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Sample records for advanced combustor design

  1. Advanced combustor design concept to control NOx and air toxics

    SciTech Connect

    Eddings, E.G.; Pershing, D.W.; Molina, A.; Sarofim, A.F.; Spinti, J.P.; Veranth, J.

    1999-03-29

    Direct coal combustion needs to be a primary energy source for the electric utility industry and for heavy manufacturing during the next several decades because of the availability and economic advantage of coal relative to other fuels and because of the time required to produce major market penetration in the energy field. However, the major obstacle to coal utilization is a set of ever-tightening environmental regulations at both the federal and local level. It is, therefore, critical that fundamental research be conducted to support the development of low-emission, high-efficiency pulverized coal power systems. The objective of this program was to develop fundamental understanding regarding the impact of fuel and combustion changes on NOx formation, carbon burnout and air toxic emissions from pulverized coal (pc) combustion. During pc combustion, nitrogen in the coal can be oxidized to form nitrogen oxides (NO{sub x}). The 1990 Clean Air Act Amendments established much stricter NO{sub x} emissions limits for new and existing coal-fired plants, so there has been renewed interest in the processes by which NO{sub x} forms in pc flames. One of the least understood aspects of NO{sub x} formation from pc combustion is the process by which char-N (nitrogen remaining in the char after devolatilization) forms either NO{sub x} or N{sub 2}, and the development of a fundamental understanding of this process was a major focus of this research. The overall objective of this program was to improve the ability of combustion system designers and boiler manufacturers to build high efficiency, low emission pulverized coal systems by improving the design tools available to the industry. The specific program goals were to: Use laboratory experiments and modeling to develop fundamental understanding for a new submodel for char nitrogen oxidation (a critical piece usually neglected in most NOx models.); Use existing bench scale facilities to investigate alternative schemes to

  2. TRW advanced slagging coal combustor utility demonstration

    SciTech Connect

    Not Available

    1990-01-01

    The TRW Advanced Entrained Coal Combustor Demonstration Project consists of retrofitting Orange and Rockland (O R) Utility Corporation's Lovett Plant Unit No. 3 with four (4) slagging combustors which will allow the gas/oil unit to fire 2.5% sulfur coal. The slagging combustor process will provide NO{sub x} and SO{sub x} emissions that meet NSPS and New York State Environmental Standards. The TRW-Utility Demonstration Unit (UDU) is responsible for the implementation of program policies and overall direction of the project. The following projects will be carried out: process and design development of clean coal technology CCT-1 the development and operation of the entrained coal combustor will enable the boiler to burn low and medium sulfur coal while meeting all the Federal/State emission requirements; demonstrate sulfur dioxide emissions control by pulverized limestone injection into the entrained coal combustor system.

  3. Low NOx Advanced Vortex Combustor

    SciTech Connect

    Edmonds, R.G.; Williams, J.T.; Steele, R.C.; Straub, D.L.; Casleton, K.H.; Bining, Avtar

    2008-05-01

    A lean-premixed advanced vortex combustor (AVC) has been developed and tested. The natural gas fueled AVC was tested at the U.S. Department of Energy’s National Energy Technology Laboratory in Morgantown, WV. All testing was performed at elevated pressures and inlet temperatures and at lean fuel-air ratios representative of industrial gas turbines. The improved AVC design exhibited simultaneous NOx /CO/unburned hydrocarbon (UHC) emissions of 4/4/0 ppmv (all emissions corrected to 15% O2 dry). The design also achieved less than 3 ppmv NOx with combustion efficiencies in excess of 99.5%. The design demonstrated marked acoustic dynamic stability over a wide range of operating conditions, which potentially makes this approach significantly more attractive than other lean-premixed combustion approaches. In addition, the measured 1.75% pressure drop is significantly lower than conventional gas turbine combustors, which could translate into an overall gas turbine cycle efficiency improvement. The relatively high velocities and low pressure drop achievable with this technology make the AVC approach an attractive alternative for syngas fuel applications.

  4. NASA/GE advanced low emissions combustor program

    NASA Technical Reports Server (NTRS)

    Ekstedt, E. E.; Fear, J. S.

    1987-01-01

    The Advanced Low Emissions Combustor Program consisted of the design and testing of advanced combustor concepts utilizing lean, premixed, prevaporized fuel and variable geometry. The objective was to evaluate the potential of these combustor systems to provide very low pollutant emissions levels, superior performance and high durability relative to contemporary combustor designs. Four full annular combustor concepts were designed and fabricated for a 30:1 pressure ratio high bypass turbofan engine. The four full annular combustors with active variable geometry were tested at pressures up to approximately 0.7 MPa with Jet A fuel. The two most promising concepts were also tested in a high pressure sector combustor test rig capable of operation at the maximum engine pressures. The high pressure sector combustor tests were conducted with Jet A and a fuel with reduced hydrogen content. Results of the sector combustor tests are presented in this paper. The potential for very low emissions with premixed fuel was demonstrated. However, autoignition or flashback within the premixing systems was encountered at high pressures. Further development effort is required to address this problem area.

  5. Advanced Low NOx Combustors for Aircraft Gas Turbines

    NASA Technical Reports Server (NTRS)

    Roberts, P. B.; White, D. J.; Shekleton, J. R.; Butze, H. F.

    1976-01-01

    A test rig program was conducted with the objective of evaluating and minimizing the exhaust emissions, in particular NOx, of two advanced aircraft combustor concepts at a simulated high-altitude cruise condition. The two pre-mixed, lean-reaction designs are known as the Jet Induced Circulation (JIC) combustor and the Vortex Air Blast (VAB) combustor and were rig tested in the form of reverse flow can combustors in the 0.13 ni (5.0 in. ) size range. Various configuration modifications were applied to the JIC and VAB combustor designs in an effort to reduce the emissions levels. The VAB combustor demonstrated a NOx level of 1.11 gm NO2/kg fuel with essentially 100 percent combustion efficiency at the simulated cruise combustor condition of 507 kPa (5 atm), 833 K (1500 R), inlet pressure and temperature respectively, and 1778 K (3200 R) outlet temperature on Jet-Al fuel. These configuration screening tests were carried out on essentially reaction zones only, in order to simplify the construction and modification of the combustors and to uncouple any possible effects on the emissions produced by the dilution flow. Tests were also conducted however at typical engine idle conditions on both combustors equipped with dilution ports in order to better define the problem areas involved in the operation of such concepts over a complete engine operational envelope. Versions of variable-geometry, JIC and VAB annular combustors are proposed.

  6. Advanced composite combustor structural concepts program

    NASA Technical Reports Server (NTRS)

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

    1984-01-01

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

  7. Energy efficient engine combustor test hardware detailed design report

    NASA Technical Reports Server (NTRS)

    Zeisser, M. H.; Greene, W.; Dubiel, D. J.

    1982-01-01

    The combustor for the Energy Efficient Engine is an annular, two-zone component. As designed, it either meets or exceeds all program goals for performance, safety, durability, and emissions, with the exception of oxides of nitrogen. When compared to the configuration investigated under the NASA-sponsored Experimental Clean Combustor Program, which was used as a basis for design, the Energy Efficient Engine combustor component has several technology advancements. The prediffuser section is designed with short, strutless, curved-walls to provide a uniform inlet airflow profile. Emissions control is achieved by a two-zone combustor that utilizes two types of fuel injectors to improve fuel atomization for more complete combustion. The combustor liners are a segmented configuration to meet the durability requirements at the high combustor operating pressures and temperatures. Liner cooling is accomplished with a counter-parallel FINWALL technique, which provides more effective heat transfer with less coolant.

  8. Development of an Advanced Annular Combustor

    NASA Technical Reports Server (NTRS)

    Rusnak, J. P.; Shadowen, J. H.

    1969-01-01

    The objective of the effort described in this report was to determine the structural durability of a full-scale advanced annular turbojet combustor using ASTM A-1 type fuel and operating at conditions typical of advanced supersonic aircraft. A full-scale annular combustor of the ram-induction type was fabricated and subjected to a 325-hour cyclic endurance test at conditions representative of operation in a Mach 3.0 aircraft. The combustor exhibited extensive cracking and scoop burning at the end of the test program. But these defects had no appreciable effect on combustor performance, as performance remained at a high level throughout the endurance program. Most performance goals were achieved with pressure loss values near 6% and 8%, and temperature rise variation ratio (deltaTVR) values near 1.25 and l.22 at takeoff and cruise conditions, respectively. Combustion efficiencies approached l004 and the exit radial temperature profiles were approximately as desired.

  9. ULTRA-LOW NOX ADVANCED VORTEX COMBUSTOR

    SciTech Connect

    Ryan G. Edmonds; Robert C. Steele; Joseph T. Williams; Douglas L. Straub; Kent H. Casleton; Avtar Bining

    2006-05-01

    An ultra lean-premixed Advanced Vortex Combustor (AVC) has been developed and tested. The natural gas fueled AVC was tested at the U.S. Department of Energy’s National Energy Technology Laboratory (USDOE NETL) test facility in Morgantown (WV). All testing was performed at elevated pressures and inlet temperatures and at lean fuel-air ratios representative of industrial gas turbines. The improved AVC design exhibited simultaneous NOx/CO/UHC emissions of 4/4/0 ppmv (all emissions are at 15% O2 dry). The design also achieved less than 3 ppmv NOx with combustion efficiencies in excess of 99.5%. The design demonstrated tremendous acoustic dynamic stability over a wide range of operating conditions which potentially makes this approach significantly more attractive than other lean premixed combustion approaches. In addition, a pressure drop of 1.75% was measured which is significantly lower than conventional gas turbine combustors. Potentially, this lower pressure drop characteristic of the AVC concept translates into overall gas turbine cycle efficiency improvements of up to one full percentage point. The relatively high velocities and low pressure drops achievable with this technology make the AVC approach an attractive alternative for syngas fuel applications.

