor); Kuckels, Melanie C. (Editor)

    2000-01-01

    This volume, the first of two volumes is a compilation of 25 unclassified/unlimited-distribution technical papers presented at the Joint Army-Navy-NASA-Air Force (JANNAF) 19th Propulsion Systems Hazards Subcommittee (PSHS) meeting held jointly with the 37th Combustion Subcommittee (CS) and 25th Airbreathing Propulsion Subcommittee (APS), and 1st Modeling and Simulation Subcommittee (MSS) meetings. The meeting was held 13-17 November 2000 at the Naval Postgraduate School and Hyatt Regency Hotel, Monterey, California. Topics covered at the PSHS meeting include: impact and thermal vulnerability of gun propellants; thermal decomposition and cookoff behavior of energetic materials; violent reaction and detonation phenomena of solid energetic materials subjected to shock and impact loading; and hazard classification, and insensitive munitions testing of propellants and propulsion systems.

  9. JANNAF 18th Propulsion Systems Hazards Subcommittee Meeting. Volume 1

    NASA Technical Reports Server (NTRS)

    Cocchiaro, James E. (Editor); Gannaway, Mary T. (Editor)

    1999-01-01

    This volume, the first of two volumes is a compilation of 18 unclassified/unlimited-distribution technical papers presented at the Joint Army-Navy-NASA-Air Force (JANNAF) 18th Propulsion Systems Hazards Subcommittee (PSHS) meeting held jointly with the 36th Combustion Subcommittee (CS) and 24th Airbreathing Propulsion Subcommittee (APS) meetings. The meeting was held 18-21 October 1999 at NASA Kennedy Space Center and The DoubleTree Oceanfront Hotel, Cocoa Beach, Florida. Topics covered at the PSHS meeting include: shaped charge jet and kinetic energy penetrator impact vulnerability of gun propellants; thermal decomposition and cookoff behavior of energetic materials; violent reaction; detonation phenomena of solid energetic materials subjected to shock and impact stimuli; and hazard classification, insensitive munitions, and propulsion systems safety.

  10. Structural Mechanics and Dynamics Branch

    NASA Technical Reports Server (NTRS)

    Stefko, George

    2003-01-01

    The 2002 annual report of the Structural Mechanics and Dynamics Branch reflects the majority of the work performed by the branch staff during the 2002 calendar year. Its purpose is to give a brief review of the branch s technical accomplishments. The Structural Mechanics and Dynamics Branch develops innovative computational tools, benchmark experimental data, and solutions to long-term barrier problems in the areas of propulsion aeroelasticity, active and passive damping, engine vibration control, rotor dynamics, magnetic suspension, structural mechanics, probabilistics, smart structures, engine system dynamics, and engine containment. Furthermore, the branch is developing a compact, nonpolluting, bearingless electric machine with electric power supplied by fuel cells for future "more electric" aircraft. An ultra-high-power-density machine that can generate projected power densities of 50 hp/lb or more, in comparison to conventional electric machines, which generate usually 0.2 hp/lb, is under development for application to electric drives for propulsive fans or propellers. In the future, propulsion and power systems will need to be lighter, to operate at higher temperatures, and to be more reliable in order to achieve higher performance and economic viability. The Structural Mechanics and Dynamics Branch is working to achieve these complex, challenging goals.

  11. Focused technology: Nuclear propulsion

    NASA Technical Reports Server (NTRS)

    Miller, Thomas J.

    1993-01-01

    Five viewgraphs are presented that outline the objectives and elements of the Nuclear Propulsion Program, mission considerations, propulsion technologies, and the logic flow path for nuclear propulsion development.

  12. Prospective new transportation application initiatives in NASA's earth-to-orbit propulsion technology program

    NASA Technical Reports Server (NTRS)

    Escher, William J. D.

    1992-01-01

    NASA's Earth-to-Orbit (ETO) Propulsion Technology Program, a multi-year/multi-task focused technology effort is, today, highly focused on conventional high-thrust cryogenic liquid chemical rocket engines and their envisioned future technology needs. But as highlighted in the U.S. National Ten-Year Space Launch Technology Plan, a set of less-conventional propulsion subjects, ones which offer significant promise for both, improving the state of the art and opening up new propulsion-capability possibilities, is now directed to the space propulsion planning community's attention. In conducting its forward-planning activities, it is highly appropriate that the ETO Program (and other programs as well) carefully consider integrating these "new initiative" subjects into the taskwork of future years. After an introductory consideration of the National Plan's propulsion-related directives, followed by a brief background overview of the ETO Program, the following specific new-initiative candidates are discussed from the standpoint of technology-program planning: operationally efficient propulsion systems; high-thrust hybrid rocket propulsion; low-cost, low-pressure expendable propulsion subsystems; advanced cryogenic in-space propulsion systems; integrated modular engine (IME) configured propulsion systems, and combined-cycle airbreathing/rocket propulsion systems.

  13. Replacement of chemical rocket launchers by beamed energy propulsion.

    PubMed

    Fukunari, Masafumi; Arnault, Anthony; Yamaguchi, Toshikazu; Komurasaki, Kimiya

    2014-11-01

    Microwave Rocket is a beamed energy propulsion system that is expected to reach space at drastically lower cost. This cost reduction is estimated by replacing the first-stage engine and solid rocket boosters of the Japanese H-IIB rocket with Microwave Rocket, using a recently developed thrust model in which thrust is generated through repetitively pulsed microwave detonation with a reed-valve air-breathing system. Results show that Microwave Rocket trajectory, in terms of velocity versus altitude, can be designed similarly to the current H-IIB first stage trajectory. Moreover, the payload ratio can be increased by 450%, resulting in launch-cost reduction of 74%. PMID:25402933

  14. Heat transfer in space power and propulsion systems

    NASA Technical Reports Server (NTRS)

    Hendricks, R. C.; Simoneau, R. J.; Dunning, J. W., Jr.

    1986-01-01

    NASA's planned Space Station has projected power requirements in the 75-300 kW range; attention is presently given to the range of power system configurations thus far proposed. These are a silicon solar cell system incorporating regenerative fuel cell or battery storage, with a 10-year lifetime, a solar-dynamic power system with phase-change or regenerative fuel cell energy storage, and a combination of these two alternatives. A development status evaluation is also given for the propulsion systems that may be used by next-generation boosters. These include such novel airbreathing systems as turboramjets, air liquefaction cycle rockets, airturboramjet/rockets, and supersonic combustion ramjets.

  15. Electromagnetic Propulsion

    NASA Technical Reports Server (NTRS)

    Schafer, Charles

    2000-01-01

    The design and development of an Electromagnetic Propulsion is discussed. Specific Electromagnetic Propulsion Topics discussed include: (1) Technology for Pulse Inductive Thruster (PIT), to design, develop, and test of a multirepetition rate pulsed inductive thruster, Solid-State Switch Technology, and Pulse Driver Network and Architecture; (2) Flight Weight Magnet Survey, to determine/develop light weight high performance magnetic materials for potential application Advanced Space Flight Systems as these systems develop; and (3) Magnetic Flux Compression, to enable rapid/robust/reliable omni-planetary space transportation within realistic development and operational costs constraints.

  16. Air-breathing hypersonic vehicle guidance and control studies; An integrated trajectory/control analysis methodology: Phase 1

    NASA Technical Reports Server (NTRS)

    Hattis, Philip D.; Malchow, Harvey L.

    1991-01-01

    A tool which generates optimal trajectory/control histories in an integrated manner is generically adapted to the treatment of single-stage-to-orbit air-breathing hypersonic vehicles. The methodology is implemented as a two point boundary value problem solution technique. Its use permits an assessment of an entire near-minimum-fuel trajectory and desired control strategy from takeoff to orbit while satisfying physically derived inequality constraints and while achieving efficient propulsive mode phasing. A simpler analysis strategy that partitions the trajectory into several boundary condition matched segments is also included to construct preliminary trajectory and control history representations with less computational burden than is required for the overall flight profile assessment. A demonstration was accomplished using a tabulated example (winged-cone accelerator) vehicle model that is combined with a newly developed multidimensional cubic spline data smoothing routine. A constrained near-fuel-optimal trajectory, imposing a dynamic pressure limit of 1000 psf, was developed from horizontal takeoff to 20,000 ft/sec relative air speed while aiming for a polar orbit. Previously unspecified propulsive discontinuities were located. Flight regimes demanding rapid attitude changes were identified, dictating control effector and closed-loop controller authority was ascertained after evaluating effector use for vehicle trim. Also, inadequacies in vehicle model representations and specific subsystem models with insufficient fidelity were determined based on unusual control characteristics and/or excessive sensitivity to uncertainty.

  17. Role of Air-Breathing Pulse Detonation Engines in High Speed Propulsion

    NASA Technical Reports Server (NTRS)

    Povinelli, Louis A.; Lee, Jin-Ho; Anderberg, Michael O.

    2001-01-01

    In this paper, the effect of flight Mach number on the relative performance of pulse detonation engines and gas turbine engines is investigated. The effect of ram and mechanical compression on combustion inlet temperature and the subsequent sensible heat release is determined. Comparison of specific thrust, fuel consumption and impulse for the two engines show the relative benefits over the Mach number range.

  18. Filtered Mass Density Function for Design Simulation of High Speed Airbreathing Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Drozda, T. G.; Sheikhi, R. M.; Givi, Peyman

    2001-01-01

    The objective of this research is to develop and implement new methodology for large eddy simulation of (LES) of high-speed reacting turbulent flows. We have just completed two (2) years of Phase I of this research. This annual report provides a brief and up-to-date summary of our activities during the period: September 1, 2000 through August 31, 2001. In the work within the past year, a methodology termed "velocity-scalar filtered density function" (VSFDF) is developed and implemented for large eddy simulation (LES) of turbulent flows. In this methodology the effects of the unresolved subgrid scales (SGS) are taken into account by considering the joint probability density function (PDF) of all of the components of the velocity and scalar vectors. An exact transport equation is derived for the VSFDF in which the effects of the unresolved SGS convection, SGS velocity-scalar source, and SGS scalar-scalar source terms appear in closed form. The remaining unclosed terms in this equation are modeled. A system of stochastic differential equations (SDEs) which yields statistically equivalent results to the modeled VSFDF transport equation is constructed. These SDEs are solved numerically by a Lagrangian Monte Carlo procedure. The consistency of the proposed SDEs and the convergence of the Monte Carlo solution are assessed by comparison with results obtained by an Eulerian LES procedure in which the corresponding transport equations for the first two SGS moments are solved. The unclosed SGS convection, SGS velocity-scalar source, and SGS scalar-scalar source in the Eulerian LES are replaced by corresponding terms from VSFDF equation. The consistency of the results is then analyzed for a case of two dimensional mixing layer.

  19. Sensor/actuator failure detection and isolation for airbreathing propulsion systems

    NASA Technical Reports Server (NTRS)

    Leininger, G. G.; Behbehani, K.

    1980-01-01

    In this paper, the Generalized Likelihood Ratio (GLR) test is used to detect and isolate sensor and/or actuator failures when a digital computer simulation model of the physical system is available. The input to the GLR detector is an innovation sequence formed by subtracting the model outputs from the sensed outputs. Application of the GLR detector to the General Electric QCSEE turbofan engine demonstrates the utility of the proposed procedure.

  20. Study of Unsteady, Sphere-Driven, Shock-Induced Combustion for Application to Hypervelocity Airbreathing Propulsion

    NASA Technical Reports Server (NTRS)

    Axdahl, Erik; Kumar, Ajay; Wilhite, Alan

    2011-01-01

    A premixed, shock-induced combustion engine has been proposed in the past as a viable option for operating in the Mach 10 to 15 range in a single stage to orbit vehicle. In this approach, a shock is used to initiate combustion in a premixed fuel/air mixture. Apparent advantages over a conventional scramjet engine include a shorter combustor that, in turn, results in reduced weight and heating loads. There are a number of technical challenges that must be understood and resolved for a practical system: premixing of fuel and air upstream of the combustor without premature combustion, understanding and control of instabilities of the shock-induced combustion front, ability to produce sufficient thrust, and the ability to operate over a range of Mach numbers. This study evaluated the stability of the shock-induced combustion front in a model problem of a sphere traveling in a fuel/air mixture at high Mach numbers. A new, rapid analysis method was developed and applied to study such flows. In this method the axisymmetric, body-centric Navier-Stokes equations were expanded about the stagnation streamline of a sphere using the local similarity hypothesis in order to reduce the axisymmetric equations to a quasi-1D set of equations. These reduced sets of equations were solved in the stagnation region for a number of flow conditions in a premixed, hydrogen/air mixture. Predictions from the quasi-1D analysis showed very similar stable or unstable behavior of the shock-induced combustion front as compared to experimental studies and higher-fidelity computational results. This rapid analysis tool could be used in parametric studies to investigate effects of fuel rich/lean mixtures, non-uniformity in mixing, contaminants in the mixture, and different chemistry models.

  1. 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.

  2. 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.

  3. Advanced controls for airbreathing engines, volume 3: Allison gas turbine

    NASA Technical Reports Server (NTRS)

    Bough, R. M.

    1993-01-01

    The application of advanced control concepts to airbreathing engines may yield significant improvements in aircraft/engine performance and operability. Screening studies of advanced control concepts for airbreathing engines were conducted by three major domestic aircraft engine manufacturers to determine the potential impact of concepts 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 advanced control concepts was formulated and evaluated in a two-phase study to quantify each concept's impact on desired engine characteristics. To aid in the evaluation specific 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 are defined and described. The concept potential impact on engine performance was determined. Relevant figures of merit on which to evaluate the concepts are determined. Finally, the concepts are ranked with respect to the target aircraft/engine missions. A final report describing the screening studies was prepared by each engine manufacturer. Volume 3 of these reports describes the studies performed by the Allison Gas Turbine Division.

  4. Shoot branching.

    PubMed

    Ward, Sally P; Leyser, Ottoline

    2004-02-01

    The mature form of a plant shoot system is an expression of several genetically controlled traits, many of which are also environmentally regulated. A major component of this architectural variation is the degree of shoot branching. Recent results indicate conserved mechanisms for shoot branch development across the monocots and eudicots. The existence of a novel long-range branch-inhibiting signal has been inferred from studies of branching mutants in pea and Arabidopsis. PMID:14732444

  5. Technology Roadmap for Dual-Mode Scramjet Propulsion to Support Space-Access Vision Vehicle Development

    NASA Technical Reports Server (NTRS)

    Cockrell, Charles E., Jr.; Auslender, Aaron H.; Guy, R. Wayne; McClinton, Charles R.; Welch, Sharon S.

    2002-01-01

    Third-generation reusable launch vehicle (RLV) systems are envisioned that utilize airbreathing and combined-cycle propulsion to take advantage of potential performance benefits over conventional rocket propulsion and address goals of reducing the cost and enhancing the safety of systems to reach earth orbit. The dual-mode scramjet (DMSJ) forms the core of combined-cycle or combination-cycle propulsion systems for single-stage-to-orbit (SSTO) vehicles and provides most of the orbital ascent energy. These concepts are also relevant to two-stage-to-orbit (TSTO) systems with an airbreathing first or second stage. Foundation technology investments in scramjet propulsion are driven by the goal to develop efficient Mach 3-15 concepts with sufficient performance and operability to meet operational system goals. A brief historical review of NASA scramjet development is presented along with a summary of current technology efforts and a proposed roadmap. The technology addresses hydrogen-fueled combustor development, hypervelocity scramjets, multi-speed flowpath performance and operability, propulsion-airframe integration, and analysis and diagnostic tools.

  6. Mechanical Components Branch Test Facilities and Capabilities

    NASA Technical Reports Server (NTRS)

    Oswald, Fred B.

    2004-01-01

    The Mechanical Components Branch at NASA Glenn Research Center formulates, conducts, and manages research focused on propulsion systems for both present and advanced aeronautical and space vehicles. The branch is comprised of research teams that perform basic research in three areas: mechanical drives, aerospace seals, and space mechanisms. Each team has unique facilities for testing aerospace hardware and concepts. This report presents an overview of the Mechanical Components Branch test facilities.

  7. Propulsion controls

    NASA Technical Reports Server (NTRS)

    Harkney, R. D.

    1980-01-01

    Increased system requirements and functional integration with the aircraft have placed an increased demand on control system capability and reliability. To provide these at an affordable cost and weight and because of the rapid advances in electronic technology, hydromechanical systems are being phased out in favor of digital electronic systems. The transition is expected to be orderly from electronic trimming of hydromechanical controls to full authority digital electronic control. Future propulsion system controls will be highly reliable full authority digital electronic with selected component and circuit redundancy to provide the required safety and reliability. Redundancy may include a complete backup control of a different technology for single engine applications. The propulsion control will be required to communicate rapidly with the various flight and fire control avionics as part of an integrated control concept.

  8. Propulsion materials

    SciTech Connect

    Wall, Edward J.; Sullivan, Rogelio A.; Gibbs, Jerry L.

    2008-01-01

    The Department of Energy’s (DOE’s) Office of Vehicle Technologies (OVT) is pleased to introduce the FY 2007 Annual Progress Report for the Propulsion Materials Research and Development Program. Together with DOE national laboratories and in partnership with private industry and universities across the United States, the program continues to engage in research and development (R&D) that provides enabling materials technology for fuel-efficient and environmentally friendly commercial and passenger vehicles.

  9. Instrumentation requirements from the user's view. [For airbreathing hypersonic engines

    SciTech Connect

    Harsha, P.T.

    1988-01-01

    The use of combustor diagnostics is considered from the point of view of demonstration of performance of an airbreathing hypersonic engine. The basic need is seen to be that of providing the data necessary to verify performance predictions for the engine as installed in the airplane. This necessitates the use of a diagnostics capability that can provide the inputs required by the computational analyses that will be used to assess this performance. Because of the cost of ground test facilities, a premium is placed on measurement technique reliability and redundancy of instrumentation. A mix of nonintrusive optical techniques and probe-based measurements is seen to be the best approach using current diagnostics capability; one such instrument mix is outlined for a ramjet/scramjet test program. 11 references.

  10. Engines and innovation: Lewis Laboratory and American propulsion technology

    NASA Technical Reports Server (NTRS)

    Dawson, Virginia Parker

    1991-01-01

    This book is an institutional history of the NASA Lewis Research Center, located in Cleveland, Ohio, from 1940, when Congress authorized funding for a third laboratory for the National Advisory Committee for Aeronautics, through the 1980s. The history of the laboratory is discussed in relation to the development of American propulsion technology, with particular focus on the transition in the 1940s from the use of piston engines in airplanes to jet propulsion and that from air-breathing engines to rocket technology when the National Aeronautics and Space Administration was established in 1958. The personalities and research philosophies of the people who shaped the history of the laboratory are discussed, as is the relationship of Lewis Research Center to the Case Institute of Technology.

  11. Air-breathing fuel cell stacks for portable power applications

    SciTech Connect

    Wilson, M.S.; DeCaro, D.; Neutzler, J.K.; Zawodzinski, C.; Gottesfeld, S.

    1996-10-01

    Increasing attention is being directed towards polymer electrolyte fuel cells as battery replacements because of their potentially superior energy densities and the possibility of `mechanical` refueling. On the low end of the power requirement scale (ca. 10 W), fuel cells can compete with primary and secondary batteries only if the fuel cell systems are simple, inexpensive, and reliable. Considerations of cost and simplicity (and minimal parasitic power) discourage the use of conventional performance enhancing subsystems (e.g., humidification, cooling, or forced-reactant flow). We are developing a stack design that is inherently self-regulating to allow effective operation without the benefit of such auxiliary components. The air cathode does not use forced flow to replenish the depleted oxygen. Instead, the oxygen in the air must diffuse into the stack from the periphery of the unit cells. For this reason the stack is described as `air-breathing.` This configuration limits the ability of water to escape which prevents the polymer electrolyte membranes from drying out, even at relatively high continuous operation temperatures (+60 degrees C). This results in stacks with reliable and stable performance. This air-breathing configuration assumes a unique stack geometry that utilizes circular flow-field plates with an annular hydrogen feed manifold and the single tie-bolt extending up through the central axis of the stack. With this geometry, the hydrogen supply to the unit cells is radially outward, and the air supply is from the periphery inward. This configuration has several advantages. The entire periphery is free to air access and allows greater heat conduction to enhance cooling. Furthermore, all of the components in the stack (e.g., the flow-fields, seals and membrane/electrode assemblies), are radially symmetrical, so part fabrication is simple and the entire system is potentially low-cost. Lastly, this configuration is compact and lightweight.

  12. NASA's Advanced Propulsion Technology Activities for Third Generation Fully Reusable Launch Vehicle Applications

    NASA Technical Reports Server (NTRS)

    Hueter, Uwe

    2000-01-01

    NASA's Office of Aeronautics and Space Transportation Technology (OASTT) established the following three major goals, referred to as "The Three Pillars for Success": Global Civil Aviation, Revolutionary Technology Leaps, and Access to Space. The Advanced Space Transportation Program Office (ASTP) at the NASA's Marshall Space Flight Center in Huntsville, Ala. focuses on future space transportation technologies under the "Access to Space" pillar. The Propulsion Projects within ASTP under the investment area of Spaceliner100, focus on the earth-to-orbit (ETO) third generation reusable launch vehicle technologies. The goals of Spaceliner 100 is to reduce cost by a factor of 100 and improve safety by a factor of 10,000 over current conditions. The ETO Propulsion Projects in ASTP, are actively developing combination/combined-cycle propulsion technologies that utilized airbreathing propulsion during a major portion of the trajectory. System integration, components, materials and advanced rocket technologies are also being pursued. Over the last several years, one of the main thrusts has been to develop rocket-based combined cycle (RBCC) technologies. The focus has been on conducting ground tests of several engine designs to establish the RBCC flowpaths performance. Flowpath testing of three different RBCC engine designs is progressing. Additionally, vehicle system studies are being conducted to assess potential operational space access vehicles utilizing combined-cycle propulsion systems. The design, manufacturing, and ground testing of a scale flight-type engine are planned. The first flight demonstration of an airbreathing combined cycle propulsion system is envisioned around 2005. The paper will describe the advanced propulsion technologies that are being being developed under the ETO activities in the ASTP program. Progress, findings, and future activities for the propulsion technologies will be discussed.

  13. Highlights of NASA's Special ETO Program Planning Workshop on rocket-based combined-cycle propulsion system technologies

    NASA Technical Reports Server (NTRS)

    Escher, W. J. D.

    1992-01-01

    A NASA workshop on rocket-based combined-cycle propulsion technologies is described emphasizing the development of a starting point for earth-to-orbit (ETO) rocket technologies. The tutorial is designed with attention given to the combined development of aeronautical airbreathing propulsion and space rocket propulsion. The format, agenda, and group deliberations for the tutorial are described, and group deliberations include: (1) mission and space transportation infrastructure; (2) vehicle-integrated propulsion systems; (3) development operations, facilities, and human resource needs; and (4) spaceflight fleet applications and operations. Although incomplete the workshop elevates the subject of combined-cycle hypersonic propulsion and develops a common set of priniciples regarding the development of these technologies.

  14. Rocket based combined cycle (RBCC) propulsion systems offer additional options

    NASA Astrophysics Data System (ADS)

    Czysz, Paul A.

    The propulsion cycles presented at the 1991 IAF Congress in Montreal, and at The World Hydrogen Conference 1992 in Paris were the subject of an IAF paper for the 1992 World Space Conference in Washington DC. RBCC propulsion systems from several nations were analyzed in terms of a SSTO space launcher with a 7-Mg payload. The RBCC concept emerged from the advanced injector ramjet research of the early 1960s. The performance of the current RBCC propulsion systems such that the specific thrust of a rocket is combined with the specific impulse of an airbreather. This performance offers a new perspective to the options available. In a brief review of the present RBCC the reasons for these options are developed. The spectrum of the system options is presented in three examples, a LACE VTOL SSTO, an HTOL SSTO and a HTOL TSTO. Results using the present RBCC are dramatically different from the past concept of the Conventional Combined Cycle propulsion system, i.e., combinations of separate engines. The integration of the engine cycles into a single thermodynamically integrated system significantly changes the propulsion performance.

  15. Laser propulsion

    NASA Technical Reports Server (NTRS)

    Rom, F. E.; Putre, H. A.

    1972-01-01

    The use of an earth-based high-power laser beam to provide energy for earth-launched rocket vehicle is investigated. The laser beam energy is absorbed in an opaque propellant gas and is converted to high-specific-impulse thrust by expanding the heated propellant to space by means of a nozzle. This laser propulsion scheme can produce specific impulses of several thousand seconds. Payload to gross-weight fractions about an order of magnitude higher than those for conventional chemical earth-launched vehicles appear possible. There is a potential for a significant reduction in cost per payload mass in earth orbit.

  16. Propulsion Systems Panel deliberations

    NASA Technical Reports Server (NTRS)

    Bianca, Carmelo J.; Miner, Robert; Johnston, Lawrence M.; Bruce, R.; Dennies, Daniel P.; Dickenson, W.; Dreshfield, Robert; Karakulko, Walt; Mcgaw, Mike; Munafo, Paul M.

    1993-01-01

    The Propulsion Systems Panel was established because of the specialized nature of many of the materials and structures technology issues related to propulsion systems. This panel was co-chaired by Carmelo Bianca, MSFC, and Bob Miner, LeRC. Because of the diverse range of missions anticipated for the Space Transportation program, three distinct propulsion system types were identified in the workshop planning process: liquid propulsion systems, solid propulsion systems and nuclear electric/nuclear thermal propulsion systems.

  17. Electric vehicle propulsion alternatives

    NASA Technical Reports Server (NTRS)

    Secunde, R. R.; Schuh, R. M.; Beach, R. F.

    1983-01-01

    Propulsion technology development for electric vehicles is summarized. Analytical studies, technology evaluation, and the development of technology for motors, controllers, transmissions, and complete propulsion systems are included.

  18. Some perspectives on pulse detonation propulsion systems

    NASA Astrophysics Data System (ADS)

    Lu, F. K.; Wilson, D. R.

    Pulse detonation engines and rockets (PDE/Rs) can potentially revolutionize air breathing and rocket propulsion [1-6]. While the PDE concept is over five decades old, it has recently enjoyed renewed interest, due mostly to theoretical and computational studies indicating high cycle efficiencies. When modeled by a constant volume, Humphrey cycle, the detonation engine is found to be superior to that of existing constant pressure, Brayton cycles, with claims of as much as 10-40% improvement in specific impulse [4,7-9]. The constant volume process is derived from the Zeldovich-von Neumann-Döring (ZND) model of the detonation wave as a high strength shock wave, followed by a region of chemical reaction and a subsequent isentropic rarefaction. Amongst other advantages of the PDE is simplicity, where the PDE is easy to manufacture and requires few moving parts, with the possibility of eliminating high-pressure pumps in rocket applications, or reducing turbomachinery stages in air-breathing propulsion systems.

  19. Effect of aeroelastic-propulsive interactions on flight dynamics of a hypersonic vehicle

    NASA Technical Reports Server (NTRS)

    Raney, David L.; Mcminn, John D.; Pototzky, Anthony S.; Wooley, Christine L.

    1993-01-01

    The desire to achieve orbit-on-demand access to space with rapid turn-around capability and aircraft-like processing operations has given rise to numerous hypersonic aerospace plane design concepts which would take off horizontally from a conventional runway and employ air-breathing scramjet propulsion systems for acceleration to orbital speeds. Most of these air-breathing hypersonic vehicle concepts incorporate an elongated fuselage forebody to act as the aerodynamic compression surface for a scramjet combustor module. This type of airframe-integrated scramjet propulsion system tends to be highly sensitive to inlet conditions and angle-of-attack perturbations. Furthermore, the basic configuration of the fuselage, with its elongated and tapered forebody, produces relatively low frequency elastic modes which will cause perturbations in the combustor inlet conditions due to the oscillation of the forebody compression surface. The flexibility of the forebody compression surface, together with sensitivity of scramjet propulsion systems to inlet conditions, creates the potential for an unprecedented form of aeroelastic-propulsive interaction in which deflections of the vehicle fuselage give rise to propulsion transients, producing force and moment variations that may adversely impact the longitudinal flight dynamics and/or excite the elastic modes. These propulsive force and moment variations may have an appreciable impact on the performance, guidance, and control of a hypersonic aerospace plane. The objectives of this research are to quantify the magnitudes of propulsive force and moment perturbations resulting from elastic deformation of a representative hypersonic vehicle, and to assess the potential impact of these perturbations on the vehicle's longitudinal flight dynamics.

  20. A Technology Pathway for Airbreathing, Combined-Cycle, Horizontal Space Launch Through SR-71 Based Trajectory Modeling

    NASA Technical Reports Server (NTRS)

    Kloesel, Kurt J.; Ratnayake, Nalin A.; Clark, Casie M.

    2011-01-01

    Access to space is in the early stages of commercialization. Private enterprises, mainly under direct or indirect subsidy by the government, have been making headway into the LEO launch systems infrastructure, of small-weight-class payloads of approximately 1000 lbs. These moderate gains have emboldened the launch industry and they are poised to move into the middle-weight class (roughly 5000 lbs). These commercially successful systems are based on relatively straightforward LOX-RP, two-stage, bi-propellant rocket technology developed by the government 40 years ago, accompanied by many technology improvements. In this paper we examine a known generic LOX-RP system with the focus on the booster stage (1st stage). The booster stage is then compared to modeled Rocket-Based and Turbine-Based Combined Cycle booster stages. The air-breathing propulsion stages are based on/or extrapolated from known performance parameters of ground tested RBCC (the Marquardt Ejector Ramjet) and TBCC (the SR-71/J-58 engine) data. Validated engine models using GECAT and SCCREAM are coupled with trajectory optimization and analysis in POST-II to explore viable launch scenarios using hypothetical aerospaceplane platform obeying the aerodynamic model of the SR-71. Finally, and assessment is made of the requisite research technology advances necessary for successful commercial and government adoption of combined-cycle engine systems for space access.

  1. Kite propulsion

    NASA Astrophysics Data System (ADS)

    Du Pontavice, Emmanuel; Clanet, Christophe; Quéré, David

    2014-11-01

    Kite propulsion is one way to harvest wind energy. The typical force is 1 kilo Newton per square meter, which means that with kites in the range 100 to 1000 square meters, one is able to propel ships from the trawler to the tanker. Several scientific issues arise when trying to design kites of these sizes. They first need to take off and land autonomously. This leads to the use of kites with an inflatable structure that can be compact when stored but very rigid and light once in the air. For that matter, we studied the behavior of large inflatable structures under static and dynamic load. Then, the kite needs to stay in the air. However, it appears that under certain conditions, kites without active control tend to engage into large oscillations and eventually crash. Through wind tunnel experiments, we try to understand this flight behavior to find the conditions of stability.

  2. Rapid near-optimal trajectory generation and guidance law development for single-stage-to-orbit airbreathing vehicles

    NASA Technical Reports Server (NTRS)

    Calise, A. J.; Flandro, G. A.; Corban, J. E.

    1990-01-01

    General problems associated with on-board trajectory optimization, propulsion system cycle selection, and with the synthesis of guidance laws were addressed for an ascent to low-earth-orbit of an air-breathing single-stage-to-orbit vehicle. The NASA Generic Hypersonic Aerodynamic Model Example and the Langley Accelerator aerodynamic sets were acquired and implemented. Work related to the development of purely analytic aerodynamic models was also performed at a low level. A generic model of a multi-mode propulsion system was developed that includes turbojet, ramjet, scramjet, and rocket engine cycles. Provisions were made in the dynamic model for a component of thrust normal to the flight path. Computational results, which characterize the nonlinear sensitivity of scramjet performance to changes in vehicle angle of attack, were obtained and incorporated into the engine model. Additional trajectory constraints were introduced: maximum dynamic pressure; maximum aerodynamic heating rate per unit area; angle of attack and lift limits; and limits on acceleration both along and normal to the flight path. The remainder of the effort focused on required modifications to a previously derived algorithm when the model complexity cited above was added. In particular, analytic switching conditions were derived which, under appropriate assumptions, govern optimal transition from one propulsion mode to another for two cases: the case in which engine cycle operations can overlap, and the case in which engine cycle operations are mutually exclusive. The resulting guidance algorithm was implemented in software and exercised extensively. It was found that the approximations associated with the assumed time scale separation employed in this work are reasonable except over the Mach range from roughly 5 to 8. This phenomenon is due to the very large thrust capability of scramjets in this Mach regime when sized to meet the requirement for ascent to orbit. By accounting for flight path

  3. Solar Thermal Propulsion Concept

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Harnessing the Sun's energy through Solar Thermal Propulsion will propel vehicles through space by significantly reducing weight, complexity, and cost while boosting performance over current conventional upper stages. Another solar powered system, solar electric propulsion, demonstrates ion propulsion is suitable for long duration missions. Pictured is an artist's concept of space flight using solar thermal propulsion.

  4. Future of space propulsion

    SciTech Connect

    Weiss, R.R.; Mackay, D.S. )

    1992-03-01

    A development status-and-prospects evaluation is presented for the range of spacecraft propulsion alternatives under consideration by the USAF's Phillips Laboratory, encompassing technologies broadly characterizable as 'conventional' (solid, storable liquid, cryogenic) and 'nonconventional'. Nonconventional spacecraft propulsion system types include arcjets, magnetoplasmadynamic thrusters, solar thermal propulsion, and nuclear propulsion. The prospects for high energy density materials' application to more coventional propulsion concepts are noted.

  5. Propulsion Flight-Test Fixture

    NASA Technical Reports Server (NTRS)

    Palumbo, Nate; Vachon, M. Jake; Richwine, Dave; Moes, Tim; Creech, Gray

    2003-01-01

    NASA Dryden Flight Research Center s new Propulsion Flight Test Fixture (PFTF), designed in house, is an airborne engine-testing facility that enables engineers to gather flight data on small experimental engines. Without the PFTF, it would be necessary to obtain such data from traditional wind tunnels, ground test stands, or laboratory test rigs. Traditionally, flight testing is reserved for the last phase of engine development. Generally, engines that embody new propulsion concepts are not put into flight environments until their designs are mature: in such cases, either vehicles are designed around the engines or else the engines are mounted in or on missiles. However, a captive carry capability of the PFTF makes it possible to test engines that feature air-breathing designs (for example, designs based on the rocket-based combined cycle) economically in subscale experiments. The discovery of unknowns made evident through flight tests provides valuable information to engine designers early in development, before key design decisions are made, thereby potentially affording large benefits in the long term. This is especially true in the transonic region of flight (from mach 0.9 to around 1.2), where it can be difficult to obtain data from wind tunnels and computational fluid dynamics. In January 2002, flight-envelope expansion to verify the design and capabilities of the PFTF was completed. The PFTF was flown on a specially equipped supersonic F-15B research testbed airplane, mounted on the airplane at a center-line attachment fixture, as shown in Figure 1. NASA s F-15B testbed has been used for several years as a flight-research platform. Equipped with extensive research air-data, video, and other instrumentation systems, the airplane carries externally mounted test articles. Traditionally, the majority of test articles flown have been mounted at the centerline tank-attachment fixture, which is a hard-point (essentially, a standardized weapon-mounting fixture

  6. Developing Conceptual Hypersonic Airbreathing Engines Using Design of Experiments Methods

    NASA Technical Reports Server (NTRS)

    Ferlemann, Shelly M.; Robinson, Jeffrey S.; Martin, John G.; Leonard, Charles P.; Taylor, Lawrence W.; Kamhawi, Hilmi

    2000-01-01

    Designing a hypersonic vehicle is a complicated process due to the multi-disciplinary synergy that is required. The greatest challenge involves propulsion-airframe integration. In the past, a two-dimensional flowpath was generated based on the engine performance required for a proposed mission. A three-dimensional CAD geometry was produced from the two-dimensional flowpath for aerodynamic analysis, structural design, and packaging. The aerodynamics, engine performance, and mass properties arc inputs to the vehicle performance tool to determine if the mission goals were met. If the mission goals were not met, then a flowpath and vehicle redesign would begin. This design process might have to be performed several times to produce a "closed" vehicle. This paper will describe an attempt to design a hypersonic cruise vehicle propulsion flowpath using a Design of' Experiments method to reduce the resources necessary to produce a conceptual design with fewer iterations of the design cycle. These methods also allow for more flexible mission analysis and incorporation of additional design constraints at any point. A design system was developed using an object-based software package that would quickly generate each flowpath in the study given the values of the geometric independent variables. These flowpath geometries were put into a hypersonic propulsion code and the engine performance was generated. The propulsion results were loaded into statistical software to produce regression equations that were combined with an aerodynamic database to optimize the flowpath at the vehicle performance level. For this example, the design process was executed twice. The first pass was a cursory look at the independent variables selected to determine which variables are the most important and to test all of the inputs to the optimization process. The second cycle is a more in-depth study with more cases and higher order equations representing the design space.

  7. OTV Propulsion Issues

    NASA Technical Reports Server (NTRS)

    1984-01-01

    The statistical technology needs of aero-assist maneuvering, propulsion, and usage of cryogenic fluids were presented. Industry panels discussed the servicing of reusable space based vehicles and propulsion-vehicle interation.

  8. Beamed energy propulsion

    NASA Technical Reports Server (NTRS)

    Shoji, James M.

    1992-01-01

    Beamed energy concepts offer an alternative for an advanced propulsion system. The use of a remote power source reduces the weight of the propulsion system in flight and this, combined with the high performance, provides significant payload gains. Within the context of this study's baseline scenario, two beamed energy propulsion concepts are potentially attractive: solar thermal propulsion and laser thermal propulsion. The conceived beamed energy propulsion devices generally provide low thrust (tens of pounds to hundreds of pounds); therefore, they are typically suggested for cargo transportation. For the baseline scenario, these propulsion system can provide propulsion between the following nodes: (1) low Earth orbit to geosynchronous Earth orbit; (2) low Earth orbit to low lunar orbit; (3) low lunar orbit to low Mars orbit--only solar thermal; and (4) lunar surface to low lunar orbit--only laser thermal.

  9. Propulsion of nanowire diodes.

    PubMed

    Calvo-Marzal, Percy; Sattayasamitsathit, Sirilak; Balasubramanian, Shankar; Windmiller, Joshua R; Dao, Cuong; Wang, Joseph

    2010-03-14

    The propulsion of semiconductor diode nanowires under external AC electric field is described. Such fuel-free electric field-induced nanowire propulsion offers considerable promise for diverse technological applications. PMID:20177595

  10. Hybrid rocket propulsion

    NASA Technical Reports Server (NTRS)

    Holzman, Allen L.

    1993-01-01

    Topics addressed are: (1) comparison of the theoretical impulses; (2) comparison of the density-specific impulses; (3) general propulsion system features comparison; (4) hybrid systems, booster applications; and (5) hybrid systems, upper stage propulsion applications.

  11. Electrodynamic Tether Propulsion System

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This picture is an artist's concept of an orbiting vehicle using the Electrodynamic Tethers Propulsion System. Relatively short electrodynamic tethers can use solar power to push against a planetary magnetic field to achieve propulsion without the expenditure of propellant.

  12. Robust control of hypersonic vehicles considering propulsive and aeroelastic effects

    NASA Technical Reports Server (NTRS)

    Buschek, Harald; Calise, Anthony J.

    1993-01-01

    The influence of propulsion system variations and elastic fuselage behavior on the flight control system of an airbreathing hypersonic vehicle is investigated. Thrust vector magnitude and direction changes due to angle of attack variations affect the pitching moment. Low structural vibration frequencies may occur close to the rigid body modes influencing the angle of attack and lead to possible cross coupling. These effects are modeled as uncertainties in the context of a robust control study of a hypersonic vehicle model accelerating through Mach 8 using H-infinity and mu synthesis techniques. Various levels of uncertainty are introduced into the system. Both individual and simultaneous appearance of uncertainty are considered. The results indicate that the chosen design technique is suitable for this kind of problem provided that a fairly good knowledge of the effects mentioned above is available. The order of the designed controller is reduced but robust performance is lost which shows the need for fixed order design techniques.

  13. NASA spacecraft propulsion activities

    NASA Technical Reports Server (NTRS)

    Curran, Francis M.; Tyburski, Timothy E.; Sankovic, John M.; Jankovsky, Robert S.; Reed, Brian D.; Schneider, Steven J.; Hamley, John A.; Patterson, Michael J.; Sovey, James S.

    1997-01-01

    The NASA's activities in the development of spacecraft propulsion systems are reviewed, with emphasis on program directions and recent progress made in this domain. The recent trends towards the use of smaller spacecraft and launch vehicles call for new onboard propulsion systems. The NASA's efforts are conducted within the framework of the onboard propulsion program. The research and development work carried out in relation to the different propulsion system technologies are considered: electromagnetic systems; electrostatic systems; electrothermal systems; bipropellant systems; and monopropellant systems.

  14. Combustion Branch Website Development

    NASA Technical Reports Server (NTRS)

    Bishop, Eric

    2004-01-01

    The NASA combustion branch is a leader in developing and applying combustion science to focused aerospace propulsion systems concepts. It is widely recognized for unique facilities, analytical tools, and personnel. In order to better communicate the outstanding research being done in this Branch to the public and other research organization, a more substantial website was desired. The objective of this project was to build an up-to-date site that reflects current research in a usable and attractive manner. In order to accomplish this, information was requested from all researchers in the Combustion branch, on their professional skills and on the current projects. This information was used to fill in the Personnel and Research sections of the website. A digital camera was used to photograph all personnel and these photographs were included in the personnel section as well. The design of the site was implemented using the latest web standards: xhtml and external css stylesheets. This implementation conforms to the guidelines recommended by the w3c. It also helps to ensure that the web site is accessible by disabled users, and complies with Section 508 Federal legislation (which mandates that all Federal websites be accessible). Graphics for the new site were generated using the gimp (www.gimp.org) an open-source graphics program similar to Adobe Photoshop. Also, all graphics on the site were of a reasonable size (less than 20k, most less than 2k) so that the page would load quickly. Technologies such as Macromedia Flash and Javascript were avoided, as these only function on some clients which have the proper software installed or enabled. The website was tested on different platforms with many different browsers to ensure there were no compatibility issues. The website was tested on windows with MS IE 6, MSIE 5 , Netscape 7, Mozilla and Opera. On a Mac, the site was tested with MS IE 5 , Netscape 7 and Safari.

  15. Analysis of a Nuclear Enhanced Airbreathing Rocket for Earth to Orbit Applications

    NASA Technical Reports Server (NTRS)

    Adams, Robert B.; Landrum, D. Brian; Brown, Norman (Technical Monitor)

    2001-01-01

    The proposed engine concept is the Nuclear Enhanced Airbreathing Rocket (NEAR). The NEAR concept uses a fission reactor to thermally heat a propellant in a rocket plenum. The rocket is shrouded, thus the exhaust mixes with ingested air to provide additional thermal energy through combustion. The combusted flow is then expanded through a nozzle to provide thrust.

  16. European auxiliary propulsion, 1972

    NASA Technical Reports Server (NTRS)

    Holcomb, L. B.

    1972-01-01

    The chemical and electric auxiliary propulsion technology of the United Kingdom, France, and West Germany is discussed in detail, and the propulsion technology achievements of Italy, India, Japan, and Russia are reviewed. A comparison is presented of Shell 405 catalyst and a European spontaneous hydrazine catalyst called CNESRO I. Finally, conclusions are drawn regarding future trends in European auxiliary propulsion technology development.

  17. Directions in propulsion control

    NASA Technical Reports Server (NTRS)

    Lorenzo, Carl F.

    1990-01-01

    Discussed here is research at NASA Lewis in the area of propulsion controls as driven by trends in advanced aircraft. The objective of the Lewis program is to develop the technology for advanced reliable propulsion control systems and to integrate the propulsion control with the flight control for optimal full-system control.

  18. Solar Thermal Propulsion

    NASA Technical Reports Server (NTRS)

    Gerrish, Harold P., Jr.

    2003-01-01

    This paper presents viewgraphs on Solar Thermal Propulsion (STP). Some of the topics include: 1) Ways to use Solar Energy for Propulsion; 2) Solar (fusion) Energy; 3) Operation in Orbit; 4) Propulsion Concepts; 5) Critical Equations; 6) Power Efficiency; 7) Major STP Projects; 8) Types of STP Engines; 9) Solar Thermal Propulsion Direct Gain Assembly; 10) Specific Impulse; 11) Thrust; 12) Temperature Distribution; 13) Pressure Loss; 14) Transient Startup; 15) Axial Heat Input; 16) Direct Gain Engine Design; 17) Direct Gain Engine Fabrication; 18) Solar Thermal Propulsion Direct Gain Components; 19) Solar Thermal Test Facility; and 20) Checkout Results.

  19. Identification of propulsion systems

    NASA Technical Reports Server (NTRS)

    Merrill, Walter; Guo, Ten-Huei; Duyar, Ahmet

    1991-01-01

    This paper presents a tutorial on the use of model identification techniques for the identification of propulsion system models. These models are important for control design, simulation, parameter estimation, and fault detection. Propulsion system identification is defined in the context of the classical description of identification as a four step process that is unique because of special considerations of data and error sources. Propulsion system models are described along with the dependence of system operation on the environment. Propulsion system simulation approaches are discussed as well as approaches to propulsion system identification with examples for both air breathing and rocket systems.

  20. 2-D Airbreathing Lightcraft Engine Experiments in Quiescent Conditions

    NASA Astrophysics Data System (ADS)

    Salvador, Israel I.; Myrabo, Leik N.; Minucci, Marco A. S.; de Oliveira, Antonio C.; Toro, Paulo G. P.; Chanes, José B.; Rego, Israel S.

    2011-11-01

    Ground-breaking laser propulsion (LP) experiments were performed under quiescent conditions with a 25 cm wide, two-dimensional Lightcraft model using a Lumonics TEA-622 CO2 laser emitting ˜ 1 μs pulses. In preparation for subsequent hypersonic experiments, this static test campaign was conducted at ambient pressures of 0.06, 0.15, 0.30 and 1 bar with laser pulse energies of 150 to 230 J. Time-variant pressure distributions, generated over engine "absorption chamber" walls, were integrated to obtain total impulse and momentum coupling coefficients (Cm) representative of a single propulsion cycle. Schlieren visualization of laser-induced air breakdown and expanding blast waves was also accomplished. Surprisingly, the Cm results of 600-3000 Ns/MJ were 2.5x to 5x greater than previous results from smaller Lightcraft models; this suggests that higher static Cm performance can likely be achieved in larger scale LP engines. This research collaboration, forged between the USAF and Brazilian Air Force, was carried out at the Henry T. Nagamatsu Laboratory of Aerothermodynamics and Hypersonics in Brazil.

  1. NASA electric propulsion technology

    NASA Technical Reports Server (NTRS)

    Berkopec, F. D.; Stone, J. R.; Aston, G.

    1985-01-01

    It is pointed out that the requirements for future electric propulsion cover an extremely large range of technical and programmatic characteristics. A NASA program is to provide options for the many potential mission applications, taking into account work on electrostatic, electromagnetic, and electrothermal propulsion systems. The present paper is concerned with developments regarding the three classes of electric propulsion. Studies concerning electrostatic propulsion are concerned with ion propulsion for primary propulsion for planetary and earth-orbit transfer vehicles, stationkeeping for geosynchronous spacecraft, and ion thruster systems. In connection with investigations related to electromagnetic propulsion, attention is given to electromagnetic launchers, the Hall current thruster, and magnetoplasmadynamic thrusters. In a discussion of electrothermal developments, space station resistojets are considered along with high performance resistojets, arcjets, and a laser thruster.

  2. Details on spot remote sensing satellite propulsion unit

    NASA Astrophysics Data System (ADS)

    Corai, J. C.

    1984-03-01

    The SPOT propulsion system is described. The SPOT platform includes a propulsion module equipped with a hydrazine reaction control system (RCD). This RCS belongs to the attitude and orbit control system. It comprises essentially two branches of catalytic thrusters fed by surface tension tanks through a circuit providing their interconnection by latching insulation valves. It operates in blow-down mode. Each equipment is qualified individually.

  3. Space Propulsion Technology Program Overview

    NASA Technical Reports Server (NTRS)

    Escher, William J. D.

    1991-01-01

    The topics presented are covered in viewgraph form. Focused program elements are: (1) transportation systems, which include earth-to-orbit propulsion, commercial vehicle propulsion, auxiliary propulsion, advanced cryogenic engines, cryogenic fluid systems, nuclear thermal propulsion, and nuclear electric propulsion; (2) space platforms, which include spacecraft on-board propulsion, and station keeping propulsion; and (3) technology flight experiments, which include cryogenic orbital N2 experiment (CONE), SEPS flight experiment, and cryogenic orbital H2 experiment (COHE).

  4. Test facilities of the structural dynamics branch of NASA Lewis Research Center

    NASA Technical Reports Server (NTRS)

    Montague, Gerald T.; Kielb, Robert E.

    1988-01-01

    The NASA Lewis Research Center Structural Dynamics Branch conducts experimental and analytical research related to the structural dynamics of aerospace propulsion and power systems. The experimental testing facilities of the branch are examined. Presently there are 10 research rigs and 4 laboratories within the branch. These facilities are described along with current and past research work.

  5. Aerosciences, Aero-Propulsion and Flight Mechanics Technology Development for NASA's Next Generation Launch Technology Program

    NASA Technical Reports Server (NTRS)

    Cockrell, Charles E., Jr.

    2003-01-01

    The Next Generation Launch Technology (NGLT) program, Vehicle Systems Research and Technology (VSR&T) project is pursuing technology advancements in aerothermodynamics, aeropropulsion and flight mechanics to enable development of future reusable launch vehicle (RLV) systems. The current design trade space includes rocket-propelled, hypersonic airbreathing and hybrid systems in two-stage and single-stage configurations. Aerothermodynamics technologies include experimental and computational databases to evaluate stage separation of two-stage vehicles as well as computational and trajectory simulation tools for this problem. Additionally, advancements in high-fidelity computational tools and measurement techniques are being pursued along with the study of flow physics phenomena, such as boundary-layer transition. Aero-propulsion technology development includes scramjet flowpath development and integration, with a current emphasis on hypervelocity (Mach 10 and above) operation, as well as the study of aero-propulsive interactions and the impact on overall vehicle performance. Flight mechanics technology development is focused on advanced guidance, navigation and control (GN&C) algorithms and adaptive flight control systems for both rocket-propelled and airbreathing vehicles.

  6. Nuclear propulsion for orbital transfer

    SciTech Connect

    Beale, G.A.; Lawrence, T.J. )

    1989-06-01

    The state of the art in nuclear propulsion for orbital transfer is discussed. Cryogenic propulsion, electric propulsion, solar-thermal propulsion and direct nuclear propulsion are examined in this context. New technologies with exceptional promise are addressed, emphasizing the particle test bed nuclear engine.

  7. Expendable launch vehicle propulsion

    NASA Technical Reports Server (NTRS)

    Fuller, Paul N.

    1991-01-01

    The current status is reviewed of the U.S. Expendable Launch Vehicle (ELV) fleet, the international competition, and the propulsion technology of both domestic and foreign ELVs. The ELV propulsion technology areas where research, development, and demonstration are most needed are identified. These propulsion technology recommendations are based on the work performed by the Commercial Space Transportation Advisory Committee (COMSTAC), an industry panel established by the Dept. of Transportation.

  8. 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.

  9. Overview of electric propulsion

    NASA Astrophysics Data System (ADS)

    Daniłko, Dariusz

    2014-11-01

    Space Electric Rocket Test (SERT 1) was the first experiment in which electric propulsion device was sent into space. The present year marks the 50th anniversary of that particular mission that opened the door for the application of electric propulsion on board spacecrafts. We present an overview of existing electric propulsion technology along with the description of the most successful missions that followed the success of the SERT 1mission.

  10. Field resonance propulsion concept

    NASA Technical Reports Server (NTRS)

    Holt, A. C.

    1979-01-01

    A propulsion concept was developed based on a proposed resonance between coherent, pulsed electromagnetic wave forms, and gravitational wave forms (or space-time metrics). Using this concept a spacecraft propulsion system potentially capable of galactic and intergalactic travel without prohibitive travel times was designed. The propulsion system utilizes recent research associated with magnetic field line merging, hydromagnetic wave effects, free-electron lasers, laser generation of megagauss fields, and special structural and containment metals. The research required to determine potential, field resonance characteristics and to evaluate various aspects of the spacecraft propulsion design is described.

  11. Air-breathing hypersonic cruise - Prospects for Mach 4-7 waverider aircraft

    NASA Technical Reports Server (NTRS)

    Blankson, Isaiah M.

    1992-01-01

    In the Mach 4-7 range, waverider aircraft are considered as candidates for both short- and long-range cruise missions, as hypersonic missiles, and as high L/D highly maneuverable craft. The potential for near- and far-term application of airbreathing engines to the waverider vehicle missions and concepts is presented. Attention is focused on the cruise mission and attempts are made to compare and contrast it with the accelerator mission.

  12. 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.

  13. Sensor failure and multivariable control for airbreathing propulsion systems. Ph.D. Thesis - Dec. 1979 Final Report

    NASA Technical Reports Server (NTRS)

    Behbehani, K.

    1980-01-01

    A new sensor/actuator failure analysis technique for turbofan jet engines was developed. Three phases of failure analysis, namely detection, isolation, and accommodation are considered. Failure detection and isolation techniques are developed by utilizing the concept of Generalized Likelihood Ratio (GLR) tests. These techniques are applicable to both time varying and time invariant systems. Three GLR detectors are developed for: (1) hard-over sensor failure; (2) hard-over actuator failure; and (3) brief disturbances in the actuators. The probability distribution of the GLR detectors and the detectability of sensor/actuator failures are established. Failure type is determined by the maximum of the GLR detectors. Failure accommodation is accomplished by extending the Multivariable Nyquest Array (MNA) control design techniques to nonsquare system designs. The performance and effectiveness of the failure analysis technique are studied by applying the technique to a turbofan jet engine, namely the Quiet Clean Short Haul Experimental Engine (QCSEE). Single and multiple sensor/actuator failures in the QCSEE are simulated and analyzed and the effects of model degradation are studied.

  14. Net ion fluxes in the facultative air-breather Hoplosternum littorale (tamoata) and the obligate air-breather Arapaima gigas (pirarucu) exposed to different Amazonian waters.

    PubMed

    Baldisserotto, Bernardo; Copatti, Carlos E; Gomes, Levy C; Chagas, Edsandra C; Brinn, Richard P; Roubach, Rodrigo

    2008-12-01

    Fishes that live in the Amazon environment may be exposed to several kinds of water: black water (BW), acidic black water (pH 3.5) (ABW) and white water (WW), among others. The aim of the present study was to analyze net ion fluxes in the facultative air-breather Hoplosternum littorale (tamoata) and the obligate air-breather Arapaima gigas (pirarucu) exposed to different types of water. Fishes were acclimated in well water and later placed in individual chambers containing one type of water for ion flux measurements. After 4 h, the water in the chambers was replaced by a different type of water. The transfer of both species to ABW (independent of previous water exposure) increased net ion loss. Tamoatas transferred from ABW to BW or WW presented a net ion influx, but pirarucus showed only small changes on net ion efflux. These results allow us to conclude that tamoatas and pirarucus present differences in terms of ion regulation but that the general aspects of the ion flux are similar: (1) exposure to ABW led to net ion loss; (2) transfer from BW to WW or vice-versa induced only minor changes on net ion fluxes. These observations demonstrate that any osmoregulatory difficulties encountered by either species during changes between these latter two waters can be easily overcome. PMID:18958598

  15. Optimal propulsive efficiency of vortex enhanced propulsion

    NASA Astrophysics Data System (ADS)

    Whittlesey, Robert; Dabiri, John

    2013-11-01

    The formation of coherent vortex rings in the jet wake of a vehicle has been shown to increase the propulsive efficiency of self-propelled vehicles. However, the effect of varying vortex ring formation characteristics has not been explored for vehicles at Reynolds numbers comparable to autonomous or manned submersible vehicles. In this work, we considered a range of vortex ring formation characteristics and found a peak in the propulsive efficiency where the vortex rings generated are coincident with the onset of vortex ring pinch off. This peak corresponds to a 22% increase in the propulsive efficiency for the vortex-enhanced wake compared to a steady jet. We gratefully acknowledge the support of the Office of Naval Research Grants N000140810918 and N000141010137.

  16. Electric Propulsion Apparatus

    NASA Technical Reports Server (NTRS)

    Patterson, Michael J. (Inventor)

    2013-01-01

    An electric propulsion machine includes an ion thruster having an annular discharge chamber housing an anode having a large surface area. The ion thruster includes flat annular ion optics with a small span to gap ratio. Optionally, a second electric propulsion thruster may be disposed in a cylindrical space disposed within an interior of the annulus.

  17. NASA's Propulsion Research Laboratory

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The grand opening of NASA's new, world-class laboratory for research into future space transportation technologies located at the Marshall Space Flight Center (MSFC) in Huntsville, Alabama, took place in July 2004. The state-of-the-art Propulsion Research Laboratory (PRL) serves as a leading national resource for advanced space propulsion research. Its purpose is to conduct research that will lead to the creation and development of innovative propulsion technologies for space exploration. The facility is the epicenter of the effort to move the U.S. space program beyond the confines of conventional chemical propulsion into an era of greatly improved access to space and rapid transit throughout the solar system. The laboratory is designed to accommodate researchers from across the United States, including scientists and engineers from NASA, the Department of Defense, the Department of Energy, universities, and industry. The facility, with 66,000 square feet of useable laboratory space, features a high degree of experimental capability. Its flexibility allows it to address a broad range of propulsion technologies and concepts, such as plasma, electromagnetic, thermodynamic, and propellant propulsion. An important area of emphasis is the development and utilization of advanced energy sources, including highly energetic chemical reactions, solar energy, and processes based on fission, fusion, and antimatter. The Propulsion Research Laboratory is vital for developing the advanced propulsion technologies needed to open up the space frontier, and sets the stage of research that could revolutionize space transportation for a broad range of applications.

  18. Nuclear thermal propulsion

    NASA Technical Reports Server (NTRS)

    Bennett, Gary L.

    1991-01-01

    This document is presented in viewgraph form, and the topics covered include the following: (1) the direct fission-thermal propulsion process; (2) mission applications of direct fission-thermal propulsion; (3) nuclear engines for rocket vehicles; (4) manned mars landers; and (5) particle bed reactor design.

  19. Advanced Chemical Propulsion

    NASA Technical Reports Server (NTRS)

    Alexander, Leslie, Jr.

    2006-01-01

    Advanced Chemical Propulsion (ACP) provides near-term incremental improvements in propulsion system performance and/or cost. It is an evolutionary approach to technology development that produces useful products along the way to meet increasingly more demanding mission requirements while focusing on improving payload mass fraction to yield greater science capability. Current activities are focused on two areas: chemical propulsion component, subsystem, and manufacturing technologies that offer measurable system level benefits; and the evaluation of high-energy storable propellants with enhanced performance for in-space application. To prioritize candidate propulsion technology alternatives, a variety of propulsion/mission analyses and trades have been conducted for SMD missions to yield sufficient data for investment planning. They include: the Advanced Chemical Propulsion Assessment; an Advanced Chemical Propulsion System Model; a LOx-LH2 small pumps conceptual design; a space storables propellant study; a spacecraft cryogenic propulsion study; an advanced pressurization and mixture ratio control study; and a pump-fed vs. pressure-fed study.

  20. Laser Propulsion - Quo Vadis

    SciTech Connect

    Bohn, Willy L.

    2008-04-28

    First, an introductory overview of the different types of laser propulsion techniques will be given and illustrated by some historical examples. Second, laser devices available for basic experiments will be reviewed ranging from low power lasers sources to inertial confinement laser facilities. Subsequently, a status of work will show the impasse in which the laser propulsion community is currently engaged. Revisiting the basic relations leads to new avenues in ablative and direct laser propulsion for ground based and space based applications. Hereby, special attention will be devoted to the impact of emerging ultra-short pulse lasers on the coupling coefficient and specific impulse. In particular, laser sources and laser propulsion techniques will be tested in microgravity environment. A novel approach to debris removal will be discussed with respect to the Satellite Laser Ranging (SRL) facilities. Finally, some non technical issues will be raised aimed at the future prospects of laser propulsion in the international community.

  1. Electric propulsion cost estimation

    NASA Technical Reports Server (NTRS)

    Palaszewski, B. A.

    1985-01-01

    A parametric cost model for mercury ion propulsion modules is presented. A detailed work breakdown structure is included. Cost estimating relationships were developed for the individual subsystems and the nonhardware items (systems engineering, software, etc.). Solar array and power processor unit (PPU) costs are the significant cost drivers. Simplification of both of these subsystems through applications of advanced technology (lightweight solar arrays and high-efficiency, self-radiating PPUs) can reduce costs. Comparison of the performance and cost of several chemical propulsion systems with the Hg ion module are also presented. For outer-planet missions, advanced solar electric propulsion (ASEP) trip times and O2/H2 propulsion trip times are comparable. A three-year trip time savings over the baselined NTO/MMH propulsion system is possible with ASEP.

  2. Laser space propulsion overview

    NASA Astrophysics Data System (ADS)

    Phipps, Claude; Luke, James; Helgeson, Wesley

    2007-05-01

    In this paper, we review the history of laser space propulsion from its earliest theoretical conceptions to modern practical applicatons. Applications begin with the "Lightcraft" flights of Myrabo and include practical thrusters for satellites now completing development as well as proposals for space debris removal and direct launch of payloads into orbit. We consider laser space propulsion in the most general sense, in which laser radiation is used to propel a vehicle in space. In this sense, the topic includes early proposals for pure photon propulsion, laser ablation propulsion, as well as propulsion using lasers to detonate a gas, expel a liquid, heat and expel a gas, or even to propagate power to a remote conventional electric thruster.

  3. Large eddy simulation modelling of combustion for propulsion applications.

    PubMed

    Fureby, C

    2009-07-28

    Predictive modelling of turbulent combustion is important for the development of air-breathing engines, internal combustion engines, furnaces and for power generation. Significant advances in modelling non-reactive turbulent flows are now possible with the development of large eddy simulation (LES), in which the large energetic scales of the flow are resolved on the grid while modelling the effects of the small scales. Here, we discuss the use of combustion LES in predictive modelling of propulsion applications such as gas turbine, ramjet and scramjet engines. The LES models used are described in some detail and are validated against laboratory data-of which results from two cases are presented. These validated LES models are then applied to an annular multi-burner gas turbine combustor and a simplified scramjet combustor, for which some additional experimental data are available. For these cases, good agreement with the available reference data is obtained, and the LES predictions are used to elucidate the flow physics in such devices to further enhance our knowledge of these propulsion systems. Particular attention is focused on the influence of the combustion chemistry, turbulence-chemistry interaction, self-ignition, flame holding burner-to-burner interactions and combustion oscillations. PMID:19531515

  4. Distributed Propulsion Vehicles

    NASA Technical Reports Server (NTRS)

    Kim, Hyun Dae

    2010-01-01

    Since the introduction of large jet-powered transport aircraft, the majority of these vehicles have been designed by placing thrust-generating engines either under the wings or on the fuselage to minimize aerodynamic interactions on the vehicle operation. However, advances in computational and experimental tools along with new technologies in materials, structures, and aircraft controls, etc. are enabling a high degree of integration of the airframe and propulsion system in aircraft design. The National Aeronautics and Space Administration (NASA) has been investigating a number of revolutionary distributed propulsion vehicle concepts to increase aircraft performance. The concept of distributed propulsion is to fully integrate a propulsion system within an airframe such that the aircraft takes full synergistic benefits of coupling of airframe aerodynamics and the propulsion thrust stream by distributing thrust using many propulsors on the airframe. Some of the concepts are based on the use of distributed jet flaps, distributed small multiple engines, gas-driven multi-fans, mechanically driven multifans, cross-flow fans, and electric fans driven by turboelectric generators. This paper describes some early concepts of the distributed propulsion vehicles and the current turboelectric distributed propulsion (TeDP) vehicle concepts being studied under the NASA s Subsonic Fixed Wing (SFW) Project to drastically reduce aircraft-related fuel burn, emissions, and noise by the year 2030 to 2035.

  5. Advanced Propulsion Research Interest in Materials for Propulsion

    NASA Technical Reports Server (NTRS)

    Cole, John

    2003-01-01

    This viewgraph presentation provides an overview of material science and technology in the area of propulsion energetics. The authors note that conventional propulsion systems are near peak performance and further refinements in manufacturing, engineering design and materials will only provide incremental increases in performance. Energetic propulsion technologies could potential solve the problems of energy storage density and energy-to-thrust conversion efficiency. Topics considered include: the limits of thermal propulsion systems, the need for energetic propulsion research, emerging energetic propulsion technologies, materials research needed for advanced propulsion, and potential research opportunities.

  6. Space station propulsion technology

    NASA Technical Reports Server (NTRS)

    Norman, A. M.; Briley, G. L.; Evans, S. A.

    1987-01-01

    The objectives of this program are to provide a demonstration of hydrogen/oxygen propulsion technology readiness for the initial operational capability (IOC) space station application, specifically gaseous hydrogen/oxygen and warm hydrogen thruster concepts, and to establish a means for evolving from the IOC space station propulsion system (SSPS) to that required to support and interface with advanced station functions. These objectives were met by analytical studies and by furnishing a propulsion test bed to the Marshall Space Flight Center for testing.

  7. Nuclear Cryogenic Propulsion Stage

    NASA Technical Reports Server (NTRS)

    Houts, Michael G.; Borowski, S. K.; George, J. A.; Kim, T.; Emrich, W. J.; Hickman, R. R.; Broadway, J. W.; Gerrish, H. P.; Adams, R. B.

    2012-01-01

    The fundamental capability of Nuclear Thermal Propulsion (NTP) is game changing for space exploration. A first generation Nuclear Cryogenic Propulsion Stage (NCPS) based on NTP could provide high thrust at a specific impulse above 900 s, roughly double that of state of the art chemical engines. Characteristics of fission and NTP indicate that useful first generation systems will provide a foundation for future systems with extremely high performance. The role of the NCPS in the development of advanced nuclear propulsion systems could be analogous to the role of the DC-3 in the development of advanced aviation. Progress made under the NCPS project could help enable both advanced NTP and advanced NEP.

  8. Ion propulsion cost effectivity

    NASA Technical Reports Server (NTRS)

    Zafran, S.; Biess, J. J.

    1978-01-01

    Ion propulsion modules employing 8-cm thrusters and 30-cm thrusters were studied for Multimission Modular Spacecraft (MMS) applications. Recurring and nonrecurring cost elements were generated for these modules. As a result, ion propulsion cost drivers were identified to be Shuttle charges, solar array, power processing, and thruster costs. Cost effective design approaches included short length module configurations, array power sharing, operation at reduced thruster input power, simplified power processing units, and power processor output switching. The MMS mission model employed indicated that nonrecurring costs have to be shared with other programs unless the mission model grows. Extended performance missions exhibited the greatest benefits when compared with monopropellant hydrazine propulsion.

  9. Advanced Space Propulsion

    NASA Technical Reports Server (NTRS)

    Frisbee, Robert H.

    1996-01-01

    This presentation describes a number of advanced space propulsion technologies with the potential for meeting the need for dramatic reductions in the cost of access to space, and the need for new propulsion capabilities to enable bold new space exploration (and, ultimately, space exploitation) missions of the 21st century. For example, current Earth-to-orbit (e.g., low Earth orbit, LEO) launch costs are extremely high (ca. $10,000/kg); a factor 25 reduction (to ca. $400/kg) will be needed to produce the dramatic increases in space activities in both the civilian and government sectors identified in the Commercial Space Transportation Study (CSTS). Similarly, in the area of space exploration, all of the relatively 'easy' missions (e.g., robotic flybys, inner solar system orbiters and landers; and piloted short-duration Lunar missions) have been done. Ambitious missions of the next century (e.g., robotic outer-planet orbiters/probes, landers, rovers, sample returns; and piloted long-duration Lunar and Mars missions) will require major improvements in propulsion capability. In some cases, advanced propulsion can enable a mission by making it faster or more affordable, and in some cases, by directly enabling the mission (e.g., interstellar missions). As a general rule, advanced propulsion systems are attractive because of their low operating costs (e.g., higher specific impulse, ISD) and typically show the most benefit for relatively 'big' missions (i.e., missions with large payloads or AV, or a large overall mission model). In part, this is due to the intrinsic size of the advanced systems as compared to state-of-the-art (SOTA) chemical propulsion systems. Also, advanced systems often have a large 'infrastructure' cost, either in the form of initial R&D costs or in facilities hardware costs (e.g., laser or microwave transmission ground stations for beamed energy propulsion). These costs must then be amortized over a large mission to be cost-competitive with a SOTA

  10. Propulsion technology discipline

    NASA Technical Reports Server (NTRS)

    Jones, Lee W.

    1990-01-01

    Viewgraphs on propulsion technology discipline for Space Station Freedom are presented. Topics covered include: water electrolysis O2/H2 system; hydrazine system advancements; common technology; fluids disposal; and storable bipropellant system.

  11. Nuclear Thermal Propulsion (NTP)

    NASA Video Gallery

    NASA's history with nuclear thermal propulsion (NTP) technology goes back to the earliest days of the Agency. The Manned Lunar Rover Vehicle and the Nuclear Engine for Rocket Vehicle Applications p...

  12. Space propulsion technology overview

    NASA Technical Reports Server (NTRS)

    Pelouch, J. J., Jr.

    1979-01-01

    Chemical and electric propulsion technologies for operations beyond the shuttle's orbit with focus on future mission needs and economic effectiveness is discussed. The adequacy of the existing propulsion state-of-the-art, barriers to its utilization, benefit of technology advances, and the prognosis for advancement are the themes of the discussion. Low-thrust propulsion for large space systems is cited as a new technology with particularly high benefit. It is concluded that the shuttle's presence for at least two decades is a legitimate basis for new propulsion technology, but that this technology must be predicted on an awareness of mission requirements, economic factors, influences of other technologies, and real constraints on its utilization.

  13. Space propulsion technology overview

    NASA Technical Reports Server (NTRS)

    Pelouch, J. J., Jr.

    1979-01-01

    This paper discusses Shuttle-era, chemical and electric propulsion technologies for operations beyond the Shuttle's orbit with focus on future mission needs and economic effectiveness. The adequacy of the existing propulsion state-of-the-art, barriers to its utilization, benefit of technology advances, and the prognosis for advancement are the themes of the discussion. Low-thrust propulsion for large space systems is cited as a new technology with particularly high benefit. It is concluded that the Shuttle's presence for at least two decades is a legitimate basis for new propulsion technology, but that this technology must be predicated on an awareness of mission requirements, economic factors, influences of other technologies, and real constraints on its utilization.

  14. Solar Electric Propulsion (SEP)

    NASA Video Gallery

    Future Human Exploration requires high power solar electric propulsion vehicles to move cargo and humans beyond Low Earth Orbit, which requires large light weight arrays, high power processing, and...

  15. Solar Thermal Rocket Propulsion

    NASA Technical Reports Server (NTRS)

    Sercel, J. C.

    1986-01-01

    Paper analyzes potential of solar thermal rockets as means of propulsion for planetary spacecraft. Solar thermal rocket uses concentrated Sunlight to heat working fluid expelled through nozzle to produce thrust.

  16. Advanced propulsion on a shoestring

    SciTech Connect

    Lerner, E.J.

    1990-05-01

    Consideration is given to propulsion concepts under study by NASA Advanced Propulsion Research Program. These concepts include fusion, antimatter-matter annihilation, microwave electrothermal, and electron cyclotron resonance propulsion. Results from programs to develop fusion technologies are reviewed, including compact fusion devices and inertial confinement experiments. Problems concerning both antimatter and fusion propulsion concepts are examined and the economic issues related to propulsion research are discussed.

  17. Mission applications of electric propulsion

    NASA Technical Reports Server (NTRS)

    Atkins, K. L.

    1974-01-01

    This paper reviews the mission applications of electric propulsion. The energy requirements of candidate high-energy missions gaining in NASA priority are used to highlight the potential of electric propulsion. Mission-propulsion interfaces are examined to point out differences between chemical and electric applications. Brief comparisons between ballistic requirements and capabilities and those of electric propulsion show that electric propulsion is presently the most practical and perhaps the only technology which can accomplish missions with these energy requirements.

  18. Vehicle propulsion system

    SciTech Connect

    Ridgway, S.L.

    1981-11-17

    A hybrid vehicle propulsion system is disclosed which utilizes an internal combustion engine, an afterburner, and a steam engine in combination for improved efficiency and reduced emission of pollutants. The afterburner is provided to reduce the level of pollutants emitted and to increase the temperature of the exhaust gases from the internal combustion engine. The heat from the exhaust gases, together with the heat removed from the internal combustion cylinders, is then utilized in the steam engine to provide additional propulsion.

  19. Electric propulsion - Now

    NASA Technical Reports Server (NTRS)

    Gerpheide, J. H.

    1974-01-01

    The state of the art of electric propulsion technology is discussed with a review of the many difficult engineering problems which must be resolved before the incorporation of electric propulsion in space missions. Interferences with the spacecraft and its scientific instrumentation, conducted and radiated electromagnetic interferences during the switching and processing of large electrical loads, and mercury and other eroded materials deposition on the spacecraft are indicated among the engineering and design challenges to be overcome and resolved.

  20. Electric propulsion technology

    NASA Technical Reports Server (NTRS)

    Finke, R. C.

    1980-01-01

    The advanced electric propulsion program is directed towards lowering the specific impulse and increasing the thrust per unit of ion thruster systems. In addition, electrothermal and electromagnetic propulsion technologies are being developed to attempt to fill the gap between the conventional ion thruster and chemical rocket systems. Most of these new concepts are exagenous and are represented by rail accelerators, ablative Teflon thrusters, MPD arcs, Free Radicals, etc. Endogenous systems such as metallic hydrogen offer great promise and are also being pursued.

  1. 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.

  2. Transonic airframe propulsion integration

    NASA Technical Reports Server (NTRS)

    Coltrin, Robert E.; Sanders, Bobby W.; Bencze, Daniel P.

    1992-01-01

    This chart shows the time line for HSR propulsion/airframe integration program. HSR Phase 1 efforts are underway in both propulsion and aerodynamics. The propulsion efforts focus on cycles, inlets combustors and nozzles that will be required to reduce nitrogen oxide (NOX) at cruise and noise at takeoff and landing to acceptable levels. The aerodynamic efforts concentrate on concepts that will reduce sonic booms and increase the lift/drag (L/D) ratio for the aircraft. The Phase 2 critical propulsion component technology program will focus on large scale demonstrators of the inlet, fan, combustor, and nozzle. The hardware developed here will feed into the propulsion system program which will demonstrate overall system technology readiness, particularly in the takeoff and supersonic cruise speed ranges. The Phase 2 aerodynamic performance and vehicle integration program will provide a validated data base for advanced airframe/control/integration concepts over the full HSR speed range. The results of this program will also feed into the propulsion system demonstration program, particularly in the critical transonic arena.

  3. Ion Beam Propulsion Study

    NASA Technical Reports Server (NTRS)

    2008-01-01

    The Ion Beam Propulsion Study was a joint high-level study between the Applied Physics Laboratory operated by NASA and ASRC Aerospace at Kennedy Space Center, Florida, and Berkeley Scientific, Berkeley, California. The results were promising and suggested that work should continue if future funding becomes available. The application of ion thrusters for spacecraft propulsion is limited to quite modest ion sources with similarly modest ion beam parameters because of the mass penalty associated with the ion source and its power supply system. Also, the ion source technology has not been able to provide very high-power ion beams. Small ion beam propulsion systems were used with considerable success. Ion propulsion systems brought into practice use an onboard ion source to form an energetic ion beam, typically Xe+ ions, as the propellant. Such systems were used for steering and correction of telecommunication satellites and as the main thruster for the Deep Space 1 demonstration mission. In recent years, "giant" ion sources were developed for the controlled-fusion research effort worldwide, with beam parameters many orders of magnitude greater than the tiny ones of conventional space thruster application. The advent of such huge ion beam sources and the need for advanced propulsion systems for exploration of the solar system suggest a fresh look at ion beam propulsion, now with the giant fusion sources in mind.

  4. Solar Thermal Propulsion Test

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Researchers at the Marshall Space Flight Center (MSFC) have designed, fabricated, and tested the first solar thermal engine, a non-chemical rocket engine that produces lower thrust but has better thrust efficiency than a chemical combustion engine. MSFC turned to solar thermal propulsion in the early 1990s due to its simplicity, safety, low cost, and commonality with other propulsion systems. Solar thermal propulsion works by acquiring and redirecting solar energy to heat a propellant. The 20- by 24-ft heliostat mirror (not shown in this photograph) has a dual-axis control that keeps a reflection of the sunlight on the 18-ft diameter concentrator mirror, which then focuses the sunlight to a 4-in focal point inside the vacuum chamber. The focal point has 10 kilowatts of intense solar power. This image, taken during the test, depicts the light being concentrated into the focal point inside the vacuum chamber. As part of MSFC's Space Transportation Directorate, the Propulsion Research Center serves as a national resource for research of advanced, revolutionary propulsion technologies. The mission is to move the Nation's capabilities beyond the confines of conventional chemical propulsion into an era of aircraft-like access to Earth orbit, rapid travel throughout the solar system, and exploration of interstellar space.

  5. Hypersonic airbreathing missile concepts under study at NASA Langley Research Center

    NASA Technical Reports Server (NTRS)

    Hunt, J. L.; Johnston, P. J.; Cubbage, J. M.; Dillon, J. L.; Richie, C. B.; Marcum, D. C., Jr.; Carlson, C. H.

    1982-01-01

    The design and performance of several tactical and strategic hypersonic airbreathing missile concepts under study at the NASA Langley Research Center are discussed from an evolutionary perspective. A mid- and chin inlet missile design, constrained to the Navy's vertical box launcher, was investigated; a performance comparison is presented that is favorable to the mid-inlet approach. Parasol wing, confined flow field, and spatula-like cruise missile configurations were examined with strategic applications in mind. The preliminary results are encouraging with respect to aerodynamic and volumetric efficiency and choice of engine integration schemes.

  6. Cubic PdNP-based air-breathing cathodes integrated in glucose hybrid biofuel cells

    NASA Astrophysics Data System (ADS)

    Faggion Junior, D.; Haddad, R.; Giroud, F.; Holzinger, M.; Maduro de Campos, C. E.; Acuña, J. J. S.; Domingos, J. B.; Cosnier, S.

    2016-05-01

    Cubic Pd nanoparticles (PdNPs) were synthesized using ascorbic acid as a reducing agent and were evaluated for the catalytic oxygen reduction reaction. PdNPs were confined with multiwalled carbon nanotube (MWCNT) dispersions to form black suspensions and these inks were dropcast onto glassy carbon electrodes. Different nanoparticle sizes were synthesized and investigated upon oxygen reduction capacities (onset potential and electrocatalytic current densities) under O2 saturated conditions at varying pH values. Strong evidence of O2 diffusion limitation was demonstrated. In order to overcome oxygen concentration and diffusion limitations in solution, we used a gas diffusion layer to create a PdNP-based air-breathing cathode, which delivered -1.5 mA cm-2 at 0.0 V with an onset potential of 0.4 V. This air-breathing cathode was combined with a specially designed phenanthrolinequinone/glucose dehydrogenase-based anode to form a complete glucose/O2 hybrid bio-fuel cell providing an open circuit voltage of 0.554 V and delivering a maximal power output of 184 +/- 21 μW cm-2 at 0.19 V and pH 7.0.Cubic Pd nanoparticles (PdNPs) were synthesized using ascorbic acid as a reducing agent and were evaluated for the catalytic oxygen reduction reaction. PdNPs were confined with multiwalled carbon nanotube (MWCNT) dispersions to form black suspensions and these inks were dropcast onto glassy carbon electrodes. Different nanoparticle sizes were synthesized and investigated upon oxygen reduction capacities (onset potential and electrocatalytic current densities) under O2 saturated conditions at varying pH values. Strong evidence of O2 diffusion limitation was demonstrated. In order to overcome oxygen concentration and diffusion limitations in solution, we used a gas diffusion layer to create a PdNP-based air-breathing cathode, which delivered -1.5 mA cm-2 at 0.0 V with an onset potential of 0.4 V. This air-breathing cathode was combined with a specially designed phenanthrolinequinone

  7. Comparisons of rocket and air-breathing vehicle concepts for earth-to-orbit transportarion

    NASA Astrophysics Data System (ADS)

    Dorrington, G. E.

    1990-07-01

    To illustrate that there is ample room for improvement in earth-to-orbit reliability, transportation cost and environmental cleanliness, some future European launch vehicle concepts are presented. Varying assumptions of technology level and operational strategy offer a wide range of system/subsystem options for consideration. Specific examples cited include: the advanced reusable single-stage VTOL all-rocket vehicles, the all-liquid hydrogen-oxygen variants of Ariane 5, and the advanced one-and-a-half-stage horizontal take-off air-breathing vehicles.

  8. Stability and control characteristics of an air-breathing missile configuration having a forward located inlet

    NASA Technical Reports Server (NTRS)

    Sawyer, W. C.; Hayes, C.

    1976-01-01

    An investigation was made to determine the aerodynamic characteristics of an airbreathing missile configuration having a forward located inlet. Control was provided by cruciform tail surfaces. Aerodynamic data were obtained for the body-tail configuration alone and with planar or cruciform wings. At Mach numbers from 2.86 to 4.63, the model had internal flow. At Mach numbers from 1.70 to 2.86, the internal duct was closed, and an inlet fairing was installed to simulate boost conditions.

  9. Aerodynamic characteristics of a series of single-inlet air-breathing missile configurations

    NASA Technical Reports Server (NTRS)

    Hayes, C.

    1983-01-01

    A series of air-breathing missile configurations was investigated to provide a data base for the design of such missiles. The model could be configured with either a single axisymmetric or a two dimensional inlet located at the bottom of the body. Two tail configurations were investigated: a tri-tail and an X-tail. The tail surfaces could be deflected to provide pitch control. A wing could be located above the inlet on the center line of the model. Tests were made at supersonic Mach numbers with the inlet open and internal flow, and at subsonic-transonic Mach numbers with the internal duct closed and no internal flow.

  10. Analysis of efficiency of using hybrid propulsion for accelerating small-size rockets starting from the earth surface

    NASA Astrophysics Data System (ADS)

    Fomin, V. M.; Zvegintsev, V. I.; Mazhuls, I. I.; Shumskii, V. V.

    2010-12-01

    The flight trajectories of a hypothetical small-size rocket starting from the Earth surface and driven by hybrid propulsion, which involves a solid-propellant rocket motor (SRM) and a ramjet-type air-breathing engine (ramjet), are calculated and analyzed. The basic varied parameter is the ratio of the fuel masses used for operation of various engine types with the total fuel mass being unchanged. The objective function is the flight range of the rocket under different initial conditions. Based on a model problem considered as an example, it is demonstrated that the flight range can be substantially increased by using hybrid propulsion (SRM and ramjet), as compared with the vehicle having identical mass and size characteristics and using the SRM only.

  11. Fusion for Space Propulsion

    NASA Technical Reports Server (NTRS)

    Thio, Y. C. Francis; Schmidt, George R.; Santarius, John F.; Turchi, Peter J.; Siemon, Richard E.; Rodgers, Stephen L. (Technical Monitor)

    2002-01-01

    The need for fusion propulsion for interplanetary flights is discussed. For a propulsion system, there are three important system attributes: (1) The absolute amount of energy available, (2) the propellant exhaust velocity, and (3) the jet power per unit mass of the propulsion system (specific power). For efficient and affordable human exploration of the solar system, propellant exhaust velocity in excess of 100 km/s and specific power in excess of 10 kW/kg are required. Chemical combustion obviously cannot meet the requirement in propellant exhaust velocity. Nuclear fission processes typically result in producing energy in the form of heat that needs to be manipulated at temperatures limited by materials to about 2,800 K. Using the fission energy to heat a low atomic weight propellant produces propellant velocity of the order of 10 kinds. Alternatively the fission energy can be converted into electricity that is used to accelerate particles to high exhaust velocity. However, the necessary power conversion and conditioning equipment greatly increases the mass of the propulsion system. Fundamental considerations in waste heat rejection and power conditioning in a fission electric propulsion system place a limit on its jet specific power to the order of about 0.2 kW/kg. If fusion can be developed for propulsion, it appears to have the best of all worlds - it can provide the largest absolute amount of energy, the propellant exhaust velocity (> 100 km/s), and the high specific jet power (> 10 kW/kg). An intermediate step towards fusion propulsion might be a bimodal system in which a fission reactor is used to provide some of the energy to drive a fusion propulsion unit. There are similarities as well as differences between applying fusion to propulsion and to terrestrial electrical power generation. The similarities are the underlying plasma and fusion physics, the enabling component technologies, the computational and the diagnostics capabilities. These physics and

  12. Laser space propulsion overview

    NASA Astrophysics Data System (ADS)

    Phipps, Claude; Luke, James; Helgeson, Wesley

    2007-03-01

    In this paper, we review the history of laser space propulsion from its earliest theoretical conceptions to modern practical applicatons. Applications begin with the "Lightcraft" flights of Myrabo and include practical thrusters for satellites now completing development as well as proposals for space debris removal and direct launch of payloads into orbit. We consider laser space propulsion in the most general sense, in which laser radiation is used to propel a vehicle in space. In this sense, the topic includes early proposals for pure photon propulsion, laser ablation propulsion, as well as propulsion using lasers to detonate a gas, expel a liquid, heat and expel a gas, or even to propagate power to a remote conventional electric thruster. We also discuss the most recent advances in LSP. For the first time, it is possible to consider space propulsion engines which exhibit thrust of one to several newtons while simultaneously delivering 3,000 seconds, or greater, specific impulse. No other engine concept can do both in a compact format. These willl use onboard, rather than remote, lasers. We will review the concept of chemically augmented electric propulsion, which can provide overall thrust efficiency greater than unity while maintaining very low mass to power ratio, high mean time to failure and broad operating range. The main advantage of LSP is exhaust velocity which can be instantaneously varied from 2km/s to 30km/s, simply by varying laser pulsewidth and focal spot size on target. The laser element will probably be a diode-pumped, fiber master-oscillator-power-amplifier (MOPA) system. Liquid fuels are necessary for volumetric efficiency and reliable performance at the multi-kW optical power levels required for multi-N thrust.