  10. Ultra-Low NOx Advanced Vortex Combustor

    SciTech Connect

    Edmonds, R.G.; Steele, R.C.; Williams, J.T.; Straub, D.L.; Casleton, K.H.; Bining, Avtar

    2006-05-01

    An ultra lean-premixed Advanced Vortex Combustor (AVC) has been developed and tested. The natural gas fueled AVC was tested at the U.S. Department of Energy’s National Energy Technology Laboratory (USDOE NETL) test facility in Morgantown (WV). All testing was performed at elevated pressures and inlet temperatures and at lean fuel-air ratios representative of industrial gas turbines. The improved AVC design exhibited simultaneous NOx/CO/UHC emissions of 4/4/0 ppmv (all emissions are at 15% O2 dry). The design also achieved less than 3 ppmv NOx with combustion efficiencies in excess of 99.5%. The design demonstrated tremendous acoustic dynamic stability over a wide range of operating conditions which potentially makes this approach significantly more attractive than other lean premixed combustion approaches. In addition, a pressure drop of 1.75% was measured which is significantly lower than conventional gas turbine combustors. Potentially, this lower pressure drop characteristic of the AVC concept translates into overall gas turbine cycle efficiency improvements of up to one full percentage point. The relatively high velocities and low pressure drops achievable with this technology make the AVC approach an attractive alternative for syngas fuel applications.

  11. Advanced Catalytic Combustors for Low Pollutant Emissions

    DTIC Science & Technology

    1979-11-01

    concepts were selected for further design efforts. Results of the Phase I design effort indicate that catalytic combustion is a promising means for...L VAMD. Recent efforta to develop fuel-air carburetion concepts fol use in gas turbine catalytic combustion systems, which are summarized in...Radial/Axial Parallel-Staged combustor shown in F’gure 10 (Con- cept 6) is essentially two separate combustion systems in parallel. In this design concept

  12. Pulse Combustor Design, A DOE Assessment

    SciTech Connect

    National Energy Technology Laboratory

    2003-07-31

    The goal of the U.S. Department of Energy's (DOE) Clean Coal Technology (CCT) program is to furnish the energy marketplace with a number of advanced, more efficient, and environmentally responsible coal utilization technologies through demonstration projects. These projects seek to establish the commercial feasibility of the most promising advanced coal technologies that have developed beyond the proof-of-concept stage. This document serves as a DOE post-project assessment (PPA) of a project selected in CCT Round IV, the Pulse Combustor Design Qualification Test, as described in a Report to Congress (U.S. Department of Energy 1992). Pulse combustion is a method intended to increase the heat-transfer rate in a fired heater. The desire to demonstrate the use of pulse combustion as a source of heat for the gasification of coal, thus avoiding the need for an oxygen plant, prompted ThermoChem, Inc. (TCI), to submit a proposal for this project. In October 1992, TCI entered into a cooperative agreement with DOE to conduct this project. In 1998, the project was restructured and scaled down, and in September 1998, a new cooperative agreement was signed. The site of the revised project was TCI's facilities in Baltimore, Maryland. The original purpose of this CCT project was to demonstrate a unit that would employ ten identical 253-resonance tube combustors in a coal gasification unit. The objective of the scaled-down project was to test a single 253-resonance-tube combustor in a fluidized sand bed, with gasification being studied in a process development unit (PDU). DOE provided 50 percent of the total project funding of $8.6 million. The design for the demonstration unit was completed in February 1999, and construction was completed in November 2000. Operations were conducted in March 2001.

  13. Combustor design and analysis using the Rocket Combustor Interactive Design (ROCCID) methodology

    NASA Technical Reports Server (NTRS)

    Klem, Mark D.; Pieper, Jerry L.; Walker, Richard E.

    1990-01-01

    The ROCket Combustor Interactive Design (ROCCID) Methodology is a newly developed, interactive computer code for the design and analysis of a liquid propellant rocket combustion chamber. The application of ROCCID to design a liquid rocket combustion chamber is illustrated. Designs for a 50,000 lbf thrust and 1250 psi chamber pressure combustor using liquid oxygen (LOX)RP-1 propellants are developed and evaluated. Tradeoffs between key design parameters affecting combustor performance and stability are examined. Predicted performance and combustion stability margin for these designs are provided as a function of the combustor operating mixture ratio and chamber pressure.

  14. Combustor design and analysis using the ROCket Combustor Interactive Design (ROCCID) Methodology

    NASA Technical Reports Server (NTRS)

    Klem, Mark D.; Pieper, Jerry L.; Walker, Richard E.

    1990-01-01

    The ROCket Combustor Interactive Design (ROCCID) Methodology is a newly developed, interactive computer code for the design and analysis of a liquid propellant rocket combustion chamber. The application of ROCCID to design a liquid rocket combustion chamber is illustrated. Designs for a 50,000 lbf thrust and 1250 psi chamber pressure combustor using liquid oxygen (LOX)RP-1 propellants are developed and evaluated. Tradeoffs between key design parameters affecting combustor performance and stability are examined. Predicted performance and combustion stability margin for these designs are provided as a function of the combustor operating mixture ratio and chamber pressure.

  15. Advanced catalytic combustors for low pollutant emissions, phase 1

    NASA Technical Reports Server (NTRS)

    Dodds, W. J.

    1979-01-01

    The feasibility of employing the known attractive and distinguishing features of catalytic combustion technology to reduce nitric oxide emissions from gas turbine engines during subsonic, stratospheric cruise operation was investigated. Six conceptual combustor designs employing catalytic combustion were defined and evaluated for their potential to meet specific emissions and performance goals. Based on these evaluations, two parallel-staged, fixed-geometry designs were identified as the most promising concepts. Additional design studies were conducted to produce detailed preliminary designs of these two combustors. Results indicate that cruise nitric oxide emissions can be reduced by an order of magnitude relative to current technology levels by the use of catalytic combustion. Also, these combustors have the potential for operating over the EPA landing-takeoff cycle and at cruise with a low pressure drop, high combustion efficiency and with a very low overall level of emission pollutants. The use of catalytic combustion, however, requires advanced technology generation in order to obtain the time-temperature catalytic reactor performance and durability required for practical aircraft engine combustors.

  16. HSCT Sector Combustor Hardware Modifications for Improved Combustor Design

    NASA Technical Reports Server (NTRS)

    Greenfield, Stuart C.; Heberling, Paul V.; Moertle, George E.

    2005-01-01

    An alternative to the stepped-dome design for the lean premixed prevaporized (LPP) combustor has been developed. The new design uses the same premixer types as the stepped-dome design: integrated mixer flameholder (IMFH) tubes and a cyclone swirler pilot. The IMFH fuel system has been taken to a new level of development. Although the IMFH fuel system design developed in this Task is not intended to be engine-like hardware, it does have certain characteristics of engine hardware, including separate fuel circuits for each of the fuel stages. The four main stage fuel circuits are integrated into a single system which can be withdrawn from the combustor as a unit. Additionally, two new types of liner cooling have been designed. The resulting lean blowout data was found to correlate well with the Lefebvre parameter. As expected, CO and unburned hydrocarbons emissions were shown to have an approximately linear relationship, even though some scatter was present in the data, and the CO versus flame temperature data showed the typical cupped shape. Finally, the NOx emissions data was shown to agree well with a previously developed correlation based on emissions data from Configuration 3 tests performed at GEAE. The design variations of the cyclone swirler pilot that were investigated in this study did not significantly change the NOx emissions from the baseline design (GEAE Configuration 3) at supersonic cruise conditions.

  17. Advanced liner-cooling techniques for gas turbine combustors

    NASA Technical Reports Server (NTRS)

    Norgren, C. T.; Riddlebaugh, S. M.

    1985-01-01

    Component research for advanced small gas turbine engines is currently underway at the NASA Lewis Research Center. As part of this program, a basic reverse-flow combustor geometry was being maintained while different advanced liner wall cooling techniques were investigated. Performance and liner cooling effectiveness of the experimental combustor configuration featuring counter-flow film-cooled panels is presented and compared with two previously reported combustors featuring: splash film-cooled liner walls; and transpiration cooled liner walls (Lamilloy).

  18. National Combustion Code: A Multidisciplinary Combustor Design System

    NASA Technical Reports Server (NTRS)

    Stubbs, Robert M.; Liu, Nan-Suey

    1997-01-01

    The Internal Fluid Mechanics Division conducts both basic research and technology, and system technology research for aerospace propulsion systems components. The research within the division, which is both computational and experimental, is aimed at improving fundamental understanding of flow physics in inlets, ducts, nozzles, turbomachinery, and combustors. This article and the following three articles highlight some of the work accomplished in 1996. A multidisciplinary combustor design system is critical for optimizing the combustor design process. Such a system should include sophisticated computer-aided design (CAD) tools for geometry creation, advanced mesh generators for creating solid model representations, a common framework for fluid flow and structural analyses, modern postprocessing tools, and parallel processing. The goal of the present effort is to develop some of the enabling technologies and to demonstrate their overall performance in an integrated system called the National Combustion Code.

  19. Advanced low NO/x/ combustors for supersonic high-altitude aircraft gas turbines

    NASA Technical Reports Server (NTRS)

    Roberts, P. B.; Shekleton, J. R.; White, D. J.; Butze, H. F.

    1976-01-01

    A test rig program was conducted with the objective of evaluating and minimizing the exhaust emissions, in particular NO(x), of two advanced aircraft combustor concepts at a simulated, high-altitude cruise condition. The two combustor designs, both members of the lean-reaction, pre-mixed family, are known as the Jet Induced Circulation (JIC) combustor and the Vortex Air Blast (VAB) combustor and were rig tested in the form of reverse flow can combustors in the 0.127-m size range. Various configuration modifications were applied to each of the initial JIC and VAB combustor model designs in an effort to reduce the emissions levels. The VAB combustor demonstrated a NO(x) level of 1.1 gm NO2/kg fuel with essentially 100 percent combustion efficiency at the simulated cruise combustor condition of 507 kPa, 833 K inlet pressure and temperature, respectively and 1778 K outlet temperature on Jet-A1 fuel. In addition, emissions data were obtained at low combustor inlet pressure and temperatures that indicate the potential performance at engine off-design conditions.

  20. Materials for Advanced Turbine Engines (MATE): Project 3: Design, fabrication and evaluation of an oxide dispersion strengthened sheet alloy combustor liner, volume 1

    NASA Technical Reports Server (NTRS)

    Henricks, R. J.; Sheffler, K. D.