  13. Gravitational Wave Propulsion

    NASA Astrophysics Data System (ADS)

    Fontana, Giorgio

    2005-02-01

    There is only one experimental proof that gravitational waves exist. With such a limitation, it may seem premature to suggest the possibility that gravitational waves can became a preferred space propulsion technique. The present understanding of the problem indicates that this is not the case. The emission of gravitational waves from astrophysical sources has been confirmed by observation, the respective detection at large distance from the source is difficult and actually we have no confirmation of a successful detection. Therefore the required preliminary discovery has been already made. This opinion is enforced by many different proposals for building the required powerful gravitational wave generators that have recently appeared in the literature and discussed at conferences. It is no longer reasonable to wait for additional confirmation of the existence of gravitational waves to start a program for building generators and testing their possible application to space travel. A vast literature shows that gravitational waves can be employed for space propulsion. Gravitational wave rockets have been proposed, non-linearity of Einstein equations allows the conversion of gravitational waves to a static gravitational field and ``artificial gravity assist'' may become a new way of travelling in space-time. Different approaches to gravitational wave propulsion are reviewed and compared. Gravitational wave propulsion is also compared to traditional rocket propulsion and an undeniable advantage can be demonstrated in terms of efficiency and performance. Testing the predictions will require gravitational wave generators with high power and wavelength short enough for producing high energy densities. Detectors designed for the specific application must be developed, taking into account that non-linearity effects are expected. The study and development of Gravitational wave propulsion is a very challenging endeavor, involving the most complex theories, sophisticated

  14. The NASA ASTP Combined-Cycle Propulsion Database Project

    NASA Technical Reports Server (NTRS)

    Hyde, Eric H.; Escher, Daric W.; Heck, Mary T.; Roddy, Jordan E.; Lyles, Garry (Technical Monitor)

    2000-01-01

    The National Aeronautics and Space Administration (NASA) communicated its long-term R&D goals for aeronautics and space transportation technologies in its 1997-98 annual progress report (Reference 1). Under "Pillar 3, Goal 9" a 25-year-horizon set of objectives has been stated for the Generation 3 Reusable Launch Vehicle ("Gen 3 RLV") class of space transportation systems. An initiative referred to as "Spaceliner 100" is being conducted to identify technology roadmaps in support of these objectives. Responsibility for running "Spaceliner 100" technology development and demonstration activities have been assigned to NASA's agency-wide Advanced Space Transportation Program (ASTP) office located at the Marshall Space Flight Center. A key technology area in which advances will be required in order to meet these objectives is propulsion. In 1996, in order to expand their focus beyond "allrocket" propulsion systems and technologies (see Appendix A for further discussion), ASTP initiated technology development and demonstration work on combined-cycle airbreathing/rocket propulsion systems (ARTT Contracts NAS8-40890 through 40894). Combined-cycle propulsion (CCP) activities (see Appendix B for definitions) have been pursued in the U.S. for over four decades, resulting in a large documented knowledge base on this subject (see Reference 2). In the fall of 1999 the Combined-Cycle Propulsion Database (CCPD) project was established with the primary purpose of collecting and consolidating CCP related technical information in support of the ASTP's ongoing technology development and demonstration program. Science Applications International Corporation (SAIC) was selected to perform the initial development of the Database under its existing support contract with MSFC (Contract NAS8-99060) because of the company's unique combination of capabilities in database development, information technology (IT) and CCP knowledge. The CCPD is summarized in the descriptive 2-page flyer appended

  15. Experimental Research on Induction Systems of an Air-breathing Valveless Pulse Detonation Engine

    NASA Astrophysics Data System (ADS)

    Wang, Zhi-wu; Chen, Xinggu; Zheng, Long-xi; Peng, Changxin; Yan, Chuan-jun

    2012-06-01

    An air-breathing valveless PDE model was designed and manufactured, which was made up of subsonic inlet, mixing chamber, ignition chamber, detonation chamber. The total pressure recovery coefficient, flux coefficient and intake resistance with six different induction systems were measured by a semi free subsonic flow field. The proof-of-principle experiments of PDE model with different induction systems were all successfully carried out, by using liquid gasoline-air mixture with low-energy system (total stored energy less than 50 mJ). The measured detonation wave pressure ratio was very close to that of C-J detonation. The air-breathing PDE model was easy to initiate and worked in good condition. The deflagration to detonation transition (DDT) and operation frequency effect on pressure traces were also investigated by experiments. The results indicated the oscillation of pressure peak at P6 enhanced with the operation frequency increased. DDT accomplished before P6 and the DDT distance was about 0.9 m (from the ignitor).

  16. Ammonia as a respiratory gas in water and air-breathing fishes.

    PubMed

    Randall, David J; Ip, Yuen K

    2006-11-01

    Ammonia is produced in the liver and excreted as NH(3) by diffusion across the gills. Elevated ammonia results in an increase in gill ventilation, perhaps via stimulation of gill oxygen chemo-receptors. Acidification of the water around the fish by carbon dioxide and acid excretion enhances ammonia excretion and constitutes "environmental ammonia detoxification". Fish have difficulties in excreting ammonia in alkaline water or high concentrations of environmental ammonia, or when out of water. The mudskipper, Periphthalmodon schlosseri, is capable of active NH(4)(+) transport, maintaining low internal levels of ammonia. To prevent a back flux of NH(3), these air-breathing fish can increase gill acid excretion and reduce the membrane NH(3) permeability by modifying the phospholipid and cholesterol compositions of their skin. Several air-breathing fish species can excrete ammonia into air through NH(3) volatilization. Some fish detoxify ammonia to glutamine or urea. The brains of some fish can tolerate much higher levels of ammonia than other animals. Studies of these fish may offer insights into the nature of ammonia toxicity in general. PMID:16731054

  17. Cubic PdNP-based air-breathing cathodes integrated in glucose hybrid biofuel cells.

    PubMed

    Faggion Junior, D; Haddad, R; Giroud, F; Holzinger, M; Maduro de Campos, C E; Acuña, J J S; Domingos, J B; Cosnier, S

    2016-05-21

    Cubic Pd nanoparticles (PdNPs) were synthesized using ascorbic acid as a reducing agent and were evaluated for the catalytic oxygen reduction reaction. PdNPs were confined with multiwalled carbon nanotube (MWCNT) dispersions to form black suspensions and these inks were dropcast onto glassy carbon electrodes. Different nanoparticle sizes were synthesized and investigated upon oxygen reduction capacities (onset potential and electrocatalytic current densities) under O2 saturated conditions at varying pH values. Strong evidence of O2 diffusion limitation was demonstrated. In order to overcome oxygen concentration and diffusion limitations in solution, we used a gas diffusion layer to create a PdNP-based air-breathing cathode, which delivered -1.5 mA cm(-2) at 0.0 V with an onset potential of 0.4 V. This air-breathing cathode was combined with a specially designed phenanthrolinequinone/glucose dehydrogenase-based anode to form a complete glucose/O2 hybrid bio-fuel cell providing an open circuit voltage of 0.554 V and delivering a maximal power output of 184 ± 21 μW cm(-2) at 0.19 V and pH 7.0. PMID:27142300

  18. Ion propulsion for communications satellites

    NASA Technical Reports Server (NTRS)

    Poeschel, R. L.

    1984-01-01

    In a recent study of potential applications for electric propulsion, it was determined that ion propulsion can provide North-South stationkeeping (NSSK) for communication satellites in geosynchronous orbit with appreciably less mass than chemical propulsion. While this finding is not new, the margin of benefit over advanced chemical propulsion technology depends strongly on the ion propulsion system specifications. Full advantage must be taken of the under-utilized stored energy available from the communication satellite's batteries. This paper describes a methodology for evaluating the benefits obtained in using ion propulsion for NSSK, both in terms of the mass reduction and its economic value.

  19. Efficiency of fish propulsion.

    PubMed

    Maertens, A P; Triantafyllou, M S; Yue, D K P

    2015-08-01

    The system efficiency of a self-propelled flexible body is ill-defined, hence we introduce the concept of quasi-propulsive efficiency, defined as the ratio of the power needed to tow a body in rigid-straight condition over the power it requires for self-propulsion, both measured for the same speed. Through examples we show that the quasi-propulsive efficiency is a rational non-dimensional metric of the propulsive fitness of fish and fish-like mechanisms, consistent with the goal to minimize fuel consumption under size and velocity constraints. We perform two-dimensional viscous simulations and apply the concept of quasi-propulsive efficiency to illustrate and discuss the efficiency of two-dimensional undulating foils employing first carangiform and then anguilliform kinematics. We show that low efficiency may be due to adverse body-propulsor hydrodynamic interactions, which cannot be accounted for by an increase in friction drag, as done previously, since at the Reynolds number Re = 5 000 considered in the simulations, pressure is a major contributor to both thrust and drag. PMID:26226349

  20. Nanosatellite Propulsion Development Program

    NASA Technical Reports Server (NTRS)

    Gagosian, J. S.; Rhee, M. S.; Zakrzwski, C. M.

    1999-01-01

    Earth-orbiting nanosatellite constellations are a unique and exciting means toward fulfilling part of the mission of the Goddard Space Flight Center (GSFC). These constellations, which may consist of several hundred 10-kg spacecraft, present unique challenges in the area of propulsion. Many mission concepts require significant delta-v and attitude control capability to reside in the nanosatellites. In response to requirements from mission feasibility studies, such as the Magnetospheric Constellation study, the GSFC has initiated industry and government partnerships to develop enabling propulsion technologies. The largest challenge has been to meet the power constraints of nanosatellites. These power issues, combined with the high thrust required by many of the missions studied, have led the GSFC to concentrate its efforts on chemical propulsion technology. Electric propulsion technologies capable of performing efficiently at very low power are also of interest to the GSFC as potential candidates for nanosatellite formation flying missions. This paper provides the status of specific industrial or government partnerships undertaken by the GSFC to develop nano/micro propulsion components. Three specific technologies are described in detail: 1) Nanosatellite Solid Rocket Motor Prototype 2) Ultra-Low-Power Cold Gas Thruster for Spin-Axis Precession 3) Micro-Machined Solid-Propellant Gas Generators.

  1. Laser Propulsion Standardization Issues

    SciTech Connect

    Scharring, Stefan; Eckel, Hans-Albert; Roeser, Hans-Peter; Sinko, John E.; Sasoh, Akihiro

    2010-10-08

    It is a relevant issue in the research on laser propulsion that experimental results are treated seriously and that meaningful scientific comparison is possible between groups using different equipment and measurement techniques. However, critical aspects of experimental measurements are sparsely addressed in the literature. In addition, few studies so far have the benefit of independent confirmation by other laser propulsion groups. In this paper, we recommend several approaches towards standardization of published laser propulsion experiments. Such standards are particularly important for the measurement of laser ablation pulse energy, laser spot area, imparted impulse or thrust, and mass removal during ablation. Related examples are presented from experiences of an actual scientific cooperation between NU and DLR. On the basis of a given standardization, researchers may better understand and contribute their findings more clearly in the future, and compare those findings confidently with those already published in the laser propulsion literature. Relevant ISO standards are analyzed, and revised formats are recommended for application to laser propulsion studies.

  2. Mechanisms of Electric Propulsion

    NASA Astrophysics Data System (ADS)

    Fisch, Nathaniel J.

    2004-11-01

    The technology of electric propulsion evolved to overcome the high propellant weight associated with propulsion by chemical means. As opposed to ejecting propellant at velocities of kilometers per second, exhaust velocities of plasma at tens of kilometers per second and more could be accomplished through electrical means. Although higher exhaust velocities require higher on-board power, the reduced propellant requirements facilitate a large variety of space transportation missions, such as orbit-raising, station-keeping, or other propulsion missions requiring the conservation of propellant mass such as interplanetary flight. To produce thrust by the application of electric forces, plasma can be accelerated directly, or ions can be accelerated and then neutralized to form flowing neutral plasma. The different mechanisms of acceleration are embodied in such thrust devices as ion thrusters, Hall thrusters, magnetoplasmadynamic thrusters, or arcjets. In each method of electric propulsion, different technological limitations arise from basic plasma properties. This talk reviews the basic acceleration mechanisms at play in contemporary means of electric propulsion within the broader context of accelerating plasma by any means.

  3. Nuclear concepts/propulsion

    NASA Technical Reports Server (NTRS)

    Miller, Thomas J.

    1993-01-01

    Nuclear thermal and nuclear electric propulsion systems will enable and/or enhance important space exploration missions to the moon and Mars. Current efforts are addressing certain research areas, although NASA and DOE still have much work yet to do. Relative to chemical systems, nuclear thermal propulsion offers the potential of reduced vehicle weight, wider launch windows. and shorter transit times, even without aerobrakes. This would improve crew safety by reducing their exposure to cosmic radiation. Advanced materials and structures will be an important resource in responding to the challenges posed by safety and test facility requirements, environmental concerns, high temperature fuels and the high radiation, hot hydrogen environment within nuclear thermal propulsion systems. Nuclear electric propulsion (NEP) has its own distinct set of advantages relative to chemical systems. These include low resupply mass, the availability of large amounts of onboard electric power for other uses besides propulsion, improved launch windows, and the ability to share technology with surface power systems. Development efforts for NEP reactors will emphasize long life operation of compact designs. This will require designs that provide high fuel burnup and high temperature operation along with personnel and environmental safety.

  4. Propulsion IVHM Technology Experiment

    NASA Technical Reports Server (NTRS)

    Chicatelli, Amy K.; Maul, William A.; Fulton, Christopher E.

    2006-01-01

    The Propulsion IVHM Technology Experiment (PITEX) successfully demonstrated real-time fault detection and isolation of a virtual reusable launch vehicle (RLV) main propulsion system (MPS). Specifically, the PITEX research project developed and applied a model-based diagnostic system for the MPS of the X-34 RLV, a space-launch technology demonstrator. The demonstration was simulation-based using detailed models of the propulsion subsystem to generate nominal and failure scenarios during captive carry, which is the most safety-critical portion of the X-34 flight. Since no system-level testing of the X-34 Main Propulsion System (MPS) was performed, these simulated data were used to verify and validate the software system. Advanced diagnostic and signal processing algorithms were developed and tested in real time on flight-like hardware. In an attempt to expose potential performance problems, the PITEX diagnostic system was subjected to numerous realistic effects in the simulated data including noise, sensor resolution, command/valve talkback information, and nominal build variations. In all cases, the PITEX system performed as required. The research demonstrated potential benefits of model-based diagnostics, defined performance metrics required to evaluate the diagnostic system, and studied the impact of real-world challenges encountered when monitoring propulsion subsystems.

  5. 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.

  6. Nuclear-electric propulsion - Manned Mars propulsion options

    NASA Technical Reports Server (NTRS)

    Palaszewski, Bryan; Brophy, John; King, David

    1989-01-01

    Nuclear-electric propulsion can significantly reduce the launch mass for manned Mars missions. By using high-specific-impulse (lsp) electric propulsion systems with advanced nuclear reactors, the total mass-to-orbit for a series of manned Mars flight is reduced. Propulsion technologies required for the manned Mars mission are described. Multi-megawatt Ion and Magneto-Plasma-Dynamic (MPD) propulsion thrusters, Power-Processing Units and nuclear power source are needed. Xenon (Xe)-Ion and MPD thruster performance are detailed. Mission analyses for several Mars mission options are addressed. Both MPD and Ion propulsion were investigated. A four-megawatt propulsion system power level was assumed. Mass comparisons for all-chemical oxygen/hydrogen propulsion missions and combined chemical and nuclear-electric propulsion Mars fleets are included. With fleets of small nuclear-electric vehicles, short trip times to Mars are also enabled.

  7. Electric Propulsion Applications and Impacts

    NASA Technical Reports Server (NTRS)

    Curran, Frank M.; Wickenheiser, Timothy J.

    1996-01-01

    Most space missions require on-board propulsion systems and these systems are often dominant spacecraft mass drivers. Presently, on-board systems account for more than half the injected mass for commercial communications systems and even greater mass fractions for ambitious planetary missions. Anticipated trends toward the use of both smaller spacecraft and launch vehicles will likely increase pressure on the performance of on-board propulsion systems. The acceptance of arcjet thrusters for operational use on commercial communications satellites ushered in a new era in on-board propulsion and exponential growth of electric propulsion across a broad spectrum of missions is anticipated. NASA recognizes the benefits of advanced propulsion and NASA's Office of Space Access and Technology supports an aggressive On-Board Propulsion program, including a strong electric propulsion element, to assure the availability of high performance propulsion systems to meet the goals of the ambitious missions envisioned in the next two decades. The program scope ranges from fundamental research for future generation systems through specific insertion efforts aimed at near term technology transfer. The On-Board propulsion program is committed to carrying technologies to levels required for customer acceptance and emphasizes direct interactions with the user community and the development of commercial sources. This paper provides a discussion of anticipated missions, propulsion functions, and electric propulsion impacts followed by an overview of the electric propulsion element of the NASA On-Board Propulsion program.

  8. Advanced rocket propulsion

    NASA Technical Reports Server (NTRS)

    Obrien, Charles J.

    1993-01-01

    Existing NASA research contracts are supporting development of advanced reinforced polymer and metal matrix composites for use in liquid rocket engines of the future. Advanced rocket propulsion concepts, such as modular platelet engines, dual-fuel dual-expander engines, and variable mixture ratio engines, require advanced materials and structures to reduce overall vehicle weight as well as address specific propulsion system problems related to elevated operating temperatures, new engine components, and unique operating processes. High performance propulsion systems with improved manufacturability and maintainability are needed for single stage to orbit vehicles and other high performance mission applications. One way to satisfy these needs is to develop a small engine which can be clustered in modules to provide required levels of total thrust. This approach should reduce development schedule and cost requirements by lowering hardware lead times and permitting the use of existing test facilities. Modular engines should also reduce operational costs associated with maintenance and parts inventories.

  9. Free radical propulsion concept

    NASA Technical Reports Server (NTRS)

    Hawkins, C. E.; Nakanishi, S.

    1981-01-01

    A free radical propulsion concept utilizing the recombination energy of dissociated low molecular weight gases to produce thrust was examined. The concept offered promise of a propulsion system operating at a theoretical impulse, with hydrogen, as high as 2200 seconds at high thrust to power ratio, thus filling the gas existing between chemical and electrostatic propulsion capabilities. Microwave energy used to dissociate a continuously flowing gas was transferred to the propellant via three body recombination for conversion to propellant kinetic energy. Power absorption by the microwave plasma discharge was in excess of 90 percent over a broad range of pressures. Gas temperatures inferred from gas dynamic equations showed much higher temperatures from microwave heating than from electrothermal heating. Spectroscopic analysis appeared to corroborate the inferred temperatures of one of the gases tested.

  10. Nuclear electric propulsion

    NASA Technical Reports Server (NTRS)

    Keaton, Paul W.; Tubb, David J.

    1986-01-01

    The feasibility is investigated of using nuclear electric propulsion (NEP) for slow freighter ships traveling from a 500 km low Earth orbit (LEO) to the Moon's orbit about the Earth, and on to Mars. NEP is also shown to be feasible for transporting people to Mars on long conjunction-class missions lasting about nine months one way, and on short sprint missions lasting four months one way. Generally, it was not attempted to optimize ion exhaust velocities, but rather suitable parameters to demonstrate NEP feasibility were chosen. Various combinations of missions are compared with chemical and nuclear thermal propulsion (NTR) systems. Typically, NEP and NTR can accomplish the same lifting task with similar mass in LEO. When compared to chemical propulsion, NEP was found to accomplish the same missions with 40% less mass in LEO. These findings are sufficiently encouraging as to merit further studies with optimum systems.

  11. Space station propulsion technology

    NASA Technical Reports Server (NTRS)

    Briley, G. L.

    1986-01-01

    The progress on the Space Station Propulsion Technology Program is described. The objectives are to provide a demonstration of hydrogen/oxygen propulsion technology readiness for the Initial Operating Capability (IOC) space station application, specifically gaseous hydrogen/oxygen and warm hydrogen thruster concepts, and to establish a means for evolving from the IOC space station propulsion to that required to support and interface with advanced station functions. The evaluation of concepts was completed. The accumulator module of the test bed was completed and, with the microprocessor controller, delivered to NASA-MSFC. An oxygen/hydrogen thruster was modified for use with the test bed and successfully tested at mixture ratios from 4:1 to 8:1.

  12. Fusion for Space Propulsion

    NASA Technical Reports Server (NTRS)

    Thio, Y. C. Francis; Schafer, Charles (Technical Monitor)

    2001-01-01

    There is little doubt that humans will attempt to explore and develop the solar system in this century. A large amount of energy will be required for accomplishing this. The need for fusion propulsion is discussed. For a propulsion system, there are three important thermodynamical attributes: (1) The absolute amount of energy available, (2) the propellant exhaust velocity, and (3) the jet power per unit mass of the propulsion system (specific power). For human exploration and development of the solar system, propellant exhaust velocity in excess of 100 km/s and specific power in excess of 10 kW/kg are required. Chemical combustion can produce exhaust velocity up to about 5 km/s. Nuclear fission processes typically result in producing energy in the form of heat that needs to be manipulated at temperatures limited by materials to about 2,800 K. Using the energy to heat a hydrogen propellant increases the exhaust velocity by only a factor of about two. Alternatively the energy can be converted into electricity which is then used to accelerate particles to high exhaust velocity. The necessary power conversion and conditioning equipment, however, increases the mass of the propulsion system for the same jet power by more than two orders of magnitude over chemical system, thus greatly limits the thrust-to-weight ratio attainable. The principal advantage of the fission process is that its development is relatively mature and is available right now. If fusion can be developed, fusion appears to have the best of all worlds in terms of propulsion - it can provide the absolute amount, the propellant exhaust velocity, and the high specific jet power. An intermediate step towards pure fusion propulsion is a bimodal system in which a fission reactor is used to provide some of the energy to drive a fusion propulsion unit. The technical issues related to fusion for space propulsion are discussed. The technical priorities for developing and applying fusion for propulsion are

  13. Advanced rocket propulsion

    NASA Astrophysics Data System (ADS)

    Obrien, Charles J.

    1993-02-01

    Existing NASA research contracts are supporting development of advanced reinforced polymer and metal matrix composites for use in liquid rocket engines of the future. Advanced rocket propulsion concepts, such as modular platelet engines, dual-fuel dual-expander engines, and variable mixture ratio engines, require advanced materials and structures to reduce overall vehicle weight as well as address specific propulsion system problems related to elevated operating temperatures, new engine components, and unique operating processes. High performance propulsion systems with improved manufacturability and maintainability are needed for single stage to orbit vehicles and other high performance mission applications. One way to satisfy these needs is to develop a small engine which can be clustered in modules to provide required levels of total thrust. This approach should reduce development schedule and cost requirements by lowering hardware lead times and permitting the use of existing test facilities. Modular engines should also reduce operational costs associated with maintenance and parts inventories.

  14. Nuclear electric propulsion

    NASA Astrophysics Data System (ADS)

    Keaton, Paul W.; Tubb, David J.

    1986-05-01

    The feasibility is investigated of using nuclear electric propulsion (NEP) for slow freighter ships traveling from a 500 km low Earth orbit (LEO) to the Moon's orbit about the Earth, and on to Mars. NEP is also shown to be feasible for transporting people to Mars on long conjunction-class missions lasting about nine months one way, and on short sprint missions lasting four months one way. Generally, it was not attempted to optimize ion exhaust velocities, but rather suitable parameters to demonstrate NEP feasibility were chosen. Various combinations of missions are compared with chemical and nuclear thermal propulsion (NTR) systems. Typically, NEP and NTR can accomplish the same lifting task with similar mass in LEO. When compared to chemical propulsion, NEP was found to accomplish the same missions with 40% less mass in LEO. These findings are sufficiently encouraging as to merit further studies with optimum systems.

  15. Advanced Chemical Propulsion Study

    NASA Technical Reports Server (NTRS)

    Woodcock, Gordon; Byers, Dave; Alexander, Leslie A.; Krebsbach, Al

    2004-01-01

    A study was performed of advanced chemical propulsion technology application to space science (Code S) missions. The purpose was to begin the process of selecting chemical propulsion technology advancement activities that would provide greatest benefits to Code S missions. Several missions were selected from Code S planning data, and a range of advanced chemical propulsion options was analyzed to assess capabilities and benefits re these missions. Selected beneficial applications were found for higher-performing bipropellants, gelled propellants, and cryogenic propellants. Technology advancement recommendations included cryocoolers and small turbopump engines for cryogenic propellants; space storable propellants such as LOX-hydrazine; and advanced monopropellants. It was noted that fluorine-bearing oxidizers offer performance gains over more benign oxidizers. Potential benefits were observed for gelled propellants that could be allowed to freeze, then thawed for use.

  16. Space transportation propulsion USSR launcher technology, 1990

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Space transportation propulsion U.S.S.R. launcher technology is discussed. The following subject areas are covered: Energia background (launch vehicle summary, Soviet launcher family) and Energia propulsion characteristics (booster propulsion, core propulsion, and growth capability).

  17. Supersonic laser propulsion.

    PubMed

    Rezunkov, Yurii; Schmidt, Alexander

    2014-11-01

    To produce supersonic laser propulsion, a new technique based on the interaction of a laser-ablated jet with supersonic gas flow in a nozzle is proposed. It is shown that such parameters of the jet, such as gas-plasma pressure and temperature in the ablation region as well as the mass consumption rate of the ablated solid propellant, are characteristic in this respect. The results of numerical simulations of the supersonic laser propulsion are presented for two types of nozzle configuration. The feasibility to achieve the momentum coupling coefficient of C(m)∼10(-3) N/W is shown. PMID:25402938

  18. Electric Propulsion Orbital Platform

    NASA Technical Reports Server (NTRS)

    Friedly, V. J.; Ruyten, Wilhelmus M.; Litchford, R. J.; Garrison, G. W.

    1993-01-01

    This paper describes the Electric Propulsion Orbital Platform (EPOP), of which the primary objective is to provide an instrumented platform for testing electric propulsion devices in space. It is anticipated that the first flight, EPOP-1, will take place on the Shuttle-deployed Wake Shield Facility in 1996, and will be designed around a commercial 1.8 kW arcjet system which will be operated on gaseous hydrogen propellant. Specific subsystems are described, including the arcjet system, the propellant and power systems, and the diagnostics systems.

  19. Electric propulsion: Experimental research

    NASA Technical Reports Server (NTRS)

    Ruyten, W. M.; Friedly, V. J.; Keefer, D.

    1992-01-01

    This paper describes experimental electric propulsion research which was carried out at the University of Tennessee Space Institute with support from the Center for Space Transportation and Applied Research. Specifically, a multiplexed laser induced fluorescence (LIF) technique for obtaining vector velocities, Doppler temperatures, and relative number densities in the exhaust plumes from electric propulsion devices is described, and results are presented that were obtained on a low power argon arcjet. Also, preliminary Langmuir probe measurements on an ion source are described, and an update on the vacuum facility is presented.

  20. Electric Propulsion: Experimental Research

    NASA Technical Reports Server (NTRS)

    Ruyten, W. M.; Friedly, V. J.; Keefer, D.

    1995-01-01

    This paper describes experimental electric propulsion research which was carried out at the University of Tennessee Space Institute with support from the Center for Space Transportation and Applied Research. Specifically, a multiplexed LIF technique for obtaining vector velocities, Doppler temperatures, and relative number densities in the exhaust plumes form electric propulsion devices is described, and results are presented that were obtained on a low power argon arcjet. Also, preliminary Langmuir probe measurements on an ion source are described, and an update on the vacuum facility is presented.

  1. Propulsion controlled aircraft computer

    NASA Technical Reports Server (NTRS)

    Cogan, Bruce R. (Inventor)

    2010-01-01

    A low-cost, easily retrofit Propulsion Controlled Aircraft (PCA) system for use on a wide range of commercial and military aircraft consists of an propulsion controlled aircraft computer that reads in aircraft data including aircraft state, pilot commands and other related data, calculates aircraft throttle position for a given maneuver commanded by the pilot, and then displays both current and calculated throttle position on a cockpit display to show the pilot where to move throttles to achieve the commanded maneuver, or is automatically sent digitally to command the engines directly.

  2. Focused technology: Nuclear propulsion

    NASA Technical Reports Server (NTRS)

    Miller, Thomas J.

    1991-01-01

    The topics presented are covered in viewgraph form and include: nuclear thermal propulsion (NTP), which challenges (1) high temperature fuel and materials, (2) hot hydrogen environment, (3) test facilities, (4) safety, (5) environmental impact compliance, and (6) concept development, and nuclear electric propulsion (NEP), which challenges (1) long operational lifetime, (2) high temperature reactors, turbines, and radiators, (3) high fuel burn-up reactor fuels, and designs, (4) efficient, high temperature power conditioning, (5) high efficiency, and long life thrusters, (6) safety, (7) environmental impact compliance, and (8) concept development.

  3. Nuclear thermal propulsion program overview

    NASA Technical Reports Server (NTRS)

    Bennett, Gary L.

    1991-01-01

    Nuclear thermal propulsion program is described. The following subject areas are covered: lunar and Mars missions; national space policy; international cooperation in space exploration; propulsion technology; nuclear rocket program; and budgeting.

  4. Experimental Research on Plasma Induced by TEA CO2 Laser Propulsion

    NASA Astrophysics Data System (ADS)

    Lu, Hong; Cheng, Zuhai; Zuo, Duluo; Zhai, Bingjie; Yu, Liangying; Zhu, Haihong

    2008-04-01

    Results in the air-breathing propulsion experiments with a parabolic light craft and a self-made UV-preionized 100 J TEA CO2 laser device are presented. Air disturbance and the spectrum of the plasma after the interaction of pulsed laser radiation with the light craft were studied. It was found that the focal length of the parabolic light craft had a significant effect on the air-disturbance. Two shock waves were detected for the longer focal length, while only one shock wave detected for the short focal length. The spectrum of the laser-induced plasma, the distribution of the characteristic lines, and the temporal behaviors of the air plasma were studied in detail. The results showed that, the evolution of the laser-induced plasma lasted 20 μs, and the plasma spectrum would reach the maximum intensity at 7 μs.

  5. Methods for Prediction of High-Speed Reacting Flows in Aerospace Propulsion

    NASA Technical Reports Server (NTRS)

    Drummond, J. Philip

    2014-01-01

    Research to develop high-speed airbreathing aerospace propulsion systems was underway in the late 1950s. A major part of the effort involved the supersonic combustion ramjet, or scramjet, engine. Work had also begun to develop computational techniques for solving the equations governing the flow through a scramjet engine. However, scramjet technology and the computational methods to assist in its evolution would remain apart for another decade. The principal barrier was that the computational methods needed for engine evolution lacked the computer technology required for solving the discrete equations resulting from the numerical methods. Even today, computer resources remain a major pacing item in overcoming this barrier. Significant advances have been made over the past 35 years, however, in modeling the supersonic chemically reacting flow in a scramjet combustor. To see how scramjet development and the required computational tools finally merged, we briefly trace the evolution of the technology in both areas.

  6. Operating system for a real-time multiprocessor propulsion system simulator. User's manual

    NASA Technical Reports Server (NTRS)

    Cole, G. L.

    1985-01-01

    The NASA Lewis Research Center is developing and evaluating experimental hardware and software systems to help meet future needs for real-time, high-fidelity simulations of air-breathing propulsion systems. Specifically, the real-time multiprocessor simulator project focuses on the use of multiple microprocessors to achieve the required computing speed and accuracy at relatively low cost. Operating systems for such hardware configurations are generally not available. A real time multiprocessor operating system (RTMPOS) that supports a variety of multiprocessor configurations was developed at Lewis. With some modification, RTMPOS can also support various microprocessors. RTMPOS, by means of menus and prompts, provides the user with a versatile, user-friendly environment for interactively loading, running, and obtaining results from a multiprocessor-based simulator. The menu functions are described and an example simulation session is included to demonstrate the steps required to go from the simulation loading phase to the execution phase.

  7. Modification to the Langley 8-foot high temperature tunnel for hypersonic propulsion testing

    NASA Technical Reports Server (NTRS)

    Reubush, D. E.; Puster, R. L.; Kelly, H. N.

    1987-01-01

    Described are the modifications currently under way to the Langley 8-Foot High Temperature Tunnel to produce a new, unique national resource for testing hypersonic air-breathing propulsion systems. The current tunnel, which has been used for aerothermal loads and structures research since its inception, is being modified with the addition of a LOX system to bring the oxygen content of the test medium up to that of air, the addition of alternate Mach number capability (4 and 5) to augment the current M=7 capability, improvements to the tunnel hardware to reduce maintenance downtime, the addition of a hydrogen system to allow the testing of hydrogen powered engines, and a new data system to increase both the quantity and quality of the data obtained.

  8. Modification to the Langley 8-foot high temperature tunnel for hypersonic propulsion testing

    NASA Astrophysics Data System (ADS)

    Reubush, D. E.; Puster, R. L.; Kelly, H. N.

    1987-06-01

    Described are the modifications currently under way to the Langley 8-Foot High Temperature Tunnel to produce a new, unique national resource for testing hypersonic air-breathing propulsion systems. The current tunnel, which has been used for aerothermal loads and structures research since its inception, is being modified with the addition of a LOX system to bring the oxygen content of the test medium up to that of air, the addition of alternate Mach number capability (4 and 5) to augment the current M=7 capability, improvements to the tunnel hardware to reduce maintenance downtime, the addition of a hydrogen system to allow the testing of hydrogen powered engines, and a new data system to increase both the quantity and quality of the data obtained.

  9. Propulsion Controls and Diagnostics Research at NASA Glenn Research Center

    NASA Technical Reports Server (NTRS)

    Garg, Sanjay

    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. Also the propulsion systems required to enable the National Aeronautics and Space Administration (NASA) Vision for Space Exploration in an affordable manner will need to have high reliability, safety and autonomous operation capability. The Controls and Dynamics Branch (CDB) at NASA 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. This paper describes the current activities of the CDB under the NASA Aeronautics Research and Exploration Systems Missions. The programmatic structure of the CDB activities is described along with a brief overview of each of the CDB tasks including research objectives, technical challenges, and recent accomplishments. These tasks include active control of propulsion system components, intelligent propulsion diagnostics and control for reliable fault identification and accommodation, distributed engine control, and investigations into unsteady propulsion systems.

  10. The NASA Electric Propulsion Program

    NASA Technical Reports Server (NTRS)

    Stone, James R.; Byers, David C.; King, David Q.

    1988-01-01

    The NASA OAST Propulsion, Power, and Energy Division supports an electric propulsion program aimed at providing benefits to a broad class of missions. Concepts which have the potential to enable or significantly benefit space exploration and exploitation are identified and advanced toward application in the near and far term. This paper summarizes recent program progress in mission/system analysis; in electrothermal, electrostatic, and electromagnetic propulsion technologies; and in propulsion/spacecraft integration.

  11. General Aviation Propulsion

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Programs exploring and demonstrating new technologies in general aviation propulsion are considered. These programs are the quiet, clean, general aviation turbofan (QCGAT) program; the general aviation turbine engine (GATE) study program; the general aviation propeller technology program; and the advanced rotary, diesel, and reciprocating engine programs.

  12. Rarefaction wave gun propulsion

    NASA Astrophysics Data System (ADS)

    Kathe, Eric Lee

    A new species of gun propulsion that dramatically reduces recoil momentum imparted to the gun is presented. First conceived by the author on 18 March 1999, the propulsion concept is explained, a methodology for the design of a reasonable apparatus for experimental validation using NATO standard 35mm TP anti-aircraft ammunition is developed, and the experimental results are presented. The firing results are juxtaposed by a simple interior ballistic model to place the experimental findings into a context within which they may better be understood. Rarefaction wave gun (RAVEN) propulsion is an original contribution to the field of armament engineering. No precedent is known, and no experimental results of such a gun have been published until now. Recoil reduction in excess of 50% was experimentally achieved without measured loss in projectile velocity. RAVEN achieves recoil reduction by means of a delayed venting of the breech of the gun chamber that directs the high enthalpy propellant gases through an expansion nozzle to generate forward thrust that abates the rearward momentum applied to the gun prior to venting. The novel feature of RAVEN, relative to prior recoilless rifles, is that sufficiently delayed venting results in a rarefaction wave that follows the projectile though the bore without catching it. Thus, the projectile exits the muzzle without any compromise to its propulsion performance relative to guns that maintain a sealed chamber.

  13. Turboprop Propulsion Mechanic.

    ERIC Educational Resources Information Center

    Chanute AFB Technical Training Center, IL.

    This instructional package consists of a plan of instruction, glossary, and student handouts and exercises for use in training Air Force personnel to become turboprop propulsion mechanics. Addressed in the individual lessons of the course are the following: common hand tools, hardware, measuring devices, and safety wiring; aircraft and engine…

  14. Solar Electric Propulsion

    NASA Technical Reports Server (NTRS)

    LaPointe, Michael

    2006-01-01

    The Solar Electric Propulsion (SEP) technology area is tasked to develop near and mid-term SEP technology to improve or enable science mission capture while minimizing risk and cost to the end user. The solar electric propulsion investments are primarily driven by SMD cost-capped mission needs. The technology needs are determined partially through systems analysis tasks including the recent "Re-focus Studies" and "Standard Architecture Study." These systems analysis tasks transitioned the technology development to address the near term propulsion needs suitable for cost-capped open solicited missions such as Discovery and New Frontiers Class missions. Major SEP activities include NASA's Evolutionary Xenon Thruster (NEXT), implementing a Standard Architecture for NSTAR and NEXT EP systems, and developing a long life High Voltage Hall Accelerator (HiVHAC). Lower level investments include advanced feed system development and xenon recovery testing. Future plans include completion of ongoing ISP development activities and evaluating potential use of commercial electric propulsion systems for SMD applications. Examples of enhanced mission capability and technology readiness dates shall be discussed.

  15. NASA Now: Propulsion

    NASA Video Gallery

    In this episode of NASA Now, you’ll visit NASA’s Spacecraft Propulsion Research Facility, called B-2, at NASA Plum Brook Station. You’ll meet Dr. Louis Povinelli and Brian Jones who explain w...

  16. Characterizing Branched Flow

    NASA Astrophysics Data System (ADS)

    Drury, Byron; Klales, Anna; Heller, Eric

    2014-03-01

    Branched flow appears in a variety of physical systems spanning length scales from microns to thousands of kilometers. For instance, it plays an important role in both electron transport in two dimensional electron gases and the propagation of tsunamis in the ocean. Branches have typically been identified with caustics in the theoretical literature, but concentrations of flux recognizable as branches can arise from other mechanisms. We propose a generalized definition of branching based on a local measure of the stability of trajectories. We analytically and numerically study the characteristics of Hamiltonian flow in phase space and characterize the relationship between branch formation and trajectory stability.

  17. Advanced Chemical Propulsion

    NASA Astrophysics Data System (ADS)

    Alexander, L.

    2004-11-01

    Improving the performance and reliability characteristics of chemical propulsion systems requires research and testing of higher-performance propellants, higher efficiency thrusters, cryogenics technology, lightweight components and advancements in propulsion system design and assessment. Propellants are being investigated to identify practical combinations with higher efficiencies and better thermal properties to reduce thermal control requirements. This includes combinations with modest increases, such as LOX-hydrazine, as well as a new evaluation of major improvements available from fluorine-bearing oxidizers. Practical ways of implementing cryogenic propulsion to further increase efficiency are also being studied. Some potential advances include small pump-fed engines, and improvements in cryocooler technology and tank pressure control. Gelled propellants will be tested to determine the practicality of letting propellants freeze at low environmental temperatures and thawing them only when required for use. The propellant tank is typically the single highest non-expendable mass in a chemical propulsion system. Lightweight tank designs, materials and methods of fabrication are being investigated. These are projected to offer a 45-50 percent decrease in tank mass, representing the potential inert system mass savings. Mission and systems analyses are being conducted to guide the technology research and set priorities for technology investment, based on estimated gains in payload and mission capabilities. This includes development of advanced assessment tools and analyses of specific missions selected from Science Missions' Directorate. The goal is to mature a suite of reliable advanced propulsion technologies that will promote more cost efficient missions through the reduction of interplanetary trip time, increased scientific payload mass fraction and longer on-station operations. This talk will review the Advanced Chemical technology development roadmap, current

  18. Center for Advanced Space Propulsion

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The Center for Advanced Space Propulsion (CASP) is part of the University of Tennessee-Calspan Center for Aerospace Research (CAR). It was formed in 1985 to take advantage of the extensive research faculty and staff of the University of Tennessee and Calspan Corporation. It is also one of sixteen NASA sponsored Centers established to facilitate the Commercial Development of Space. Based on investigators' qualifications in propulsion system development, and matching industries' strong intent, the Center focused its efforts in the following technical areas: advanced chemical propulsion, electric propulsion, AI/Expert systems, fluids management in microgravity, and propulsion materials processing. This annual report focuses its discussion in these technical areas.

  19. Highlights from a Mach 4 Experimental Demonstration of Inlet Mode Transition for Turbine-Based Combined Cycle Hypersonic Propulsion

    NASA Technical Reports Server (NTRS)

    Foster, Lancert E.; Saunders, John D., Jr.; Sanders, Bobby W.; Weir, Lois J.

    2012-01-01

    NASA is focused on technologies for combined cycle, air-breathing propulsion systems to enable reusable launch systems for access to space. Turbine Based Combined Cycle (TBCC) propulsion systems offer specific impulse (Isp) improvements over rocket-based propulsion systems in the subsonic takeoff and return mission segments along with improved safety. Among the most critical TBCC enabling technologies are: 1) mode transition from the low speed propulsion system to the high speed propulsion system, 2) high Mach turbine engine development and 3) innovative turbine based combined cycle integration. To address these challenges, NASA initiated an experimental mode transition task including analytical methods to assess the state-of-the-art of propulsion system performance and design codes. One effort has been the Combined-Cycle Engine Large Scale Inlet Mode Transition Experiment (CCE-LIMX) which is a fully integrated TBCC propulsion system with flowpath sizing consistent with previous NASA and DoD proposed Hypersonic experimental flight test plans. This experiment was tested in the NASA GRC 10 by 10-Foot Supersonic Wind Tunnel (SWT) Facility. The goal of this activity is to address key hypersonic combined-cycle engine issues including: (1) dual integrated inlet operability and performance issues-unstart constraints, distortion constraints, bleed requirements, and controls, (2) mode-transition sequence elements caused by switching between the turbine and the ramjet/scramjet flowpaths (imposed variable geometry requirements), and (3) turbine engine transients (and associated time scales) during transition. Testing of the initial inlet and dynamic characterization phases were completed and smooth mode transition was demonstrated. A database focused on a Mach 4 transition speed with limited off-design elements was developed and will serve to guide future TBCC system studies and to validate higher level analyses.

  20. Continuous high order sliding mode controller design for a flexible air-breathing hypersonic vehicle.

    PubMed

    Wang, Jie; Zong, Qun; Su, Rui; Tian, Bailing

    2014-05-01

    This paper investigates the problem of tracking control with uncertainties for a flexible air-breathing hypersonic vehicle (FAHV). In order to overcome the analytical intractability of this model, an Input-Output linearization model is constructed for the purpose of feedback control design. Then, the continuous finite time convergence high order sliding mode controller is designed for the Input-Output linearization model without uncertainties. In addition, a nonlinear disturbance observer is applied to estimate the uncertainties in order to compensate the controller and disturbance suppression, where disturbance observer and controller synthesis design is obtained. Finally, the synthesis of controller and disturbance observer is used to achieve the tracking for the velocity and altitude of the FAHV and simulations are presented to illustrate the effectiveness of the control strategies. PMID:24534328

  1. Robust tracking control for an air-breathing hypersonic vehicle with input constraints

    NASA Astrophysics Data System (ADS)

    Gao, Gang; Wang, Jinzhi; Wang, Xianghua

    2014-12-01

    The focus of this paper is on the design and simulation of robust tracking control for an air-breathing hypersonic vehicle (AHV), which is affected by high nonlinearity, uncertain parameters and input constraints. The linearisation method is employed for the longitudinal AHV model about a specific trim condition, and then considering the additive uncertainties of three parameters, the linearised model is just in the form of affine parameter dependence. From this point, the linear parameter-varying method is applied to design the desired controller. The poles for the closed-loop system of the linearised model are placed into a desired vertical strip, and the quadratic stability of the closed-loop system is guaranteed. Input constraints of the AHV are addressed by additional linear matrix inequalities. Finally, the designed controller is evaluated on the nonlinear AHV model and simulation results demonstrate excellent tracking performance with good robustness.

  2. Mach 6 flow field surveys beneath the forebody of an airbreathing missile

    NASA Technical Reports Server (NTRS)

    Johnson, P. J.; Hunt, J. L.

    1986-01-01

    Wall static, local stream static, and pitot pressure surveys were made on the windward side of a hypersonic airbreathing missile at full-scale length Reynolds numbers. In the inviscid part of the flow field, the experimental massflow ratios agreed with trends predicted by a three-dimensional method-of-characteristics solution. At a longitudinal station 3.5 diameters downstrea of the nose, the boundary layer was transitional or turbulent at zero incidence but became laminar as the angle of attack increased. The bell-shaped distribution of the boundary layer across the width of the body affected the mass flow distribution out to the bow shock and decreased the mass flow available the engine inlet.

  3. Multi-Disciplinary Design Optimization of Hypersonic Air-Breathing Vehicle

    NASA Astrophysics Data System (ADS)

    Wu, Peng; Tang, Zhili; Sheng, Jianda

    2016-06-01

    A 2D hypersonic vehicle shape with an idealized scramjet is designed at a cruise regime: Mach number (Ma) = 8.0, Angle of attack (AOA) = 0 deg and altitude (H) = 30kms. Then a multi-objective design optimization of the 2D vehicle is carried out by using a Pareto Non-dominated Sorting Genetic Algorithm II (NSGA-II). In the optimization process, the flow around the air-breathing vehicle is simulated by inviscid Euler equations using FLUENT software and the combustion in the combustor is modeled by a methodology based on the well known combination effects of area-varying pipe flow and heat transfer pipe flow. Optimization results reveal tradeoffs among total pressure recovery coefficient of forebody, lift to drag ratio of vehicle, specific impulse of scramjet engine and the maximum temperature on the surface of vehicle.

  4. Planar array stack design aided by rapid prototyping in development of air-breathing PEMFC

    NASA Astrophysics Data System (ADS)

    Chen, Chen-Yu; Lai, Wei-Hsiang; Weng, Biing-Jyh; Chuang, Huey-Jan; Hsieh, Ching-Yuan; Kung, Chien-Chih

    The polymer electrolyte membrane fuel cell (PEMFC) is one of the most important research topics in the new and clean energy area. The middle or high power PEMFCs can be applied to the transportation or the distributed power system. But for the small power application, it is needed to match the power requirement of the product generally. On the other hand, the direct methanol fuel cell (DMFC) is one of the most common type that researchers are interested in, but recently the miniature or the micro-PEMFCs attract more attention due to their advantages of high open circuit voltage and high power density. The objective of this study is to develop a new air-breathing planar array fuel cell stacked from 10 cells made by rapid prototyping technology which has potential for fast commercial design, low cost manufacturing, and even without converters/inverters for the system. In this paper, the main material of flow field plates is acrylonitrile-butadiene-styrene (ABS) which allows the fuel cell be mass-manufactured by plastic injection molding technology. The rapid prototyping technology is applied to construct the prototype and verify the practicability of the proposed stack design. A 10-cell air-breathing miniature PEMFC stack with a volume of 6 cm × 6 cm × 0.9 cm is developed and tested. Its segmented membrane electrode assembly (MEA) is designed with the active surface area of 1.3 cm × 1.3 cm in each individual MEA. The platinum loading at anode and cathode are 0.2 mg cm -2 and 0.4 mg cm -2, respectively. Results show that the peak power densities of the parallel connected and serial connected stack are 99 mW cm -2 at 0.425 V and 92 mW cm -2 at 4.25 V, respectively under the conditions of 70 °C relative saturated humidity (i.e., dew point temperature), ambient temperature and free convection air. Besides, the stack performance is increased under forced convection. If the cell surface air is blown by an electric fan, the peak power densities of parallel connected and

  5. Micro electric propulsion feasibility

    NASA Technical Reports Server (NTRS)

    Aston, Graeme; Aston, Martha

    1992-01-01

    Miniature, 50 kg class, strategic satellites intended for extended deployment in space require an on-board propulsion capability to perform needed attitude control adjustments and drag compensation maneuvers. Even on such very small spacecraft, these orbit maintenance functions can be significant and result in a substantial propellant mass requirement. Development of advanced propulsion technology could reduce this propellant mass significantly, and thereby maximize the payload capability of these spacecraft. In addition, spacecraft maneuverability could be enhanced and/or multi-year mission lifetimes realized. These benefits cut spacecraft replacement costs, and reduce services needed to maintain the launch vehicles. For SDIO brilliant pebble spacecraft, a miniaturized hydrazine propulsion system provides both boost and divert thrust control. This type of propulsion system is highly integrated and is capable of delivering large thrust levels for short time periods. However, orbit maintenance functions such as drag make-up require only very small velocity corrections. Using the boost and/or divert thrusters for these small corrections exposes this highly integrated propulsion system to continuous on/off cycling and thereby increases the risk of system failure. Furthermore, since drag compensation velocity corrections would be orders of magnitude less than these thrusters were designed to deliver, their effective specific impulse would be expected to be lower when operated at very short pulse lengths. The net result of these effects would be a significant depletion of the on-board hydrazine propellant supply throughout the mission, and a reduced propulsion system reliability, both of which would degrade the interceptors usefulness. In addition to SDIO brilliant pebble spacecraft, comparably small spacecraft can be anticipated for other future strategic defense applications such as surveillance and communication. For such spacecraft, high capability and reliability

  6. State-of-the-Art for Small Satellite Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Parker, Khary I.

    2016-01-01

    The NASA/Goddard Space Flight Center (NASA/GSFC) is in the business of performing world-class, space-based, scientific research on various spacecraft platforms, which now include small satellites (SmallSats). In order to perform world class science on a SmallSat, NASA/GSFC requires that their components be highly reliable, high performing, have low power consumption, at the lowest cost possible. The Propulsion Branch (Code 597) at NASA/GSFC has conducted a SmallSat propulsion system survey to determine their availability and level of development. Based on publicly available information and unique features, this paper discusses some of the existing SmallSat propulsion systems.. The systems described in this paper do not indicate or imply any endorsement by NASA or NASA/GSFC over those not included.

  7. The Propulsion Center at MSFC

    NASA Technical Reports Server (NTRS)

    Gerrish, Harold; Schmidt, George R. (Technical Monitor)

    2000-01-01

    The Propulsion Research Center at MSFC serves as a national resource for research of advanced, revolutionary propulsion technologies. Our mission is to move the nation's capabilities beyond the confines of conventional chemical propulsion into an era of aircraft like access to earth-orbit, rapid travel throughout the solar system, and exploration of interstellar space. Current efforts cover a wide range of exciting areas, including high-energy plasma thrusters, advanced fission and fusion engines, antimatter propulsion systems, beamed energy rockets and sails, and fundamental motive physics. Activities involve concept investigation, proof-of-concept demonstration, and breadboard validation of new propulsion systems. The Propulsion Research Center at MSFC provides an environment where NASA, national laboratories, universities, and industry researchers can pool their skills together to perform landmark propulsion achievements. We offer excellent educational opportunities to students and young researchers-fostering a wellspring of innovation that will revolutionize space transportation.

  8. Electric propulsion for communications satellites

    NASA Technical Reports Server (NTRS)

    Free, B. A.; Guman, W. J.; Herron, B. G.; Zafran, S.

    1978-01-01

    Electric propulsion systems derive their low overall mass, relative to chemical propulsion systems, from an optimized mix of independently controlled power and mass flow rate. A significant reduction in mass can be secured by substituting electric propulsion for conventional hydrazine systems for all the major propulsion tasks of a communications satellite. Additional advantages for all electric propulsion maneuvers are precision location and higher pointing accuracy. Three auxiliary electric propulsion systems are now available for application on communications satellites: the electrically augmented hydrazine system, the Teflon pulsed plasma system, and the mercury ion thruster system. Primary electric propulsion will be available in the mid to late 1980s as a spin-off of NASA's program of interplanetary exploration.

  9. The NASA Electric Propulsion program

    NASA Technical Reports Server (NTRS)

    Byers, D. C.

    1984-01-01

    It is pointed out that the NASA Electric Propulsion program is aimed at providing technology for auxiliary and primary propulsion functions for earth-orbital and planetary space missions. Efforts in electrostatic propulsion include analyses of ion propulsion for Geosynchronous (GEO) and planetary spacecraft, continued preflight efforts associated with the Ion Auxiliary Propulsion System (IAPS), and research and technology for advanced and simplified ion thruster systems. In the area of electromagnetic propulsion, studies were conducted regarding the feasibility and impacts of the use of electromagnetic launchers. Research on magnetoplasmadynamic (MPD) thrusters, electromagnetic launchers, and Hall current thrusters was also performed. Studies in the electrothermal sector included an evaluation of electric propulsion options for the Space Station, taking into account also resistojets, a pulsed electrothermal thruster, and arc jets.

  10. Fusion for Space Propulsion

    NASA Technical Reports Server (NTRS)

    Thio, Y. C. Francis; Schafer, Charles (Technical Monitor)

    2001-01-01

    There is little doubt that humans will attempt to explore and develop the solar system in this century. A large amount of energy will be required for accomplishing this. The need for fusion propulsion is discussed. For a propulsion system, there are three important thermodynamical attributes: (1) The absolute amount of energy available, (2) the propellant exhaust velocity, and (3) the jet power per unit mass of the propulsion system (specific power). For human exploration and development of the solar system, propellant exhaust velocity in excess of 100 km/s and specific power in excess of 10 kW/kg are required. Chemical combustion can produce exhaust velocity up to about 5 km/s. Nuclear fission processes typically result in producing energy in the form of heat that needs to be manipulated at temperatures limited by materials to about 2,800 K. Using the energy to heat a hydrogen propellant increases the exhaust velocity by only a factor of about two. Alternatively the energy can be converted into electricity which is then used to accelerate particles to high exhaust velocity. The necessary power conversion and conditioning equipment, however, increases the mass of the propulsion system for the same jet power by more than two orders of magnitude over chemical system, thus greatly limits the thrust-to-weight ratio attainable. The principal advantage of the fission process is that its development is relatively mature and is available right now. If fusion can be developed, fusion appears to have the best of all worlds in terms of propulsion - it can provide the absolute amount, the propellant exhaust velocity, and the high specific jet power. An intermediate step towards pure fusion propulsion is a bimodal system in which a fission reactor is used to provide some of the energy to drive a fusion propulsion unit. The technical issues related to fusion for space propulsion are discussed. The technical priorities for developing and applying fusion for propulsion are

  11. STOL propulsion systems

    NASA Technical Reports Server (NTRS)

    Denington, R. J.; Koenig, R. W.; Vanco, M. R.; Sagerser, D. A.

    1972-01-01

    The selection and the characteristics of quiet, clean propulsion systems for STOL aircraft are discussed. Engines are evaluated for augmentor wing and externally blown flap STOL aircraft with the engines located both under and over the wings. Some supporting test data are presented. Optimum engines are selected based on achieving the performance, economic, acoustic, and pollution goals presently being considered for future STOL aircraft. The data and results presented were obtained from a number of contracted studies and some supporting NASA inhouse programs, most of which began in early 1972. The contracts include: (1) two aircraft and mission studies, (2) two propulsion system studies, (3) the experimental and analytic work on the augmentor wing, and (4) the experimental programs on Q-Fan. Engines are selected and discussed based on aircraft economics using the direct operating cost as the primary criterion. This cost includes the cost of the crew, fuel, aircraft, and engine maintenance and depreciation.

  12. Electromagnetic propulsion for spacecraft

    NASA Technical Reports Server (NTRS)

    Myers, Roger M.

    1993-01-01

    Three electromagnetic propulsion technologies, solid propellant pulsed plasma thrusters (PPT), magnetoplasmadynamic (MPD) thrusters, and pulsed inductive thrusters (PIT) have been developed for application to auxiliary and primary spacecraft propulsion. Both the PPT and MPD thrusters have been flown in space, though only PPTs have been used on operational satellites. The performance of operational PPTs is quite poor, providing only about 8 percent efficiency at about 1000 sec specific impulse. Laboratory PPTs yielding 34 percent efficiency at 5170 sec specific impulse have been demonstrated. Laboratory MPD thrusters have been demonstrated with up to 70 percent efficiency and 7000 sec specific impulse. Recent PIT performance measurements using ammonia and hydrazine propellants are extremely encouraging, reaching 50 percent efficiency for specific impulses between 4000 and 8000 sec.

  13. Hydrodynamics of Peristaltic Propulsion

    NASA Astrophysics Data System (ADS)

    Athanassiadis, Athanasios; Hart, Douglas

    2014-11-01

    A curious class of animals called salps live in marine environments and self-propel by ejecting vortex rings much like jellyfish and squid. However, unlike other jetting creatures that siphon and eject water from one side of their body, salps produce vortex rings by pumping water through siphons on opposite ends of their hollow cylindrical bodies. In the simplest cases, it seems like some species of salp can successfully move by contracting just two siphons connected by an elastic body. When thought of as a chain of timed contractions, salp propulsion is reminiscent of peristaltic pumping applied to marine locomotion. Inspired by salps, we investigate the hydrodynamics of peristaltic propulsion, focusing on the scaling relationships that determine flow rate, thrust production, and energy usage in a model system. We discuss possible actuation methods for a model peristaltic vehicle, considering both the material and geometrical requirements for such a system.

  14. Cryogenic Propulsion Stage

    NASA Technical Reports Server (NTRS)

    Jones, David

    2011-01-01

    The CPS is an in-space cryogenic propulsive stage based largely on state of the practice design for launch vehicle upper stages. However, unlike conventional propulsive stages, it also contains power generation and thermal control systems to limit the loss of liquid hydrogen and oxygen due to boil-off during extended in-space storage. The CPS provides the necessary (Delta)V for rapid transfer of in-space elements to their destinations or staging points (i.e., E-M L1). The CPS is designed around a block upgrade strategy to provide maximum mission/architecture flexibility. Block 1 CPS: Short duration flight times (hours), passive cryo fluid management. Block 2 CPS: Long duration flight times (days/weeks/months), active and passive cryo fluid management.

  15. Hybrid propulsion technology program

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Technology was identified which will enable application of hybrid propulsion to manned and unmanned space launch vehicles. Two design concepts are proposed. The first is a hybrid propulsion system using the classical method of regression (classical hybrid) resulting from the flow of oxidizer across a fuel grain surface. The second system uses a self-sustaining gas generator (gas generator hybrid) to produce a fuel rich exhaust that was mixed with oxidizer in a separate combustor. Both systems offer cost and reliability improvement over the existing solid rocket booster and proposed liquid boosters. The designs were evaluated using life cycle cost and reliability. The program consisted of: (1) identification and evaluation of candidate oxidizers and fuels; (2) preliminary evaluation of booster design concepts; (3) preparation of a detailed point design including life cycle costs and reliability analyses; (4) identification of those hybrid specific technologies needing improvement; and (5) preperation of a technology acquisition plan and large scale demonstration plan.

  16. Laser thermal propulsion

    NASA Technical Reports Server (NTRS)

    Keefer, D.; Elkins, R.; Peters, C.; Jones, L.

    1984-01-01

    Laser thermal propulsion (LTP) is studied for the case in which laser power is absorbed by a small very high-temperature plasma (about 20,000 K) and transferred to the remainder of the pure hydrogen propellant by radiation and mixing. This concept could lead to the realization of a lightweight orbital transfer vehicle propulsion system having a specific impulse in the range 1000-2000 s. Approximately 12 percent of the input power may be radiated to the thruster walls, and 15 percent of the total propellant flow must be heated to 20,000 K to provide a bulk temperature of 5000 K prior to expansion. Three principal research issues identified are: (1) conditions for hydrogen plasma ignition, (2) control of the plasma position within the laser beam, plasma stability, and plasma absorption efficiency, and (3) characterization of the mixing of the plasma and buffer flows.

  17. Plasmas for space propulsion

    NASA Astrophysics Data System (ADS)

    Ahedo, Eduardo

    2011-12-01

    Plasma thrusters are challenging the monopoly of chemical thrusters in space propulsion. The specific energy that can be deposited into a plasma beam is orders of magnitude larger than the specific chemical energy of known fuels. Plasma thrusters constitute a vast family of devices ranging from already commercial thrusters to incipient laboratory prototypes. Figures of merit in plasma propulsion are discussed. Plasma processes and conditions differ widely from one thruster to another, with the pre-eminence of magnetized, weakly collisional plasmas. Energy is imparted to the plasma via either energetic electron injection, biased electrodes or electromagnetic irradiation. Plasma acceleration can be electrothermal, electrostatic or electromagnetic. Plasma-wall interaction affects energy deposition and erosion of thruster elements, and thus is central for thruster efficiency and lifetime. Magnetic confinement and magnetic nozzles are present in several devices. Oscillations and turbulent transport are intrinsic to the performances of some thrusters. Several thrusters are selected in order to discuss these relevant plasma phenomena.

  18. Hypersonic missile propulsion system

    SciTech Connect

    Kazmar, R.R.

    1998-11-01

    Pratt and Whitney is developing the technology for hypersonic components and engines. A supersonic combustion ramjet (scramjet) database was developed using hydrogen fueled propulsion systems for space access vehicles and serves as a point of departure for the current development of hydrocarbon scramjets. The Air Force Hypersonic Technology (HyTech) Program has put programs in place to develop the technologies necessary to demonstrate the operability, performance and structural durability of an expendable, liquid hydrocarbon fueled scramjet system that operates from Mach 4 to 8. This program will culminate in a flight type engine test at representative flight conditions. The hypersonic technology base that will be developed and demonstrated under HyTech will establish the foundation to enable hypersonic propulsion systems for a broad range of air vehicle applications from missiles to space access vehicles. A hypersonic missile flight demonstration is planned in the DARPA Affordable Rapid Response Missile Demonstrator (ARRMD) program in 2001.

  19. Interstellar Propulsion Concepts Assessment

    NASA Technical Reports Server (NTRS)

    Forward, Robert L.

    2000-01-01

    NASA is investigating the feasibility of conducting extra-solar and interstellar missions over the next 10 to 50 years. An assessment of technologies supporting these near and far term objectives is required. To help meet these objectives the Principal Investigator assessed the feasibility of candidate propulsion systems for the proposed 'Interstellar Probe', a mission to send a spacecraft to the Heliopause at 250 AU and beyond.

  20. Emerging Propulsion Technologies

    NASA Technical Reports Server (NTRS)

    Keys, Andrew S.

    2006-01-01

    The Emerging Propulsion Technologies (EPT) investment area is the newest area within the In-Space Propulsion Technology (ISPT) Project and strives to bridge technologies in the lower Technology Readiness Level (TRL) range (2 to 3) to the mid TRL range (4 to 6). A prioritization process, the Integrated In-Space Transportation Planning (IISTP), was developed and applied in FY01 to establish initial program priorities. The EPT investment area emerged for technologies that scored well in the IISTP but had a low technical maturity level. One particular technology, the Momentum-eXchange Electrodynamic-Reboost (MXER) tether, scored extraordinarily high and had broad applicability in the IISTP. However, its technical maturity was too low for ranking alongside technologies like the ion engine or aerocapture. Thus MXER tethers assumed top priority at EPT startup in FY03 with an aggressive schedule and adequate budget. It was originally envisioned that future technologies would enter the ISP portfolio through EPT, and EPT developed an EPT/ISP Entrance Process for future candidate ISP technologies. EPT has funded the following secondary, candidate ISP technologies at a low level: ultra-lightweight solar sails, general space/near-earth tether development, electrodynamic tether development, advanced electric propulsion, and in-space mechanism development. However, the scope of the ISPT program has focused over time to more closely match SMD needs and technology advancement successes. As a result, the funding for MXER and other EPT technologies is not currently available. Consequently, the MXER tether tasks and other EPT tasks were expected to phased out by November 2006. Presentation slides are presented which provide activity overviews for the aerocapture technology and emerging propulsion technology projects.

  1. NASA propulsion controls research

    NASA Technical Reports Server (NTRS)

    Teren, F.

    1983-01-01

    Multivariable control theory is applied to the design of multiple input and output engine controls. Highly-accurate, real-time engine simulations are utilized for control development and checkout. Electro-optical control components are developed for use in electronic control systems having fiber optic data links. Integrated controls are developed for VSTOL and Rotorcraft propulsion systems. Post-stall models of engine systems are developed to aid in understanding and control of post-stall engine behavior.

  2. Free radical propulsion concept

    NASA Technical Reports Server (NTRS)

    Hawkins, C. E.; Nakanishi, S.

    1981-01-01

    The concept of a free radical propulsion system, utilizing the recombination energy of dissociated low molecular weight gases to produce thrust, is analyzed. The system, operating at a theoretical impulse with hydrogen, as high as 2200 seconds at high thrust to power ratio, is hypothesized to bridge the gap between chemical and electrostatic propulsion capabilities. A comparative methodology is outlined by which characteristics of chemical and electric propulsion for orbit raising mission can be investigated. It is noted that free radicals proposed in rockets previously met with difficulty and complexity in terms of storage requirements; the present study proposes to eliminate the storage requirements by using electric energy to achieve a continuous-flow product of free radicals which are recombined to produce a high velocity propellant. Microwave energy used to dissociate a continuously flowing gas is transferred to the propellant via three-body-recombination for conversion to propellant kinetic energy. Microwave plasma discharge was found in excess of 90 percent over a broad range of pressure in preliminary experiments, and microwave heating compared to electrothermal heating showed much higher temperatures in gasdynamic equations.

  3. The MAP Propulsion Subsystem

    NASA Technical Reports Server (NTRS)

    Davis, Gary T.; Bauer, Frank H. (Technical Monitor)

    2002-01-01

    This paper describes the requirements, design, integration, test, performance, and lessons learned of NASA's Microwave Anisotropy Probe (MAP) propulsion subsystem. MAP was launched on a Delta-II launch vehicle from NASA's Kennedy Space Center on June 30, 2001. Due to instrument thermal stability requirements, the Earth-Sun L2 Lagrange point was selected for the mission orbit. The L2 trajectory incorporated phasing loops and a lunar gravity assist. The propulsion subsystem's requirements are to manage momentum, perform maneuvers during the phasing loops to set up the lunar swingby, and perform stationkeeping at L2 for 2 years. MAP's propulsion subsystem uses 8 thrusters which are located and oriented to provide attitude control and momentum management about all axes, and delta-V in any direction without exposing the instrument to the sun. The propellant tank holds 72 kg of hydrazine, which is expelled by unregulated blowdown pressurization. Thermal management is complex because no heater cycling is allowed at L2. Several technical challenges presented themselves during I and T, such as in-situ weld repairs and in-situ bending of thruster tubes to accommodate late changes in the observatory CG. On-orbit performance has been nominal, and all phasing loop, mid-course correction, and stationkeeping maneuvers have been successfully performed to date.

  4. Geosynchronous earth orbit base propulsion - electric propulsion options

    SciTech Connect

    Palaszewski, B.

    1987-01-01

    Electric propulsion and chemical propulsion requirements for a geosynchronous earth orbit (GEO) base were analyzed. The base is resupplied from the Space Station's low earth orbit. Orbit-transfer Delta-Vs, nodal-regression Delta-Vs and orbit-maintenance Delta-Vs were considered. For resupplying the base, a cryogenic oxygen/hydrogen (O2/H2) orbital transfer vehicle (OTV) is currently-baselined. Comparisons of several electric propulsion options with the O2/H2 OTV were conducted. Propulsion requirements for missions related to the GEO base were also analyzed. Payload data for the GEO missions were drawn from current mission data bases. Detailed electric propulsion module designs are presented. Mission analyses and propulsion analyses for the GEO-delivered payloads are included. 23 references.

  5. In-Space Propulsion Solar Electric Propulsion Technology Overview

    NASA Astrophysics Data System (ADS)

    Dankanich, John W.

    2006-12-01

    NASA’s In-space Propulsion Technology Project is developing new propulsion technologies that can enable or enhance near and mid-term NASA science missions. The solar electric propulsion technology area has been investing in NASA’s Evolutionary Xenon Thruster (NEXT), the High Voltage Hall Accelerator (HiVHAC), lightweight reliable feed systems, wear testing and thruster modeling. These investments are specifically targeted to increase planetary science payload capability, expand the envelope of planetary science destinations, and significantly reduce the travel times, risk and cost of NASA planetary science missions. Current status and expected capabilities of the solar electric propulsion technologies will be discussed.

  6. NASA Breakthrough Propulsion Physics Program

    NASA Technical Reports Server (NTRS)

    Millis, Marc G.

    1998-01-01

    In 1996, NASA established the Breakthrough Propulsion Physics program to seek the ultimate breakthroughs in space transportation: propulsion that requires no propellant mass, propulsion that attains the maximum transit speeds physically possible, and breakthrough methods of energy production to power such devices. Topics of interest include experiments and theories regarding the coupling of gravity and electromagnetism, vacuum fluctuation energy, warp drives and worm-holes, and superluminal quantum effects. Because these propulsion goals are presumably far from fruition, a special emphasis is to identify affordable, near-term, and credible research that could make measurable progress toward these propulsion goals. The methods of the program and the results of the 1997 workshop are presented. This Breakthrough Propulsion Physics program, managed by Lewis Research Center, is one part of a comprehensive, long range Advanced Space Transportation Plan managed by Marshall Space Flight Center.

  7. Embedded Wing Propulsion Conceptual Study

    NASA Technical Reports Server (NTRS)

    Kim, Hyun D.; Saunders, John D.

    2003-01-01

    As a part of distributed propulsion work under NASA's Revolutionary Aeropropulsion Concepts or RAC project, a new propulsion-airframe integrated vehicle concept called Embedded Wing Propulsion (EWP) is developed and examined through system and computational fluid dynamics (CFD) studies. The idea behind the concept is to fully integrate a propulsion system within a wing structure so that the aircraft takes full benefits of coupling of wing aerodynamics and the propulsion thrust stream. The objective of this study is to assess the feasibility of the EWP concept applied to large transport aircraft such as the Blended-Wing-Body aircraft. In this paper, some of early analysis and current status of the study are presented. In addition, other current activities of distributed propulsion under the RAC project are briefly discussed.

  8. The Nuclear Cryogenic Propulsion Stage

    NASA Technical Reports Server (NTRS)

    Houts, Michael G.; Kim, Tony; Emrich, William J.; Hickman, Robert R.; Broadway, Jeramie W.; Gerrish, Harold P.; Doughty, Glen; Belvin, Anthony; Borowski, Stanley K.; Scott, John

    2014-01-01

    The fundamental capability of Nuclear Thermal Propulsion (NTP) is game changing for space exploration. A first generation Nuclear Cryogenic Propulsion Stage (NCPS) based on NTP could provide high thrust at a specific impulse above 900 s, roughly double that of state of the art chemical engines. Characteristics of fission and NTP indicate that useful first generation systems will provide a foundation for future systems with extremely high performance. The role of the NCPS in the development of advanced nuclear propulsion systems could be analogous to the role of the DC-3 in the development of advanced aviation. Progress made under the NCPS project could help enable both advanced NTP and advanced Nuclear Electric Propulsion (NEP). Nuclear propulsion can be affordable and viable compared to other propulsion systems and must overcome a biased public fear due to hyper-environmentalism and a false perception of radiation and explosion risk.

  9. Heat transfer in aerospace propulsion

    NASA Technical Reports Server (NTRS)

    Simoneau, Robert J.; Hendricks, Robert C.; Gladden, Herbert J.

    1988-01-01

    Presented is an overview of heat transfer related research in support of aerospace propulsion, particularly as seen from the perspective of the NASA Lewis Research Center. Aerospace propulsion is defined to cover the full spectrum from conventional aircraft power plants through the Aerospace Plane to space propulsion. The conventional subsonic/supersonic aircraft arena, whether commercial or military, relies on the turbine engine. A key characteristic of turbine engines is that they involve fundamentally unsteady flows which must be properly treated. Space propulsion is characterized by very demanding performance requirements which frequently push systems to their limits and demand tailored designs. The hypersonic flight propulsion systems are subject to severe heat loads and the engine and airframe are truly one entity. The impact of the special demands of each of these aerospace propulsion systems on heat transfer is explored.

  10. A membraneless air-breathing hydrogen biofuel cell based on direct wiring of thermostable enzymes on carbon nanotube electrodes.

    PubMed

    Lalaoui, Noémie; de Poulpiquet, Anne; Haddad, Raoudha; Le Goff, Alan; Holzinger, Michael; Gounel, Sébastien; Mermoux, Michel; Infossi, Pascale; Mano, Nicolas; Lojou, Elisabeth; Cosnier, Serge

    2015-05-01

    A biocathode was designed by the modification of a carbon nanotube (CNT) gas-diffusion electrode with bilirubin oxidase from Bacillus pumilus, achieving high current densities up to 3 mA cm(-2) for the reduction of O2 from air. A membraneless air-breathing hydrogen biofuel cell was designed by combination of this cathode with a functionalized CNT-based hydrogenase anode. PMID:25845356

  11. Melons are Branched Polymers

    NASA Astrophysics Data System (ADS)

    Gurau, Razvan; Ryan, James P.

    2014-11-01

    Melonic graphs constitute the family of graphs arising at leading order in the 1/N expansion of tensor models. They were shown to lead to a continuum phase, reminiscent of branched polymers. We show here that they are in fact precisely branched polymers, that is, they possess Hausdorff dimension 2 and spectral dimension 4/3.

  12. The Direction of Fluid Dynamics for Liquid Propulsion at NASA Marshall Space Flight Center

    NASA Technical Reports Server (NTRS)

    Griffin, Lisa W.

    2012-01-01

    Marshall Space Flight Center (MSFC) is the National Aeronautics and Space Administration (NASA)-designated center for the development of space launch systems. MSFC is particularly known for propulsion system development. Many engineering skills and technical disciplines are needed to accomplish this mission. This presentation will focus on the work of the Fluid Dynamics Branch (ER42). ER42 resides in the Propulsion Systems Department at MSFC. The branch is responsible for all aspects of the discipline of fluid dynamics applied to propulsion or propulsion-induced loads and environments. This work begins with design trades and parametric studies, and continues through development, risk assessment, anomaly investigation and resolution, and failure investigations. Applications include the propellant delivery system including the main propulsion system (MPS) and turbomachinery; combustion devices for liquid engines and solid rocket motors; coupled systems; and launch environments. An advantage of the branch is that it is neither analysis nor test centric, but discipline centric. Fluid dynamics assessments are made by analysis, from lumped parameter modeling through unsteady computational fluid dynamics (CFD); testing, which can be cold flow or hot fire; or a combination of analysis and testing. Integration of all discipline methods into one branch enables efficient and accurate support to the projects. To accomplish this work, the branch currently employs approximately fifty engineers divided into four teams -- Propellant Delivery CFD, Combustion Driven Flows CFD, Unsteady and Experimental Flows, and Acoustics and Stability. This discussion will highlight some of the work performed in the branch and the direction in which the branch is headed.

  13. Electrolysis Propulsion for Spacecraft Applications

    NASA Technical Reports Server (NTRS)

    deGroot, Wim A.; Arrington, Lynn A.; McElroy, James F.; Mitlitsky, Fred; Weisberg, Andrew H.; Carter, Preston H., II; Myers, Blake; Reed, Brian D.

    1997-01-01

    Electrolysis propulsion has been recognized over the last several decades as a viable option to meet many satellite and spacecraft propulsion requirements. This technology, however, was never used for in-space missions. In the same time frame, water based fuel cells have flown in a number of missions. These systems have many components similar to electrolysis propulsion systems. Recent advances in component technology include: lightweight tankage, water vapor feed electrolysis, fuel cell technology, and thrust chamber materials for propulsion. Taken together, these developments make propulsion and/or power using electrolysis/fuel cell technology very attractive as separate or integrated systems. A water electrolysis propulsion testbed was constructed and tested in a joint NASA/Hamilton Standard/Lawrence Livermore National Laboratories program to demonstrate these technology developments for propulsion. The results from these testbed experiments using a I-N thruster are presented. A concept to integrate a propulsion system and a fuel cell system into a unitized spacecraft propulsion and power system is outlined.

  14. Reactors for nuclear electric propulsion

    SciTech Connect

    Buden, D.; Angelo, J.A. Jr.

    1981-01-01

    Propulsion is the key to space exploitation and power is the key to propulsion. This paper examines the role of nuclear fission reactors as the primary power source for high specific impulse electric propulsion systems for space missions of the 1980s and 1990s. Particular mission applications include transfer to and a reusable orbital transfer vehicle from low-Earth orbit to geosynchronous orbit, outer planet exploration and reconnaissance missions, and as a versatile space tug supporting lunar resource development. Nuclear electric propulsion is examined as an indispensable component in space activities of the next two decades.

  15. Propulsion technologies for near term

    NASA Technical Reports Server (NTRS)

    Mehta, Gopal

    1991-01-01

    Propulsion system requirements and considerations; cost effective approach; booster recovery module; and commercial vehicles - evolutionary approach are outlined. This presentation is represented by viewgraphs.

  16. A comparison of chemical propulsion, nuclear thermal propulsion, and multimegawatt electric propulsion for Mars missions

    NASA Technical Reports Server (NTRS)

    Frisbee, Robert H.; Blandino, John J.; Leifer, Stephanie D.

    1991-01-01

    Various propulsion systems are considered for a split-mission piloted exploration of Mars in terms of reducing total initial mass in low earth orbit (IMLEO) as well as trip time. Aerobraked nuclear thermal propulsion (NTP), multimegawatt (MMW) nuclear electric propulsion (NEP), and MMW solar electric propulsion (SEP) are discussed and compared to a baseline aerobraked chemical propulsion system. NTP offers low IMLEO, MMW NEP allows both low IMLEO and a short trip time, and both nuclear systems offer better mission characteristics than the chemical system. The MMW SEP is concluded to be less efficient in spite of a lower IMLEO because of the system's higher specific mass and nonconstant power production. It is recommended that MMW NEP and SEP systems be considered for application to Mars cargo missions. The NEP system is concluded to be the most effective propulsion configuration for piloted Mars missions and lunar base missions.

  17. Nuclear propulsion systems engineering

    SciTech Connect

    Madsen, W.W.; Neuman, J.E.: Van Haaften, D.H.

    1992-12-31

    The Nuclear Energy for Rocket Vehicle Application (NERVA) program of the 1960`s and early 1970`s was dramatically successful, with no major failures during the entire testing program. This success was due in large part to the successful development of a systems engineering process. Systems engineering, properly implemented, involves all aspects of the system design and operation, and leads to optimization of theentire system: cost, schedule, performance, safety, reliability, function, requirements, etc. The process must be incorporated from the very first and continued to project completion. This paper will discuss major aspects of the NERVA systems engineering effort, and consider the implications for current nuclear propulsion efforts.

  18. Nuclear propulsion systems engineering

    SciTech Connect

    Madsen, W.W.; Neuman, J.E.: Van Haaften, D.H.

    1992-01-01

    The Nuclear Energy for Rocket Vehicle Application (NERVA) program of the 1960's and early 1970's was dramatically successful, with no major failures during the entire testing program. This success was due in large part to the successful development of a systems engineering process. Systems engineering, properly implemented, involves all aspects of the system design and operation, and leads to optimization of theentire system: cost, schedule, performance, safety, reliability, function, requirements, etc. The process must be incorporated from the very first and continued to project completion. This paper will discuss major aspects of the NERVA systems engineering effort, and consider the implications for current nuclear propulsion efforts.

  19. Miniature propulsion systems

    NASA Astrophysics Data System (ADS)

    Campbell, John G.

    1992-07-01

    Miniature solenoid valves, check valves and a hydrazine gas generator typify the miniaturization used in the liquid propulsion system for the Army Light Weight Exo-Atmospheric Projectile (LEAP). The pressure control subsystem uses a solenoid valve weighing 24 grams to control flow of helium to pressurize the propellant tanks. The attitude control subsystem uses a gas generator weighing 71 grams to produce decomposed hydrazine as the gaseous propellant for miniature 1 lbf ACS thrusters weighing 5.4 grams. The successful use of these miniature components in development tests and a hover test of the LEAP is described.

  20. Electromagnetic propulsion test facility

    NASA Technical Reports Server (NTRS)

    Gooder, S. T.

    1984-01-01

    A test facility for the exploration of electromagnetic propulsion concept is described. The facility is designed to accommodate electromagnetic rail accelerators of various lengths (1 to 10 meters) and to provide accelerating energies of up to 240 kiloJoules. This accelerating energy is supplied as a current pulse of hundreds of kiloAmps lasting as long as 1 millisecond. The design, installation, and operating characteristics of the pulsed energy system are discussed. The test chamber and its operation at pressures down to 1300 Pascals (10 mm of mercury) are described. Some aspects of safety (interlocking, personnel protection, and operating procedures) are included.

  1. Advanced propulsion concepts

    NASA Technical Reports Server (NTRS)

    Sercel, Joel C.

    1991-01-01

    The topics presented are covered in viewgraph form. The programmatic objective is to establish the feasibility of propulsion technologies for vastly expanded space activity. The technical objective is a revolutionary performance sought, such as: (1) about 1 kg/kW specific mass; (2) specific impulse tailored to mission requirements; (3) ability to use in-situ resources; (4) round-trips to Mars in months; (5) round-trips to outer planets in 1 to 2 years; and (6) the capability for robotic mission beyond the solar system.

  2. Investigation of advanced propulsion technologies: The RAM accelerator and the flowing gas radiation heater

    NASA Technical Reports Server (NTRS)

    Bruckner, A. P.; Knowlen, C.; Mattick, A. T.; Hertzberg, A.

    1992-01-01

    The two principal areas of advanced propulsion investigated are the ram accelerator and the flowing gas radiation heater. The concept of the ram accelerator is presented as a hypervelocity launcher for large-scale aeroballistic range applications in hypersonics and aerothermodynamics research. The ram accelerator is an in-bore ramjet device in which a projectile shaped like the centerbody of a supersonic ramjet is propelled in a stationary tube filled with a tailored combustible gas mixture. Combustion on and behind the projectile generates thrust which accelerates it to very high velocities. The acceleration can be tailored for the 'soft launch' of instrumented models. The distinctive reacting flow phenomena that have been observed in the ram accelerator are relevant to the aerothermodynamic processes in airbreathing hypersonic propulsion systems and are useful for validating sophisticated CFD codes. The recently demonstrated scalability of the device and the ability to control the rate of acceleration offer unique opportunities for the use of the ram accelerator as a large-scale hypersonic ground test facility. The flowing gas radiation receiver is a novel concept for using solar energy to heat a working fluid for space power or propulsion. Focused solar radiation is absorbed directly in a working gas, rather than by heat transfer through a solid surface. Previous theoretical analysis had demonstrated that radiation trapping reduces energy loss compared to that of blackbody receivers, and enables higher efficiencies and higher peak temperatures. An experiment was carried out to measure the temperature profile of an infrared-active gas and demonstrate the effect of radiation trapping. The success of this effort validates analytical models of heat transfer in this receiver, and confirms the potential of this approach for achieving high efficiency space power and propulsion.

  3. Influence of cathode opening size and wetting properties of diffusion layers on the performance of air-breathing PEMFCs

    NASA Astrophysics Data System (ADS)

    Schmitz, A.; Tranitz, M.; Eccarius, S.; Weil, A.; Hebling, C.

    Air-breathing PEMFCs consist of an open cathodic side to allow an entirely passive supply of oxygen by diffusion. Furthermore, a large fraction of the produced water is removed by evaporation from the open cathode. Gas diffusion layers (GDLs) and the opening size of the cathode have a crucial influence on the performance of an air-breathing PEMFC. In order to assure an unobstructed supply of oxygen the water has to be removed efficiently and condensation in the GDL has to be avoided. On the other hand good humidification of the membrane has to be achieved to obtain high protonic conductivity. In this paper the influence of varying cathodic opening sizes (33%, 50% and 80% opening ratios) and of GDLs with different wetting properties are analysed. GDLs with hydrophobic and hydrophilic properties are prepared by coating of untreated GDLs (Toray ® carbon paper TGP-H-120, thickness of 350 μm). The air-breathing PEMFC test samples are realised using printed circuit board (PCB) technology. The cell samples were characterised over the entire potential range (0-0.95 V) by extensive measurements of the current density, the temperature and the cell impedance at 1 kHz. Additionally, measurements of the water balance were carried out at distinct operation points. The best cell performance was achieved with the largest opening ratio (80%) and an untreated GDL. At the maximum power point, this cell sample achieved a power density of 100 mW cm -2 at a moderate cell temperature of 43 °C. Furthermore, it could be shown that GDLs with hydrophilic or intense hydrophobic properties do not improve the performance of an air-breathing PEMFC. Based on the extensive characterisations, two design rules for air-breathing PEMFCs could be formulated. Firstly, it is crucial to maximise the cathode opening as far as an appropriate compression pressure of the cell assembly and therewith low contact resistance can be assured. Secondly, it is advantageous to use an untreated, slightly hydrophobic

  4. Additive Manufacturing of Aerospace Propulsion Components

    NASA Technical Reports Server (NTRS)

    Misra, Ajay K.; Grady, Joseph E.; Carter, Robert

    2015-01-01

    The presentation will provide an overview of ongoing activities on additive manufacturing of aerospace propulsion components, which included rocket propulsion and gas turbine engines. Future opportunities on additive manufacturing of hybrid electric propulsion components will be discussed.

  5. Space propulsion technology and cryogenic fluid depot

    NASA Technical Reports Server (NTRS)

    Diehl, Larry A.

    1988-01-01

    Information on space propulsion and technology and the cryogenic fluid depot is given in viewgraph form. Information is given on orbit transfer, electric propulsion, spacecraft propulsion, and program objectives.