    1984-01-01

    The suitability of wrought oxide dispersion strengthened (ODS) superalloy sheet for gas turbine engine combustor applications was evaluated. Incoloy MA 956 (FeCrAl base) and Haynes Developmental Alloy (HDA) 8077 (NiCrAl base) were evaluated. Preliminary tests showed both alloys to be potentially viable combustor materials, with neither alloy exhibiting a significant advantage over the other. Both alloys demonstrated a +167C (300 F) advantage of creep and oxidation resistance with no improvement in thermal fatigue capability compared to a current generation combustor alloy (Hastelloy X). MA956 alloy was selected for further demonstration because it exhibited better manufacturing reproducibility than HDA8077. Additional property tests were conducted on MA956. To accommodate the limited thermal fatigue capability of ODS alloys, two segmented, mechanically attached, low strain ODS combustor design concepts having predicted fatigue lives or = 10,000 engine cycles were identified. One of these was a relatively conventional louvered geometry, while the other involved a transpiration cooled configuration. A series of 10,000 cycle combustor rig tests on subscale MA956 and Hastelloy X combustor components showed no cracking, thereby confirming the beneficial effect of the segmented design on thermal fatigue capability. These tests also confirmed the superior oxidation and thermal distortion resistance of the ODS alloy. A hybrid PW2037 inner burner liner containing MA956 and Hastelloy X components was designed and constructed.

  1. Advanced Low Emissions Subsonic Combustor Study

    NASA Technical Reports Server (NTRS)

    Smith, Reid

    1998-01-01

    Recent advances in commercial and military aircraft gas turbines have yielded significant improvements in fuel efficiency and thrust-to-weight ratio, due in large part to increased combustor operating pressures and temperatures. However, the higher operating conditions have increased the emission of oxides of nitrogen (NOx), which is a pollutant with adverse impact on the atmosphere and environment. Since commercial and military aircraft are the only important direct source of NOx emissions at high altitudes, there is a growing consensus that considerably more stringent limits on NOx emissions will be required in the future for all aircraft. In fact, the regulatory communities have recently agreed to reduce NOx limits by 20 percent from current requirements effective in 1996. Further reductions at low altitude, together with introduction of limits on NOx at altitude, are virtual certainties. In addition, the U.S. Government recently conducted hearings on the introduction of federal fees on the local emission of pollutants from all sources, including aircraft. While no action was taken regarding aircraft in this instance, the threat of future action clearly remains. In these times of intense and growing international competition, the U.S. le-ad in aerospace can only be maintained through a clear technological dominance that leads to a product line of maximum value to the global airline customer. Development of a very low NOx combustor will be essential to meet the future needs of both the commercial and military transport markets, if additional economic burdens and/or operational restrictions are to be avoided. In this report, Pratt & Whitney (P&W) presents the study results with the following specific objectives: Development of low-emissions combustor technologies for advances engines that will enter into service circa 2005, while producing a goal of 70 percent lower NOx emissions, compared to 1996 regulatory levels. Identification of solution approaches to

  2. The impact of emissions standards on the design of aircraft gas turbine engine combustors

    NASA Technical Reports Server (NTRS)

    Rudey, R. A.

    1976-01-01

    Effective emission control techniques have been identified and a wide spectrum of potential applications for these techniques to existing and advanced engines are being considered. Results from advanced combustor concept evaluations and from fundamental experiments are presented and discussed and comparisons are made with existing EPA emission standards and recommended levels for high altitude cruise. The impact that the advanced low emission concepts may impose on future aircraft engine combustor designs and related engine components is discussed.

  3. Advanced combustor design concepts to control NO{sub x} and air toxics. Quarterly report, [July--September 1996

    SciTech Connect

    Pershing, D.W.; Lighty, J.; Smith, P.; Spinti, J.; Veranth, J.; Domino, S.

    1996-09-30

    Understanding the mechanisms of char-N oxidation and reduction is necessary for the accurate modeling of NO, formation from coal combustion. This statement is especially true for combustors where low- NO{sub x} combustion modification techniques have been applied because in such cases the fraction of total fuel- NO{sub x} coming from the char is very high. This study has focused on obtaining experimental data that can be used to evaluate char-N oxidation and reduction mechanisms. The ultimate goal is to use this knowledge to improve the NO{sub x} submodel in an existing computational fluid dynamics (CFD) code. Several key experimental results were outlined in the report for the quarter ending 6/96. In order to clarify certain conclusions, more data were collected and analyzed during the quarter ending 9/96. Results from these new data as well as important results not included in the 6/96 report are addressed here.

  4. Active Combustion Control for Aircraft Gas-Turbine Engines-Experimental Results for an Advanced, Low-Emissions Combustor Prototype

    NASA Technical Reports Server (NTRS)

    DeLaat, John C.; Kopasakis, George; Saus, Joseph R.; Chang, Clarence T.; Wey, Changlie

    2012-01-01

    Lean combustion concepts for aircraft engine combustors are prone to combustion instabilities. Mitigation of instabilities is an enabling technology for these low-emissions combustors. NASA Glenn Research Center s prior activity has demonstrated active control to suppress a high-frequency combustion instability in a combustor rig designed to emulate an actual aircraft engine instability experience with a conventional, rich-front-end combustor. The current effort is developing further understanding of the problem specifically as applied to future lean-burning, very low-emissions combustors. A prototype advanced, low-emissions aircraft engine combustor with a combustion instability has been identified and previous work has characterized the dynamic behavior of that combustor prototype. The combustor exhibits thermoacoustic instabilities that are related to increasing fuel flow and that potentially prevent full-power operation. A simplified, non-linear oscillator model and a more physics-based sectored 1-D dynamic model have been developed to capture the combustor prototype s instability behavior. Utilizing these models, the NASA Adaptive Sliding Phasor Average Control (ASPAC) instability control method has been updated for the low-emissions combustor prototype. Active combustion instability suppression using the ASPAC control method has been demonstrated experimentally with this combustor prototype in a NASA combustion test cell operating at engine pressures, temperatures, and flows. A high-frequency fuel valve was utilized to perturb the combustor fuel flow. Successful instability suppression was shown using a dynamic pressure sensor in the combustor for controller feedback. Instability control was also shown with a pressure feedback sensor in the lower temperature region upstream of the combustor. It was also demonstrated that the controller can prevent the instability from occurring while combustor operation was transitioning from a stable, low-power condition to

  5. Development of an advanced high efficiency coal combustor for boiler retrofit

    SciTech Connect

    LaFlesh, R.C.; Rini, M.J.; McGowan, J.G.; Beer, J.M.; Toqan, M.A.

    1990-04-01

    The objective of the program was to develop an advanced coal combustion system for firing beneficiated coal fuels (BCFs) capable of being retrofitted to industrial boilers originally designed for firing natural gas. The High Efficiency Advanced Coal Combustor system is capable of firing microfine coal-water fuel (MCWF), MCWF with alkali sorbent (for SO{sub 2} reduction), and dry microfine coal. Design priorities for the system were that it be simple to operate and offer significant reductions in NO{sub x}, SO{sub x}, and particulate emissions as compared with current coal-fired combustor technology. (VC)

  6. Development of an advanced high efficiency coal combustor for boiler retrofit. Summary report

    SciTech Connect

    LaFlesh, R.C.; Rini, M.J.; McGowan, J.G.; Beer, J.M.; Toqan, M.A.

    1990-04-01

    The objective of the program was to develop an advanced coal combustion system for firing beneficiated coal fuels (BCFs) capable of being retrofitted to industrial boilers originally designed for firing natural gas. The High Efficiency Advanced Coal Combustor system is capable of firing microfine coal-water fuel (MCWF), MCWF with alkali sorbent (for SO{sub 2} reduction), and dry microfine coal. Design priorities for the system were that it be simple to operate and offer significant reductions in NO{sub x}, SO{sub x}, and particulate emissions as compared with current coal-fired combustor technology. (VC)

  7. Lean, premixed, prevaporized fuel combustor conceptual design study

    NASA Technical Reports Server (NTRS)

    Fiorentino, A. J.; Greene, W.; Kim, J.

    1979-01-01

    Four combustor concepts, designed for the energy efficient engine, utilize variable geometry or other flow modulation techniques to control the equivalence ratio of the initial burning zone. Lean conditions are maintained at high power to control oxides of nitrogen while near stoichometric conditions are maintained at low power for low CO and THC emissions. Each concept was analyzed and ranked for its potential in meeting the goals of the program. Although the primary goal of the program is a low level of nitric oxide emissions at stratospheric cruise conditions, both the ground level EPA emission standards and combustor performance and operational requirements typical of advanced subsonic aircraft engines are retained as goals as well. Based on the analytical projections made, two of the concepts offer the potential of achieving the emission goals; however, the projected operational characteristics and reliability of any concept to perform satisfactorily over an entire aircraft flight envelope would require extensive experimental substantiation before engine adaptation can be considered.

  8. MATE (Materials for Advanced Turbine Engines) Program, Project 3. Volume 2: Design, fabrication and evaluation of an oxide dispersion strengthened sheet alloy combustor liner

    NASA Technical Reports Server (NTRS)

    Bose, S.; Sheffler, K. D.

    1988-01-01

    The suitability of wrought oxide dispersion strengthened (ODS) superalloy sheet for gas turbine engine combustor applications was evaluated. Two yttria (Y2O3) dispersion strengthened alloys were evaluated; Incoloy MA956 and Haynes Development Alloy (HDA) 8077 (NiCrAl base). Preliminary tests showed both alloys to be potentially viable combustor materials, with neither alloy exhibiting a significant advantage over the other. MA956 was selected as the final alloy based on manufacturing reproducibility for evaluation as a burner liner. A hybrid PW2037 inner burner liner containing MA956 and Hastelloy X components and using a louvered configuration was designed and constructed. The louvered configuration was chosen because of field experience and compatibility with the bill of material PW2037 design. The simulated flight cycle for the ground based engine tests consisted of 4.5 min idle, 1.5 min takeoff and intermediate conditions in a PW2037 engine with average uncorrected combustor exit temperature of 1527 C. Post test evaluation consisting of visual observations and fluorescent penetrant inspections was conducted after 500 cycles of testing. No loss of integrity in the burner liner was shown.

  9. Advanced Low-Emissions Catalytic-Combustor Program, phase 1. [aircraft gas turbine engines

    NASA Technical Reports Server (NTRS)

    Sturgess, G. J.

    1981-01-01

    Six catalytic combustor concepts were defined, analyzed, and evaluated. Major design considerations included low emissions, performance, safety, durability, installations, operations and development. On the basis of these considerations the two most promising concepts were selected. Refined analysis and preliminary design work was conducted on these two concepts. The selected concepts were required to fit within the combustor chamber dimensions of the reference engine. This is achieved by using a dump diffuser discharging into a plenum chamber between the compressor discharge and the turbine inlet, with the combustors overlaying the prediffuser and the rear of the compressor. To enhance maintainability, the outer combustor case for each concept is designed to translate forward for accessibility to the catalytic reactor, liners and high pressure turbine area. The catalytic reactor is self-contained with air-cooled canning on a resilient mounting. Both selected concepts employed integrated engine-starting approaches to raise the catalytic reactor up to operating conditions. Advanced liner schemes are used to minimize required cooling air. The two selected concepts respectively employ fuel-rich initial thermal reaction followed by rapid quench and subsequent fuel-lean catalytic reaction of carbon monoxide, and, fuel-lean thermal reaction of some fuel in a continuously operating pilot combustor with fuel-lean catalytic reaction of remaining fuel in a radially-staged main combustor.

  10. Systems Characterization of Combustor Instabilities With Controls Design Emphasis

    NASA Technical Reports Server (NTRS)

    Kopasakis, George

    2004-01-01

    This effort performed test data analysis in order to characterize the general behavior of combustor instabilities with emphasis on controls design. The analysis is performed on data obtained from two configurations of a laboratory combustor rig and from a developmental aero-engine combustor. The study has characterized several dynamic behaviors associated with combustor instabilities. These are: frequency and phase randomness, amplitude modulations, net random phase walks, random noise, exponential growth and intra-harmonic couplings. Finally, the very cause of combustor instabilities was explored and it could be attributed to a more general source-load type impedance interaction that includes the thermo-acoustic coupling. Performing these characterizations on different combustors allows for more accurate identification of the cause of these phenomena and their effect on instability.

  11. Enabling Advanced Modeling and Simulations for Fuel-Flexible Combustors

    SciTech Connect

    Pitsch, Heinz

    2010-05-31

    The overall goal of the present project is to enable advanced modeling and simulations for the design and optimization of fuel-flexible turbine combustors. For this purpose we use a high fidelity, extensively-tested large-eddy simulation (LES) code and state-of-the-art models for premixed/partially-premixed turbulent combustion developed in the PI's group. In the frame of the present project, these techniques are applied, assessed, and improved for hydrogen enriched premixed and partially premixed gas-turbine combustion. Our innovative approaches include a completely consistent description of flame propagation; a coupled progress variable/level set method to resolve the detailed flame structure, and incorporation of thermal-diffusion (non-unity Lewis number) effects. In addition, we have developed a general flamelet-type transformation holding in the limits of both non-premixed and premixed burning. As a result, a model for partially premixed combustion has been derived. The coupled progress variable/level method and the general flamelet transformation were validated by LES of a lean-premixed low-swirl burner that has been studied experimentally at Lawrence Berkeley National Laboratory. The model is extended to include the non-unity Lewis number effects, which play a critical role in fuel-flexible combustor with high hydrogen content fuel. More specifically, a two-scalar model for lean hydrogen and hydrogen-enriched combustion is developed and validated against experimental and direct numerical simulation (DNS) data. Results are presented to emphasize the importance of non-unity Lewis number effects in the lean-premixed low-swirl burner of interest in this project. The proposed model gives improved results, which shows that the inclusion of the non-unity Lewis number effects is essential for accurate prediction of the lean-premixed low-swirl flame.

  12. Enabling Advanced Modeling and Simulations for Fuel-Flexible Combustors

    SciTech Connect

    Heinz Pitsch

    2010-05-31

    The overall goal of the present project is to enable advanced modeling and simulations for the design and optimization of fuel-flexible turbine combustors. For this purpose we use a high-fidelity, extensively-tested large-eddy simulation (LES) code and state-of-the-art models for premixed/partially-premixed turbulent combustion developed in the PI's group. In the frame of the present project, these techniques are applied, assessed, and improved for hydrogen enriched premixed and partially premixed gas-turbine combustion. Our innovative approaches include a completely consistent description of flame propagation, a coupled progress variable/level set method to resolve the detailed flame structure, and incorporation of thermal-diffusion (non-unity Lewis number) effects. In addition, we have developed a general flamelet-type transformation holding in the limits of both non-premixed and premixed burning. As a result, a model for partially premixed combustion has been derived. The coupled progress variable/level method and the general flamelet tranformation were validated by LES of a lean-premixed low-swirl burner that has been studied experimentally at Lawrence Berkeley National Laboratory. The model is extended to include the non-unity Lewis number effects, which play a critical role in fuel-flexible combustor with high hydrogen content fuel. More specifically, a two-scalar model for lean hydrogen and hydrogen-enriched combustion is developed and validated against experimental and direct numerical simulation (DNS) data. Results are presented to emphasize the importance of non-unity Lewis number effects in the lean-premixed low-swirl burner of interest in this project. The proposed model gives improved results, which shows that the inclusion of the non-unity Lewis number effects is essential for accurate prediction of the lean-premixed low-swirl flame.

  13. Energy Efficient Engine combustor test hardware detailed design report

    NASA Technical Reports Server (NTRS)

    Burrus, D. L.; Chahrour, C. A.; Foltz, H. L.; Sabla, P. E.; Seto, S. P.; Taylor, J. R.

    1984-01-01

    The Energy Efficient Engine (E3) Combustor Development effort was conducted as part of the overall NASA/GE E3 Program. This effort included the selection of an advanced double-annular combustion system design. The primary intent was to evolve a design which meets the stringent emissions and life goals of the E3 as well as all of the usual performance requirements of combustion systems for modern turbofan engines. Numerous detailed design studies were conducted to define the features of the combustion system design. Development test hardware was fabricated, and an extensive testing effort was undertaken to evaluate the combustion system subcomponents in order to verify and refine the design. Technology derived from this development effort will be incorporated into the engine combustion system hardware design. This advanced engine combustion system will then be evaluated in component testing to verify the design intent. What is evolving from this development effort is an advanced combustion system capable of satisfying all of the combustion system design objectives and requirements of the E3. Fuel nozzle, diffuser, starting, and emissions design studies are discussed.

  14. Experimental clean combustor program, phase 1

    NASA Technical Reports Server (NTRS)

    Bahr, D. W.; Gleason, C. C.

    1975-01-01

    Full annular versions of advanced combustor designs, sized to fit within the CF6-50 engine, were defined, manufactured, and tested at high pressure conditions. Configurations were screened, and significant reductions in CO, HC, and NOx emissions levels were achieved with two of these advanced combustor design concepts. Emissions and performance data at a typical AST cruise condition were also obtained along with combustor noise data as a part of an addendum to the basic program. The two promising combustor design approaches evolved in these efforts were the Double Annular Combustor and the Radial/Axial Combustor. With versions of these two basic combustor designs, CO and HC emissions levels at or near the target levels were obtained. Although the low target NOx emissions level was not obtained with these two advanced combustor designs, significant reductions were relative to the NOx levels of current technology combustors. Smoke emission levels below the target value were obtained.

  15. Advanced Low-Emissions Catalytic Combustor Program

    DTIC Science & Technology

    1981-06-01

    Program Goals 5 3.2 Reference Engine Description 6 4.0 GENERAL AEROTHERMODYNAMIC AND MECHANICAL DESIGN STUDIES 11 4.1 Combustion Concepts 11 4.2...Pressure Loss Variation with Reactor Length 29 22 Preliminary Flowpath for Concept 2 31 23 Dependence of Idle Combustion Efficiency on Equivalence Ratio...Controlled Variable Geometry 52 38 Concept 4: Combustion Stability Margin Dependence on Cruise Conditions for Engine Speed-Controlled Variable

  16. Development of an advanced high efficiency coal combustor for boiler retrofit

    SciTech Connect

    LaFlesh, R.C.; Rini, M.J.; McGowan, J.G.

    1989-10-01

    The overall objective of this program is to develop a high efficiency advanced coal combustor (HEACC) for coal-based fuels capable of being retrofitted to industrial boilers originally designed for firing natural gas, distillate, and/or residual oil. The HEACC system is to be capable of firing microfine coal water fuel (MCWF), MCWF with alkali sorbent (for SO{sub 2} reduction), and dry microfine coal. Design priorities for the system are that it be simple to operate and will offer significant reductions in NO{sub x}, SO{sub x}, and particulate emissions as compared with current coal fired combustor technology. The specific objective of this report is to document the work carried out under Task 1.0 of this contract, Cold Flow Burner Development''. As are detailed in the report, key elements of this work included primary air swirler development, burner register geometry design, cold flow burner model testing, and development of burner scale up criteria.

  17. Advanced pulverized coal combustor for control of NO/sub x/ emissions. First quarterly report, September 24-December 24, 1980

    SciTech Connect

    Pam, R.; Chu, E. K.; Kelly, J. T.

    1981-01-30

    The first quarter results under the Advanced Pulverized Coal Combustor for Control of NO/sub x/ Emissions Program (DOE Contract DE-AC22-80PC30296) are reported. A preliminary gas phase reaction model for predicting fuel NO/sub x/ formation during combustion of methane fuel has been constructed. Predictions of NO/sub x/ formation under stirred reactor conditions agree with existing experimental data. Thermal NO/sub x/ and coal reaction data will be developed and verified during the next reporting period. Progress has been made in formulating the changes necessary to upgrade the Acurex PROF code for use as the comprehensive data analysis tool in this program. The radiation modeling and the incorporation of the needed modifications into the PROF code will occur during the next reporting period. The idealized combustor was designed, and requests for bids to fabricate the combustor were submitted. Combustor fabrication will be completed during the next reporting period.

  18. Small Engine Technology (SET) - Task 4, Regional Turboprop/Turbofan Engine Advanced Combustor Study

    NASA Technical Reports Server (NTRS)

    Reynolds, Robert; Srinivasan, Ram; Myers, Geoffrey; Cardenas, Manuel; Penko, Paul F. (Technical Monitor)

    2003-01-01

    Under the SET Program Task 4 - Regional Turboprop/Turbofan Engine Advanced Combustor Study, a total of ten low-emissions combustion system concepts were evaluated analytically for three different gas turbine engine geometries and three different levels of oxides of nitrogen (NOx) reduction technology, using an existing AlliedSignal three-dimensional (3-D) Computational Fluid Dynamics (CFD) code to predict Landing and Takeoff (LTO) engine cycle emission values. A list of potential Barrier Technologies to the successful implementation of these low-NOx combustor designs was created and assessed. A trade study was performed that ranked each of the ten study configurations on the basis of a number of manufacturing and durability factors, in addition to emissions levels. The results of the trade study identified three basic NOx-emissions reduction concepts that could be incorporated in proposed follow-on combustor technology development programs aimed at demonstrating low-NOx combustor hardware. These concepts are: high-flow swirlers and primary orifices, fuel-preparation cans, and double-dome swirlers.

  19. National Combustion Code, a Multidisciplinary Combustor Design System, Will Be Transferred to the Commercial Sector

    NASA Technical Reports Server (NTRS)

    Steele, Gynelle C.