  6. Hybrid propulsion systems for space exploration missions

    NASA Technical Reports Server (NTRS)

    Darooka, D. K.

    1991-01-01

    Combinations of nuclear thermal propulsion (NTP), nuclear electric propulsion (NEP), and chemical propulsion are discussed. Technical details are given in viewgraph form. The characteristics of each configuration are discussed, particularly thrust characteristics.

  7. Materials Test Branch

    NASA Technical Reports Server (NTRS)

    Gordon, Gail

    2012-01-01

    The Materials Test Branch resides at Marshall Space Flight Center's Materials and Processing laboratory and has a long history of supporting NASA programs from Mercury to the recently retired Space Shuttle. The Materials Test Branch supports its customers by supplying materials testing expertise in a wide range of applications. The Materials Test Branch is divided into three Teams, The Chemistry Team, The Tribology Team and the Mechanical Test Team. Our mission and goal is to provide world-class engineering excellence in materials testing with a special emphasis on customer service.

  8. Assessing Potential Propulsion Breakthroughs

    NASA Technical Reports Server (NTRS)

    Millis, Marc G.

    2005-01-01

    The term, propulsion breakthrough, refers to concepts like propellantless space drives and faster-than-light travel, the kind of breakthroughs that would make interstellar exploration practical. Although no such breakthroughs appear imminent, a variety of investigations into these goals have begun. From 1996 to 2002, NASA supported the Breakthrough Propulsion Physics Project to examine physics in the context of breakthrough spaceflight. Three facets of these assessments are now reported: (1) predicting benefits, (2) selecting research, and (3) recent technical progress. Predicting benefits is challenging since the breakthroughs are still only notional concepts, but kinetic energy can serve as a basis for comparison. In terms of kinetic energy, a hypothetical space drive could require many orders of magnitude less energy than a rocket for journeys to our nearest neighboring star. Assessing research options is challenging when the goals are beyond known physics and when the implications of success are profound. To mitigate the challenges, a selection process is described where: (a) research tasks are constrained to only address the immediate unknowns, curious effects or critical issues, (b) reliability of assertions is more important than their implications, and (c) reviewers judge credibility rather than feasibility. The recent findings of a number of tasks, some selected using this process, are discussed. Of the 14 tasks included, six reached null conclusions, four remain unresolved, and four have opportunities for sequels. A dominant theme with the sequels is research about the properties of space, inertial frames, and the quantum vacuum.

  9. Electromagnetic propulsion for spacecraft

    NASA Astrophysics Data System (ADS)

    Myers, Roger M.

    1993-09-01

    Three electromagnetic propulsion technologies, solid propellant pulsed plasma thrusters (PPT), magnetoplasmadynamic (MPD) thrusters, and pulsed inductive thrusters (PIT), were developed for application to auxiliary and primary spacecraft propulsion. Both the PPT and MPD thrusters were flown in space, though only PPT's were used on operational satellites. The performance of operational PPT's is quite poor, providing only approximately 8 percent efficiency at approximately 1000 s specific impulse. However, laboratory PPT's yielding 34 percent efficiency at 2000 s specific impulse were extensively tested, and peak performance levels of 53 percent efficiency at 5170 s specific impulse were demonstrated. MPD thrusters were flown as experiments on the Japanese MS-T4 spacecraft and the Space Shuttle and were qualified for a flight in 1994. The flight MPD thrusters were pulsed, with a peak performance of 22 percent efficiency at 2500 s specific impulse using ammonia propellant. Laboratory MPD thrusters were demonstrated with up to 70 percent efficiency and 700 s specific impulse using lithium propellant. While the PIT thruster has never been flown, recent performance measurements using ammonia and hydrazine propellants are extremely encouraging, reaching 50 percent efficiency for specific impulses between 4000 to 8000 s. The fundamental operating principles, performance measurements, and system level design for the three types of electromagnetic thrusters are reviewed, and available data on flight tests are discussed for the PPT and MPD thrusters.

  10. Electromagnetic propulsion for spacecraft

    NASA Technical Reports Server (NTRS)

    Myers, Roger M.

    1993-01-01

    Three electromagnetic propulsion technologies, solid propellant pulsed plasma thrusters (PPT), magnetoplasmadynamic (MPD) thrusters, and pulsed inductive thrusters (PIT), were developed for application to auxiliary and primary spacecraft propulsion. Both the PPT and MPD thrusters were flown in space, though only PPT's were used on operational satellites. The performance of operational PPT's is quite poor, providing only approximately 8 percent efficiency at approximately 1000 s specific impulse. However, laboratory PPT's yielding 34 percent efficiency at 2000 s specific impulse were extensively tested, and peak performance levels of 53 percent efficiency at 5170 s specific impulse were demonstrated. MPD thrusters were flown as experiments on the Japanese MS-T4 spacecraft and the Space Shuttle and were qualified for a flight in 1994. The flight MPD thrusters were pulsed, with a peak performance of 22 percent efficiency at 2500 s specific impulse using ammonia propellant. Laboratory MPD thrusters were demonstrated with up to 70 percent efficiency and 700 s specific impulse using lithium propellant. While the PIT thruster has never been flown, recent performance measurements using ammonia and hydrazine propellants are extremely encouraging, reaching 50 percent efficiency for specific impulses between 4000 to 8000 s. The fundamental operating principles, performance measurements, and system level design for the three types of electromagnetic thrusters are reviewed, and available data on flight tests are discussed for the PPT and MPD thrusters.

  11. Quality Issues in Propulsion

    NASA Technical Reports Server (NTRS)

    McCarty, John P.; Lyles, Garry M.

    1997-01-01

    Propulsion system quality is defined in this paper as having high reliability, that is, quality is a high probability of within-tolerance performance or operation. Since failures are out-of-tolerance performance, the probability of failures and their occurrence is the difference between high and low quality systems. Failures can be described at 3 levels: the system failure (which is the detectable end of a failure), the failure mode (which is the failure process), and the failure cause (which is the start). Failure causes can be evaluated & classified by type. The results of typing flight history failures shows that most failures are in unrecognized modes and result from human error or noise, i.e. failures are when engineers learn how things really work. Although the study based on US launch vehicles, a sampling of failures from other countries indicates the finding has broad application. The parameters of the design of a propulsion system are not single valued, but have dispersions associated with the manufacturing of parts. Many tests are needed to find failures, if the dispersions are large relative to tolerances, which could contribute to the large number of failures in unrecognized modes.

  12. Integrated airframe propulsion control

    NASA Technical Reports Server (NTRS)

    Fennell, R. E.; Black, S. B.

    1982-01-01

    Perturbation equations which describe flight dynamics and engine operation about a given operating point are combined to form an integrated aircraft/propulsion system model. Included in the model are the dependence of aerodynamic coefficients upon atmospheric variables along with the dependence of engine variables upon flight condition and inlet performance. An off-design engine performance model is used to identify interaction parameters in the model. Inclusion of subsystem interaction effects introduces coupling between flight and propulsion variables. To analyze interaction effects on control, consideration is first given to control requirements for separate flight and engine models. For the separate airframe model, feedback control provides substantial improvement in short period damping. For the integrated system, feedback control compensates for the coupling present in the model and provides good overall system stability. However, this feedback control law involves many non-zero gains. Analysis of suboptimal control strategies indicates that performance of the closed loop integrated system can be maintained with a feedback matrix in which the number of non-zero gains is small relative to the number of components in the feedback matrix.

  13. Emergent Propulsion Systems

    NASA Astrophysics Data System (ADS)

    El-Fakdi Sencianes, Andres

    2002-01-01

    almost an Engineer (2002 will be my last year as student) and the studies that I'm now ending here, in Girona, are closely related not only with science and technology subjects but with optimization and economic result obtention, too. Huge distances that separate us from everything in space have launched scientists and engineers into a new challenge: How to reach maximum speeds keeping high ratios payload/total spacecraft mass? The key limitation of chemical rockets is that their exhaust velocity is relatively low. Because achieving Earth orbit requires a high velocity change a rocket must carry far more propellant than payload. The answer to all this complications seems to stare in one way: electric propulsion systems and the possibility of taking advantatge of solar winds to thrust our crafts. possible solutions, some of them have been studied for years and now they are not a project but a reality; also newest theories bring us the possibility of dream. Improve of commom propellants, search of new ones: Investigators continued research on use of atomic species as high-energy-density propellants, which could increase the specific impulse of hydrogen/oxygen rockets by 50-150%. Nuclear fission propulsion: Centered in development of reactors for nearterm nuclear electric propulsion aplications. Multimegawatt systems based on vapor core reactors and magnetohydrodynamic power conversion. Engineers investigated new fuels for compact nuclear thermal propulsion systems. What is called plasma state?: When a gas is heated to tens of thousands or millions of degrees, atoms lose their electrons. The result is a "soup" of charged particles, or plasma, made up of negatively charged electrons and positively charged ions. No known material can contain the hot plasma necessary for rocket propulsion, but specially designed magnetic fields can. Plasma rockets: This rockets are not powered by conventional chemical reactions as today's rockets are, but by electrical energy that heats

  14. Nuclear electric propulsion systems overview

    NASA Technical Reports Server (NTRS)

    Doherty, Michael P.

    1993-01-01

    The topics are presented in viewgraph form and include the following: nuclear propulsion background; schedule for the nuclear electric propulsion (NEP) project; NEP for the Space Exploration Initiative; NEP on-going systems tasks; 20KWe mission/system study; and agenda.

  15. Progress in NASA Rotorcraft Propulsion

    NASA Technical Reports Server (NTRS)

    DellaCorte, Christopher; Johnson, Susan M.

    2008-01-01

    This presentation reviews recent progress made under NASA s Subsonic Rotary Wing (SRW) propulsion research activities. Advances in engines, drive systems and optimized propulsion systems are discussed. Progress in wide operability compressors, modeling of variable geometry turbine performance, foil gas bearings and multi-speed transmissions are presented.

  16. Exotic power and propulsion concepts

    NASA Technical Reports Server (NTRS)

    Forward, Robert L.

    1990-01-01

    The status of some exotic physical phenomena and unconventional spacecraft concepts that might produce breakthroughs in power and propulsion in the 21st Century are reviewed. The subjects covered include: electric, nuclear fission, nuclear fusion, antimatter, high energy density materials, metallic hydrogen, laser thermal, solar thermal, solar sail, magnetic sail, and tether propulsion.

  17. Nuclear propulsion for space exploration

    NASA Technical Reports Server (NTRS)

    Miller, Thomas J.; Bennett, Gary L.

    1992-01-01

    The results of some recent studies of the application of both nuclear electric and nuclear thermal propulsion systems in space exploration are presented. Issues that require further study and which have a significant effect on the propulsion system design and selection are identified. Attention is given to robotic missions, lunar piloted and cargo missions, and Mars missions.

  18. The NASA Electric Propulsion Program

    NASA Technical Reports Server (NTRS)

    Byers, David C.; Wasel, Robert A.

    1987-01-01

    The NASA OAST Propulsion, Power and Energy Division supports electric propulsion for a broad class of missions. Concepts with potential to significantly benefit or enable space exploration and exploitation are identified and advanced toward applications in the near to far term. Recent program progress in mission/system analyses and in electrothermal, ion, and electromagnetic technologies are summarized.

  19. A Status Report of the X-50LR Program: A Laser Propulsion Program

    NASA Astrophysics Data System (ADS)

    Mead, Frank B., Jr.; Larson, C. W.; Kalliomaa, Wayne M.

    2001-10-01

    In 1996, the Air Force Research Lab's Propulsion Division at Edwards AFB initiated a program that had as its main objective to launch a laser-propelled vehicle into a suborbital trajectory within a period of 5 years in order to demonstrate the concept and its attractive features. The concept was to be a nanosatellite in which the laser propulsion engine and satellite hardware were intimately shared. This concept was based upon a 1989 design developed at Rensselaer Polytechnic Institute under a Space Defense Initiative Office laser propulsion program. The forebody aeroshell had been designed to act as an external compression surface (i.e. the airbreathing engine inlet). The afterbody served a dual function as a primary receptive optic (parabolic mirror) for the laser beam and as an external expansion surface (plug nozzle). The primary thrust structure was the centrally located annular shroud. The shroud provided air through inlets and acts as a energy absorption chamber for plasma formation. In the rocket mode, the air inlets were closed, and the afterbody and shroud combined to form the rocket thrust chamber and plug ('aerospike-type') nozzle. The fully-scale vehicle was 1.4 meters in diameter with a dry mass of 120 kg. Fully fueled, this vehicle would have an initial mass of about 240 kg (i.e., a mass fraction of 0.5), and would be launched into orbit with a 100 megawatt-class infrared ground-based laser (GBL). This laser propelled vehicle would be a single-stage-to-orbit (i.e., airbreathing only to M=5 and 30 km; a laser thermal rocket, using liquid propellants, at higher altitudes and in space) using a combined-cycle pulsed detonation engine. Once in space, the Lightcraft was to use its one meter diameter optical system to provide, for example, Earth surveys from low Earth orbit with 8-15 cm resolution in the visible light frequencies. Such a device was simple, reliable, safe, environmentally clean, and could have a very high all azimuth on demand launch rate.

  20. The NASA Electric Propulsion Program

    NASA Technical Reports Server (NTRS)

    Callahan, Lisa Wood; Curran, Francis M.

    1996-01-01

    Nearly all space missions require on-board propulsion systems and these systems typically have a major impact on spacecraft mass and cost. Electric propulsion systems offer major performance advantages over conventional chemical systems for many mission functions and the NASA Office of Space Access and Technology (OSAT) supports an extensive effort to develop the technology for high-performance, on-board electric propulsion system options to enhance and enable near- and far-term US space missions. This program includes research and development efforts on electrothermal, electrostatic, and electromagnetic propulsion system technologies to cover a wide range of potential applications. To maximize expectations of technology transfer, the program emphasizes strong interaction with the user community through a variety of cooperative and contracted approaches. This paper provides an overview of the OSAT electric propulsion program with an emphasis on recent progress and future directions.

  1. Air-breathing direct formic acid microfluidic fuel cell with an array of cylinder anodes

    NASA Astrophysics Data System (ADS)

    Zhu, Xun; Zhang, Biao; Ye, Ding-Ding; Li, Jun; Liao, Qiang

    2014-02-01

    An air-breathing direct formic acid membraneless microfluidic fuel cell using graphite cylinder arrays as the anode is proposed. The three dimensional anode volumetrically extends the reactive surface area and improves fuel utilization. The effects of spacer configuration, fuel and electrolyte concentration as well as reactant flow rate on the species transport and cell performance are investigated. The dynamic behavior of generated CO2 bubbles is visualized and its effect on current generation is discussed. The results show that the absence of two spacers adjacent to the cathode surface improves the cell performance by reducing the proton transfer resistance. The CO2 gas bubbles are constrained within the anode array and expelled by the fluid flow periodically. Proper reactant concentration and flow rate are crucial for cell operation. At optimum conditions, a maximum current density of 118.3 mA cm-3 and a peak power density of 21.5 mW cm-3 are obtained. In addition, benefit from the volumetrically stacked anodes and enhanced fuel transfer, the maximum single pass fuel utilization rate reaches up to 87.6% at the flow rate of 1 mL h-1.

  2. Computational modeling of alkaline air-breathing microfluidic fuel cells with an array of cylinder anodes

    NASA Astrophysics Data System (ADS)

    Ye, Ding-Ding; Zhang, Biao; Zhu, Xun; Sui, Pang-Chieh; Djilali, Ned; Liao, Qiang

    2015-08-01

    A three-dimensional computational model is developed for an alkaline air-breathing microfluidic fuel cell (AMFC) with an array of cylinder anodes. The model is validated against experimental data from an in-house prototype AMFC. The distributions of fluid velocity, fuel concentration and current density of the fuel cell are analyzed in detail. The effect of reactant flow rate on the cell performance and electrode potentials is also studied. The model results suggest that fuel crossover is minimized by the fast electrolyte flow in the vicinity of the cathode. The current production of each anode is uneven and is well correlated with internal ohmic resistance. Fuel transfer limitation occurs at low flow rates (<100 μL min-1) but diminishes at high flow rates. The model results also indicate that cathode potential reversal takes place at combined low flow rate and high current density conditions, mainly due to the improved overpotential downstream where fuel starvation occurs. The anode reaction current distribution is found to be relatively uniform, which is a result of a compensating mechanism that improves the current production of the bottom anodes downstream.

  3. Uncertainty analysis and robust trajectory linearization control of a flexible air-breathing hypersonic vehicle

    NASA Astrophysics Data System (ADS)

    Pu, Zhiqiang; Tan, Xiangmin; Fan, Guoliang; Yi, Jianqiang

    2014-08-01

    Flexible air-breathing hypersonic vehicles feature significant uncertainties which pose huge challenges to robust controller designs. In this paper, four major categories of uncertainties are analyzed, that is, uncertainties associated with flexible effects, aerodynamic parameter variations, external environmental disturbances, and control-oriented modeling errors. A uniform nonlinear uncertainty model is explored for the first three uncertainties which lumps all uncertainties together and consequently is beneficial for controller synthesis. The fourth uncertainty is additionally considered in stability analysis. Based on these analyses, the starting point of the control design is to decompose the vehicle dynamics into five functional subsystems. Then a robust trajectory linearization control (TLC) scheme consisting of five robust subsystem controllers is proposed. In each subsystem controller, TLC is combined with the extended state observer (ESO) technique for uncertainty compensation. The stability of the overall closed-loop system with the four aforementioned uncertainties and additional singular perturbations is analyzed. Particularly, the stability of nonlinear ESO is also discussed from a Liénard system perspective. At last, simulations demonstrate the great control performance and the uncertainty rejection ability of the robust scheme.

  4. Migration history of air-breathing fishes reveals Neogene atmospheric circulation patterns

    NASA Astrophysics Data System (ADS)

    Böhme, M.

    2004-05-01

    The migration history of an air-breathing fish group (Channidae; snakehead fishes) is used for reconstructing Neogene Eurasian precipitation and atmospheric circulation patterns. The study shows that snakeheads are sensitive indicators of summer precipitation maxima in subtropical and temperate regions, and are present regularly if the wettest month exceeds 150 mm precipitation and 20 °C mean temperature. The analysis of 515 fossil freshwater fish deposits of the past 50 m.y. from Africa and Eurasia shows two continental-scale migration events from the snakeheads' center of origin in the south Himalayan region, events that can be related to changes in the Northern Hemisphere circulation pattern. The first migration, ca. 17.5 Ma, into western and central Eurasia may have been caused by a northward shift of the Intertropical Convergence Zone that brought western Eurasia under the influence of trade winds that produced a zonal and meridional precipitation gradient in Europe. During the second migration, between 8 and 4 Ma, into Africa and East Asia, snakeheads reached their present-day distribution. This migration could have been related to the intensification of the Asian monsoon that brought summer precipitation to their migratory pathways in East Africa Arabia and East Asia.

  5. Navier-Stokes predictions of dynamic stability derivatives for air-breathing hypersonic vehicle

    NASA Astrophysics Data System (ADS)

    Liu, Xu; Liu, Wei; Zhao, Yunfei

    2016-01-01

    Dynamic derivatives are important parameters for designing vehicle trajectory and attitude control system that directly decide the divergence behavior of vibration of the aircraft open-loop system under interference. After calibration model validation, the dynamic behavior of air-breathing hypersonic vehicle WR-A is characterized. The unsteady flow field of aircraft forced simple harmonic vibration (SHV) is simulated using N-S equation. The direct damping derivatives, cross derivatives, acceleration derivatives and rotary derivatives of WR-A under different frequencies, amplitudes and positions of centroid are obtained. Research demonstrates that the proportion of acceleration derivatives, which represents the flow time lag effect, in the direct damping derivatives can be as high as 40% but is opposite to the damping derivative value symbols in some cases, contributing to dynamic instability. Numerical simulation on large-amplitude forced vibration of WR-A indicates that the aerodynamic behavior predicted by the dynamic derivative model agrees well with unsteady calculations. The inlet performance parameter derivatives are solved using the Etkin theory. The inlet performance parameters under large-amplitude vibration are successfully predicted using the dynamic derivative model. This offers a guideline for characterizing the dynamic internal flow field and unsteady inlet performance.

  6. Design Evolution and Performance Characterization of the GTX Air-Breathing Launch Vehicle Inlet

    NASA Technical Reports Server (NTRS)

    DeBonis, J. R.; Steffen, C. J., Jr.; Rice, T.; Trefny, C. J.

    2002-01-01

    The design and analysis of a second version of the inlet for the GTX rocket-based combine-cycle launch vehicle is discussed. The previous design did not achieve its predicted performance levels due to excessive turning of low-momentum comer flows and local over-contraction due to asymmetric end-walls. This design attempts to remove these problems by reducing the spike half-angle to 10- from 12-degrees and by implementing true plane of symmetry end-walls. Axisymmetric Reynolds-Averaged Navier-Stokes simulations using both perfect gas and real gas, finite rate chemistry, assumptions were performed to aid in the design process and to create a comprehensive database of inlet performance. The inlet design, which operates over the entire air-breathing Mach number range from 0 to 12, and the performance database are presented. The performance database, for use in cycle analysis, includes predictions of mass capture, pressure recovery, throat Mach number, drag force, and heat load, for the entire Mach range. Results of the computations are compared with experimental data to validate the performance database.

  7. Correlation and analysis of oil flow data for an air-breathing missile model

    NASA Technical Reports Server (NTRS)

    Stoy, S. L.; Dillon, J. L.; Roman, A. P.

    1985-01-01

    This paper will present the results of an oil flow investigation on an airbreathing missile model. This oil flow study examined the flow around the model, which can be configured with both axisymmetric and two-dimensional inlets. Flow visualization analyses were conducted for both types of geometries by examining the surface flow patterns made visible by the oil flows for Mach numbers of 2.5 and 3.95. The analysis has shown the extent of flow spillage around the inlet which has helped explain the force and moment data collected during previous testing of the model. The oil flow data has also been used to develop guidelines for modeling the location of the crossflow separation line along inlet fairings. Finally, the oil flow analysis has been used to identify unique features of the boattail flow. These boattail flow characteristics have been correlated with previous oil flow analysis of noncircular body models. This paper demonstrates the use of this type of oil flow analysis in developing missile flow field analysis and aerodynamic predictions ranging from impact angle methods through Navier-Stokes methods.

  8. The Olive Branch Awards.

    ERIC Educational Resources Information Center

    Harnack, William

    1984-01-01

    The first annual Olive Branch Awards, sponsored by the Writers' and Publishers Alliance and the Editors' Organizing Committee, were given to ten magazines, out of 60 that submitted entries. Winning entries are described briefly. (IM)

  9. Overview of Glenn Mechanical Components Branch Research

    NASA Astrophysics Data System (ADS)

    Zakrajsek, James

    2002-09-01

    Mr. James Zakrajsek, chief of the Mechanical Components Branch, gave an overview of research conducted by the branch. Branch members perform basic research on mechanical components and systems, including gears and bearings, turbine seals, structural and thermal barrier seals, and space mechanisms. The research is focused on propulsion systems for present and advanced aerospace vehicles. For rotorcraft and conventional aircraft, we conduct research to develop technology needed to enable the design of low noise, ultra safe geared drive systems. We develop and validate analytical models for gear crack propagation, gear dynamics and noise, gear diagnostics, bearing dynamics, and thermal analyses of gear systems using experimental data from various component test rigs. In seal research we develop and test advanced turbine seal concepts to increase efficiency and durability of turbine engines. We perform experimental and analytical research to develop advanced thermal barrier seals and structural seals for current and next generation space vehicles. Our space mechanisms research involves fundamental investigation of lubricants, materials, components and mechanisms for deep space and planetary environments.

  10. Overview of Glenn Mechanical Components Branch Research

    NASA Technical Reports Server (NTRS)

    Zakrajsek, James

    2002-01-01

    Mr. James Zakrajsek, chief of the Mechanical Components Branch, gave an overview of research conducted by the branch. Branch members perform basic research on mechanical components and systems, including gears and bearings, turbine seals, structural and thermal barrier seals, and space mechanisms. The research is focused on propulsion systems for present and advanced aerospace vehicles. For rotorcraft and conventional aircraft, we conduct research to develop technology needed to enable the design of low noise, ultra safe geared drive systems. We develop and validate analytical models for gear crack propagation, gear dynamics and noise, gear diagnostics, bearing dynamics, and thermal analyses of gear systems using experimental data from various component test rigs. In seal research we develop and test advanced turbine seal concepts to increase efficiency and durability of turbine engines. We perform experimental and analytical research to develop advanced thermal barrier seals and structural seals for current and next generation space vehicles. Our space mechanisms research involves fundamental investigation of lubricants, materials, components and mechanisms for deep space and planetary environments.

  11. Branch retinal vein occlusion.

    PubMed

    Hamid, Sadaf; Mirza, Sajid Ali; Shokh, Ishrat

    2008-01-01

    Retinal vein occlusions (RVO) are the second commonest sight threatening vascular disorder. Branch retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO) are the two basic types of vein occlusion. Branch retinal vein occlusion is three times more common than central retinal vein occlusion and- second only to diabetic retinopathy as the most common retinal vascular cause of visual loss. The origin of branch retinal vein occlusion undoubtedly includes both systemic factors such as hypertension and local anatomic factors such as arteriovenous crossings. Branch retinal vein occlusion causes a painless decrease in vision, resulting in misty or distorted vision. Current treatment options don't address the underlying aetiology of branch retinal vein occlusion. Instead they focus on treating sequelae of the occluded venous branch, such as macular oedema, vitreous haemorrhage and traction retinal detachment from neovascularization. Evidences suggest that the pathogenesis of various types of retinal vein occlusion, like many other ocular vascular occlusive disorders, is a multifactorial process and there is no single magic bullet that causes retinal vein occlusion. A comprehensive management of patients with retinal vascular occlusions is necessary to correct associated diseases or predisposing abnormalities that could lead to local recurrences or systemic event. Along with a review of the literature, a practical approach for the management of retinal vascular occlusions is required, which requires collaboration between the ophthalmologist and other physicians: general practitioner, cardiologist, internist etc. as appropriate according to each case. PMID:19385476

  12. Developmental transcriptome analysis and identification of genes involved in formation of intestinal air-breathing function of Dojo loach, Misgurnus anguillicaudatus.

    PubMed

    Luo, Weiwei; Cao, Xiaojuan; Xu, Xiuwen; Huang, Songqian; Liu, Chuanshu; Tomljanovic, Tea

    2016-01-01

    Dojo loach, Misgurnus anguillicaudatus is a freshwater fish species of the loach family Cobitidae, using its posterior intestine as an accessory air-breathing organ. Little is known about the molecular regulatory mechanisms in the formation of intestinal air-breathing function of M. anguillicaudatus. Here high-throughput sequencing of mRNAs was performed from six developmental stages of posterior intestine of M. anguillicaudatus: 4-Dph (days post hatch) group, 8-Dph group, 12-Dph group, 20-Dph group, 40-Dph group and Oyd (one-year-old) group. These six libraries were assembled into 81300 unigenes. Totally 40757 unigenes were annotated. Subsequently, 35291 differentially expressed genes (DEGs) were scanned among different developmental stages and clustered into 20 gene expression profiles. Finally, 15 key pathways and 25 key genes were mined, providing potential targets for candidate gene selection involved in formation of intestinal air-breathing function in M. anguillicaudatus. This is the first report of developmental transcriptome of posterior intestine in M. anguillicaudatus, offering a substantial contribution to the sequence resources for this species and providing a deep insight into the formation mechanism of its intestinal air-breathing function. This report demonstrates that M. anguillicaudatus is a good model for studies to identify and characterize the molecular basis of accessory air-breathing organ development in fish. PMID:27545457

  13. Developmental transcriptome analysis and identification of genes involved in formation of intestinal air-breathing function of Dojo loach, Misgurnus anguillicaudatus

    PubMed Central

    Luo, Weiwei; Cao, Xiaojuan; Xu, Xiuwen; Huang, Songqian; Liu, Chuanshu; Tomljanovic, Tea

    2016-01-01

    Dojo loach, Misgurnus anguillicaudatus is a freshwater fish species of the loach family Cobitidae, using its posterior intestine as an accessory air-breathing organ. Little is known about the molecular regulatory mechanisms in the formation of intestinal air-breathing function of M. anguillicaudatus. Here high-throughput sequencing of mRNAs was performed from six developmental stages of posterior intestine of M. anguillicaudatus: 4-Dph (days post hatch) group, 8-Dph group, 12-Dph group, 20-Dph group, 40-Dph group and Oyd (one-year-old) group. These six libraries were assembled into 81300 unigenes. Totally 40757 unigenes were annotated. Subsequently, 35291 differentially expressed genes (DEGs) were scanned among different developmental stages and clustered into 20 gene expression profiles. Finally, 15 key pathways and 25 key genes were mined, providing potential targets for candidate gene selection involved in formation of intestinal air-breathing function in M. anguillicaudatus. This is the first report of developmental transcriptome of posterior intestine in M. anguillicaudatus, offering a substantial contribution to the sequence resources for this species and providing a deep insight into the formation mechanism of its intestinal air-breathing function. This report demonstrates that M. anguillicaudatus is a good model for studies to identify and characterize the molecular basis of accessory air-breathing organ development in fish. PMID:27545457

  14. 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.

  15. 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.

  16. Magnetohydrodynamic Augmented Propulsion Experiment

    NASA Technical Reports Server (NTRS)

    Litchford, Ron J.; Cole, John; Lineberry, John; Chapman, Jim; Schmidt, Harold; Cook, Stephen (Technical Monitor)

    2002-01-01

    A fundamental obstacle to routine space access is the specific energy limitations associated with chemical fuels. In the case of vertical take-off, the high thrust needed for vertical liftoff and acceleration to orbit translates into power levels in the 10 GW range. Furthermore, useful payload mass fractions are possible only if the exhaust particle energy (i.e., exhaust velocity) is much greater than that available with traditional chemical propulsion. The electronic binding energy released by the best chemical reactions (e.g., LOX/LH2 for example, is less than 2 eV per product molecule (approx. 1.8 eV per H2O molecule), which translates into particle velocities less than 5 km/s. Useful payload fractions, however, will require exhaust velocities exceeding 15 km/s (i.e., particle energies greater than 20 eV). As an added challenge, the envisioned hypothetical RLV (reusable launch vehicle) should accomplish these amazing performance feats while providing relatively low acceleration levels to orbit (2-3g maximum). From such fundamental considerations, it is painfully obvious that planned and current RLV solutions based on chemical fuels alone represent only a temporary solution and can only result in minor gains, at best. What is truly needed is a revolutionary approach that will dramatically reduce the amount of fuel and size of the launch vehicle. This implies the need for new compact high-power energy sources as well as advanced accelerator technologies for increasing engine exhaust velocity. Electromagnetic acceleration techniques are of immense interest since they can be used to circumvent the thermal limits associated with conventional propulsion systems. This paper describes the Magnetohydrodynamic Augmented Propulsion Experiment (MAPX) being undertaken at NASA Marshall Space Flight Center (MSFC). In this experiment, a 1-MW arc heater is being used as a feeder for a 1-MW magnetohydrodynamic (MHD) accelerator. The purpose of the experiment is to demonstrate

  17. Electric propulsion system technology

    NASA Astrophysics Data System (ADS)

    Brophy, John R.; Garner, Charles E.; Goodfellow, Keith D.; Pivirotto, Thomas J.; Polk, James E.

    1992-11-01

    The work performed in fiscal year (FY) 1991 under the Propulsion Technology Program RTOP (Research and Technology Objectives and Plans) No. (55) 506-42-31 for Low-Thrust Primary and Auxiliary Propulsion technology development is described. The objectives of this work fall under two broad categories. The first of these deals with the development of ion engines for primary propulsion in support of solar system exploration. The second with the advancement of steady-state magnetoplasmadynamic (MPD) thruster technology at 100 kW to multimegawatt input power levels. The major technology issues for ion propulsion are demonstration of adequate engine life at the 5 to 10 kW power level and scaling ion engines to power levels of tens to hundreds of kilowatts. Tests of a new technique in which the decelerator grid of a three-grid ion accelerator system is biased negative of neutralizer common potential in order to collect facility induced charge-exchange ions are described. These tests indicate that this SAND (Screen, Accelerator, Negative Decelerator) configuration may enable long duration ion engine endurance tests to be performed at vacuum chamber pressures an order of magnitude higher than previously possible. The corresponding reduction in pumping speed requirements enables endurance tests of 10 kW class ion engines to be performed within the resources of existing technology programs. The results of a successful 5,000-hr endurance of a xenon hollow cathode operating at an emission current of 25 A are described, as well as the initial tests of hollow cathodes operating on a mixture of argon and 3 percent nitrogen. Work performed on the development of carbon/carbon grids, a multi-orifice hollow cathode, and discharge chamber erosion reduction through the addition of nitrogen are also described. Critical applied-field MPD thruster technical issues remain to be resolved, including demonstration of reliable steady-state operation at input powers of hundreds to thousands of

  18. Pulsed plasmoid electric propulsion

    NASA Technical Reports Server (NTRS)

    Bourque, Robert F.; Parks, Paul B.; Tamano, Teruo

    1990-01-01

    A method of electric propulsion is explored where plasmoids such as spheromaks and field reversed configurations (FRC) are formed and then allowed to expand down a diverging conducting shell. The plasmoids contain a toroidal electric current that provides both heating and a confining magnetic field. They are free to translate because there are no externally supplied magnetic fields that would restrict motion. Image currents in the diverging conducting shell keep the plasmoids from contacting the wall. Because these currents translate relative to the wall, losses due to magnetic flux diffusion into the wall are minimized. During the expansion of the plasma in the diverging cone, both the inductive and thermal plasma energy are converted to directed kinetic energy producing thrust. Specific impulses can be in the 4000 to 20000 sec range with thrusts from 0.1 to 1000 Newtons, depending on available power.

  19. Electric propulsion system technology

    NASA Technical Reports Server (NTRS)

    Brophy, John R.; Garner, Charles E.; Goodfellow, Keith D.; Pivirotto, Thomas J.; Polk, James E.

    1992-01-01

    The work performed in fiscal year (FY) 1991 under the Propulsion Technology Program RTOP (Research and Technology Objectives and Plans) No. (55) 506-42-31 for Low-Thrust Primary and Auxiliary Propulsion technology development is described. The objectives of this work fall under two broad categories. The first of these deals with the development of ion engines for primary propulsion in support of solar system exploration. The second with the advancement of steady-state magnetoplasmadynamic (MPD) thruster technology at 100 kW to multimegawatt input power levels. The major technology issues for ion propulsion are demonstration of adequate engine life at the 5 to 10 kW power level and scaling ion engines to power levels of tens to hundreds of kilowatts. Tests of a new technique in which the decelerator grid of a three-grid ion accelerator system is biased negative of neutralizer common potential in order to collect facility induced charge-exchange ions are described. These tests indicate that this SAND (Screen, Accelerator, Negative Decelerator) configuration may enable long duration ion engine endurance tests to be performed at vacuum chamber pressures an order of magnitude higher than previously possible. The corresponding reduction in pumping speed requirements enables endurance tests of 10 kW class ion engines to be performed within the resources of existing technology programs. The results of a successful 5,000-hr endurance of a xenon hollow cathode operating at an emission current of 25 A are described, as well as the initial tests of hollow cathodes operating on a mixture of argon and 3 percent nitrogen. Work performed on the development of carbon/carbon grids, a multi-orifice hollow cathode, and discharge chamber erosion reduction through the addition of nitrogen are also described. Critical applied-field MPD thruster technical issues remain to be resolved, including demonstration of reliable steady-state operation at input powers of hundreds to thousands of

  20. Space station propulsion

    NASA Technical Reports Server (NTRS)

    Jones, Robert E.; Morren, W. Earl; Sovey, James S.; Tacina, Robert R.

    1987-01-01

    Two propulsion systems have been selected for the space station: gaseous H/O rockets for high thrust applications and the multipropellant resistojets for low thrust needs. These two thruster systems integrate very well with the fluid systems on the space station, utilizing waste fluids as their source of propellant. The H/O rocket will be fueled by electrolyzed water and the resistojets will use waste gases collected from the environmental control system and the various laboratories. The results are presented of experimental efforts with H/O and resistojet thrusters to determine their performance and life capability, as well as results of studies to determine the availability of water and waste gases.

  1. Anatomy of Nanoscale Propulsion.

    PubMed

    Yadav, Vinita; Duan, Wentao; Butler, Peter J; Sen, Ayusman

    2015-01-01

    Nature supports multifaceted forms of life. Despite the variety and complexity of these forms, motility remains the epicenter of life. The applicable laws of physics change upon going from macroscales to microscales and nanoscales, which are characterized by low Reynolds number (Re). We discuss motion at low Re in natural and synthetic systems, along with various propulsion mechanisms, including electrophoresis, electrolyte diffusiophoresis, and nonelectrolyte diffusiophoresis. We also describe the newly uncovered phenomena of motility in non-ATP-driven self-powered enzymes and the directional movement of these enzymes in response to substrate gradients. These enzymes can also be immobilized to function as fluid pumps in response to the presence of their substrates. Finally, we review emergent collective behavior arising from interacting motile species, and we discuss the possible biomedical applications of the synthetic nanobots and microbots. PMID:26098511

  2. Pulsed hydrojet propulsion

    SciTech Connect

    Bohachevsky, I.O.; Torrey, M.D.

    1985-01-01

    The pulsed hydrojet is a device in which the water ingested from the free stream is accelerated out of the exhaust pipe to produce thrust. In this report we describe and analyze a way of accelerating the stream of water with pockets of high pressure steam and gas generated inside the stream by an exothermal reaction of suitable propellant injected and dispersed in the water. The velocity increment that must be imparted to the water to produce a substantial thrust need not be very large because the density of the water is comparable to the average density of the accelerated body. Results of the numerical modeling of the proposed jet acceleration mechanism indicate that the hydrojet propulsion device is potentially capable of propelling underwater projectiles at speeds three to five times greater than those currently attainable. Several promising applications of the hydrojet thruster are discussed and evaluated.

  3. Physics of magnetic propulsion

    NASA Astrophysics Data System (ADS)

    Pulatov, V.

    2005-01-01

    The flight of a magnetic vehicle is expected at the expense of the electrodynamic lift and thrust force of interaction with the natural magnetic field and with the eddy currents in ground or water at low altitudes. It would present in future an alternative to rocketry and aviation owing to the expected better efficiency, constant mass and pure ecology. The principles of the magnetic propulsion (Prog Aerospace Sci 2001;37:245-61) allow to substantiate the proposed application and variant of design of the magnetic flight vehicle, to clarify its advantageous properties and to determine the main problems to be solved for its creation. The reviewed questions of its theory show a number of its important advantages. One of them is the possible performance of aerospace and interplanetary flights by the same unit. The proposed calculation basis for the numerical estimations and corresponding numerical examples would allow to image this vehicle structural features and to compare variants.

  4. Hypersonic propulsion research

    NASA Technical Reports Server (NTRS)

    Northam, G. Burton

    1990-01-01

    The development of technology for the modular airframe integrated scramjet has been the focus of hypersonic propulsion research for several years. An part of this research, a variety of inlet concepts have been explored and characterized. The emphasis of the inlet program has been the development of the short (light weight), fixed geometry, side wall compression inlets that operate efficiently over a wide Mach number range. As hypersonic combustion tunnels were developed, programs to study the parameters controlling fuel mixing and combustion with single and multiple strut models were conducted using direct connect test techniques. These various tests supported the design of subscale engine test hardware that integrated inlet and combustor technology and allowed the study of the effect of heat release on thrust and combustor/inlet interaction. A number of subscale engine tests have shown predicted performance levels at Mach 4 and 7 simulated flight conditions. A few of the highlights from this research program are summarized.

  5. Hypersonic propulsion research

    NASA Technical Reports Server (NTRS)

    Northam, G. Burton

    1987-01-01

    The NASA Langley Research Center has conducted hypersonic propulsion research since the 1960s. A variety of inlet concepts were explored and characterized. The emphasis of the inlet program was the development of the short (light weight), fixed geometry, side-wall-compression inlets that operate efficiently over a wide Mach number range. As hypersonic combustion tunnels were developed, programs to study the parameters controlling fuel mixing and combustion with single and multiple strut models were conducted using direct connect test techniques. These various tests supported the design of subscale engine test hardware that integrated inlet and combustor technology and allowed the study of the effect of heat release on thrust and combustor/inlet interaction. A number of subscale engine tests have demonstrated predicted performance levels at Mach 4 and 7 simulated flight conditions.

  6. Magnetohydrodynamic Augmented Propulsion Experiment

    NASA Technical Reports Server (NTRS)

    Litchford, Ron J.

    2008-01-01

    Over the past several years, efforts have been under way to design and develop an operationally flexible research facility for investigating the use of cross-field MHD accelerators as a potential thrust augmentation device for thermal propulsion systems. The baseline configuration for this high-power experimental facility utilizes a 1.5-MWe multi-gas arc-heater as a thermal driver for a 2-MWe MHD accelerator, which resides in a large-bore 2-tesla electromagnet. A preliminary design study using NaK seeded nitrogen as the working fluid led to an externally diagonalized segmented MHD channel configuration based on an expendable heat-sink design concept. The current status report includes a review of engineering/design work and performance optimization analyses and summarizes component hardware fabrication and development efforts, preliminary testing results, and recent progress toward full-up assembly and testing

  7. Solar Thermal Propulsion Test Facility

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Researchers at the Marshall Space Flight Center (MSFC) have designed, fabricated and tested the first solar thermal engine, a non-chemical rocket engine that produces lower thrust but has better thrust efficiency than a chemical combustion engine. MSFC turned to solar thermal propulsion in the early 1990s due to its simplicity, safety, low cost, and commonality with other propulsion systems. Solar thermal propulsion works by acquiring and redirecting solar energy to heat a propellant. This photograph, taken at MSFC's Solar Thermal Propulsion Test Facility, shows a concentrator mirror, a combination of 144 mirrors forming this 18-ft diameter concentrator, and a vacuum chamber that houses the focal point. The 20- by 24-ft heliostat mirror (not shown in this photograph) has a dual-axis control that keeps a reflection of the sunlight on the 18-foot diameter concentrator mirror, which then focuses the sunlight to a 4-in focal point inside the vacuum chamber. The focal point has 10 kilowatts of intense solar power. As part of MSFC's Space Transportation Directorate, the Propulsion Research Center serves as a national resource for research of advanced, revolutionary propulsion technologies. The mission is to move the Nation's capabilities beyond the confines of conventional chemical propulsion into an era of aircraft-like access to Earth-orbit, rapid travel throughout the solar system, and exploration of interstellar space.

  8. Combined microwave science and propulsion

    SciTech Connect

    Palaszewski, B.

    1989-01-01

    The combined use of high-power active science instruments and high-power electric propulsion is investigated with a view to new science opportunities and measurements on future planetary missions. An example of a comet rendezvous mission that could benefit from this combination is discussed. It was found that, with electric propulsion, the launch mass of the comet spacecraft could be reduced by 61-68 percent over the chemical propulsion baseline mission. This high-power spacecraft is also capable of delivering a significant high-power radar science payload to the comet. 28 references.