    1999-01-01

    The NASA Lewis Research Center and Flow Parametrics will enter into an agreement to commercialize the National Combustion Code (NCC). This multidisciplinary combustor design system utilizes computer-aided design (CAD) tools for geometry creation, advanced mesh generators for creating solid model representations, a common framework for fluid flow and structural analyses, modern postprocessing tools, and parallel processing. This integrated system can facilitate and enhance various phases of the design and analysis process.

  20. Lean, Premixed-Prevaporized (LPP) combustor conceptual design study

    NASA Technical Reports Server (NTRS)

    Dickman, R. A.; Dodds, W. J.; Ekstedt, E. E.

    1979-01-01

    Four combustion systems were designed and sized for the energy efficient engine. A fifth combustor was designed for the cycle and envelope of the twin-spool, high bypass ratio, high pressure ratio turbofan engine. Emission levels, combustion performance, life, and reliability assessments were made for these five combustion systems. Results of these design studies indicate that cruise NOx emission can be reduced by the use of lean, premixed-prevaporaized combustion and airflow modulation.

  1. Effect of model selection on combustor performance and stability using ROCCID. [Rocket Combustor Interactive Design

    NASA Technical Reports Server (NTRS)

    Giuliani, James E.; Klem, Mark D.

    1992-01-01

    The ROCket Combustor Interactive Design (ROCCID) methodology is an interactive computer program that combines previously developed combustion analysis models to calculate the combustion performance and stability of liquid rocket engines. Test data from a 213 kN (48,000 lbf) Liquid Oxygen (LOX)/RP-1 combustor with a O-F-O (oxidizer-fuel-oxidizer) triplet injector were used to characterize the predictive capabilities of the ROCCID analysis models for this injector/propellant configuration. Thirteen combustion performance and stability models have been incorporated into ROCCID, and ten of them, which have options for triplet injectors, were examined in this study. Calculations using different combinations of analysis models, with little or no anchoring, were carried out on a test matrix of operating conditions matching those of the test program. Results of the computer analyses were compared to test data, and the ability of the model combinations to correctly predict combustion stability or instability was determined. For the best model combination(s), sensitivity of the calculations to fuel drop size and mixing efficiency was examined. Error in the stability calculations due to uncertainty in the pressure interaction index (N) was examined. The recommended model combinations for this O-F-O triplet LOX/RP-1 configuration are proposed.

  2. Melt Infiltrated Ceramic Matrix Composites for Shrouds and Combustor Liners of Advanced Industrial Gas Turbines

    SciTech Connect

    Gregory Corman; Krishan Luthra; Jill Jonkowski; Joseph Mavec; Paul Bakke; Debbie Haught; Merrill Smith

    2011-01-07

    This report covers work performed under the Advanced Materials for Advanced Industrial Gas Turbines (AMAIGT) program by GE Global Research and its collaborators from 2000 through 2010. A first stage shroud for a 7FA-class gas turbine engine utilizing HiPerComp{reg_sign}* ceramic matrix composite (CMC) material was developed. The design, fabrication, rig testing and engine testing of this shroud system are described. Through two field engine tests, the latter of which is still in progress at a Jacksonville Electric Authority generating station, the robustness of the CMC material and the shroud system in general were demonstrated, with shrouds having accumulated nearly 7,000 hours of field engine testing at the conclusion of the program. During the latter test the engine performance benefits from utilizing CMC shrouds were verified. Similar development of a CMC combustor liner design for a 7FA-class engine is also described. The feasibility of using the HiPerComp{reg_sign} CMC material for combustor liner applications was demonstrated in a Solar Turbines Ceramic Stationary Gas Turbine (CSGT) engine test where the liner performed without incident for 12,822 hours. The deposition processes for applying environmental barrier coatings to the CMC components were also developed, and the performance of the coatings in the rig and engine tests is described.

  3. Clean catalytic combustor program

    NASA Technical Reports Server (NTRS)

    Ekstedt, E. E.; Lyon, T. F.; Sabla, P. E.; Dodds, W. J.

    1983-01-01

    A combustor program was conducted to evolve and to identify the technology needed for, and to establish the credibility of, using combustors with catalytic reactors in modern high-pressure-ratio aircraft turbine engines. Two selected catalytic combustor concepts were designed, fabricated, and evaluated. The combustors were sized for use in the NASA/General Electric Energy Efficient Engine (E3). One of the combustor designs was a basic parallel-staged double-annular combustor. The second design was also a parallel-staged combustor but employed reverse flow cannular catalytic reactors. Subcomponent tests of fuel injection systems and of catalytic reactors for use in the combustion system were also conducted. Very low-level pollutant emissions and excellent combustor performance were achieved. However, it was obvious from these tests that extensive development of fuel/air preparation systems and considerable advancement in the steady-state operating temperature capability of catalytic reactor materials will be required prior to the consideration of catalytic combustion systems for use in high-pressure-ratio aircraft turbine engines.

  4. Performance of an annual combustor designed for a low-cost turbojet engine

    NASA Technical Reports Server (NTRS)

    Fear, J. S.

    1973-01-01

    Performance tests were conducted on a combustor designed for use in a low-cost turbojet engine. Low-cost features included the use of very inexpensive simplex fuel nozzles and combustor liners of perforated sheet material. Combustion efficiencies at the altitude-cruise and sea-level design points were approximately 94 and 96 percent, respectively. The combustor isothermal total-pressure loss was 8.8 percent at the altitude-cruise-condition diffuser-inlet Mach number of 0.335. The combustor-exit temperature pattern factor was less than 0.3 at the altitude-cruise, sea-level-cruise, and sea-level-static design conditions. The combustor-exit average radial temperature profiles at all conditions were in very good agreement with the design profile. The intense mixing required because of the very high combustor heat-release rate had an adverse effect on ignition capability at altitude windmilling design conditions.

  5. Combustor diffuser interaction program

    NASA Technical Reports Server (NTRS)

    Srinivasan, Ram; Thorp, Daniel

    1986-01-01

    Advances in gas turbine engine performance are achieved by using compressor systems with high stage loading and low part count, which result in high exit Mach numbers. The diffuser and combustor systems in such engines should be optimized to reduce system pressure loss and to maximize the engine thrust-to-weight ratio and minimize length. The state-of-the-art combustor-diffuser systems do not meet these requirements. Detailed understanding of the combustor-diffuser flow field interaction is required for designing advanced gas turbine engines. An experimental study of the combustor-diffuser interaction (CDI) is being conducted to obtain data for the evaluation and improvement of analytical models applicable to a wide variety of diffuser designs. The CDI program consists of four technical phases: Literature Search; Baseline Configuration; Parametric Configurations; and Performance Configurations. Phase 2 of the program is in progress.

  6. Wide range operation of advanced low NOx combustors for supersonic high-altitude aircraft gas turbines

    NASA Technical Reports Server (NTRS)

    Roberts, P. B.; Fiorito, R. J.

    1977-01-01

    An initial rig program tested the Jet Induced Circulation (JIC) and Vortex Air Blast (VAB) systems in small can combustor configurations for NOx emissions at a simulated high altitude, supersonic cruise condition. The VAB combustor demonstrated the capability of meeting the NOx goal of 1.0 g NO2/kg fuel at the cruise condition. In addition, the program served to demonstrate the limited low-emissions range available from the lean, premixed combustor. A follow-on effort was concerned with the problem of operating these lean, premixed combustors with acceptable emissions at simulated engine idle conditions. Various techniques have been demonstrated that allow satisfactory operation on both the JIC and VAB combustors at idle with CO emissions below 20 g/kg fuel. The VAB combustor was limited by flashback/autoignition phenomena at the cruise conditions to a pressure of 8 atmospheres. The JIC combustor was operated up to the full design cruise pressure of 14 atmospheres without encountering an autoignition limitation although the NOx levels, in the 2-3 g NO2/kg fuel range, exceeded the program goal.

  7. Development of an advanced high efficiency coal combustor for boiler retrofit. Task 1, Cold flow burner development: Final report

    SciTech Connect

    LaFlesh, R.C.; Rini, M.J.; McGowan, J.G.

    1989-10-01

    The overall objective of this program is to develop a high efficiency advanced coal combustor (HEACC) for coal-based fuels capable of being retrofitted to industrial boilers originally designed for firing natural gas, distillate, and/or residual oil. The HEACC system is to be capable of firing microfine coal water fuel (MCWF), MCWF with alkali sorbent (for SO{sub 2} reduction), and dry microfine coal. Design priorities for the system are that it be simple to operate and will offer significant reductions in NO{sub x}, SO{sub x}, and particulate emissions as compared with current coal fired combustor technology. The specific objective of this report is to document the work carried out under Task 1.0 of this contract, ``Cold Flow Burner Development``. As are detailed in the report, key elements of this work included primary air swirler development, burner register geometry design, cold flow burner model testing, and development of burner scale up criteria.

  8. Design of thermal protection system for 8 foot HTST combustor

    NASA Technical Reports Server (NTRS)

    Moskowitz, S.

    1973-01-01

    The combustor in the 8-foot high temperature structures tunnel at the NASA-Langley Research Center has encountered cracking over a period of 50-250 tunnel tests within a limited range of the required operating envelope. A program was conducted which analyzed the failed combustor liner hardware and determined that the mechanism of failure was vibratory fatigue. A vibration damper system using wave springs located axially between the liner T-bar and the liner support was designed as an intermediate solution to extend the life of the current two-pass regenerative air-cooled liner. The effects of liner wall thickness, cooling air passage height, stiffener ring geometry, reflective coatings, and liner material selection were investigated for these designs. Preliminary layout design arrangements including the external water-cooling system requirements, weight estimates, installation requirements and preliminary estimates of manufacturing costs were prepared for the most promissing configurations. A state-of-the-art review of thermal barrier coatings and an evaluation of reflective coatings for the gasside surface of air-cooled liners are included.

  9. Toward improved durability in advanced combustors and turbines: Progress in the prediction of thermomechanical loads

    NASA Technical Reports Server (NTRS)

    Sokolowski, Daniel E.; Ensign, C. Robert

    1986-01-01

    NASA is sponsoring the Turbine Engine Hot Section Technology (HOST) Project to address the need for improved durability in advanced combustors and turbines. Analytical and experimental activities aimed at more accurate prediction of the aerothermal environment, the thermomechanical loads, the material behavior and structural responses to such loading, and life predictions for high temperature cyclic operation have been underway for several years and are showing promising results. Progress is reported in the development of advanced instrumentation and in the improvement of combustor aerothermal and turbine heat transfer models that will lead to more accurate prediction of thermomechanical loads.

  10. Parametric Design of Injectors for LDI-3 Combustors

    NASA Technical Reports Server (NTRS)

    Ajmani, Kumud; Mongia, Hukam; Lee, Phil

    2015-01-01

    Application of a partially calibrated National Combustion Code (NCC) for providing guidance in the design of the 3rd generation of the Lean-Direct Injection (LDI) multi-element combustion configuration (LDI-3) is summarized. NCC was used to perform non-reacting and two-phase reacting flow computations on several LDI-3 injector configurations in a single-element and a five-element injector array. All computations were performed with a consistent approach for mesh-generation, turbulence, spray simulations, ignition and chemical kinetics-modeling. Both qualitative and quantitative assessment of the computed flowfield characteristics of the several design options led to selection of an optimal injector LDI- 3 design that met all the requirements including effective area, aerodynamics and fuel-air mixing criteria. Computed LDI-3 emissions (namely, NOx, CO and UHC) will be compared with the prior generation LDI- 2 combustor experimental data at relevant engine cycle conditions.

  11. The Coal Tech Advanced Cyclone Combustor Demonstration Project: A DOE assessment

    SciTech Connect

    Not Available

    1993-05-01

    The objective of this project was to demonstrate a technology for retrofitting oil/gas designed boilers, and conventional pulverized coal-fired boilers, by using the patented air-cooled slagging coal combustor in place of oil/gas/coal burners. The project aimed to utilize coals with a wide range of sulfur contents and to achieve efficient combustion under fuel-rich conditions. The three performance goals of the combustor were to limit emissions of SO{sub 2} and NO{sub x}, while maintaining maximum sulfur retention in the slag removed from the combustor. A slagging cyclone combustor is a high-temperature device in which a high-velocity swirling gas is used to burn crushed or pulverized coal. The key novel feature of this combustor is the use of air cooling. This is accomplished by using a ceramic liner which is cooled by secondary air and maintained at a temperature high enough to keep the slag in a liquid, free-flowing state. The arrangement also promotes slag retention in the combustor, an important feature for retrofitting in boilers designed for oil/gas.

  12. N+2 Advanced Low NOx Combustor Technology Final Report

    NASA Technical Reports Server (NTRS)

    Herbon, John; Aicholtz, John; Hsieh, Shih-Yang; Viars, Philip; Birmaher, Shai; Brown, Dan; Patel, Nayan; Carper, Doug; Cooper, Clay; Fitzgerald, Russell

    2017-01-01

    In accordance with NASAs technology goals for future subsonic vehicles, this contract identified and developed new combustor concepts toward meeting N+2 generation (2020) LTO (landing and take-off) NOx emissions reduction goal of 75 from the standard adopted at Committee on Aviation Environmental Protection 6 (CAEP6). Based on flame tube emissions, operability, and autoignition testing, one concept was down selected for sector testing at NASA. The N+2 combustor sector successfully demonstrated 75 reduction for LTO NOx (vs. CAEP6) and cruise NOx (vs. 2005 B777-200 reference) while maintaining 99.9 cruise efficiency and no increase in CO and HC emissions.The program also developed enabling technologies for the combustion system including ceramic matrix composites (CMC) liner materials, active combustion control concepts, and laser ignition for improved altitude relight.

  13. Effect of design features on performance of a double-annular ram-induction combustor

    NASA Technical Reports Server (NTRS)

    Schultz, D. F.

    1975-01-01

    An extensive test program was undertaken to determine the effect of many design features such as the size and number of air scoops, and the type of diffuser airflow distribution to use to optimize performance of a double-annular ram-induction combustor of 94 cm outer diameter. Six combustor configurations were tested. It was found that a snouted double annular combustor built with 256 ram-induction air scoops with a combustor open area giving a total pressure loss of 5.0 percent at a diffuser inlet Mach number of 0.25 gave the best overall performance of the configurations tested.

  14. Investigation of heat transfer and combustion in the advanced fluidized bed combustor (FBC)

    SciTech Connect

    Lee, S.W.

    1999-09-01

    This technical report summarizes the research conducted and progress achieved during the period from April 1, 1998 to June 30, 1998. The numerical simulation was continued to determine the concentration distribution of the gas species, heat flux and heat transfer coefficients in the hot combustor model. The different gas concentration profiles showed the gas mixing characteristics along the combustor height. The center zone of the combustor has a relatively high methane mass concentration. The injection of secondary air squeezes the uprising flue gas and methane that causes the fuel-lean zone near the secondary air nozzles. The carbon dioxide concentration increased with the increasing of the combustor height. The peak concentration of oxygen remains at the combustor wall because of the secondary injection. The heat flux on the wall of the upper chamber is much higher than that of the lower chamber. It is believed that the heat flux is affected by the designed strong swirl and secondary air injection. The heat transfer coefficient changes along the combustor height were also affected by the multiple secondary air injection. The numerical simulation results could verify the predictions of the experimental results. It is a quite similar trend of the heat transfer coefficient changes based on the combustion test results.

  15. Characterization and Simulation of the Thermoacoustic Instability Behavior of an Advanced, Low Emissions Combustor Prototype

    NASA Technical Reports Server (NTRS)

    DeLaat, John C.; Paxson, Daniel E.

    2008-01-01

    Extensive research is being done toward the development of ultra-low-emissions combustors for aircraft gas turbine engines. However, these combustors have an increased susceptibility to thermoacoustic instabilities. This type of instability was recently observed in an advanced, low emissions combustor prototype installed in a NASA Glenn Research Center test stand. The instability produces pressure oscillations that grow with increasing fuel/air ratio, preventing full power operation. The instability behavior makes the combustor a potentially useful test bed for research into active control methods for combustion instability suppression. The instability behavior was characterized by operating the combustor at various pressures, temperatures, and fuel and air flows representative of operation within an aircraft gas turbine engine. Trends in instability behavior versus operating condition have been identified and documented, and possible explanations for the trends provided. A simulation developed at NASA Glenn captures the observed instability behavior. The physics-based simulation includes the relevant physical features of the combustor and test rig, employs a Sectored 1-D approach, includes simplified reaction equations, and provides time-accurate results. A computationally efficient method is used for area transitions, which decreases run times and allows the simulation to be used for parametric studies, including control method investigations. Simulation results show that the simulation exhibits a self-starting, self-sustained combustion instability and also replicates the experimentally observed instability trends versus operating condition. Future plans are to use the simulation to investigate active control strategies to suppress combustion instabilities and then to experimentally demonstrate active instability suppression with the low emissions combustor prototype, enabling full power, stable operation.

  16. Experimental clean combustor program noise measurement addendum, phase 1

    NASA Technical Reports Server (NTRS)

    Emmerling, J. J.

    1975-01-01

    The test results of combustor noise measurements taken with waveguide probes are presented. Waveguide probes were shown to be a viable measurement technique for determining high sound pressure level broadband noise. A total of six full-scale annular combustors were tested and included the three advanced combustor designs: swirl-can, radial/axial, and double annular.

  17. Experimental clean combustor program; noise measurement addendum, Phase 2

    NASA Technical Reports Server (NTRS)

    Emmerling, J. J.; Bekofske, K. L.

    1976-01-01

    Combustor noise measurements were performed using wave guide probes. Test results from two full scale annular combustor configurations in a combustor test rig are presented. A CF6-50 combustor represented a current design, and a double annular combustor represented the advanced clean combustor configuration. The overall acoustic power levels were found to correlate with the steady state heat release rate and inlet temperature. A theoretical analysis for the attenuation of combustor noise propagating through a turbine was extended from a subsonic relative flow condition to include the case of supersonic flow at the discharge side. The predicted attenuation from this analysis was compared to both engine data and extrapolated component combustor data. The attenuation of combustor noise through the CF6-50 turbine was found to be greater than 14 dB by both the analysis and the data.

  18. Investigation of heat transfer and combustion in the advanced fluidized bed combustor (FBC)

    SciTech Connect

    Dr. Seong W. Lee

    1998-10-01

    The objective of this project is to predict the heat transfer and combustion performance in newly-designed fluidized bed combustor (FBC) and to provide the design guide lines and innovative concept for small-scale boiler and furnace. The major accomplishments are summarized.

  19. Wide range operation of advanced low NOx aircraft gas turbine combustors

    NASA Technical Reports Server (NTRS)

    Roberts, P. B.; Fiorito, R. J.; Butze, H. F.

    1978-01-01

    The paper summarizes the results of an experimental test rig program designed to define and demonstrates techniques which would allow the jet-induced circulation and vortex air blast combustors to operate stably with acceptable emissions at simulated engine idle without compromise to the low NOx emissions under the high-altitude supersonic cruise condition. The discussion focuses on the test results of the key combustor modifications for both the simulated engine idle and cruise conditions. Several range-augmentation techniques are demonstrated that allow the lean-reaction premixed aircraft gas turbine combustor to operate with low NOx emissons at engine cruise and acceptable CO and UHC levels at engine idle. These techniques involve several combinations, including variable geometry and fuel switching designs.

  20. Effects of fuel nozzle design on performance of an experimental annular combustor using natural gas fuel

    NASA Technical Reports Server (NTRS)

    Wear, J. D.; Schultz, D. F.

    1972-01-01

    Tests of various fuel nozzles were conducted with natural gas fuel in a full-annulus combustor. The nozzles were designed to provide either axial, angled, or radial fuel injection. Each fuel nozzle was evaluated by measuring combustion efficiency at relatively severe combustor operating conditions. Combustor blowout and altitude ignition tests were also used to evaluate nozzle designs. Results indicate that angled injection gave higher combustion efficiency, less tendency toward combustion instability, and altitude relight characteristics equal to or superior to those of the other fuel nozzles that were tested.

  1. Design and preliminary results of a fuel flexible industrial gas turbine combustor

    NASA Technical Reports Server (NTRS)

    Novick, A. S.; Troth, D. L.; Yacobucci, H. G.

    1981-01-01

    The design characteristics are presented of a fuel tolerant variable geometry staged air combustor using regenerative/convective cooling. The rich/quench/lean variable geometry combustor is designed to achieve low NO(x) emission from fuels containing fuel bound nitrogen. The physical size of the combustor was calculated for a can-annular combustion system with associated operating conditions for the Allison 570-K engine. Preliminary test results indicate that the concept has the potential to meet emission requirements at maximum continuous power operation. However, airflow sealing and improved fuel/air mixing are necessary to meet Department of Energy program goals.