  9. NASA's Nuclear Thermal Propulsion Project

    NASA Technical Reports Server (NTRS)

    Houts, Michael G.; Mitchell, Doyce P.; Kim, Tony; Emrich, William J.; Hickman, Robert R.; Gerrish, Harold P.; Doughty, Glen; Belvin, Anthony; Clement, Steven; Borowski, Stanley K.; Scott, John; Power, Kevin P.

    2015-01-01

    The fundamental capability of Nuclear Thermal Propulsion (NTP) is game changing for space exploration. A first generation NTP system could provide high thrust at a specific impulse above 900 s, roughly double that of state of the art chemical engines. Characteristics of fission and NTP indicate that useful first generation systems will provide a foundation for future systems with extremely high performance. The role of a first generation NTP in the development of advanced nuclear propulsion systems could be analogous to the role of the DC- 3 in the development of advanced aviation. Progress made under the NTP project could also help enable high performance fission power systems and Nuclear Electric Propulsion (NEP).

  10. Manrating orbital transfer vehicle propulsion

    NASA Technical Reports Server (NTRS)

    Cooper, L. P.

    1985-01-01

    The expended capabilities for Orbital Transfer Vehicles (OTV) which will be needed to meet increased payload requirements for transporting materials and men to geosynchronous orbit are discussed. The requirement to provide manrating offers challenges and opportunities to the propulsion system designers. The propulsion approaches utilized in previous manned space vehicles of the United States are reviewed. The principals of reliability analysis are applied to the Orbit Transfer Vehicle. Propulsion system options are characterized in terms of the test requirements to demonstrate reliability goals and are compared to earlier vehicle approaches.

  11. Advanced Space Fission Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Houts, Michael G.; Borowski, Stanley K.

    2010-01-01

    Fission has been considered for in-space propulsion since the 1940s. Nuclear Thermal Propulsion (NTP) systems underwent extensive development from 1955-1973, completing 20 full power ground tests and achieving specific impulses nearly twice that of the best chemical propulsion systems. Space fission power systems (which may eventually enable Nuclear Electric Propulsion) have been flown in space by both the United States and the Former Soviet Union. Fission is the most developed and understood of the nuclear propulsion options (e.g. fission, fusion, antimatter, etc.), and fission has enjoyed tremendous terrestrial success for nearly 7 decades. Current space nuclear research and technology efforts are focused on devising and developing first generation systems that are safe, reliable and affordable. For propulsion, the focus is on nuclear thermal rockets that build on technologies and systems developed and tested under the Rover/NERVA and related programs from the Apollo era. NTP Affordability is achieved through use of previously developed fuels and materials, modern analytical techniques and test strategies, and development of a small engine for ground and flight technology demonstration. Initial NTP systems will be capable of achieving an Isp of 900 s at a relatively high thrust-to-weight ratio. The development and use of first generation space fission power and propulsion systems will provide new, game changing capabilities for NASA. In addition, development and use of these systems will provide the foundation for developing extremely advanced power and propulsion systems capable of routinely and affordably accessing any point in the solar system. The energy density of fissile fuel (8 x 10(exp 13) Joules/kg) is more than adequate for enabling extensive exploration and utilization of the solar system. For space fission propulsion systems, the key is converting the virtually unlimited energy of fission into thrust at the desired specific impulse and thrust

  12. Enabling Electric Propulsion for Flight

    NASA Technical Reports Server (NTRS)

    Ginn, Starr Renee

    2015-01-01

    Team Seedling project AFRC and LaRC 31ft distributed electric propulsion wing on truck bed up 75 miles per hour for coefficient of lift validation. Convergent Aeronautic Solutions project, sub-project Convergent Electric Propulsion Technologies AFRC, LaRC and GRC, re-winging a 4 passenger Tecnam aircraft with a 31ft distributed electric propulsion wing. Advanced Air Transport Technologies (Fixed Wing), Hybrid Electric Research Theme, developing a series hybrid ironbird and flight sim to study integration and performance challenges in preparation for a 1-2 MW flight project.

  13. Enabling Electric Propulsion for Flight

    NASA Technical Reports Server (NTRS)

    Ginn, Starr

    2014-01-01

    Description of current ARMD projects; Team Seedling project AFRC and LaRC 31ft distributed electric propulsion wing on truck bed up 75 miles per hour for coefficient of lift validation. Convergent Aeronautic Solutions project (new ARMD reorg), sub-project Convergent Electric Propulsion Technologies AFRC, LaRC and GRC, re-winging a 4 passenger Tecnam aircraft with a 31ft distributed electric propulsion wing. Advanced Air Transport Technologies (Fixed Wing), Hybrid Electric Research Theme, developing a series hybrid ironbird and flight sim to study integration and performance challenges in preparation for a 1-2 MW flight project.

  14. MSFC Nuclear Propulsion Materials Development

    NASA Technical Reports Server (NTRS)

    Rogers, J. R.; Cook, B.

    2004-01-01

    Nuclear propulsion systems for spacecraft applications present numerous technical challenges for propulsion systems. They have been the focus of a recent NRA. Challenges inclue: a nuclear reactor subsystem to produce thermal energy; a power conversion subsystem to convert the thermal energy into electrical energy; a propulsion subsystem that utilizes Hall effect thrusters; thruster technologies and high temperature materials to support subsystems. The MSFC Electrostatic Levitation (ESL) Facility provides an ideal platform for the study of high temperature and reactive materials. An overview of the facility and its capabilities will be presented.

  15. NASA research in aircraft propulsion

    NASA Technical Reports Server (NTRS)

    Beheim, M. A.

    1982-01-01

    A broad overview of the scope of research presently being supported by NASA in aircraft propulsion is presented with emphasis on Lewis Research Center activities related to civil air transports, CTOL and V/STOL systems. Aircraft systems work is performed to identify the requirements for the propulsion system that enhance the mission capabilities of the aircraft. This important source of innovation and creativity drives the direction of propulsion research. In a companion effort, component research of a generic nature is performed to provide a better basis for design and provides an evolutionary process for technological growth that increases the capabilities of all types of aircraft. Both are important.

  16. Balancing the competing requirements of air-breathing and display behaviour during male-male interactions in Siamese fighting fish Betta splendens.

    PubMed

    Alton, Lesley A; Portugal, Steven J; White, Craig R

    2013-02-01

    Air-breathing fish of the Anabantoidei group meet their metabolic requirements for oxygen through both aerial and aquatic gas exchange. Siamese fighting fish Betta splendens are anabantoids that frequently engage in aggressive male-male interactions which cause significant increases in metabolic rate and oxygen requirements. These interactions involve opercular flaring behaviour that is thought to limit aquatic oxygen uptake, and combines with the increase in metabolic rate to cause an increase in air-breathing behaviour. Air-breathing events interrupt display behaviour and increase risk of predation, raising the question of how Siamese fighting fish manage their oxygen requirements during agonistic encounters. Using open-flow respirometry, we measured rate of oxygen consumption in displaying fish to determine if males increase oxygen uptake per breath to minimise visits to the surface, or increase their reliance on aquatic oxygen uptake. We found that the increased oxygen requirements of Siamese fighting fish during display behaviour were met by increased oxygen uptake from the air with no significant changes in aquatic oxygen uptake. The increased aerial oxygen uptake was achieved almost entirely by an increase in air-breathing frequency. We conclude that limitations imposed by the reduced gill surface area of air-breathing fish restrict the ability of Siamese fighting fish to increase aquatic uptake, and limitations of the air-breathing organ of anabantoids largely restrict their capacity to increase oxygen uptake per breath. The resulting need to increase surfacing frequency during metabolically demanding agonistic encounters has presumably contributed to the evolution of the stereotyped surfacing behaviour seen during male-male interactions, during which one of the fish will lead the other to the surface, and each will take a breath of air. PMID:23178457

  17. Propulsion Controls and Diagnostics Research in Support of NASA Aeronautics and Exploration Mission Programs

    NASA Technical Reports Server (NTRS)

    Garg, Sanjay

    2011-01-01

    The Controls and Dynamics Branch (CDB) at National Aeronautics and Space Administration (NASA) 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 propulsion controls and diagnostics technologies that will help meet the challenging goals of NASA programs under the Aeronautics Research and Exploration Systems Missions. This paper provides a brief overview of the various CDB tasks in support of the NASA programs. The programmatic structure of the CDB activities is described along with a brief overview of each of the CDB tasks including research objectives, technical challenges, and recent accomplishments. These tasks include active control of propulsion system components, intelligent propulsion diagnostics and control for reliable fault identification and accommodation, distributed engine control, and investigations into unsteady propulsion systems.

  18. Damage Tolerance Assessment Branch

    NASA Technical Reports Server (NTRS)

    Walker, James L.

    2013-01-01

    The Damage Tolerance Assessment Branch evaluates the ability of a structure to perform reliably throughout its service life in the presence of a defect, crack, or other form of damage. Such assessment is fundamental to the use of structural materials and requires an integral blend of materials engineering, fracture testing and analysis, and nondestructive evaluation. The vision of the Branch is to increase the safety of manned space flight by improving the fracture control and the associated nondestructive evaluation processes through development and application of standards, guidelines, advanced test and analytical methods. The Branch also strives to assist and solve non-aerospace related NDE and damage tolerance problems, providing consultation, prototyping and inspection services.

  19. Pen Branch delta expansion

    SciTech Connect

    Nelson, E.A.; Christensen, E.J.; Mackey, H.E.; Sharitz, R.R.; Jensen, J.R.; Hodgson, M.E.

    1984-02-01

    Since 1954, cooling water discharges from K Reactor ({anti X} = 370 cfs {at} 59 C) to Pen Branch have altered vegetation and deposited sediment in the Savannah River Swamp forming the Pen Branch delta. Currently, the delta covers over 300 acres and continues to expand at a rate of about 16 acres/yr. Examination of delta expansion can provide important information on environmental impacts to wetlands exposed to elevated temperature and flow conditions. To assess the current status and predict future expansion of the Pen Branch delta, historic aerial photographs were analyzed using both basic photo interpretation and computer techniques to provide the following information: (1) past and current expansion rates; (2) location and changes of impacted areas; (3) total acreage presently affected. Delta acreage changes were then compared to historic reactor discharge temperature and flow data to see if expansion rate variations could be related to reactor operations.

  20. Gait kinetics of above- and below-branch quadrupedal locomotion in lemurid primates.

    PubMed

    Granatosky, Michael C; Tripp, Cameron H; Schmitt, Daniel

    2016-01-01

    For primates and other mammals moving on relatively thin branches, the ability to effectively adopt both above- and below-branch locomotion is seen as critical for successful arboreal locomotion, and has been considered an important step prior to the evolution of specialized suspensory locomotion within our Order. Yet, little information exists on the ways in which limb mechanics change when animals shift from above- to below-branch quadrupedal locomotion. This study tested the hypothesis that vertical force magnitude and distribution do not vary between locomotor modes, but that the propulsive and braking roles of the forelimb change when animals shift from above- to below-branch quadrupedal locomotion. We collected kinetic data on two lemur species (Varecia variegata and Lemur catta) walking above and below an instrumented arboreal runway. Values for peak vertical, braking and propulsive forces as well as horizontal impulses were collected for each limb. When walking below branch, both species demonstrated a significant shift in limb kinetics compared with above-branch movement. The forelimb became both the primary weight-bearing limb and propulsive organ, while the hindlimb reduced its weight-bearing role and became the primary braking limb. This shift in force distribution represents a shift toward mechanics associated with bimanual suspensory locomotion, a locomotor mode unusual to primates and central to human evolution. The ability to make this change is not accompanied by significant anatomical changes, and thus likely represents an underlying mechanical flexibility present in most primates. PMID:26739686

  1. 1998 JANNAF Propulsion Meeting. Volume 1

    NASA Technical Reports Server (NTRS)

    Eggleston, Debra S. (Editor)

    1998-01-01

    This volume, the first of four volumes, is a collection of 40 unclassified/unlimited-distribution papers which were presented at the 1998 Joint Army-Navy-NASA-Air Force (JANNAF) Propulsion Meeting (JPM), held 15-17 July 1998 at the Cleveland Marriott Downtown at Key Center and the Celebreeze Federal Building in Cleveland, Ohio. The 1998 JPM was co-located with the 1998 American Institute of Aeronautics and Astronautics Joint Propulsion Conference. Specific subjects discussed include reusable liquid boosters, controllable solid propulsion, advanced propellants for the 2.75' rocket system, air-turbo-rocket propulsion, issues in gun propulsion, electric propulsion, liquid engine turbomachinery, and new liquid propulsion technology.

  2. Branch classification: A new mechanism for improving branch predictor performance

    SciTech Connect

    Chang, P.Y.; Hao, E.; Patt, Y.; Yeh, T.Y.

    1996-04-01

    There is wide agreement that one of the most significant impediments to the performance of current and future pipelined superscalar processors is the presence of conditional branches in the instruction stream. Speculative execution is one solution to the branch problem, but speculative work is discarded if a branch is mispredicted. For it to be effective, speculative work is discarded if a branch is mispredicted. For it to be effective, speculative execution requires a very accurate branch predictor; 95% accuracy is not good enough. This paper proposes branch classification, a methodology for building more accurate branch predictors. Branch classification allows an individual branch instruction to be associated with the branch predictor best suited to predict its direction. Using this approach, a hybrid branch predictor can be constructed such that each component branch predictor predicts those branches for which it is best suited. To demonstrate the usefulness of branch classification, an example classification scheme is given and a new hybrid predictor is built based on this scheme which achieves a higher prediction accuracy than any branch predictor previously reported in the literature.

  3. Environmental Hypertonicity Causes Induction of Gluconeogenesis in the Air-Breathing Singhi Catfish, Heteropneustes fossilis

    PubMed Central

    Das, Manas; Banerjee, Bodhisattwa; Choudhury, Mahua G.; Saha, Nirmalendu

    2013-01-01

    The air-breathing singhi catfish (Heteropneustes fossilis) is frequently being challenged by different environmental insults such as hyper-ammonia, dehydration and osmotic stresses in their natural habitats throughout the year. The present study investigated the effect of hyperosmotic stress, due to exposure to hypertonic environment (300 mM mannitol) for 14 days, on gluconeogenesis in this catfish. In situ exposure to hypertonic environment led to significant stimulation of gluconeogenic fluxes from the perfused liver after 7 days of exposure, followed by further increase after 14 days in presence of three different potential gluconeogenic substrates (lactate, pyruvate and glutamate). Environmental hypertonicity also caused a significant increase of activities of key gluconeogenic enzymes, namely phosphoenolpyruvate carboxykinase, fructose 1, 6-bisphosphatase and glucose 6-phosphatase by about 2-6 fold in liver, and 3-6 fold in kidney tissues. This was accompanied by more abundance of enzyme proteins by about 1.8–3.7 fold and mRNAs by about 2.2–5.2 fold in both the tissues with a maximum increase after 14 days of exposure. Hence, the increase in activities of key gluconeogenic enzymes under hypertonic stress appeared to be as a result of transcriptional regulation of genes. Immunocytochemical analysis further confirmed the tissue specific localized expression of these enzymes in both the tissues with the possibility of expressing more in the same localized places. The induction of gluconeogenesis during exposure to environmental hypertonicity possibly occurs as a consequence of changes in hydration status/cell volume of different cell types. Thus, these adaptational strategies related to gluconeogenesis that are observed in this catfish under hypertonic stress probably help in maintaining glucose homeostasis and also for a proper energy supply to support metabolic demands mainly for ion transport and other altered metabolic processes under various

  4. Unusual hepatic mitochondrial arginase in an Indian air-breathing teleost, Heteropneustes fossilis: purification and characterization.

    PubMed

    Srivastava, Shilpee; Ratha, B K

    2013-02-01

    A functional urea cycle with both cytosolic (ARG I) and mitochondrial (ARG II) arginase activity is present in the liver of an ureogenic air-breathing teleost, Heteropneustes fossilis. Antibodies against mammalian ARG II showed no cross-reactivity with the H. fossilis ARG II. ARG II was purified to homogeneity from H. fossilis liver. Purified ARG II showed a native molecular mass of 96 kDa. SDS-PAGE showed a major band at 48 kDa. The native enzyme, therefore, appears to be a homodimer. The pI value of the enzyme was 7.5. The purified enzyme showed maximum activity at pH 10.5 and 55 °C. The K(m) of purified ARG II for l-arginine was 5.25±1.12 mM. L-Ornithine and N(ω)-hydroxy-L-arginine showed mixed inhibition with K(i) values 2.16±0.08 and 0.02±0.004 mM respectively. Mn(+2) and Co(+2) were effective activators of arginase activity. Antibody raised against purified H. fossilis ARG II did not cross-react with fish ARG I, and mammalian ARG I and ARG II. Western blot with the antibodies against purified H. fossilis hepatic ARG II showed cross reactivity with a 96 kDa band on native PAGE and a 48 kDa band on SDS-PAGE. The molecular, immunological and kinetic properties suggest uniqueness of the hepatic mitochondrial ARG II in H. fossilis. PMID:23195132

  5. Unique hepatic cytosolic arginase evolved independently in ureogenic freshwater air-breathing teleost, Heteropneustes fossilis.

    PubMed

    Srivastava, Shilpee; Ratha, B K

    2013-01-01

    Hepatic cytosolic arginase (ARG I), an enzyme of the urea cycle operating in the liver of ureotelic animals, is reported to be present in an ammoniotelic freshwater air-breathing teleost, Heteropneustes fossilis which has ureogenic potential. Antibodies available against mammalian ARG I showed no cross reactivity with the H. fossilis ARG I. We purified unique ARG I from H. fossilis liver. Purified ARG I is a homotrimer with molecular mass 75 kDa and subunit molecular mass of 24 kDa. The pI value of the enzyme was 8.5. It showed maximum activity at pH 10.5 and 55°C. The Km of purified enzyme for L-arginine was 2.65±0.39 mM. L-ornithine and N(ω)-hydroxy-L-arginine showed inhibition of the ARG I activity, with Ki values 0.52±0.02mM and 0.08±0.006mM, respectively. Antibody raised against the purified fish liver ARG I showed exclusive specificity, and has no cross reactivity against fish liver ARG II and mammalian liver ARG I and ARG II. We found another isoform of arginase bound to the outer membrane of the mitochondria which was released by 150-200 mM KCl in the extraction medium. This isoform was immunologically different from the soluble cytosolic and mitochondrial arginase. The results of present study support that hepatic cytosolic arginase evolved in this ureogenic freshwater teleost, H. fossilis. Phylogenetic analysis confirms an independent evolution event that occurred much after the evolution of the cytosolic arginase of ureotelic vertebrates. PMID:23840400

  6. Unique Hepatic Cytosolic Arginase Evolved Independently in Ureogenic Freshwater Air-Breathing Teleost, Heteropneustes fossilis

    PubMed Central

    Srivastava, Shilpee; Ratha, B. K.

    2013-01-01

    Hepatic cytosolic arginase (ARG I), an enzyme of the urea cycle operating in the liver of ureotelic animals, is reported to be present in an ammoniotelic freshwater air-breathing teleost, Heteropneustes fossilis which has ureogenic potential. Antibodies available against mammalian ARG I showed no cross reactivity with the H. fossilis ARG I. We purified unique ARG I from H. fossilis liver. Purified ARG I is a homotrimer with molecular mass 75 kDa and subunit molecular mass of 24 kDa. The pI value of the enzyme was 8.5. It showed maximum activity at pH 10.5 and 55°C. The Km of purified enzyme for L-arginine was 2.65±0.39 mM. L-ornithine and Nω-hydroxy-L-arginine showed inhibition of the ARG I activity, with Ki values 0.52±0.02mM and 0.08±0.006mM, respectively. Antibody raised against the purified fish liver ARG I showed exclusive specificity, and has no cross reactivity against fish liver ARG II and mammalian liver ARG I and ARG II. We found another isoform of arginase bound to the outer membrane of the mitochondria which was released by 150–200 mM KCl in the extraction medium. This isoform was immunologically different from the soluble cytosolic and mitochondrial arginase. The results of present study support that hepatic cytosolic arginase evolved in this ureogenic freshwater teleost, H. fossilis. Phylogenetic analysis confirms an independent evolution event that occurred much after the evolution of the cytosolic arginase of ureotelic vertebrates. PMID:23840400

  7. Analytical Investigation of an Airbreathing, Repetitively Pulsed LSC-Wave Thruster: Part 1

    NASA Astrophysics Data System (ADS)

    Myrabo, L. N.; Borkowski, C. A.; Kaminski, D. A.

    2006-05-01

    The prospects for an airbreathing repetitively pulsed, LSC-wave thruster are assessed from the perspective of both thrust production and radiation heat transfer rates into the vehicle undersurface. Pulsed LSC wave thrusters are characterized by high plasma temperatures (e.g., 11,000 K), moderate overpressures (a function of laser intensity), and subsonic LSC wave propagation velocities. The axisymmetric Lightcraft engine configuration examined in this study has a flat underbody impulsive surface of radius 1.25 m. Energy is supplied to the LSC wave by an annular laser beam converging uniformly from the edges of the disk (i.e., reflected inward towards the axis of symmetry from secondary optics positioned around the entire disc circumference). The LSC wave propagates radially outward toward the edge of the disc. At some point the beam is extinguished, and a new LSC wave is initiated at the disk center. The process is repeated at a frequency that produces the desired thrust, and continued until maximum temperatures are exceeded. Results indicate that thrust levels in the range of 104 to 4×105 N are indeed feasible — i.e., sufficient to sustain a 1 tonne Lightcraft in hover, or accelerate it vertically at 40 g. Depending on the desired thrust and LSC wave geometry, viable PRFs can range from ˜100 Hz up to 750 Hz (or more), pulse energies from 0.01 to 4 MJ, and pulse durations from 10 to 350 ms. Momentum coupling coefficients range from 100 to 1000 N/MW, varying as a function of laser intensity incident upon the LSC wave.

  8. Changes in the blood parameters of an air-breathing fish during different respiratory conditions.

    PubMed

    Singh, B R; Thakur, R N; Yadav, A N

    1976-01-01

    Some of the blood parameters recorded in an air-breathing eel, Amphipnous cuchia under normal respiratory condition during non-breeding period (September-April) are haemoglobin (Hb) concentration 19.26%, haematocrit value 56.16%, RBC number 1.71 million/mm3, RBC size 18.86 X 9.70 mum, mean corpuscular haemoglobin (MCH) 113.4 ng, mean corpuscular haemoglobin concentration (MCHC) 34.2%, blood sugar 77 mg% and ascorbic acid 0.435 mg%. The higher concentration of haemoglobin (19.26%) appears to be related to its obligatory air breathing habit and habitat in a water of low oxygen content. Though a definite trend of increase in the haemoglobin and haematocrit concentration with an increase in the body weight of the fish was lacking, variations were clearly marked related to intrinsic activity of the fish connected with different respiratory conditions. Asphyxiation in a submerged but continuous flow of water (liter/h) for 5 1/2 h resulted in an increase in the above-mentioned parameters to an appreciable extent. These increases were 0.23 million/mm3 in the number of erythrocytes, 6.16% in haemoglobin concentration, 10% in haematocrit value, 20% in blood sugar and 35% in ascorbic acid content. The mean corpuscular haemoglobin showed a decline of 6.2%. Exclusive aerial breathing for 5 1/2 h also caused 7.4% increase in haemoglobin concentration, 9.4% in haematocrit value, 0.14 million/mm3 in RBC number, 20% in blood sugar level, 9% in ascorbic acid content but almost no change in mean corpuscular haemoglobin. The average surface area for diffusion of gases appeared to have reduced by 6.8 mum2 per RBC. PMID:61915

  9. Haematological and ion regulatory effects of nitrite in the air-breathing snakehead fish Channa striata.

    PubMed

    Lefevre, Sjannie; Jensen, Frank B; Huong, Do T T; Wang, Tobias; Phuong, Nguyen T; Bayley, Mark

    2012-08-15

    The tolerance and effects of nitrite on ion balance and haematology were investigated in the striped snakehead, Channa striata Bloch 1793, which is an air-breathing fish with reduced gills of importance for aquaculture in South East Asia. C. striata was nitrite tolerant with a 96 h LC50 of 4.7 mM. Effects of sub-lethal exposures to nitrite (0mM, 1.4mM, and 3.0mM) were determined during a 7-day exposure period. Plasma nitrite increased, but the internal concentration remained well below ambient levels. Extracellular nitrate rose by several mM, indicating that a large proportion of the nitrite taken up was converted to nitrate. Nitrite reacted with erythrocyte haemoglobin (Hb) causing methaemoglobin (metHb) to increase to 30% and nitrosylhaemoglobin (HbNO) to increase to 10% of total Hb. Both metHb and HbNO stabilised after 4 days, and functional Hb levels accordingly never fell below 60% of total Hb. Haematocrit and total Hb were unaffected by nitrite. Although the effects of nitrite exposure seemed minor in terms of plasma nitrite and metHb increases, ion balance was strongly affected. In the high exposure group, total osmolality decreased from 320 mOsm to 260 mOsm, and plasma sodium from 150 mM to 120 mM, while plasma chloride fell from 105 mM to 60mM and plasma bicarbonate rose from 12 mM in controls to 20mM in exposed fish. The extreme changes in ion balance in C. striata are different from the response reported in other fish, and further studies are needed to investigate the mechanism behind the observed changes in regulation. PMID:22516674

  10. Electric propulsion system technology

    NASA Technical Reports Server (NTRS)

    Brophy, John R.; Garner, Charles E.; Goodfellow, Keith D.

    1991-01-01

    The work performed on the Ion Propulsion System Technology Task in FY90 is described. The objectives of this work fall under two broad categories. The first of these deals with issues associated with the application of xenon ion thrusters for primary propulsion of planetary spacecraft, and the second with the investigation of technologies which will facilitate the development of larger, higher power ion thrusters to support more advanced mission applications. Most of the effort was devoted to investigation of the critical issues associated with the use of ion thrusters for planetary spacecraft. These issues may be succinctly referred to as life time, system integration, and throttling. Chief among these is the engine life time. If the engines do not have sufficient life to perform the missions of interest, then the other issues become unimportant. Ion engine life time was investigated through two experimental programs: an investigation into the reduction of ion engine internal sputter erosion through the addition of small quantities of nitrogen, and a long duration cathode life test. In addition, a literature review and analysis of accelerator grid erosion were performed. The nitrogen addition tests indicated that the addition of between 0.5 and 1.0 percent of nitrogen by mass to the xenon propellant results in a reduction in the sputter erosion of discharge chamber components by a factor of between 20 and 50, with negligible reduction in thruster performance. The long duration test of a 6.35-mm dia. xenon hollow cathode is still in progress, and has accumulated more than 4,000 hours of operation at an emission current of 25 A at the time of this writing. One of the major system integration issues concerns possible interactions of the ion thruster produced charge exchange plasma with the spacecraft. A computer model originally developed to describe the behavior of mercury ion thruster charge exchange plasmas was resurrected and modified for xenon propellant. This

  11. Rotational propulsion enabled by inertia.

    PubMed

    Nadal, François; Pak, On Shun; Zhu, LaiLai; Brandt, Luca; Lauga, Eric

    2014-07-01

    The fluid mechanics of small-scale locomotion has recently attracted considerable attention, due to its importance in cell motility and the design of artificial micro-swimmers for biomedical applications. Most studies on the topic consider the ideal limit of zero Reynolds number. In this paper, we investigate a simple propulsion mechanism --an up-down asymmetric dumbbell rotating about its axis of symmetry-- unable to propel in the absence of inertia in a Newtonian fluid. Inertial forces lead to continuous propulsion for all finite values of the Reynolds number. We study computationally its propulsive characteristics as well as analytically in the small-Reynolds-number limit. We also derive the optimal dumbbell geometry. The direction of propulsion enabled by inertia is opposite to that induced by viscoelasticity. PMID:25034393

  12. The Nuclear Cryogenic Propulsion Stage

    NASA Technical Reports Server (NTRS)

    Houts, Michael G.; Kim, Tony; Emrich, William J.; Hickman, Robert R.; Broadway, Jeramie W.; Gerrish, Harold P.; Doughty, Glen; Belvin, Anthony; Borowski, Stanley K.; Scott, John

    2014-01-01

    The fundamental capability of Nuclear Thermal Propulsion (NTP) is game changing for space exploration. A first generation Nuclear Cryogenic Propulsion Stage (NCPS) based on NTP could provide high thrust at a specific impulse above 900 s, roughly double that of state of the art chemical engines. Characteristics of fission and NTP indicate that useful first generation systems will provide a foundation for future systems with extremely high performance. The role of the NCPS in the development of advanced nuclear propulsion systems could be analogous to the role of the DC-3 in the development of advanced aviation. Progres made under the NCPS project could help enable both advanced NTP and advanced Nuclear Electric Propulsion (NEP).

  13. Environmental benefits of chemical propulsion

    NASA Technical Reports Server (NTRS)

    Hayes, Joyce A.; Goldberg, Benjamin E.; Anderson, David M.

    1995-01-01

    This paper identifies the necessity of chemical propulsion to satellite usage and some of the benefits accrued through monitoring global resources and patterns, including the Global Climate Change Model (GCM). The paper also summarized how the satellite observations are used to affect national and international policies. Chemical propulsion, like all environmentally conscious industries, does provide limited, controlled pollutant sources through its manufacture and usage. However, chemical propulsion is the sole source which enables mankind to launch spacecraft and monitor the Earth. The information provided by remote sensing directly affects national and international policies designed to protect the environment and enhance the overall quality of life on Earth. The resultant of chemical propulsion is the capability to reduce overall pollutant emissions to the benefit of mankind.

  14. Trajectory correction propulsion for TOPS

    NASA Technical Reports Server (NTRS)

    Long, H. R.; Bjorklund, R. A.

    1972-01-01

    A blowdown-pressurized hydrazine propulsion system was selected to provide trajectory correction impulse for outer planet flyby spacecraft as the result of cost/mass/reliability tradeoff analyses. Present hydrazine component and system technology and component designs were evaluated for application to the Thermoelectric Outer Planet Spacecraft (TOPS); while general hydrazine technology was adequate, component design changes were deemed necessary for TOPS-type missions. A prototype hydrazine propulsion system was fabricated and fired nine times for a total of 1600 s to demonstrate the operation and performance of the TOPS propulsion configuration. A flight-weight trajectory correction propulsion subsystem (TCPS) was designed for the TOPS based on actual and estimated advanced components.

  15. Propulsion issues, options and trades

    NASA Technical Reports Server (NTRS)

    Forsythe, Doug J.

    1986-01-01

    Several different types of propulsion concepts are discussed: pulsed fission; continuous nuclear fission; chemical; and chemical boost with advanced nuclear fission. Some of the key characteristics of each type are provided, and typical concepts of each are shown.

  16. Vehicle Integrated Propulsion Research Tests

    NASA Technical Reports Server (NTRS)

    Lekki, John D.; Hunter, Gary W.; Simon, Don; Meredith, Roger; Wrbanek, John; Woike, Mark; Tokars, Roger; Guffanti, Marianne; Lyall, Eric

    2013-01-01

    Overview of the Vehicle Integrated Propulsion Research Tests in the Vehicle Systems Safety Technologies project. This overview covers highlights of the completed VIPR I and VIPR II tests and also covers plans for the VIPR III test.

  17. Theory for Plasma Rocket Propulsion

    NASA Astrophysics Data System (ADS)

    Grabbe, Crockett

    2009-11-01

    Electrical propulsion of rockets is developing potentially into the use of 3 different thrusters for future long-distance space missions that primarily involve plasma dynamics. These are the Magnetoplasmadynamic (MPD) Thruster, the Plasma Induction Thruster (PID), and the VASIMIR Thruster. The history of the development of electrical propulsion into these prospects and the current research of particularly the VASIMIR Thruster are reviewed. Theoretical questions that need to be addressed in that development are explored.

  18. Selecting hydrocarbon rocket propulsion technology

    NASA Technical Reports Server (NTRS)

    Martin, J. A.

    1986-01-01

    Past studies have shown that the dry weight of future earth-to-orbit vehicles can be reduced by the combined use of hydrogen and hydrocarbon propulsion compared to all-hydrogen propulsion. This paper shows that the use of certain hydrocarbon engines with hydrogen engines produces the lowest vehicle dry mass. These hydrocarbon engines use propane or RP-1 fuel, hydrogen cooling, and hydrogen-rich gas generators. Integration of the hydrogen and hydrocarbon nozzles is also beneficial.

  19. Nuclear Propulsion in Space (1968)

    ScienceCinema

    None

    2014-06-17

    Project NERVA was an acronym for Nuclear Engine for Rocket Vehicle Application, a joint program of the U.S. Atomic Energy Commission and NASA managed by the Space Nuclear Propulsion Office (SNPO) at the Nuclear Rocket Development Station in Jackass Flats, Nevada U.S.A. Between 1959 and 1972, the Space Nuclear Propulsion Office oversaw 23 reactor tests, both the program and the office ended at the end of 1972.

  20. Propulsion Induced Effects Test Program

    NASA Technical Reports Server (NTRS)

    Cappuccio, Gelsomina; Won, Mark; Bencze, Dan

    1999-01-01

    The objective of this milestone is to assess the propulsion/airframe integration characteristics of the Technology Concept Airplane and design variations through computational analysis and experimental subsonic through supersonic wind tunnel testing. The Milestone will generate a comprehensive CFD and wind tunnel data base of the baseline, and design variations. Emphasis will be placed on establishing the propulsion induced effects on the flight performance of the Technology Concept Airplane with all appropriate wind tunnel corrections.

  1. Nuclear Propulsion in Space (1968)

    SciTech Connect

    2012-06-23

    Project NERVA was an acronym for Nuclear Engine for Rocket Vehicle Application, a joint program of the U.S. Atomic Energy Commission and NASA managed by the Space Nuclear Propulsion Office (SNPO) at the Nuclear Rocket Development Station in Jackass Flats, Nevada U.S.A. Between 1959 and 1972, the Space Nuclear Propulsion Office oversaw 23 reactor tests, both the program and the office ended at the end of 1972.

  2. The NASA Electric Propulsion Program

    NASA Technical Reports Server (NTRS)

    Curran, Francis M.; Brophy, John R.; Bennett, Gary L.

    1993-01-01

    NASA has defined and undertaken an evolutionary technology program for high performance electric propulsion systems, which could greatly affect the logistics weight requirements for such large space structures as Space Station Freedom. Attention is presently given to the development status of hydrazine and high power arcjets, resistojets, the characterization of rocket flows and plumes, electrostatic and electromagnetic propulsion systems, and development programs aimed at the determination of opportune technology-insertion activities.

  3. Rocket-Based Combined-Cycle Propulsion Technology for Access-to-Space Applications

    NASA Technical Reports Server (NTRS)

    Hueter, Uwe

    1999-01-01

    NASA's Office of Aero-Space Technology (OAST) established three major goals, referred to as, "The Three Pillars for Success". The Advanced Space Transportation Program Office (ASTP) at the NASA's Marshall Space Flight Center (MSFC) in Huntsville, Ala. focuses on future space transportation technologies under the "Access to Space" pillar. One of the main activities over the past three years has been on advancing the hydrogen fueled rocket-based combined cycle (RBCC) technologies. The RBCC effort that was completed early this year was the initial step leading to flight demonstrations of the technology for space launch vehicle propulsion. Aerojet and Boeing-Rocketdyne designed, built and ground tested their RBCC engine concepts. In addition, ASTROX, Georgia Institute of Technology, McKinney Associates, Pennsylvania State University (PSU), and University of Alabama in Huntsville conducted supporting activities. The RBCC activity included ground testing of components (e.g., injectors, thrusters, ejectors and inlets) and integrated flowpaths. Inlet testing was performed at the Lewis Research Center's 1 x 1 wind tunnel. All direct connect and free-jet engine testing were conducted at the GASL facilities on Long Island, New York. Testing spanned the Mach range from sea level static to Mach 8. Testing of the rocket-only mode, simulating the final phase of the ascent mission profile, was also performed. The originally planned work on these contracts was completed in 1999. Follow-on activities have been initiated for both hydrogen and hydrocarbon fueled RBCC concepts. Studies to better understand system level issues with the integration of RBCC propulsion with earth-to-orbit vehicles have also been conducted. This paper describes the status, progress and future plans of the RBCC activities funded by NASA/MSFC with a major focus on the benefits of utilizing air-breathing combined-cycle propulsion in access-to-space applications.

  4. Nuclear space propulsion critical technologies

    SciTech Connect

    Clark, J.S.; Borowski, S.K.; Doherty, M.P. )

    1993-01-01

    The National Aeronautics and Space Administration (NASA) has actively pursued technology development for nuclear rocket propulsion systems for possible use on lunar outpost missions, for exploration missions to Mars, and for outer planet and other solar system exploration missions. A number of these technologies have been broadly identified by the ANS National Critical Technologies Panel, as well as the Department of Commerce as [open quotes]Critical Technologies.[close quotes] A Nuclear Propulsion Office was established at the Lewis Research Center in Cleveland, Ohio, to lead nuclear propulsion development for NASA and to establish appropriate interagency working relationships with the U.S. Department of Energy national laboratories for nuclear technology development and with the Department of Defense (DoD). The NASA intercenter and interagency teams and NASA contractors have initiated conceptual design activities and other trade studies that provide the focus for appropriate critical technology development for both nuclear thermal propulsion (NTP) systems and nuclear electric propulsion (NEP) systems. Critical technology issues have been identified and are discussed in this paper. For NTP systems, the heat generated in the nuclear reactor is used to simply heat a propellant such as hydrogen, and then the high-temperature propellant expands through a nozzle to produce thrust. Specific impulse for NTP systems should be on the order of 900 to 950 s-approximately double the best chemical propulsion systems.

  5. Solar Thermal Propulsion Test Facility

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Researchers at the Marshall Space Flight Center (MSFC) have designed, fabricated, and tested the first solar thermal engine, a non-chemical rocket engine that produces lower thrust but has better thrust efficiency than a chemical combustion engine. MSFC turned to solar thermal propulsion in the early 1990s due to its simplicity, safety, low cost, and commonality with other propulsion systems. Solar thermal propulsion works by acquiring and redirecting solar energy to heat a propellant. This photograph shows a fully assembled solar thermal engine placed inside the vacuum chamber at the test facility prior to testing. The 20- by 24-ft heliostat mirror (not shown in this photograph) has a dual-axis control that keeps a reflection of the sunlight on the 18-ft diameter concentrator mirror, which then focuses the sunlight to a 4-in focal point inside the vacuum chamber. The focal point has 10 kilowatts of intense solar power. As part of MSFC's Space Transportation Directorate, the Propulsion Research Center serves as a national resource for research of advanced, revolutionary propulsion technologies. The mission is to move theNation's capabilities beyond the confines of conventional chemical propulsion into an era of aircraft-like access to Earth orbit, rapid travel throughout the solar system, and exploration of interstellar space.

  6. LISA propulsion module separation study

    NASA Astrophysics Data System (ADS)

    Merkowitz, S. M.; Ahmad, A.; Hyde, T. T.; Sweetser, T.; Ziemer, J.; Conkey, S.; Kelly, W., III; Shirgur, B.

    2005-05-01

    The Laser Interferometer Space Antenna (LISA) mission is a space-borne gravitational wave detector consisting of three sciencecraft in heliocentric orbit. Each sciencecraft is delivered to its operational orbit by a propulsion module. Because of the strict thermal and mass balancing requirements of LISA, the baseline mission concept requires that the propulsion module separate from the sciencecraft after delivery. The only propulsion system currently included in the sciencecraft design are micronewton level thrusters, such as field emission electric propulsion (FEEP) or colloid thrusters, that are used to balance the 30 40 µN of solar radiation pressure and provide the drag-free and attitude control of the sciencecraft. Due to these thrusters' limited authority, the separation of the propulsion module from the sciencecraft must be well controlled to not induce a large tip-off rotation of the sciencecraft. We present here the results of a study of the propulsion module separation system requirements that are necessary to safely deliver the three LISA sciencecraft to their final operational orbits.

  7. Electric propulsion for small satellites

    NASA Astrophysics Data System (ADS)

    Keidar, Michael; Zhuang, Taisen; Shashurin, Alexey; Teel, George; Chiu, Dereck; Lukas, Joseph; Haque, Samudra; Brieda, Lubos

    2015-01-01

    Propulsion is required for satellite motion in outer space. The displacement of a satellite in space, orbit transfer and its attitude control are the task of space propulsion, which is carried out by rocket engines. Electric propulsion uses electric energy to energize or accelerate the propellant. The electric propulsion, which uses electrical energy to accelerate propellant in the form of plasma, is known as plasma propulsion. Plasma propulsion utilizes the electric energy to first, ionize the propellant and then, deliver energy to the resulting plasma leading to plasma acceleration. Many types of plasma thrusters have been developed over last 50 years. The variety of these devices can be divided into three main categories dependent on the mechanism of acceleration: (i) electrothermal, (ii) electrostatic and (iii) electromagnetic. Recent trends in space exploration associate with the paradigm shift towards small and efficient satellites, or micro- and nano-satellites. A particular example of microthruster considered in this paper is the micro-cathode arc thruster (µCAT). The µCAT is based on vacuum arc discharge. Thrust is produced when the arc discharge erodes some of the cathode at high velocity and is accelerated out the nozzle by a Lorentz force. The thrust amount is controlled by varying the frequency of pulses with demonstrated range to date of 1-50 Hz producing thrust ranging from 1 µN to 0.05 mN.

  8. Mars Rocket Propulsion System

    NASA Technical Reports Server (NTRS)

    Zubrin, Robert; Harber, Dan; Nabors, Sammy

    2008-01-01

    A report discusses the methane and carbon monoxide/LOX (McLOx) rocket for ascent from Mars as well as other critical space propulsion tasks. The system offers a specific impulse over 370 s roughly 50 s higher than existing space-storable bio-propellants. Current Mars in-situ propellant production (ISPP) technologies produce impure methane and carbon monoxide in various combinations. While separation and purification of methane fuel is possible, it adds complexity to the propellant production process and discards an otherwise useful fuel product. The McLOx makes such complex and wasteful processes unnecessary by burning the methane/CO mixtures produced by the Mars ISPP systems without the need for further refinement. Despite the decrease in rocket-specific impulse caused by the CO admixture, the improvement offered by concomitant increased propellant density can provide a net improvement in stage performance. One advantage is the increase of the total amount of propellant produced, but with a decrease in mass and complexity of the required ISPP plant. Methane/CO fuel mixtures also may be produced by reprocessing the organic wastes of a Moon base or a space station, making McLOx engines key for a human Lunar initiative or the International Space Station (ISS) program. Because McLOx propellant components store at a common temperature, very lightweight and compact common bulkhead tanks can be employed, improving overall stage performance further.

  9. Hybrid Propulsion Technology Program

    NASA Technical Reports Server (NTRS)

    Jensen, G. E.; Holzman, A. L.