  2. Engine-Scale Combustor Rig Designed, Fabricated, and Tested for Combustion Instability Control Research

    NASA Technical Reports Server (NTRS)

    DeLaat, John C.; Breisacher, Kevin J.

    2000-01-01

    Low-emission combustor designs are prone to combustor instabilities. Because active control of these instabilities may allow future combustors to meet both stringent emissions and performance requirements, an experimental combustor rig was developed for investigating methods of actively suppressing combustion instabilities. The experimental rig has features similar to a real engine combustor and exhibits instabilities representative of those in aircraft gas turbine engines. Experimental testing in the spring of 1999 demonstrated that the rig can be tuned to closely represent an instability observed in engine tests. Future plans are to develop and demonstrate combustion instability control using this experimental combustor rig. The NASA Glenn Research Center at Lewis Field is leading the Combustion Instability Control program to investigate methods for actively suppressing combustion instabilities. Under this program, a single-nozzle, liquid-fueled research combustor rig was designed, fabricated, and tested. The rig has many of the complexities of a real engine combustor, including an actual fuel nozzle and swirler, dilution cooling, and an effusion-cooled liner. Prior to designing the experimental rig, a survey of aircraft engine combustion instability experience identified an instability observed in a prototype engine as a suitable candidate for replication. The frequency of the instability was 525 Hz, with an amplitude of approximately 1.5-psi peak-to-peak at a burner pressure of 200 psia. The single-nozzle experimental combustor rig was designed to preserve subcomponent lengths, cross sectional area distribution, flow distribution, pressure-drop distribution, temperature distribution, and other factors previously found to be determinants of burner acoustic frequencies, mode shapes, gain, and damping. Analytical models were used to predict the acoustic resonances of both the engine combustor and proposed experiment. The analysis confirmed that the test rig

  3. Integrated CFD modeling of gas turbine combustors

    NASA Technical Reports Server (NTRS)

    Fuller, E. J.; Smith, C. E.

    1993-01-01

    3D, curvilinear, multi-domain CFD analysis is becoming a valuable tool in gas turbine combustor design. Used as a supplement to experimental testing. CFD analysis can provide improved understanding of combustor aerodynamics and used to qualitatively assess new combustor designs. This paper discusses recent advancements in CFD combustor methodology, including the timely integration of the design (i.e. CAD) and analysis (i.e. CFD) processes. Allied Signal's F124 combustor was analyzed at maximum power conditions. The assumption of turbulence levels at the nozzle/swirler inlet was shown to be very important in the prediction of combustor exit temperatures. Predicted exit temperatures were compared to experimental rake data, and good overall agreement was seen. Exit radial temperature profiles were well predicted, while the predicted pattern factor was 25 percent higher than the harmonic-averaged experimental pattern factor.

  4. Design of Combustor for Long-range Ram-jet Engine and Performance of Rectangular Analog

    NASA Technical Reports Server (NTRS)

    Rayle, Warren D; Koch, Richard G

    1954-01-01

    The report describes the design of a piloted combustor intended for a ram-jet engine of long flight range. The unit comprises a large annular basket of V-type cross-section, the inner surface of which is slotted and bent into small V-gutters. At the trailing edge of the basket, eight V-gutters are used to propagate the flame into the main stream. A rectangular analog of this combustor was tested at air-flow conditions corresponding to those that might be obtained during cruise. At these conditions, combustion efficiencies of as much as 90 percent were calculated for the combustor at the design equivalence ratio of 0.52. The performance of the unit was relatively insensitive to mounting and flow variables; the greatest effect on efficiency was that of the manner and location of the fuel injection. A full-scale version of this combustor has been designed for a 48-inch-diameter engine.

  5. Design and Evaluation of a Single-Inlet Pulse Detonation Combustor

    DTIC Science & Technology

    2011-06-01

    Kilogram/second m/s Meters/ second N Nitrogen NPS Naval Postgraduate School O Oxygen PDC Pulse Detonation Combustion PDE Pulse Detonation Engine...EVALUATION OF A SINGLE-INLET PULSE DETONATION COMBUSTOR by Danny Soria June 2011 Thesis Advisor: Christopher M. Brophy Second Reader: Garth V...COVERED Master’s Thesis 4. TITLE AND SUBTITLE Design and Evaluation of a Single-Inlet Pulse Detonation Combustor 6. AUTHOR(S) Danny Soria 5

  6. Experimental clean combustor program, phase 2

    NASA Technical Reports Server (NTRS)

    Gleason, C. C.; Rogers, D. W.; Bahr, D. W.

    1976-01-01

    The primary objectives of this three-phase program are to develop technology for the design of advanced combustors with significantly lower pollutant emission levels than those of current combustors, and to demonstrate these pollutant emission reductions in CF6-50C engine tests. The purpose of the Phase 2 Program was to further develop the two most promising concepts identified in the Phase 1 Program, the double annular combustor and the radial/axial staged combustor, and to design a combustor and breadboard fuel splitter control for CF6-50 engine demonstration testing in the Phase 3 Program. Noise measurement and alternate fuels addendums to the basic program were conducted to obtain additional experimental data. Twenty-one full annular and fifty-two sector combustor configurations were evaluated. Both combustor types demonstrated the capability for significantly reducing pollutant emission levels. The most promising results were obtained with the double annular combustor. Rig test results corrected to CF-50C engine conditions produced EPA emission parameters for CO, HC, and NOX of 3.4, 0.4, and 4.5 respectively. These levels represent CO, HC, and NOX reductions of 69, 90, and 42 percent respectively from current combustor emission levels. The combustor also met smoke emission level requirements and development engine performance and installation requirements.

  7. A Design Methodology for Rapid Implementation of Active Control Systems Across Lean Direct Injection Combustor Platforms

    NASA Technical Reports Server (NTRS)

    Baumann, William T.; Saunders, William R.; Vandsburger, Uri; Saus, Joseph (Technical Monitor)

    2003-01-01

    The VACCG team is comprised of engineers at Virginia Tech who specialize in the subject areas of combustion physics, chemical kinetics, dynamics and controls, and signal processing. Currently, the team's work on this NRA research grant is designed to determine key factors that influence combustion control performance through a blend of theoretical and experimental investigations targeting design and demonstration of active control for three different combustors. To validiate the accuracy of conclusions about control effectiveness, a sequence of experimental verifications on increasingly complex lean, direct injection combustors is underway. During the work period January 1, 2002 through October 15, 2002, work has focused on two different laboratory-scale combustors that allow access for a wide variety of measurements. As the grant work proceeds, one key goal will be to obtain certain knowledge about a particular combustor process using a minimum of sophisticated measurements, due to the practical limitations of measurements on full-scale combustors. In the second year, results obtained in the first year will be validated on test combustors to be identified in the first quarter of that year. In the third year, it is proposed to validate the results at more realistic pressure and power levels by utilizing the facilities at the Glenn Research Center.

  8. Optical Fuel Injector Patternation Measurements in Advanced Liquid-Fueled, High Pressure, Gas Turbine Combustors

    NASA Technical Reports Server (NTRS)

    Locke, R. J.; Hicks, Y. R.; Anderson, R. C.; Zaller, M. M.

    1998-01-01

    Planar laser-induced fluorescence (PLIF) imaging and planar Mie scattering are used to examine the fuel distribution pattern (patternation) for advanced fuel injector concepts in kerosene burning, high pressure gas turbine combustors. Three fuel injector concepts for aerospace applications were investigated under a broad range of operating conditions. Fuel PLIF patternation results are contrasted with those obtained by planar Mie scattering. For one injector, further comparison is also made with data obtained through phase Doppler measurements. Differences in spray patterns for diverse conditions and fuel injector configurations are readily discernible. An examination of the data has shown that a direct determination of the fuel spray angle at realistic conditions is also possible. The results obtained in this study demonstrate the applicability and usefulness of these nonintrusive optical techniques for investigating fuel spray patternation under actual combustor conditions.

  9. Pylon Fuel Injector Design for a Scramjet Combustor (Postprint)

    DTIC Science & Technology

    2007-07-01

    Combustor by Application of Laser Diagnostics,” AIAA Paper 2002-5203, Oct. 2002. 22Sunami, T., Magre, P., Bresson , A., Grisch, F., Orain, M., and Kodera, M...Asymmetric Nozzles,” AIAA Paper 96-0200, Jan. 1996. 25Haimovitch, Y., Gartenberg, E., Roberts , A., and Northam, G., “Effects of Internal Nozzle

  10. Preliminary operating assessment advanced Heat Recovery Incinerator (HRI). Site One: O'Connor Combustor Corporation

    NASA Astrophysics Data System (ADS)

    Hollander, H. I.; Matzuk, G. J.; Romine, G.

    1983-07-01

    This brief evaluation of the first O'Connor (rotary waterwell) Combustor plant built in the U.S.A. describes design features and considerations as well as initial operating advantages and difficulties. A brief general description of a co-located, proprietary fuel preparation system is included. The major conclusion presented alludes to a waste fuel availability requirement approaching 60 tons per day (tpd) for probable cost-effectiveness of this technology.

  11. Experimental evaluation of combustor concepts for burning broad property fuels

    NASA Technical Reports Server (NTRS)

    Kasper, J. M.; Ekstedt, E. E.; Dodds, W. J.; Shayeson, M. W.

    1980-01-01

    A baseline CF6-50 combustor and three advanced combustor designs were evaluated to determine the effects of combustor design on operational characteristics using broad property fuels. Three fuels were used in each test: Jet A, a broad property 13% hydrogen fuel, and a 12% hydrogen fuel blend. Testing was performed in a sector rig at true cruise and simulated takeoff conditions for the CF6-50 engine cycle. The advanced combustors (all double annular, lean dome designs) generally exhibited lower metal temperatures, exhaust emissions, and carbon buildup than the baseline CF6-50 combustor. The sensitivities of emissions and metal temperatures to fuel hydrogen content were also generally lower for the advanced designs. The most promising advanced design used premixing tubes in the main stage. This design was chosen for additional testing in which fuel/air ratio, reference velocity, and fuel flow split were varied.

  12. Advanced oxide dispersion strengthened sheet alloys for improved combustor durability

    NASA Technical Reports Server (NTRS)

    Henricks, R. J.