    1990-01-01

    Future launch systems of the United States will require improvements in booster safety, reliability, and cost. In order to increase payload capabilities, performance improvements are also desirable. The hybrid rocket motor (HRM) offers the potential for improvements in all of these areas. The designs are presented for two sizes of hybrid boosters, a large 4.57 m (180 in.) diameter booster duplicating the Advanced Solid Rocket Motor (ASRM) vacuum thrust-time profile and smaller 2.44 m (96 in.), one-quater thrust level booster. The large booster would be used in tandem, while eight small boosters would be used to achieve the same total thrust. These preliminary designs were generated as part of the NASA Hybrid Propulsion Technology Program. This program is the first phase of an eventual three-phaes program culminating in the demonstration of a large subscale engine. The initial trade and sizing studies resulted in preferred motor diameters, operating pressures, nozzle geometry, and fuel grain systems for both the large and small boosters. The data were then used for specific performance predictions in terms of payload and the definition and selection of the requirements for the major components: the oxidizer feed system, nozzle, and thrust vector system. All of the parametric studies were performed using realistic fuel regression models based upon specific experimental data.

  10. Asymmetrical Capacitors for Propulsion

    NASA Technical Reports Server (NTRS)

    Canning, Francis X.; Melcher, Cory; Winet, Edwin

    2004-01-01

    Asymmetrical Capacitor Thrusters have been proposed as a source of propulsion. For over eighty years, it has been known that a thrust results when a high voltage is placed across an asymmetrical capacitor, when that voltage causes a leakage current to flow. However, there is surprisingly little experimental or theoretical data explaining this effect. This paper reports on the results of tests of several Asymmetrical Capacitor Thrusters (ACTs). The thrust they produce has been measured for various voltages, polarities, and ground configurations and their radiation in the VHF range has been recorded. These tests were performed at atmospheric pressure and at various reduced pressures. A simple model for the thrust was developed. The model assumed the thrust was due to electrostatic forces on the leakage current flowing across the capacitor. It was further assumed that this current involves charged ions which undergo multiple collisions with air. These collisions transfer momentum. All of the measured data was consistent with this model. Many configurations were tested, and the results suggest general design principles for ACTs to be used for a variety of purposes.

  11. Radioiodinated branched carbohydrates

    DOEpatents

    Goodman, Mark M.; Knapp, Jr., Furn F.

    1989-01-01

    A radioiodinated branched carbohydrate for tissue imaging. Iodine-123 is stabilized in the compound by attaching it to a vinyl functional group that is on the carbohydrate. The compound exhibits good uptake and retention and is promising in the development of radiopharmaceuticals for brain, heart and tumor imaging.

  12. Front Range Branch Officers

    NASA Astrophysics Data System (ADS)

    The Front Range Branch of AGU has installed officers for 1990: Ray Noble, National Center for Atmospheric Research, chair; Sherry Oaks, U.S. Geological Survey, chair-elect; Howard Garcia, NOAA, treasurer; Catharine Skokan, Colorado School of Mines, secretary. JoAnn Joselyn of NOAA is past chair. Members at large are Wallace Campbell, NOAA; William Neff, USGS; and Stephen Schneider, NCAR.

  13. Propulsion Technology Needs for Exploration

    NASA Technical Reports Server (NTRS)

    Brown, Thomas

    2007-01-01

    The objectives of currently planned exploration efforts, as well as those further in the future, require significant advancements in propulsion technologies. The current Lunar exploration architecture has set goals and mission objectives that necessitate the use of new systems and the extension of existing technologies beyond present applications. In the near term, the majority of these technologies are the result of a need to apply high performing cryogenic propulsion systems to long duration in-space applications. Advancement of cryogenic propulsion to these applications is crucial to provide higher performing propulsion systems that reduce the vehicle masses; enhance the safety of vehicle systems and ground operations; and provide a path for In-situ Resource Utilization (ISRU).Use of a LOX/LH2 main propulsion system for Lunar Lander Descent is a top priority because more conventional storable propellants are far from meeting the performance needs of the current architecture. While LOX/LH2 pump feed engines have been used in flight applications for many years, these engines have limited throttle capabilities. Engines that are capable of much greater throttling while still meeting high performance goals are a necessity to achieving exploration goals. Applications of LOX/CH4 propulsion to Lander ascent propulsion systems and reaction control systems are also if interest because of desirable performance and operations improvements over conventional storable systems while being more suitable for use of in-situ produced propellants. Within the current lunar architecture, use of cryogenic propulsion for the Earth Departure Stage and Lunar Lander elements also necessitate the need for advanced Cryogenic Fluid Management technologies. These technologies include long duration propellant storage/distribution, low-gravity propellant management, cryogenic couplings and disconnects, light weight composite tanks and support structure, and subsystem integration. In addition to

  14. Perspective use of direct human blood as an energy source in air-breathing hybrid microfluidic fuel cells

    NASA Astrophysics Data System (ADS)

    Dector, A.; Escalona-Villalpando, R. A.; Dector, D.; Vallejo-Becerra, V.; Chávez-Ramírez, A. U.; Arriaga, L. G.; Ledesma-García, J.

    2015-08-01

    This work presents a flexible and light air-breathing hybrid microfluidic fuel cell (HμFC) operated under biological conditions. A mixture of glucose oxidase, glutaraldehyde, multi-walled carbon nanotubes and vulcan carbon (GOx/VC-MWCNT-GA) was used as the bioanode. Meanwhile, integrating an air-exposed electrode (Pt/C) as the cathode enabled direct oxygen delivery from air. The microfluidic fuel cell performance was evaluated using glucose obtained from three different sources as the fuel: 5 mM glucose in phosphate buffer, human serum and human blood. For the last fuel, an open circuit voltage and maximum power density of 0.52 V and 0.20 mW cm-2 (at 0.38 V) were obtained respectively; meanwhile the maximum current density was 1.1 mA cm-2. Furthermore, the stability of the device was measured in terms of recovery after several polarization curves, showing excellent results. Although this air-breathing HμFC requires technological improvements before being tested in a biomedical device, it represents the best performance to date for a microfluidic fuel cell using human blood as glucose source.

  15. Computational modeling of air-breathing microfluidic fuel cells with flow-over and flow-through anodes

    NASA Astrophysics Data System (ADS)

    Zhang, Biao; Ye, Ding-ding; Sui, Pang-Chieh; Djilali, Ned; Zhu, Xun

    2014-08-01

    A three-dimensional computational model for air-breathing microfluidic fuel cells (AMFCs) with flow-over and flow-through anodes is developed. The coupled multiphysics phenomena of fluid flow, species transport and electrochemical reactions are resolved numerically. The model has been validated against experimental data using an in-house AMFC prototype with a flow-through anode. Characteristics of fuel transfer and fuel crossover for both types of anodes are investigated. The model results reveal that the fuel transport to the flow-over anode is intrinsically limited by the fuel concentration boundary layer. Conversely, fuel transport for the flow-through anode is convectively enhanced by the permeate flow, and no concentration boundary layer is observed. An unexpected additional advantage of the flow-through anode configuration is lower parasitic (crossover) current density than the flow-over case at practical low flow rates. Cell performance of the flow-through case is found to be limited by reaction kinetics. The present model provides insights into the fuel transport and fuel crossover in air-breathing microfluidic fuel cells and provides guidance for further design and operation optimization.

  16. Magnetohydrodynamic sea water propulsion

    SciTech Connect

    Petrick, M.; Thomas, A.; Genens, L.; Libera, J.; Nietert, R.; Bouillard, J.; Pierson, E.; Hill, D.; Picologlou, B.; Ohlsson, O.; Kasprzyk, T.; Berry, G.

    1991-01-01

    An experimental and theoretical investigation of a large scale MHD propulsor has been undertaken whose objectives are to (1) investigate the transient and steady state performance of the thruster over operating parameter ranges that are compatible with achievement of high efficiency, (2) to quantify the principal loss mechanisms within the thruster and (3) to obtain preliminary hydroacoustic data. The performance of the thruster was first investigated theoretically with a 3-D code to quantify the loss mechanisms and identify experimental parameter ranges of interest. The loss mechanisms of interest are ohmic losses within the channel and those resulting from electrical currents at the entrance and exit of the thruster, and enhanced frictional losses. The analysis indicated that the relative importance of the loss mechanisms was a function of the thruster design and operating parameters. The experimental investigation of the large scale propulsor is being conducted on a sea water test facility that was designed to match the capabilities of a large 6-T superconducting magnet. The facility design was such that {approximately}90{degrees} of all losses occurred within the propulsion test train (inlet nozzle, propulsor and diffuser) thus facilitating isolation of the loss mechanisms. The test thruster itself is heavily instrumented to provide local measurements of velocity, pressure, and electric fields. The predicted overall thruster performance and value of the loss mechanisms will be compared with measured values. Comparisons will also be presented of the voltage gradients between electrodes, overall thruster efficiency, axial pressure gradients across the propulsor, change in velocity profiles, axial and vertical current distributions and exit distribution of the electrolytic gases.

  17. Magnetohydrodynamic sea water propulsion

    SciTech Connect

    Petrick, M.; Thomas, A.; Genens, L.; Libera, J.; Nietert, R.; Bouillard, J.; Pierson, E.; Hill, D.; Picologlou, B.; Ohlsson, O.; Kasprzyk, T.; Berry, G.

    1991-12-31

    An experimental and theoretical investigation of a large scale MHD propulsor has been undertaken whose objectives are to (1) investigate the transient and steady state performance of the thruster over operating parameter ranges that are compatible with achievement of high efficiency, (2) to quantify the principal loss mechanisms within the thruster and (3) to obtain preliminary hydroacoustic data. The performance of the thruster was first investigated theoretically with a 3-D code to quantify the loss mechanisms and identify experimental parameter ranges of interest. The loss mechanisms of interest are ohmic losses within the channel and those resulting from electrical currents at the entrance and exit of the thruster, and enhanced frictional losses. The analysis indicated that the relative importance of the loss mechanisms was a function of the thruster design and operating parameters. The experimental investigation of the large scale propulsor is being conducted on a sea water test facility that was designed to match the capabilities of a large 6-T superconducting magnet. The facility design was such that {approximately}90{degrees} of all losses occurred within the propulsion test train (inlet nozzle, propulsor and diffuser) thus facilitating isolation of the loss mechanisms. The test thruster itself is heavily instrumented to provide local measurements of velocity, pressure, and electric fields. The predicted overall thruster performance and value of the loss mechanisms will be compared with measured values. Comparisons will also be presented of the voltage gradients between electrodes, overall thruster efficiency, axial pressure gradients across the propulsor, change in velocity profiles, axial and vertical current distributions and exit distribution of the electrolytic gases.

  18. Megawatt Electromagnetic Plasma Propulsion

    NASA Technical Reports Server (NTRS)

    Gilland, James; Lapointe, Michael; Mikellides, Pavlos

    2003-01-01

    The NASA Glenn Research Center program in megawatt level electric propulsion is centered on electromagnetic acceleration of quasi-neutral plasmas. Specific concepts currently being examined are the Magnetoplasmadynamic (MPD) thruster and the Pulsed Inductive Thruster (PIT). In the case of the MPD thruster, a multifaceted approach of experiments, computational modeling, and systems-level models of self field MPD thrusters is underway. The MPD thruster experimental research consists of a 1-10 MWe, 2 ms pulse-forming-network, a vacuum chamber with two 32 diffusion pumps, and voltage, current, mass flow rate, and thrust stand diagnostics. Current focus is on obtaining repeatable thrust measurements of a Princeton Benchmark type self field thruster operating at 0.5-1 gls of argon. Operation with hydrogen is the ultimate goal to realize the increased efficiency anticipated using the lighter gas. Computational modeling is done using the MACH2 MHD code, which can include real gas effects for propellants of interest to MPD operation. The MACH2 code has been benchmarked against other MPD thruster data, and has been used to create a point design for a 3000 second specific impulse (Isp) MPD thruster. This design is awaiting testing in the experimental facility. For the PIT, a computational investigation using MACH2 has been initiated, with experiments awaiting further funding. Although the calculated results have been found to be sensitive to the initial ionization assumptions, recent results have agreed well with experimental data. Finally, a systems level self-field MPD thruster model has been developed that allows for a mission planner or system designer to input Isp and power level into the model equations and obtain values for efficiency, mass flow rate, and input current and voltage. This model emphasizes algebraic simplicity to allow its incorporation into larger trajectory or system optimization codes. The systems level approach will be extended to the pulsed inductive

  19. NASA Glenn Research in Controls and Diagnostics for Intelligent Aerospace Propulsion Systems

    NASA Technical Reports Server (NTRS)

    2005-01-01

    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. Also the propulsion systems required to enable the NASA (National Aeronautics and Space Administration) Vision for Space Exploration in an affordable manner will need to have high reliability, safety and autonomous operation capability. The Controls and Dynamics Branch at NASA 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 paper 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.

  20. Research Opportunities in Space Propulsion

    NASA Technical Reports Server (NTRS)

    Rodgers, Stephen L.

    2007-01-01

    Rocket propulsion determines the primary characteristics of any space vehicle; how fast and far it can go, its lifetime, and its capabilities. It is the primary factor in safety and reliability and the biggest cost driver. The extremes of heat and pressure produced by propulsion systems push the limits of materials used for manufacturing. Space travel is very unforgiving with little room for errors, and so many things can go wrong with these very complex systems. So we have to plan for failure and that makes it costly. But what is more exciting than the roar of a rocket blasting into space? By its nature the propulsion world is conservative. The stakes are so high at every launch, in terms of payload value or in human life, that to introduce new components to a working, qualified system is extremely difficult and costly. Every launch counts and no risks are tolerated, which leads to the space world's version of Catch-22:"You can't fly till you flown." The last big 'game changer' in propulsion was the use of liquid hydrogen as a fuel. No new breakthrough, low cost access to space system will be developed without new efficient propulsion systems. Because there is no large commercial market driving investment in propulsion, what propulsion research is done is sponsored by government funding agencies. A further difficulty in propulsion technology development is that there are so few new systems flying. There is little opportunity to evolve propulsion technologies and to update existing systems with results coming out of research as there is in, for example, the auto industry. The biggest hurdle to space exploration is getting off the ground. The launch phase will consume most of the energy required for any foreseeable space exploration mission. The fundamental physical energy requirements of escaping earth's gravity make it difficult. It takes 60,000 kJ to put a kilogram into an escape orbit. The vast majority (-97%) of the energy produced by a launch vehicle is used

  1. Atomic branching in molecules

    NASA Astrophysics Data System (ADS)

    Estrada, Ernesto; Rodríguez-Velázquez, Juan A.; Randić, Milan

    A graph theoretic measure of extended atomic branching is defined that accounts for the effects of all atoms in the molecule, giving higher weight to the nearest neighbors. It is based on the counting of all substructures in which an atom takes part in a molecule. We prove a theorem that permits the exact calculation of this measure based on the eigenvalues and eigenvectors of the adjacency matrix of the graph representing a molecule. The definition of this measure within the context of the Hückel molecular orbital (HMO) and its calculation for benzenoid hydrocarbons are also studied. We show that the extended atomic branching can be defined using any real symmetric matrix, as well as any Hermitian (self-adjoint) matrix, which permits its calculation in topological, geometrical, and quantum chemical contexts.

  2. Basic research for future electric propulsion

    NASA Technical Reports Server (NTRS)

    Jahn, R. G.

    1985-01-01

    It is pointed out that the evolution of electric propulsion over the past two and a half decades has been constrained by the interaction of three broad factors, including the physics and dynamics of the propellants, the dynamical and logistical requirements of the mission, and the technological realities of materials, power sources, and thermal management. A projection of the future of electric propulsion requires, therefore, a simultaneous reassessment of all three factors. Aspects of mission specification and power systems are discussed, and basic research needed for future electric propulsion applications is considered. Attention is given to electrostatic propulsion, electrothermal propulsion, electromagnetic propulsion, electrothermal/electromagnetic hybrids, novel concepts, and ancillary concerns.

  3. LISA Propulsion Module Separation Study

    NASA Technical Reports Server (NTRS)

    Merkowitz, Stephen

    2004-01-01

    The Laser Interferometer Space Antenna (LISA) mission is a space-borne gravitational wave detector consisting of three spacecraft in heliocentric orbit. Each spacecraft is delivered to it operational orbit by a propulsion module. Because of the strict thermal and mass balancing requirements of LISA, the baseline mission concept requires that the propulsion module separate from the sciencecraft after delivery. The only propulsion system currently baselined for the sciencecraft are micronewton level thrusters, such as FEEP or colloid thrusters, that are used to balance the 30-40 microN of solar radiation pressure and provide the drag-free and attitude control of the spacecraft. Due to these thrusters limited authority, the separation of the propulsion module from the sciencecraft must be well controlled to not induce a large tip-off rotation of the sciencecraft. We present here the results of a design study of the propulsion module separation system that is shown to safely deliver the LISA sciencecraft to its final operational orbit.

  4. Space station propulsion test bed

    NASA Technical Reports Server (NTRS)

    Briley, G. L.; Evans, S. A.

    1989-01-01

    A test bed was fabricated to demonstrate hydrogen/oxygen propulsion technology readiness for the intital operating configuration (IOC) space station application. The test bed propulsion module and computer control system were delivered in December 1985, but activation was delayed until mid-1986 while the propulsion system baseline for the station was reexamined. A new baseline was selected with hydrogen/oxygen thruster modules supplied with gas produced by electrolysis of waste water from the space shuttle and space station. As a result, an electrolysis module was designed, fabricated, and added to the test bed to provide an end-to-end simulation of the baseline system. Subsequent testing of the test bed propulsion and electrolysis modules provided an end-to-end demonstration of the complete space station propulsion system, including thruster hot firings using the oxygen and hydrogen generated from electrolysis of water. Complete autonomous control and operation of all test bed components by the microprocessor control system designed and delivered during the program was demonstrated. The technical readiness of the system is now firmly established.

  5. Propulsion System Modeling and Simulation

    NASA Technical Reports Server (NTRS)

    Tai, Jimmy C. M.; McClure, Erin K.; Mavris, Dimitri N.; Burg, Cecile

    2002-01-01

    The Aerospace Systems Design Laboratory at the School of Aerospace Engineering in Georgia Institute of Technology has developed a core competency that enables propulsion technology managers to make technology investment decisions substantiated by propulsion and airframe technology system studies. This method assists the designer/manager in selecting appropriate technology concepts while accounting for the presence of risk and uncertainty as well as interactions between disciplines. This capability is incorporated into a single design simulation system that is described in this paper. This propulsion system design environment is created with a commercially available software called iSIGHT, which is a generic computational framework, and with analysis programs for engine cycle, engine flowpath, mission, and economic analyses. iSIGHT is used to integrate these analysis tools within a single computer platform and facilitate information transfer amongst the various codes. The resulting modeling and simulation (M&S) environment in conjunction with the response surface method provides the designer/decision-maker an analytical means to examine the entire design space from either a subsystem and/or system perspective. The results of this paper will enable managers to analytically play what-if games to gain insight in to the benefits (and/or degradation) of changing engine cycle design parameters. Furthermore, the propulsion design space will be explored probabilistically to show the feasibility and viability of the propulsion system integrated with a vehicle.

  6. Swimming & Propulsion in Viscoelastic Media

    NASA Astrophysics Data System (ADS)

    Arratia, Paulo

    2012-02-01

    Many microorganisms have evolved within complex fluids, which include soil, intestinal fluid, and mucus. The material properties or rheology of such fluids can strongly affect an organism's swimming behavior. A major challenge is to understand the mechanism of propulsion in media that exhibit both solid- and fluid-like behavior, such as viscoelastic fluids. In this talk, we present experiments that explore the swimming behavior of biological organisms and artificial particles in viscoelastic media. The organism is the nematode Caenorhabditis elegans, a roundworm widely used for biological research that swims by generating traveling waves along its body. Overall, we find that fluid elasticity hinders self-propulsion compared to Newtonian fluids due to the enhanced resistance to flow near hyperbolic points for viscoelastic fluids. As fluid elasticity increases, the nematode's propulsion speed decreases. These results are consistent with recent theoretical models for undulating sheets and cylinders. In order to gain further understanding on propulsion in viscoelastic media, we perform experiments with simple reciprocal artificial `swimmers' (magnetic dumbbell particles) in polymeric and micellar solutions. We find that self-propulsion is possible in viscoelastic media even if the motion is reciprocal.

  7. Underwater branch connection study

    SciTech Connect

    Not Available

    1992-06-01

    This report was prepared with the object of developing guidelines for designing underwater connections of branch pipelines to main lines at existing tap valves and with hot taps in diver accessible water depths. The report considers ANSI Classes 600 and 900 branch pipelines of up to twelve inches in diameter that conform to API Specification 5L minimum. Loads due to gravity, buoyancy, intemal and external pressure, thermal expansion, hydrodynamics and random events are considered. External corrosion, temperature, cover, bottom conditions, stability, testing, commissioning, trenching, and pigging are also addressed. A general discussion of these issues is included in the body of the report. Methods of analysis are included in the appendices and in various references. Lotus 123'' spreadsheets that compute the expansion stresses resulting from pressure and temperature at points on a generic piping geometry are presented. A program diskette is included with the report. The report summarizes, and draws from, the results of a survey of the relevant practice and experience of fifteen gas pipeline operating companies. The survey indicates that most existing branch connections do not provide for pigging of the lateral lines, but that there is a growing consensus that cleaning and inspection pigging of lateral lines is desirable or necessary.

  8. Automated Rocket Propulsion Test Management

    NASA Technical Reports Server (NTRS)

    Walters, Ian; Nelson, Cheryl; Jones, Helene

    2007-01-01

    The Rocket Propulsion Test-Automated Management System provides a central location for managing activities associated with Rocket Propulsion Test Management Board, National Rocket Propulsion Test Alliance, and the Senior Steering Group business management activities. A set of authorized users, both on-site and off-site with regard to Stennis Space Center (SSC), can access the system through a Web interface. Web-based forms are used for user input with generation and electronic distribution of reports easily accessible. Major functions managed by this software include meeting agenda management, meeting minutes, action requests, action items, directives, and recommendations. Additional functions include electronic review, approval, and signatures. A repository/library of documents is available for users, and all items are tracked in the system by unique identification numbers and status (open, closed, percent complete, etc.). The system also provides queries and version control for input of all items.

  9. Breakthrough Propulsion Physics Research Program

    NASA Technical Reports Server (NTRS)

    Millis, Marc G.

    1996-01-01

    In 1996, a team of government, university and industry researchers proposed a program to seek the ultimate breakthroughs in space transportation: propulsion that requires no propellant mass, propulsion that can approach and, if possible, circumvent light speed, and breakthrough methods of energy production to power such devices. This Breakthrough Propulsion Physics program, managed by Lewis Research Center, is one part of a comprehensive, long range Advanced Space Transportation Plan managed by Marshall Space Flight Center. Because the breakthrough goals are beyond existing science, a main emphasis of this program is to establish metrics and ground rules to produce near-term credible progress toward these incredible possibilities. An introduction to the emerging scientific possibilities from which such solutions can be sought is also presented.

  10. The Need for Fusion Propulsion

    NASA Technical Reports Server (NTRS)

    Cassibry, Jason

    2005-01-01

    Fusion propulsion is inevitable if the human race remains dedicated to exploration of the solar system. There are fundamental reasons why fusion surpasses more traditional approaches to routine crewed missions to Mars, crewed missions to the outer planets, and deep space high speed robotic missions, assuming that reduced trip times, increased payloads, and higher available power are desired. A recent series of informal discussions were held among members from government, academia, and industry concerning fusion propulsion. We compiled a sufficient set of arguments for utilizing fusion in space. If the U.S. is to lead the effort and produce a working system in a reasonable amount of time, NASA must take the initiative, relying on, but not waiting for, DOE guidance. In this talk those arguments for fusion propulsion are presented, along with fusion enabled mission examples, fusion technology trade space, and a proposed outline for future efforts.

  11. Nuclear thermal propulsion workshop overview

    NASA Technical Reports Server (NTRS)

    Clark, John S.

    1991-01-01

    NASA is planning an Exploration Technology Program as part of the Space Exploration Initiative to return U.S. astronauts to the moon, conduct intensive robotic exploration of the moon and Mars, and to conduct a piloted mission to Mars by 2019. Nuclear Propulsion is one of the key technology thrust for the human mission to Mars. The workshop addresses NTP (Nuclear Thermal Rocket) technologies with purpose to: assess the state-of-the-art of nuclear propulsion concepts; assess the potential benefits of the concepts for the mission to Mars; identify critical, enabling technologies; lay-out (first order) technology development plans including facility requirements; and estimate the cost of developing these technologies to flight-ready status. The output from the workshop will serve as a data base for nuclear propulsion project planning.

  12. Main Propulsion Test Article (MPTA)

    NASA Technical Reports Server (NTRS)

    Snoddy, Cynthia

    2010-01-01

    Scope: The Main Propulsion Test Article integrated the main propulsion subsystem with the clustered Space Shuttle Main Engines, the External Tank and associated GSE. The test program consisted of cryogenic tanking tests and short- and long duration static firings including gimbaling and throttling. The test program was conducted on the S1-C test stand (Position B-2) at the National Space Technology Laboratories (NSTL)/Stennis Space Center. 3 tanking tests and 20 hot fire tests conducted between December 21 1 1977 and December 17, 1980 Configuration: The main propulsion test article consisted of the three space shuttle main engines, flightweight external tank, flightweight aft fuselage, interface section and a boilerplate mid/fwd fuselage truss structure.

  13. Space Station Freedom propulsion activities

    NASA Technical Reports Server (NTRS)

    Spera, David A. (Editor)

    1990-01-01

    The technical highlights and accomplishments made at NASA LeRC in the development of the Space Station Freedom (SSF) propulsion system are discussed. The objectives are as follows: develop and characterize resistojet-thruster components and assemblies; develop and characterize hydrogen-oxygen thruster components; and conduct system trade studies. The research projects primarily characterize propulsion performance and life. Other tests include environmental impacts, such as exhaust gas profiles and electromagnetic interference. The technical activities that are highlighted are being conducted at LeRC within the Aerospace Technology and Space Station Freedom directorates. These activities include the following: derivation of design analysis models; trade studies of design options; propulsion system impact studies; and component testing for characterization and design verification.

  14. Fast-starting after a breath: air-breathing motions are kinematically similar to escape responses in the catfish Hoplosternum littorale.

    PubMed

    Domenici, Paolo; Norin, Tommy; Bushnell, Peter G; Johansen, Jacob L; Skov, Peter Vilhelm; Svendsen, Morten B S; Steffensen, John F; Abe, Augusto S

    2014-01-01

    Fast-starts are brief accelerations commonly observed in fish within the context of predator-prey interactions. In typical C-start escape responses, fish react to a threatening stimulus by bending their body into a C-shape during the first muscle contraction (i.e. stage 1) which provides a sudden acceleration away from the stimulus. Recently, similar C-starts have been recorded in fish aiming at a prey. Little is known about C-starts outside the context of predator-prey interactions, though recent work has shown that escape response can also be induced by high temperature. Here, we test the hypothesis that air-breathing fish may use C-starts in the context of gulping air at the surface. Hoplosternum littorale is an air-breathing freshwater catfish found in South America. Field video observations reveal that their air-breathing behaviour consists of air-gulping at the surface, followed by a fast turn which re-directs the fish towards the bottom. Using high-speed video in the laboratory, we compared the kinematics of the turn immediately following air-gulping performed by H. littorale in normoxia with those of mechanically-triggered C-start escape responses and with routine (i.e. spontaneous) turns. Our results show that air-breathing events overlap considerably with escape responses with a large stage 1 angle in terms of turning rates, distance covered and the relationship between these rates. Therefore, these two behaviours can be considered kinematically comparable, suggesting that air-breathing in this species is followed by escape-like C-start motions, presumably to minimise time at the surface and exposure to avian predators. These findings show that C-starts can occur in a variety of contexts in which fish may need to get away from areas of potential danger. PMID:25527644

  15. High-Throughput Sequencing Identifies MicroRNAs from Posterior Intestine of Loach (Misgurnus anguillicaudatus) and Their Response to Intestinal Air-Breathing Inhibition

    PubMed Central

    Huang, Songqian; Cao, Xiaojuan; Tian, Xianchang; Wang, Weimin

    2016-01-01

    MicroRNAs (miRNAs) exert important roles in animal growth, immunity, and development, and regulate gene expression at the post-transcriptional level. Knowledges about the diversities of miRNAs and their roles in accessory air-breathing organs (ABOs) of fish remain unknown. In this work, we used high-throughput sequencing to identify known and novel miRNAs from the posterior intestine, an important ABO, in loach (Misgurnus anguillicaudatus) under normal and intestinal air-breathing inhibited conditions. A total of 204 known and 84 novel miRNAs were identified, while 47 miRNAs were differentially expressed between the two small RNA libraries (i.e. between the normal and intestinal air-breathing inhibited group). Potential miRNA target genes were predicted by combining our transcriptome data of the posterior intestine of the loach under the same conditions, and then annotated using COG, GO, KEGG, Swissprot and Nr databases. The regulatory networks of miRNAs and their target genes were analyzed. The abundances of nine known miRNAs were validated by qRT-PCR. The relative expression profiles of six known miRNAs and their eight corresponding target genes, and two novel potential miRNAs were also detected. Histological characteristics of the posterior intestines in both normal and air-breathing inhibited group were further analyzed. This study contributes to our understanding on the functions and molecular regulatory mechanisms of miRNAs in accessory air-breathing organs of fish. PMID:26872032

  16. Materials Advance Chemical Propulsion Technology

    NASA Technical Reports Server (NTRS)

    2012-01-01

    In the future, the Planetary Science Division of NASA's Science Mission Directorate hopes to use better-performing and lower-cost propulsion systems to send rovers, probes, and observers to places like Mars, Jupiter, and Saturn. For such purposes, a new propulsion technology called the Advanced Materials Bipropellant Rocket (AMBR) was developed under NASA's In-Space Propulsion Technology (ISPT) project, located at Glenn Research Center. As an advanced chemical propulsion system, AMBR uses nitrogen tetroxide oxidizer and hydrazine fuel to propel a spacecraft. Based on current research and development efforts, the technology shows great promise for increasing engine operation and engine lifespan, as well as lowering manufacturing costs. In developing AMBR, ISPT has several goals: to decrease the time it takes for a spacecraft to travel to its destination, reduce the cost of making the propulsion system, and lessen the weight of the propulsion system. If goals like these are met, it could result in greater capabilities for in-space science investigations. For example, if the amount (and weight) of propellant required on a spacecraft is reduced, more scientific instruments (and weight) could be added to the spacecraft. To achieve AMBR s maximum potential performance, the engine needed to be capable of operating at extremely high temperatures and pressure. To this end, ISPT required engine chambers made of iridium-coated rhenium (strong, high-temperature metallic elements) that allowed operation at temperatures close to 4,000 F. In addition, ISPT needed an advanced manufacturing technique for better coating methods to increase the strength of the engine chamber without increasing the costs of fabricating the chamber.

  17. Center for Advanced Space Propulsion Second Annual Technical Symposium Proceedings

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The proceedings for the Center for Advanced Space Propulsion Second Annual Technical Symposium are divided as follows: Chemical Propulsion, CFD; Space Propulsion; Electric Propulsion; Artificial Intelligence; Low-G Fluid Management; and Rocket Engine Materials.

  18. Workshop on Solar Electric Propulsion

    NASA Technical Reports Server (NTRS)

    Bents, David; Marvin, Dean

    1993-01-01

    A summary of the discussion at the workshop on solar electric propulsion (SEP) is presented. The purpose of ELITE SEP flight experiment is to demonstrate operation of solar array powered electric thrusters for raising spacecraft from parking orbit to higher altitudes, leading to definition of an operational SEP orbit transfer vehicles (OTV) for Air Force missions. Many of the problems or potential problems that may be associated with SEP are not well understood nor clearly identified, and system level phenomena such as interaction of thruster plume with the solar arrays cannot be simulated in a ground test. Therefore, an end-to-end system flight test is required to demonstrate solar electric propulsion.

  19. TOPS attitude propulsion subsystem technology

    NASA Technical Reports Server (NTRS)

    Moynihan, P. I.

    1971-01-01

    The thermoelectric outer-planet spacecraft (TOPS) attitude propulsion subsystem effort is summarized. It includes the tradeoff rationale that went into the selection of anhydrous hydrazine as the propellant, and a brief description of three types of 0.445-N (100-mlbf) thrusters that were purchased for in-house evaluation. A discussion is also included of the 0.2224-N (50-mlbf)-developed thrusters and their integration with a portable, completely enclosed, propulsion module that was designed and developed to support the TOPS single-axis attitude control tests in the celestarium.

  20. CFD Techniques for Propulsion Applications

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The symposium was composed of the following sessions: turbomachinery computations and validations; flow in ducts, intakes, and nozzles; and reacting flows. Forty papers were presented, and they covered full 3-D code validation and numerical techniques; multidimensional reacting flow; and unsteady viscous flow for the entire spectrum of propulsion system components. The capabilities of the various numerical techniques were assessed and significant new developments were identified. The technical evaluation spells out where progress has been made and concludes that the present state of the art has almost reached the level necessary to tackle the comprehensive topic of computational fluid dynamics (CFD) validation for propulsion.

  1. Nuclear Propulsion Project Workshop summary

    NASA Technical Reports Server (NTRS)

    Miller, Thomas J.; Clark, John S.; Barnett, John W.

    1991-01-01

    NASA-Lewis has undertaken the planning and coordination of a joint NASA/DOE/DOD Nuclear Propulsion Project which will investigate both nuclear electric and nuclear thermal concepts. The three-agency team has been tasked with the development of an Interagency Agreement and Memorandum of Understanding, as well as the drafting of a statement as to astronaut crew guidelines and values, the assessment of human-rating requirements, the development of an interagency safety and environmental assessment plan, and the development of test facility requirements. Attention is to be given to the role of SP-100 for nuclear-electric propulsion applications.

  2. Z-Pinch Fusion Propulsion

    NASA Technical Reports Server (NTRS)

    Miernik, Janie

    2011-01-01

    Fusion-based nuclear propulsion has the potential to enable fast interplanetary transportation. Shorter trips are better for humans in the harmful radiation environment of deep space. Nuclear propulsion and power plants can enable high Ispand payload mass fractions because they require less fuel mass. Fusion energy research has characterized the Z-Pinch dense plasma focus method. (1) Lightning is form of pinched plasma electrical discharge phenomena. (2) Wire array Z-Pinch experiments are commonly studied and nuclear power plant configurations have been proposed. (3) Used in the field of Nuclear Weapons Effects (NWE) testing in the defense industry, nuclear weapon x-rays are simulated through Z-Pinch phenomena.

  3. Electrolysis Propulsion Provides High-Performance, Inexpensive, Clean Spacecraft Propulsion

    NASA Technical Reports Server (NTRS)

    deGroot, Wim A.

    1999-01-01

    An electrolysis propulsion system consumes electrical energy to decompose water into hydrogen and oxygen. These gases are stored in separate tanks and used when needed in gaseous bipropellant thrusters for spacecraft propulsion. The propellant and combustion products are clean and nontoxic. As a result, costs associated with testing, handling, and launching can be an order of magnitude lower than for conventional propulsion systems, making electrolysis a cost-effective alternative to state-of-the-art systems. The electrical conversion efficiency is high (>85 percent), and maximum thrust-to-power ratios of 0.2 newtons per kilowatt (N/kW), a 370-sec specific impulse, can be obtained. A further advantage of the water rocket is its dual-mode potential. For relatively high thrust applications, the system can be used as a bipropellant engine. For low thrust levels and/or small impulse bit requirements, cold gas oxygen can be used alone. An added innovation is that the same hardware, with modest modifications, can be converted into an energy-storage and power-generation fuel cell, reducing the spacecraft power and propulsion system weight by an order of magnitude.

  4. In-Space Propulsion Technology Program Solar Electric Propulsion Technologies

    NASA Technical Reports Server (NTRS)

    Dankanich, John W.

    2006-01-01

    NASA's In-space Propulsion (ISP) Technology Project is developing new propulsion technologies that can enable or enhance near and mid-term NASA science missions. The Solar Electric Propulsion (SEP) technology area has been investing in NASA s Evolutionary Xenon Thruster (NEXT), the High Voltage Hall Accelerator (HiVHAC), lightweight reliable feed systems, wear testing, and thruster modeling. These investments are specifically targeted to increase planetary science payload capability, expand the envelope of planetary science destinations, and significantly reduce the travel times, risk, and cost of NASA planetary science missions. Status and expected capabilities of the SEP technologies are reviewed in this presentation. The SEP technology area supports numerous mission studies and architecture analyses to determine which investments will give the greatest benefit to science missions. Both the NEXT and HiVHAC thrusters have modified their nominal throttle tables to better utilize diminished solar array power on outbound missions. A new life extension mechanism has been implemented on HiVHAC to increase the throughput capability on low-power systems to meet the needs of cost-capped missions. Lower complexity, more reliable feed system components common to all electric propulsion (EP) systems are being developed. ISP has also leveraged commercial investments to further validate new ion and hall thruster technologies and to potentially lower EP mission costs.

  5. Propulsion Risk Reduction Activities for Nontoxic Cryogenic Propulsion

    NASA Technical Reports Server (NTRS)

    Smith, Timothy D.; Klem, Mark D.; Fisher, Kenneth L.

    2010-01-01

    The Propulsion and Cryogenics Advanced Development (PCAD) Project s primary objective is to develop propulsion system technologies for nontoxic or "green" propellants. The PCAD project focuses on the development of nontoxic propulsion technologies needed to provide necessary data and relevant experience to support informed decisions on implementation of nontoxic propellants for space missions. Implementation of nontoxic propellants in high performance propulsion systems offers NASA an opportunity to consider other options than current hypergolic propellants. The PCAD Project is emphasizing technology efforts in reaction control system (RCS) thruster designs, ascent main engines (AME), and descent main engines (DME). PCAD has a series of tasks and contracts to conduct risk reduction and/or retirement activities to demonstrate that nontoxic cryogenic propellants can be a feasible option for space missions. Work has focused on 1) reducing the risk of liquid oxygen/liquid methane ignition, demonstrating the key enabling technologies, and validating performance levels for reaction control engines for use on descent and ascent stages; 2) demonstrating the key enabling technologies and validating performance levels for liquid oxygen/liquid methane ascent engines; and 3) demonstrating the key enabling technologies and validating performance levels for deep throttling liquid oxygen/liquid hydrogen descent engines. The progress of these risk reduction and/or retirement activities will be presented.

  6. Propulsion Risk Reduction Activities for Non-Toxic Cryogenic Propulsion

    NASA Technical Reports Server (NTRS)

    Smith, Timothy D.; Klem, Mark D.; Fisher, Kenneth

    2010-01-01

    The Propulsion and Cryogenics Advanced Development (PCAD) Project s primary objective is to develop propulsion system technologies for non-toxic or "green" propellants. The PCAD project focuses on the development of non-toxic propulsion technologies needed to provide necessary data and relevant experience to support informed decisions on implementation of non-toxic propellants for space missions. Implementation of non-toxic propellants in high performance propulsion systems offers NASA an opportunity to consider other options than current hypergolic propellants. The PCAD Project is emphasizing technology efforts in reaction control system (RCS) thruster designs, ascent main engines (AME), and descent main engines (DME). PCAD has a series of tasks and contracts to conduct risk reduction and/or retirement activities to demonstrate that non-toxic cryogenic propellants can be a feasible option for space missions. Work has focused on 1) reducing the risk of liquid oxygen/liquid methane ignition, demonstrating the key enabling technologies, and validating performance levels for reaction control engines for use on descent and ascent stages; 2) demonstrating the key enabling technologies and validating performance levels for liquid oxygen/liquid methane ascent engines; and 3) demonstrating the key enabling technologies and validating performance levels for deep throttling liquid oxygen/liquid hydrogen descent engines. The progress of these risk reduction and/or retirement activities will be presented.

  7. Vertical Takeoff and Landing (VTOL) propulsion technology

    NASA Technical Reports Server (NTRS)

    Ciepluch, C. C.; Abbott, J. M.; Moore, R. D.; Sellers, J. F.

    1979-01-01

    Propulsion problems and advanced technology requirements of VTOL aircraft are discussed. Specific topics covered include inlets with high angle of attack capability, rapid thrust modulation fans, and propulsion-system/aircraft-control integration.

  8. Nuclear propulsion technology advanced fuels technology

    NASA Technical Reports Server (NTRS)

    Stark, Walter A., Jr.

    1993-01-01

    Viewgraphs on advanced fuels technology are presented. Topics covered include: nuclear thermal propulsion reactor and fuel requirements; propulsion efficiency and temperature; uranium fuel compounds; melting point experiments; fabrication techniques; and sintered microspheres.

  9. Nuclear Propulsion Technical Interchange Meeting, volume 2

    NASA Technical Reports Server (NTRS)

    1993-01-01

    The purpose of the meeting was to review the work performed in fiscal year 1992 in the areas of nuclear thermal and nuclear electric propulsion technology development. These proceedings are an accumulation of the presentations provided at the meeting along with annotations provided by authors. The proceedings cover system concepts, technology development, and system modeling for nuclear thermal propulsion (NTP) and nuclear electric propulsion (NEP). The test facilities required for the development of the nuclear propulsion systems are also discussed.

  10. Test facilities for high power electric propulsion

    NASA Technical Reports Server (NTRS)

    Sovey, James S.; Vetrone, Robert H.; Grisnik, Stanley P.; Myers, Roger M.; Parkes, James E.

    1991-01-01

    Electric propulsion has applications for orbit raising, maneuvering of large space systems, and interplanetary missions. These missions involve propulsion power levels from tenths to tens of megawatts, depending upon the application. General facility requirements for testing high power electric propulsion at the component and thrust systems level are defined. The characteristics and pumping capabilities of many large vacuum chambers in the United States are reviewed and compared with the requirements for high power electric propulsion testing.

  11. The Future of Spacecraft Nuclear Propulsion

    NASA Astrophysics Data System (ADS)

    Jansen, F.

    2014-06-01

    This paper summarizes the advantages of space nuclear power and propulsion systems. It describes the actual status of international power level dependent spacecraft nuclear propulsion missions, especially the high power EU-Russian MEGAHIT study including the Russian Megawatt-Class Nuclear Power Propulsion System, the NASA GRC project and the low and medium power EU DiPoP study. Space nuclear propulsion based mission scenarios of these studies are sketched as well.

  12. Advanced NSTS propulsion system verification study

    NASA Technical Reports Server (NTRS)

    Wood, Charles

    1989-01-01

    The merits of propulsion system development testing are discussed. The existing data base of technical reports and specialists is utilized in this investigation. The study encompassed a review of all available test reports of propulsion system development testing for the Saturn stages, the Titan stages, and the Space Shuttle main propulsion system. The knowledge on propulsion system development and system testing available from specialists and managers was also 'tapped' for inclusion.

  13. Comparison of Mars Aircraft Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Colozza, Anthony J.

    2003-01-01

    The propulsion system is a critical aspect of the performance and feasibility of a Mars aircraft. Propulsion system mass and performance greatly influence the aircraft s design and mission capabilities. Various propulsion systems were analyzed to estimate the system mass necessary for producing 35N of thrust within the Mars environment. Three main categories of propulsion systems were considered: electric systems, combustion engine systems and rocket systems. Also, the system masses were compared for mission durations of 1, 2, and 4 h.

  14. [Masquerading bundle branch block].

    PubMed

    Kukla, Piotr; Baranchuk, Adrian; Jastrzębski, Marek; Bryniarski, Leszek

    2014-01-01

    We here describe a surface 12-lead electrocardiogram (ECG) of a 72-year-old female with a prior history of breast cancer and chemotherapy-induced cardiomyopathy. An echocardiogram revealed left ventricular dysfunction, ejection fraction of 23%, with mild enlarged left ventricle. The 12-lead ECG showed atrial fibrillation with a mean heart rate of about 100 bpm, QRS duration 160 ms, QT interval 400 ms, right bundle branch block (RBBB) and left anterior fascicular block (LAFB). The combination of RBBB features in the precordial leads and LAFB features in the limb leads is known as ''masquerading bundle branch block''. In most cases of RBBB and LAFB, the QRS axis deviation is located between - 80 to -120 degrees. Rarely, when predominant left ventricular forces are present, the QRS axis deviation is near about -90 degrees, turning the pattern into an atypical form. In a situation of RBBB associated with LAFB, the S wave can be absent or very small in lead I. Such a situation is the result of not only purely LAFB but also with left ventricular hypertrophy and/or focal block due to scar (extensive anterior myocardial infarction) or fibrosis (cardiomyopathy). Sometimes, this specific ECG pattern is mistaken for LBBB. RBBB with LAFB may imitate LBBB either in the limb leads (known as 'standard masquerading' - absence of S wave in lead I), or in the precordial leads (called 'precordial masquerading' - absence of S wave in leads V₅ and V₆). Our ECG showed both these types of masquerading bundle branch block - absence of S wave in lead I and in leads V₅ and V₆. PMID:24469750

  15. Thermal Energy Conversion Branch

    NASA Technical Reports Server (NTRS)

    Bielozer, Matthew C.; Schreiber, Jeffrey, G.; Wilson, Scott D.

    2004-01-01

    The Thermal Energy Conversion Branch (5490) leads the way in designing, conducting, and implementing research for the newest thermal systems used in space applications at the NASA Glenn Research Center. Specifically some of the most advanced technologies developed in this branch can be broken down into four main areas: Dynamic Power Systems, Primary Solar Concentrators, Secondary Solar Concentrators, and Thermal Management. Work was performed in the Dynamic Power Systems area, specifically the Stirling Engine subdivision. Today, the main focus of the 5490 branch is free-piston Stirling cycle converters, Brayton cycle nuclear reactors, and heat rejection systems for long duration mission spacecraft. All space exploring devices need electricity to operate. In most space applications, heat energy from radioisotopes is converted to electrical power. The Radioisotope Thermoelectric Generator (RTG) already supplies electricity for missions such as the Cassini Spacecraft. The focus of today's Stirling research at GRC is aimed at creating an engine that can replace the RTG. The primary appeal of the Stirling engine is its high system efficiency. Because it is so efficient, the Stirling engine will significantly reduce the plutonium fuel mission requirements compared to the RTG. Stirling is also being considered for missions such as the lunar/Mars bases and rovers. This project has focused largely on Stirling Engines of all types, particularly the fluidyne liquid piston engine. The fluidyne was developed by Colin D. West. This engine uses the same concepts found in any type of Stirling engine, with the exception of missing mechanical components. All the working components are fluid. One goal was to develop and demonstrate a working Stirling Fluidyne Engine at the 2nd Annual International Energy Conversion Engineering Conference in Providence, Rhode Island.

  16. Flight Dynamics Analysis Branch

    NASA Technical Reports Server (NTRS)

    Stengle, Tom; Flores-Amaya, Felipe

    2000-01-01

    This report summarizes the major activities and accomplishments carried out by the Flight Dynamics Analysis Branch (FDAB), Code 572, in support of flight projects and technology development initiatives in fiscal year 2000. The report is intended to serve as a summary of the type of support carried out by the FDAB, as well as a concise reference of key accomplishments and mission experience derived from the various mission support roles. The primary focus of the FDAB is to provide expertise in the disciplines of flight dynamics, spacecraft trajectory, attitude analysis, and attitude determination and control. The FDAB currently provides support for missions and technology development projects involving NASA, government, university, and private industry.

  17. Controls and Health Management Technologies for Intelligent Aerospace Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Garg, Sanjay

    2004-01-01

    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 Technology 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 an Intelligent Engine. The key enabling technologies for an Intelligent Engine are the increased efficiencies of components through active control, advanced diagnostics and prognostics integrated with intelligent engine control to enhance component life, and distributed control with smart sensors and actuators in an adaptive fault tolerant architecture. This paper describes the current activities of the Controls and Dynamics Technology Branch in the areas of active component control and propulsion system intelligent control, and presents some recent analytical and experimental results in these areas.

  18. NASA Propulsion Engineering Research Center, Volume 2

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This is the second volume in the 1994 annual report for the NASA Propulsion Engineering Research Center's Sixth Annual Symposium. This conference covered: (1) Combustors and Nozzles; (2) Turbomachinery Aero- and Hydro-dynamics; (3) On-board Propulsion systems; (4) Advanced Propulsion Applications; (5) Vaporization and Combustion; (6) Heat Transfer and Fluid Mechanics; and (7) Atomization and Sprays.

  19. NASA's In-Space Propulsion Technology Program

    NASA Astrophysics Data System (ADS)

    Johnson, L.; Robinson, J.

    2004-11-01

    NASA's In-Space Propulsion Technology Program is investing in technologies that have the potential to revolutionize the robotic exploration of deep space. For robotic exploration and science missions, increased efficiencies of future propulsion systems are critical to reduce overall life-cycle costs and, in some cases, enable missions previously considered impossible. Continued reliance on conventional chemical propulsion alone will not enable the robust exploration of deep space - the maximum theoretical efficiencies have almost been reached and they are insufficient to meet needs for many ambitious science missions currently being considered. The In-Space Propulsion Technology Program's technology portfolio includes many advanced propulsion systems. From the next generation ion propulsion system operating in the 5 - 10 kW range, to advanced cryogenic propulsion, substantial advances in spacecraft propulsion performance are anticipated. Some of the most promising technologies for achieving these goals use the environment of space itself for energy and propulsion and are generically called, ``propellantless" because they do not require on-board fuel to achieve thrust. Propellantless propulsion technologies include scientific innovations such as solar sails, electrodynamic and momentum transfer tethers, aeroassist, and aerocapture. This paper will provide an overview of both propellantless and propellant-based advanced propulsion technologies, and NASA's plans for advancing them as part of the \\$60M per year In-Space Propulsion Technology Program. Solar sails and aerocapture are candidates for flight validation as early as 2008 in partnership with NASA's New Millennium Program.

  20. A fusion based plasma propulsion system

    NASA Technical Reports Server (NTRS)

    George, J. A.; Anderson, B.; Bryant, D.; Creese, C.; Djordjevic, V.; Peddicord, K. L.

    1987-01-01

    The Fusion Plasma Propulsion System scoping study was performed to investigate the possibilities of a fusion powered plasma propulsion system for space applications. Specifically, it was to be compared against existing electric propulsion concepts for a manned Mars mission. Design parameters consist of 1000 N thrust for 500 days, and the minimum mass possible. This investigation is briefly presented and conclusions drawn.

  1. Applications of nuclear propulsion to Mars missions

    NASA Technical Reports Server (NTRS)

    Rosen, Robert; Reck, Gregory M.; Bennett, Gary L.

    1991-01-01

    The basic features of a piloted mission to Mars is described, and it is shown how nuclear propulsion can improve upon the various performance measures of such a mission. An overview of the history and types of nuclear propulsion in the U.S. is presented. Current planning to develop nuclear propulsion technology for the Space Exploration Initiative is addressed.

  2. Characterization of advanced electric propulsion systems

    NASA Technical Reports Server (NTRS)

    Ray, P. K.

    1982-01-01

    Characteristic parameters of several advanced electric propulsion systems are evaluated and compared. The propulsion systems studied are mass driver, rail gun, argon MPD thruster, hydrogen free radical thruster and mercury electron bombardment ion engine. Overall, ion engines have somewhat better characteristics as compared to the other electric propulsion systems.

  3. Some Interplanetary Missions Using IEC Fusion Propulsion

    NASA Technical Reports Server (NTRS)

    Hanson, John M.; Brandon, Larry B. (Technical Monitor)

    2001-01-01

    IEC fusion offers the possibility of very efficient space propulsion with substantial thrust, examine human travel to the planets in order to determine the impact this technology could have reduced travel time and reduced fuel mass, travel via IEC propulsion is from earth orbit to another planetary orbit. Propulsion to a planet's or moon's surface assumed separate.

  4. Multi-Thruster Propulsion Apparatus

    NASA Technical Reports Server (NTRS)

    Patterson, Michael J. (Inventor)

    2016-01-01

    An electric propulsion machine includes an ion thruster having a discharge chamber housing a large surface area anode. The ion thruster includes flat annular ion optics with a small span to gap ratio. Optionally, at least a second thruster may be disposed radially offset from the ion thruster.

  5. MAP Propulsion System Thermal Design

    NASA Technical Reports Server (NTRS)

    Mosier, Carol L.

    2003-01-01

    The propulsion system of the Microwave Anisotropy Probe (MAP) had stringent requirements that made the thermal design unique. To meet instrument stability requirements the system had to be designed to keep temperatures of all components within acceptable limits without heater cycling. Although the spacecraft remains at a fixed 22 sun angle at L2, the variations in solar constant, property degradation, and bus voltage range all significantly affect the temperature. Large portions of the fuel lines are external to the structure and all components are mounted to non-conductive composite structure. These two facts made the sensitivity to the MLI effective emissivity and bus temperature very high. Approximately two years prior to launch the propulsion system was redesigned to meet MAP requirements. The new design utilized hardware that was already installed in order to meet schedule constraints. The spacecraft design and the thermal requirements were changed to compensate for inadequacies of the existing hardware. The propulsion system consists of fuel lines, fill and drain lines/valve, eight thrusters, a HXCM, and a propulsion tank. A voltage regulator was added to keep critical components within limits. Software was developed to control the operational heaters. Trim resistors were put in series with each operational heater circuits and the tank survival heater. A highly sophisticated test program, which included real time model correlation, was developed to determine trim resistors sizes. These trim resistors were installed during a chamber break and verified during thermal balance testing.

  6. Innovative electric propulsion thruster modeling

    NASA Technical Reports Server (NTRS)

    Frisbee, Robert H.

    1993-01-01

    The objective of this program is to model and evaluate advanced nuclear electric propulsion (NEP) system concepts as an aid to the performance of NEP mission benefits studies. The two primary goals are as follows: (1) provide scaling relationships for mass, power, and efficiency, as functions of Isp, propellant type, and other important quantities. The discussion is presented in vugraph form.

  7. In-space nuclear propulsion

    NASA Astrophysics Data System (ADS)

    Bruno, C.; Dujarric, C.

    2013-02-01

    The past and the recent status of nuclear propulsion (NP) for application to space mission is presented. The case for using NP in manned space missions is made based on fundamental physics and on the necessity to ensure safe radiation doses to future astronauts. In fact, the presence of solar and galactic-cosmic radiation poses substantial risks to crews traveling for months in a row to destinations such as asteroids and Mars. Since passive or active shields would be massive to protect against the more energetic part of the radiation energy spectrum, the only alternative is to reduce dose by traveling faster. Hence the importance of propulsion systems with much higher specific impulse than that of current chemical systems, and thus the use of nuclear propulsion. Nuclear-thermal and nuclear-electric propulsions are then discussed in view of their potential application to missions now in the preliminary planning stage by space agencies and industries and being considered by the ISECG international panel. In this context, recent ideas for future use of the ISS that may require NP are also presented.

  8. Ultrasonic propulsion of kidney stones

    PubMed Central

    May, Philip C.; Bailey, Michael R.; Harper, Jonathan D.

    2016-01-01

    Purpose of review Ultrasonic propulsion is a novel technique that uses short bursts of focused ultrasonic pulses to reposition stones transcutaneously within the renal collecting system and ureter. The purpose of this review is to discuss the initial testing of effectiveness and safety, directions for refinement of technique and technology, and opinions on clinical application. Recent findings Preclinical studies with a range of probes, interfaces, and outputs have demonstrated feasibility and consistent safety of ultrasonic propulsion with room for increased outputs and refinement toward specific applications. Ultrasonic propulsion was used painlessly and without adverse events to reposition stones in 14 of 15 human study participants without restrictions on patient size, stone size, or stone location. The initial feasibility study showed applicability in a range of clinically relevant situations, including facilitating passage of residual fragments following ureteroscopy or shock wave lithotripsy, moving a large stone at the UPJ with relief of pain, and differentiating large stones from a collection of small fragments. Summary Ultrasonic propulsion shows promise as an office-based system for transcutaneously repositioning kidney stones. Potential applications include facilitating expulsion of residual fragments following ureteroscopy or shock wave lithotripsy, repositioning stones prior to treatment, and repositioning obstructing UPJ stones into the kidney to alleviate acute renal colic. PMID:26845428

  9. Magnetohydrodynamic Propulsion for the Classroom

    NASA Astrophysics Data System (ADS)

    Font, Gabriel I.; Dudley, Scott C.

    2004-10-01

    The cinema industry can sometimes prove to be an ally when searching for material with which to motivate students to learn physics. Consider, for example, the electromagnetic force on a current in the presence of a magnetic field. This phenomenon is at the heart of magnetohydrodynamic (MHD) propulsion systems. A submarine employing this type of propulsion was immortalized in the movie Hunt for Red October. While mentioning this to students certainly gets their attention, it often elicits comments that it is only fiction and not physically possible. Imagine their surprise when a working system is demonstrated! It is neither difficult nor expensive to construct a working system that can be demonstrated in the front of a classroom.2 In addition, all aspects of the engineering hurdles that must be surmounted and myths concerning this "silent propulsion" system are borne out in a simple apparatus. This paper details how to construct an inexpensive MHD propulsion boat that can be demonstrated for students in the classroom.

  10. Novel prescribed performance neural control of a flexible air-breathing hypersonic vehicle with unknown initial errors.

    PubMed

    Bu, Xiangwei; Wu, Xiaoyan; Zhu, Fujing; Huang, Jiaqi; Ma, Zhen; Zhang, Rui

    2015-11-01

    A novel prescribed performance neural controller with unknown initial errors is addressed for the longitudinal dynamic model of a flexible air-breathing hypersonic vehicle (FAHV) subject to parametric uncertainties. Different from traditional prescribed performance control (PPC) requiring that the initial errors have to be known accurately, this paper investigates the tracking control without accurate initial errors via exploiting a new performance function. A combined neural back-stepping and minimal learning parameter (MLP) technology is employed for exploring a prescribed performance controller that provides robust tracking of velocity and altitude reference trajectories. The highlight is that the transient performance of velocity and altitude tracking errors is satisfactory and the computational load of neural approximation is low. Finally, numerical simulation results from a nonlinear FAHV model demonstrate the efficacy of the proposed strategy. PMID:26456727

  11. Critical importance of humidification of the anode in miniature air-breathing polymer electrolyte membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Hamel, Simon; Fréchette, Luc G.

    2011-08-01

    Although water management at the cathode is known to be critical in miniature polymer electrolyte membrane fuel cells (mPEMFCs), this study shows that control of water transport towards the anode is a determining factor to increase air-breathing mPEMFC performances. An analytical 1D model is developed to capture the water transport and water content profile in the membrane. It shows that drying at the anode and flooding at the cathode can happen simultaneously, mainly due to dominant electro-osmotic drag at low cell temperatures. Experimental results demonstrate that injecting water at the anode, at a rate of 3 times the amount produced at the cathode, increases the cell performances at high current densities. By this method, the limiting current and maximum power densities have been raised by 100% and 30% respectively.

  12. Development of gas exchange and ion regulation in two species of air-breathing fish, Betta splendens and Macropodus opercularis.

    PubMed

    Huang, Chun-Yen; Lin, Cheng-Huang; Lin, Hui-Chen

    2015-07-01

    Aquatic air-breathing anabantoids, a group of fish species characterized by the presence of a labyrinth organ and some gills, exhibit morphological variations. This study aimed to examine whether unequal gill growth begins during the early stages and described the sequence of the early gill developmental events in Betta splendens and Macropodus opercularis. To determine when the ion regulatory and gas exchange abilities first appear in the gills, mitochondria-rich cells (MRCs) and neuroepithelial cells (NECs) were examined in young B. splendens. To evaluate the relative importance of the gills and the labyrinth organ under different levels of oxygen uptake stress, the levels of carbonic anhydrase II (CAII) and Na(+)/K(+)-ATPase (NKA) protein expressions in 2 gills and the labyrinth organ were examined in M. opercularis. We found that the first 3 gills developed earlier than the 4th gill in both species, an indication that the morphological variation begins early in life. In B. splendens, the MRCs and NECs clearly appeared in the first 3 gills at 4 dph and were first found in the 4th gill until 11 dph. The oxygen-sensing ability of the gills was concordant with the ionoregulatory function. In M. opercularis, the hypoxic group had a significantly higher air-breathing frequency. CAII protein expression was higher in the labyrinth organ in the hypoxic group. The gills exhibited increased NKA protein expression in the hypoxic and restricted groups, respectively. Functional plasticity in CAII and NKA protein expressions was found between the gills and the labyrinth organ in adult M. opercularis. PMID:25783787

  13. Feasibility study of a nonequilibrium MHD accelerator concept for hypersonic propulsion ground testing

    SciTech Connect

    Lee, Ying-Ming; Simmons, G.A.; Nelson, G.L.

    1995-12-31

    A National Aeronautics and Space Administration (NASA) funded research study to evaluate the feasibility of using magnetohydrodynamic (MHD) body force accelerators to produce true air simulation for hypersonic propulsion ground testing is discussed in this paper. Testing over the airbreathing portion of a transatmospheric vehicle (TAV) hypersonic flight regime will require high quality air simulation for actual flight conditions behind a bow shock wave (forebody, pre-inlet region) for flight velocities up to Mach 16 and perhaps beyond. Material limits and chemical dissociation at high temperature limit the simulated flight Mach numbers in conventional facilities to less than Mach 12 for continuous and semi-continuous testing and less than Mach 7 for applications requiring true air chemistry. By adding kinetic energy directly to the flow, MHD accelerators avoid the high temperatures and pressures required in the reservoir region of conventional expansion facilities, allowing MHD to produce true flight conditions in flight regimes impossible with conventional facilities. The present study is intended to resolve some of the critical technical issues related to the operation of MHD at high pressure. Funding has been provided only for the first phase of a three to four year feasibility study that would culminate in the demonstration of MHD acceleration under conditions required to produce true flight conditions behind a bow shock wave to flight Mach numbers of 16 or greater. MHD critical issues and a program plan to resolve these are discussed.

  14. Propulsion Systems Integration for a `Tractor Beam' Mercury Lightcraft: Liftoff Engine

    NASA Astrophysics Data System (ADS)

    Myrabo, L. N.

    2003-05-01

    Described herein is the concept and propulsion systems integration for a revolutionary beam-propelled shuttle called the ``Mercury'' lightcraft - emphasizing the liftoff engine mode. This one-person, ultra-energetic vehicle is designed to ride `tractor beams' into space, transmitted from a future network of satellite solar power stations. The objective is to create a safe, very low cost (e.g., 1000X below chemical rockets) space transportation system for human life, one that is completely `green' and independent of Earth's limited fossil fuel reserves. The lightcraft's airbreathing combined-cycle engine operates in a rotary pulsed detonation mode PDE for lift-offs and landings; at hypersonic speeds it transitions into a magnetohydrodynamic (MHD) slipstream accelerator mode. For the latter, the transatmospheric flight path is momentarily transformed into an extremely long, electromagnetic ``mass-driver'' channel with an effective `fuel' specific impulse in the range of 6000 to 16,000 seconds. These future single-stage-to-orbit, highly-reusuable vehicles will ride ``Highways of Light,'' accelerating at 3 Gs into space, with their throttles just barely beyond `idle' power.

  15. Advanced technology for future space propulsion systems

    NASA Technical Reports Server (NTRS)

    Diehl, Larry A.

    1989-01-01

    The NASA Project Pathfinder contains programs to provide technologies for future transfer vehicles including those powered by both advanced chemical and electric propulsion rockets. This paper discusses the Chemical Transfer Propulsion and Cargo Vehicle Propulsion elements of Pathfinder. The program requirements and goals for both elements are discussed, and technical activities which are planned or underway are summarized. Recent progress in programs which support or proceed the Pathfinder activities is detailed. In particular, the NASA Program for Advanced Orbital Transfer Vehicle Propulsion, which acted as the precursor for the Chemical Transfer Propulsion element of Pathfinder is summarized.

  16. Assessment of flying-quality criteria for air-breathing aerospacecraft

    NASA Technical Reports Server (NTRS)

    Mcruer, Duane T.; Myers, Thomas T.; Hoh, Roger H.; Ashkenas, Irving L.; Johnston, Donald E.

    1992-01-01

    A study of flying quality requirements for air breathing aerospacecraft gives special emphasis to the unusual operational requirements and characteristics of these aircraft, including operation at hypersonic speed. The report considers distinguishing characteristics of these vehicles, including dynamic deficiencies and their implications for control. Particular emphasis is given to the interaction of the airframe and propulsion system, and the requirements for dynamic systems integration. Past operational missions are reviewed to define tasks and maneuvers to be considered for this class of aircraft. Areas of special concern with respect to vehicle dynamics and control are identified. Experience with the space shuttle orbiter is reviewed with respect to flight control system mechanization and flight experience in approach and landing flying qualities for the National Aerospace Plane (NASP).

  17. Time-resolved imaging for the dynamic study of ablative laser propulsion

    NASA Astrophysics Data System (ADS)

    Lin, Jun

    Time-resolved imaging techniques have been developed and used for a study of plasma dynamics in Ablative Laser Propulsion (ALP), an advanced propulsion technique utilizing the momentum of laser-ablated solid propellants for rocket thrust. We used a gated Intensified Charge Coupled Device camera to record light emission from laser-induced plasma. The plasma was ignited by 100-ps wide laser pulses, of energy 35 mJ at 532 nm wavelength. The required algorithms for processing 2-D digital images of the plasma and deriving the plasma edge velocities were also developed. The 2-D angular distribution functions for both plasma velocity and emission intensity were deduced from these measurements for the first time. The fitting functions for observed angular distributions were derived for a wide range of elements, such as C (graphite), Al, Si, Cu, Fe, Zn, Sn and Pb. Results show that the specific impulses (I sp) vary between 2.6 x 103 s (carbon) and 1.2 x 103 s (zinc), which are in excellent agreement with previously conducted Force Measurements. We also developed a digital video imaging (DVI) technique to study the dynamics of a ballistic pendulum driven by TEA CO2 laser pulses. The pulses had 200 ns pulsewidth and 10.6 J energy at 10.6 mum wavelength. The experiment using the DVI technique in the range of pressures from 3.5 mTorr to 1 atmosphere has been developed for the first time. Coupling coefficients (Cm) and mass removal rates as functions of pressure were deduced from these measurements. The technique allowed the addressing of the partition of the energy and momentum between air breakdown and target ablation. The study was performed on Aluminum targets. The partition functions show a sharp transition region between 1.0 and 10 Torr, where the momentum and energy imparted to the target via ablation appear comparable to those due to air breakdown. Our observations show that currently developing air-breathing laser-propulsion schemes would hardly support launching

  18. The Direction of Fluid Dynamics for Liquid Propulsion at NASA Marshall Space Flight Center

    NASA Technical Reports Server (NTRS)

    Griffin, Lisa W.

    2012-01-01

    The Fluid Dynamics Branch's (ER42) at MSFC mission is to support NASA and other customers with discipline expertise to enable successful accomplishment of program/project goals. The branch is responsible for all aspects of the discipline of fluid dynamics, analysis and testing, applied to propulsion or propulsion-induced loads and environments, which includes the propellant delivery system, combustion devices, coupled systems, and launch and separation events. ER42 supports projects from design through development, and into anomaly and failure investigations. ER42 is committed to continually improving the state-of-its-practice to provide accurate, effective, and timely fluid dynamics assessments and in extending the state-of-the-art of the discipline.

  19. Methods and Technologies Branch (MTB)

    Cancer.gov

    The Methods and Technologies Branch focuses on methods to address epidemiologic data collection, study design and analysis, and to modify technological approaches to better understand cancer susceptibility.

  20. Branches in the Everett interpretation

    NASA Astrophysics Data System (ADS)

    Cunningham, Arthur J.

    2014-05-01

    Hugh Everett III describes a quantum measurement as resulting in the "branching" of the quantum state of observer and measured system, with all possible measurement outcomes represented by the ensuing branches of the total quantum state. But Everett does not specify a general rule for decomposing a quantum state into branches, and commentators have long puzzled over how, and even whether, to regard Everett's notion of branching states as physically meaningful. It is common today to appeal to decoherence considerations as a way of giving physical content to the Everettian notion of branches, but these appeals to decoherence are often regarded as considerations foreign to Everett's own approach. This paper contends that this assessment is only half right: though he does not invoke environmental decoherence, Everett does appeal to decoherence considerations, broadly understood, in his treatment of measurement. Careful consideration of his idealized models of measurement, and of the significance he ascribes to the branching of states corresponding to definite measurement outcomes, reveals that his notion of branching refers to a special physical characteristic of elements of a particular decomposition, namely the absence of interference between these component states as a result of the particular dynamics governing the evolution of the system. Characterizations of branching that appeal to the results of modern decoherence theory should therefore be regarded as a natural development of Everett's own physically meaningful conception of branching.

  1. The control of branching morphogenesis

    PubMed Central

    Iber, Dagmar; Menshykau, Denis

    2013-01-01

    Many organs of higher organisms are heavily branched structures and arise by an apparently similar process of branching morphogenesis. Yet the regulatory components and local interactions that have been identified differ greatly in these organs. It is an open question whether the regulatory processes work according to a common principle and how far physical and geometrical constraints determine the branching process. Here, we review the known regulatory factors and physical constraints in lung, kidney, pancreas, prostate, mammary gland and salivary gland branching morphogenesis, and describe the models that have been formulated to analyse their impacts. PMID:24004663

  2. Development and application of high-temperature sensors and electronics for propulsion applications

    NASA Astrophysics Data System (ADS)

    Hunter, Gary W.; Wrbanek, John D.; Okojie, Robert S.; Neudeck, Philip G.; Fralick, Gustave C.; Chen, Liangyu; Xu, Jennifer; Beheim, Glenn M.

    2006-05-01

    High temperature sensors and electronics are necessary for a number of aerospace propulsion applications. The Sensors and Electronics Branch at NASA Glenn Research Center (NASA GRC) has been involved in the design, fabrication, and application of a range of sensors and electronics that have use in high temperature, harsh environment propulsion environments. The emphasis is on developing advanced capabilities for measurement and control of aeropropulsion systems as well as monitoring the safety of those systems using Micro/Nano technologies. Specific areas of work include SiC based electronic devices and sensors; thin film thermocouples, strain gauges, and heat flux gauges; chemical sensors; as well as integrated and multifunctional sensor systems. Each sensor type has its own technical challenges related to integration and reliability in a given application. These activities have a common goal of improving the awareness of the state of the propulsion system and moving towards the realization of intelligent engines. This paper will give an overview of the broad range of sensor-related development activities on-going in the NASA GRC Sensors and Electronics Branch as well as their current and potential use in propulsion systems.

  3. Laser Ablation Propulsion A Study

    NASA Astrophysics Data System (ADS)

    Irfan, Sayed A.; Ugalatad, Akshata C.

    Laser Ablation Propulsion (LAP) will serve as an alternative propulsion system for development of microthrusters. The principle of LAP is that when a laser (pulsed or continuous wave) with sufficient energy (more than the vaporization threshold energy of material) is incident on material, ablation or vaporization takes place which leads to the generation of plasma. The generated plasma has the property to move away from the material hence pressure is generated which leads to the generation of thrust. Nowadays nano satellites are very common in different space and defence applications. It is important to build micro thruster which are useful for orienting and re-positioning small aircraft (like nano satellites) above the atmosphere. modelling of LAP using MATLAB and Mathematica. Schematic is made for the suitable optical configuration of LAP. Practical experiments with shadowgraphy and self emission techniques and the results obtained are analysed taking poly (vinyl-chloride) (PVC) as propellant to study the

  4. Laser Diagnostics for Spacecraft Propulsion

    NASA Astrophysics Data System (ADS)

    MacDonald-Tenenbaum, Natalia

    2015-09-01

    Over the past several decades, a variety of laser diagnostic techniques have been developed and applied to diagnose spacecraft propulsion devices. Laser diagnostics are inherently non-intrusive, and provide the opportunity to probe properties such as temperature, concentration or number density of plume species, and plume velocities in the harsh environments of combustion and plasma discharges. This presentation provides an overview of laser diagnostic capabilities for spacecraft propulsion devices such as small monopropellant thrusters, arcjets, ion engines and Hall thrusters. Particular emphasis is placed on recent developments for time-resolved ion velocity measurements in Hall thruster plumes. Results are presented for one such diagnostic method, a time-synchronized CW-laser induced fluorescence (LIF) technique based on a sample hold scheme. This method is capable of correlating measured fluorescence excitation lineshapes with high frequency current fluctuations in the plasma discharge of a Hall thruster and is tolerant of natural drifting in the current oscillation frequency.

  5. Attitude propulsion technology for TOPS

    NASA Technical Reports Server (NTRS)

    Moynihan, P. I.

    1972-01-01

    The thermoelectric outer planet spacecraft (TOPS) attitude propulsion subsystem (APS) effort is discussed. It includes the tradeoff rationale that went into the selection of an anhydrous hydrazine baseline system, followed by a discussion of the 0.22 N thruster and its integration into a portable, self-contained propulsion module that was designed, developed, and man rated to support the TOPS single-axis attitude control tests. The results of a cold-start feasibility demonstration with a modified thruster are presented. A description of three types of 0.44 thrusters that were procured for in-house evaluation is included along with the results of the test program. This is followed by a description of the APS feed system components, their evaluations, and a discussion of an evaluation of elastomeric material for valve seat seals. A list of new technology items which will be of value for application to future systems of this type is included.

  6. OTV propulsion tecnology programmatic overview

    NASA Astrophysics Data System (ADS)

    Cooper, L. P.

    1984-04-01

    An advanced orbit transfer vehicles (OTV) which will be an integral part of the national space transportation system to carry men and cargo between low Earth orbit and geosynchronous orbit will perform planetary transfers and deliver large acceleration limited space structures to high Earth orbits is reviewed. The establishment of an advanced propulsion technology base for an OTV for the mid 1990's is outlined. The program supports technology for three unique engine concepts. Work is conducted to generic technologies which benefit all three concepts and specific technology which benefits only one of the concepts. Concept and technology definitions to identify propulsion innovations, and subcomponent research to explore and validate their potential benefits are included.

  7. OTV propulsion tecnology programmatic overview

    NASA Technical Reports Server (NTRS)

    Cooper, L. P.

    1984-01-01

    An advanced orbit transfer vehicles (OTV) which will be an integral part of the national space transportation system to carry men and cargo between low Earth orbit and geosynchronous orbit will perform planetary transfers and deliver large acceleration limited space structures to high Earth orbits is reviewed. The establishment of an advanced propulsion technology base for an OTV for the mid 1990's is outlined. The program supports technology for three unique engine concepts. Work is conducted to generic technologies which benefit all three concepts and specific technology which benefits only one of the concepts. Concept and technology definitions to identify propulsion innovations, and subcomponent research to explore and validate their potential benefits are included.

  8. Planetary explorer liquid propulsion study

    NASA Technical Reports Server (NTRS)

    Mckevitt, F. X.; Eggers, R. F.; Bolz, C. W.

    1971-01-01

    An analytical evaluation of several candidate monopropellant hydrazine propulsion system approaches is conducted in order to define the most suitable configuration for the combined velocity and attitude control system for the Planetary Explorer spacecraft. Both orbiter and probe-type missions to the planet Venus are considered. The spacecraft concept is that of a Delta launched spin-stabilized vehicle. Velocity control is obtained through preprogrammed pulse-mode firing of the thrusters in synchronism with the spacecraft spin rate. Configuration selection is found to be strongly influenced by the possible error torques induced by uncertainties in thruster operation and installation. The propulsion systems defined are based on maximum use of existing, qualified components. Ground support equipment requirements are defined and system development testing outlined.

  9. NASA electrothermal auxiliary propulsion technology

    NASA Technical Reports Server (NTRS)

    Stone, J. R.

    1986-01-01

    Electrothermal auxiliary propulsion systems provide high performance options which can have major mission benefits. There are several electrothermal concepts which offer a range of characteristics and benefits. Resistojets are the highest thrust to power option and are currently operational at mission average values of specific impulse, I sub sp approximately 295 sec. Long life, multipropellant resistojets are being developed for the space station, and resistojet technology advancements are being pursued to improve the I sub sp by more than 20 percent for resistojets used in satellite applications. Direct current arcjets have the potential of I sub sp over 400 sec with storable propellants and should provide over 1000 sec with hydrogen. Advanced concepts are being investigated to provide high power density options and possible growth to primary propulsion applications. Broad based experimental and analytical research and technology programs of NASA are summarized and recent significant advances are reviewed.

  10. Space Shuttle Propulsion Safety Upgrades

    NASA Technical Reports Server (NTRS)

    Humphries, William Randy, Jr.; McCool, Alex (Technical Monitor)

    2000-01-01

    This document is a viewgraph presentation which reviews the proposed upgrades to the Space Shuttle Propulsion system, to improve safety, and reduce significant hazards. The goals of the program are to reduce the risk of a catastrophe in ascent, to achieve significant reduction in orbital and entry systems, and to improve the crew cockpit situational awareness for managing the critical operational situations. The document reviews the upgrades to the propulsion system which are planned to improve the safety. These include modifications to the Advanced Thrust Vector Control, modifications to the Space Shuttle Main Engine Block III, improvement in the Advanced Health Management System, the use of Friction Stir welding on the external tank, which is expected to improve mechanical properties, and reduce defect rate, and the modification of the propellant grains geometry.

  11. Squirming propulsion in viscoelastic fluids

    NASA Astrophysics Data System (ADS)

    de Corato, Marco; Greco, Francesco; Maffettone, Pier Luca

    2015-11-01

    The locomotion of organisms in Newtonian fluids at low-Reynolds numbers displays very different features from that at large Reynolds numbers; indeed, in this regime the viscous forces are dominant over the inertial ones and propulsion is possible only with non-time-reversible swimming strokes. In many situations of biological interest, however, small organisms are propelling themselves through non-Newtonian fluids such as mucus or biofilms, which display highly viscoelastic properties. Fluid viscoelasticity affects in a complex way both the micro-organisms' swimming velocity and dissipated power, possibly affecting their collective behavior. In our work, we employ the so called ``squirmer'' model to study the motion of spherical ciliated organisms in a viscoelastic fluid. We derive analytical formulas for the squirmer swimming velocity and dissipated power that show a complex interplay between the fluid constitutive behavior and the propulsion mechanism.

  12. An assessment of liquid propulsion in the United States

    NASA Technical Reports Server (NTRS)

    Mccarty, John P.; Murphy, J. M.

    1989-01-01

    The paper examines the status of liquid propulsion capability and technology in the U.S. today versus where it needs to be to satisfy proposed near and long term goals. Attention is given to four areas of liquid propulsion: earth-to-orbit propulsion, orbital transfer propulsion, on-orbit and planetary propulsion, and advanced propulsion. Recommendations on improving the state of liquid propulsion in the U.S. are presented.

  13. Aerodynamic characteristics of a series of twin-inlet air-breathing missile configurations. 3: Axisymmetric and two-dimensional inlets at subsonic-transonic speeds

    NASA Technical Reports Server (NTRS)

    Hayes, C.

    1983-01-01

    A series of air-breathing missile configurations was investigated to provide a data base for the design of such missiles. The model could be configurated with either twin axisymmetric or two dimensional inlets. Three circumferential inlet locations were investigated: 90 deg, 115 deg, and 135 deg from the top center. Two vertical wing locations, as well as wingless configurations, were used. Three tail configurations were formed by locating the tail surfaces either on the inlet fairing or on the inlet fairing or on fairings on the body. The surfaces were used to provide pitch control. Two dimensional inlets with extended compression surfaces, used to improve the angle-of-attack performance of the inlets for wingless configurations, were also investigated. The twin axisymmetric two dimensional inlet types without internal flow are covered, and the boost configuration of an air-breathing missile is simulated.

  14. Quiet powered-lift propulsion

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Latest results of programs exploring new propulsion technology for powered-lift aircraft systems are presented. Topics discussed include results from the 'quiet clean short-haul experimental engine' program and progress reports on the 'quiet short-haul research aircraft' and 'tilt-rotor research aircraft' programs. In addition to these NASA programs, the Air Force AMST YC 14 and YC 15 programs were reviewed.

  15. Nuclear Thermal Propulsion Development Risks

    NASA Technical Reports Server (NTRS)

    Kim, Tony

    2015-01-01

    There are clear advantages of development of a Nuclear Thermal Propulsion (NTP) for a crewed mission to Mars. NTP for in-space propulsion enables more ambitious space missions by providing high thrust at high specific impulse ((is) approximately 900 sec) that is 2 times the best theoretical performance possible for chemical rockets. Missions can be optimized for maximum payload capability to take more payload with reduced total mass to orbit; saving cost on reduction of the number of launch vehicles needed. Or missions can be optimized to minimize trip time significantly to reduce the deep space radiation exposure to the crew. NTR propulsion technology is a game changer for space exploration to Mars and beyond. However, 'NUCLEAR' is a word that is feared and vilified by some groups and the hostility towards development of any nuclear systems can meet great opposition by the public as well as from national leaders and people in authority. The public often associates the 'nuclear' word with weapons of mass destruction. The development NTP is at risk due to unwarranted public fears and clear honest communication of nuclear safety will be critical to the success of the development of the NTP technology. Reducing cost to NTP development is critical to its acceptance and funding. In the past, highly inflated cost estimates of a full-scale development nuclear engine due to Category I nuclear security requirements and costly regulatory requirements have put the NTP technology as a low priority. Innovative approaches utilizing low enriched uranium (LEU). Even though NTP can be a small source of radiation to the crew, NTP can facilitate significant reduction of crew exposure to solar and cosmic radiation by reducing trip times by 3-4 months. Current Human Mars Mission (HMM) trajectories with conventional propulsion systems and fuel-efficient transfer orbits exceed astronaut radiation exposure limits. Utilizing extra propellant from one additional SLS launch and available

  16. Impeller for Water Jet Propulsion

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Marshall Space Flight Center engineers helped North American Marine Jet (NAMJ), Inc. improve the proposed design of a new impeller for jet propulsion system. With a three-dimensional computer model of the new marine jet engine blades, engineers were able to quickly create a solid ploycarbonate model of it. The rapid prototyping allowed the company to avoid many time-consuming and costly steps in creating the impeller.

  17. The 21st century propulsion

    NASA Technical Reports Server (NTRS)

    Haloulakos, V. E.; Boehmer, C.

    1990-01-01

    The prediction of future space travel in the next millennium starts by examining the past and extrapolating into the far future. Goals for the 21st century include expanded space travel and establishment of permanent manned outposts, and representation of Lunar and Mars outposts as the most immediate future in space. Nuclear stage design/program considerations; launch considerations for manned Mars missions; and far future propulsion schemes are outlined.

  18. Space Shuttle Propulsion Finishing Strong

    NASA Technical Reports Server (NTRS)

    Owen, James W.; Singer, Jody

    2011-01-01

    Numerous lessons have been documented from the Space Shuttle Propulsion elements. Major events include loss of the SRB's on STS-4 and shutdown of an SSME during ascent on STS- 51F. On STS-112 only half the pyrotechnics fired to release the vehicle from the launch pad, a testament for redundancy. STS-91 exhibited freezing of a main combustion chamber pressure measurement and on STS-93 nozzle tube ruptures necessitated a low liquid level oxygen cut off of the main engines. A number of on pad aborts were experienced during the early program resulting in delays. And the two accidents, STS-51L and STS-107, had unique heritage in history from early Program decisions and vehicle configuration. Following STS-51L significant resources were invested in developing fundamental physical understanding of solid rocket motor environments and material system behavior. Human rating of solid rocket motors was truly achieved. And following STS-107, the risk of ascent debris was better characterized and controlled. Situational awareness during all mission phases improved, and the management team instituted effective risk assessment practices. These major events and lessons for the future are discussed. The last 22 flights of the Space Shuttle, following the Columbia accident, were characterized by remarkable improvement in safety and reliability. Numerous problems were solved in addition to reduction of the ascent debris hazard. The propulsion system elements evolved to high reliability and heavy lift capability. The Shuttle system, though not a operable as envisioned in the 1970's, successfully assembled the International Space Station (ISS) and provided significant logistics and down mass for ISS operations. By the end of the Program, the remarkable Space Shuttle Propulsion system achieved very high performance, was largely reusable, exhibited high reliability, and is a heavy lift earth to orbit propulsion system. The story of this amazing system is discussed in detail in the paper.

  19. Antimatter propulsion, status and prospects

    NASA Technical Reports Server (NTRS)

    Howe, Steven D.; Hynes, Michael V.

    1986-01-01

    The use of advanced propulsion techniques must be considered if the currently envisioned launch date of the manned Mars mission were delayed until 2020 or later. Within the next thirty years, technological advances may allow such methods as beaming power to the ship, inertial-confinement fusion, or mass-conversion of antiprotons to become feasible. A propulsion system with an ISP of around 5000 s would allow the currently envisioned mission module to fly to Mars in 3 months and would require about one million pounds to be assembled in Earth orbit. Of the possible methods to achieve this, the antiproton mass-conversion reaction offers the highest potential, the greatest problems, and the most fascination. Increasing the production rates of antiprotons is a high priority task at facilities around the world. The application of antiprotons to propulsion requires the coupling of the energy released in the mass-conversion reaction to thrust-producing mechanisms. Recent proposals entail using the antiprotons to produce inertial confinement fusion or to produce negative muons which can catalyze fusion. By increasing the energy released per antiproton, the effective cost, (dollars/joule) can be reduced. These proposals and other areas of research can be investigated now. These short term results will be important in assessing the long range feasibility of an antiproton powered engine.

  20. Space station propulsion requirements study

    NASA Technical Reports Server (NTRS)

    Wilkinson, C. L.; Brennan, S. M.

    1985-01-01

    Propulsion system requirements to support Low Earth Orbit (LEO) manned space station development and evolution over a wide range of potential capabilities and for a variety of STS servicing and space station operating strategies are described. The term space station and the overall space station configuration refers, for the purpose of this report, to a group of potential LEO spacecraft that support the overall space station mission. The group consisted of the central space station at 28.5 deg or 90 deg inclinations, unmanned free-flying spacecraft that are both tethered and untethered, a short-range servicing vehicle, and a longer range servicing vehicle capable of GEO payload transfer. The time phasing for preferred propulsion technology approaches is also investigated, as well as the high-leverage, state-of-the-art advancements needed, and the qualitative and quantitative benefits of these advancements on STS/space station operations. The time frame of propulsion technologies applicable to this study is the early 1990's to approximately the year 2000.