    1981-01-01

    Burner design modifications that will take advantage of the improved creep and cyclic oxidation resistance of oxide dispersion strengthened (ODS) alloys while accommodating the reduced fatigue properties of these materials were evaluated based on preliminary analysis and life predictions, on construction and repair feasibility, and on maintenance and direct operating costs. Two designs - the film cooled, segmented louver and the transpiration cooled, segmented twin Wall - were selected for low cycle fatigue (LCF) component testing. Detailed thermal and structural analysis of these designs established the strain range and temprature at critical locations resulting in predicted lives of 10,000 cycles for MA 956 alloy. The ODs alloys, MA 956 and HDA 8077, demonstrated a 167 C (300 F) temperature advantage over Hastelloy X alloy in creep strength and oxidation resistance. The MA 956 alloy was selected for mechanical property and component test evaluations. The MA 956 alloy was superior to Hastelloy X in LCF component testing of the film cooled, segmented louver design.

  13. Combustion of high-sulfur coal and anthracite wastes in a rotary kiln combustor with an advanced internal air distributor

    SciTech Connect

    Cobb, J.T. Jr. ); Ahn, Y.K. ); Angelo, J.F. )

    1990-01-01

    Fluid bed combustors have received extensive testing with both high-sulfur coal and anthracite wastes. Rotary kilns are effective and popular devices for waste combustion. The Angelo Rotary Furnace{trademark} has been developed to improve the operation of rotary pyrolyzer/combustor systems through enhanced air distribution, which in this process is defined as staged, swirled combustion air injection. Fourteen of these new furnaces have been installed worldwide. Two units in Thailand, designed for rice hull feed with occasional lignite feed, have been recently started up. An older unit in Pennsylvania is being upgraded with a new, more advanced air distribution system for a series of tests this fall in which inexpensive high-sulfur coal and anthracite wastes will be fired with limestone. The purposes of these tests are to determine the burning characteristics of these two fuels in this system, to discover the Ca/S ratios necessary for operation of a rotary kiln combusting these fuels, and to observe the gas-borne emissions from the furnace. An extensive preliminary design study will be performed on a commercial installation for combustion of anthracite wastes. 14 refs., 5 figs., 1 tab.

  14. Design and evaluation of combustors for reducing aircraft engine pollution

    NASA Technical Reports Server (NTRS)

    Jones, R. E.; Grobman, J.

    1973-01-01

    Efforts in reducing exhaust emissions from turbine engines are reported. Various techniques employed and the results of testing are briefly described and referenced for detail. The experimental approaches taken to reduce oxides of nitrogen emissions include the use of: (1) multizone combustors incorporating reduced dwell times, (2) fuel-air premixing, (3) air atomization, (4) fuel prevaporization, and (5) gaseous fuel. Since emissions of unburned hydrocarbons and carbon monoxide are caused by poor combustion efficiency at engine idle, the studies of fuel staging in multizone combustors and air assist fuel nozzles have indicated that large reductions in these emissions can be achieved. Also, the effect of inlet-air humidity on oxides of nitrogen was studied as well as the very effective technique of direct water injection. The emission characteristics of natural gas and propane fuels were measured and compared with those of ASTM-Al kerosene fuel.

  15. Advanced low-NO(x) combustors for supersonic high-altitude gas turbines

    NASA Technical Reports Server (NTRS)

    Roberts, P. B.

    1977-01-01

    The impact of gas-turbine-engine-powered aircraft on worldwide pollution was defined within two major areas of contribution. First, the contribution of aircraft to the local air pollution of metropolitan areas and, second, the long-term effects on the chemical balance of the stratosphere of pollutants emitted from future generations of high-altitude, supersonic commercial and military aircraft. Preliminary findings indicate that stratospheric oxides of nitrogen (NOx) emissions may have to be limited to very low levels if, for example, ozone depletion with concomitant increases in sea-level radiation, are to be avoided. Theoretical considerations suggest that (NOx) levels as low as 1.0 gram per kilogram of fuel and less should be attainable from a idealized premixed type of combustor. Experimental rig studies were intended to explore new combustor concepts designed to minimize the formation of (NOx) in aircraft gas turbines and to define their major operational problems and limitations.

  16. High-temperature durability considerations for HSCT combustor

    NASA Technical Reports Server (NTRS)

    Jacobson, Nathan S.

    1992-01-01

    The novel combustor designs for the High Speed Civil Transport will require high temperature materials with long term environmental stability. Higher liner temperatures than in conventional combustors and the need for reduced weight necessitates the use of advanced ceramic matrix composites. The combustor environment is defined at the current state of design, the major degradation routes are discussed for each candidate ceramic material, and where possible, the maximum use temperatures are defined for these candidate ceramics.

  17. Design and Performance of a Low Btu Fuel Rich-Quench-Lean Gas Turbine Combustor

    SciTech Connect

    Feitelberg, A.S.; Jackson, M.R.; Lacey, M.A.; Manning, K.S.; Ritter, A.M.

    1996-12-31

    General Electric Company is developing gas turbines and a high temperature desulfurization system for use in integrated gasification combined cycle (IGCC) power plants. High temperature desulfurization, or hot gas cleanup (HGCU), offers many advantages over conventional low temperature desulfurization processes, but does not reduce the relatively high concentrations of fuel bound nitrogen (FBN) that are typically found in low Btu fuel. When fuels containing bound nitrogen are burned in conventional gas turbine combustors, a significant portion of the FBN is converted to NO{sub x}. Methods of reducing the NO{sub x} emissions from IGCC power plants equipped with HGCU are needed. Rich-quench-lean (RQL) combustion can decrease the conversion of FBN to NO{sub x} because a large fraction of the FBN is converted into non-reactive N{sub 2} in a fuel rich stage. Additional air, required for complete combustion, is added in a quench stage. A lean stage provides sufficient residence time for complete combustion. Objectives General Electric has developed and tested a rich-quench-lean gas turbine combustor for use with low Btu fuels containing FBN. The objective of this work has been to design an RQL combustor that has a lower conversion of FBN to N{sub x} than a conventional low Btu combustor and is suitable for use in a GE heavy duty gas turbine. Such a combustor must be of appropriate size and scale, configuration (can-annular), and capable of reaching ``F`` class firing conditions (combustor exit temperature = 2550{degrees}F).

  18. Recent advances in combustion flow-field imaging measurements in high-pressure liquid-fueled gas turbine combustor concepts

    NASA Astrophysics Data System (ADS)

    Locke, Randy J.; Hicks, Yolanda R.; Zaller, Michelle M.; Anderson, Robert C.

    1999-12-01

    Future gas turbine combustor designs for aerospace applications will be required to meet severe restrictions on environmentally harmful emissions. To meet the target emission reduction goals, these combustors will operate at temperatures and pressures greatly exceeding those of present day aero-powerplants. New diagnostic methods are required to provide insight into understanding the complex physical and chemical processes extant at these conditions because traditional diagnostic methods are either insufficient or incapable of providing this knowledge. At NASA Glenn Research Center (GRC), several optically accessible combustor rigs have been built which allow the implementation of a suite of optical diagnostic techniques that are capable of providing just this type of crucial information. The techniques employed in the GRC combustion research laboratory include planar laser-induced fluorescence and planar Mie scattering. Research efforts have been quite successful probing both non-reacting and reacting flowfields of many kerosene-fueled combustor and combustor subcomponent design at pressures approaching 2.0 MPa, and temperatures near 2100 K. Images that map out combustion intermediate species such as OH distribution, fuel spray patternation, and fuel to air ratio contour mapping have been obtained for many different fuel injector designs and configurations. A novel combination of multiple planar images and computational analysis allows a 3D capability that greatly enhances the evaluation of the combustion processes and flowfields examined in this study.

  19. User's manual for rocket combustor interactive design (ROCCID) and analysis computer program. Volume 1: User's manual

    NASA Technical Reports Server (NTRS)

    Muss, J. A.; Nguyen, T. V.; Johnson, C. W.

    1991-01-01

    The user's manual for the rocket combustor interactive design (ROCCID) computer program is presented. The program, written in Fortran 77, provides a standardized methodology using state of the art codes and procedures for the analysis of a liquid rocket engine combustor's steady state combustion performance and combustion stability. The ROCCID is currently capable of analyzing mixed element injector patterns containing impinging like doublet or unlike triplet, showerhead, shear coaxial, and swirl coaxial elements as long as only one element type exists in each injector core, baffle, or barrier zone. Real propellant properties of oxygen, hydrogen, methane, propane, and RP-1 are included in ROCCID. The properties of other propellants can easily be added. The analysis model in ROCCID can account for the influence of acoustic cavities, helmholtz resonators, and radial thrust chamber baffles on combustion stability. ROCCID also contains the logic to interactively create a combustor design which meets input performance and stability goals. A preliminary design results from the application of historical correlations to the input design requirements. The steady state performance and combustion stability of this design is evaluated using the analysis models, and ROCCID guides the user as to the design changes required to satisfy the user's performance and stability goals, including the design of stability aids. Output from ROCCID includes a formatted input file for the standardized JANNAF engine performance prediction procedure.

  20. Noise addendum experimental clean combustor program, phase 1

    NASA Technical Reports Server (NTRS)

    Sofrin, T. G.; Ross, D. A.

    1975-01-01

    The development of advanced CTOL aircraft engines with reduced exhaust emissions is discussed. Combustor noise information provided during the basic emissions program and used to advantage in securing reduced levels of combustion noise is included. Results are presented of internal pressure transducer measurements made during the scheduled emissions test program on ten configurations involving variations of three basic combustor designs.

  1. Emissions reduction by varying the swirler airflow split in advanced gas turbine combustors

    NASA Technical Reports Server (NTRS)

    Micklow, Gerald J.; Roychoudhury, Subir; Nguyen, H. L.; Cline, Michael C.

    1992-01-01

    A rich burn/quick mix/lean burn (RQL) combustor concept for reducing pollutant emissions is currently under investigation at the NASA Lewis Research Center. The current study investigates the effect of varying the mass flow rate split between the swirler passages for an equivalance ratio of 2.0 on fuel distribution, temperature distribution, and emissions for the fuel nozzle/rich burn section of an RQL combustor. It is seen that optimizing these parameters can substantially improve combustor performance and reduce combustor emissions. The optimal mass flow rate split for reducing NO(x) emissions based on the numerical study was the same as found by experiment.

  2. Final analysis and design of a thermal protection system for 8-foot HTST combustor

    NASA Technical Reports Server (NTRS)

    Moskowitz, S.

    1973-01-01

    The cylindrical shell combustor with T-bar supports in the 8-foot HTST at the NASA-Langley Research Center encountered vibratory fatigue cracking over a period of 50-250 tunnel tests within a limited range of the required operating envelope. A preliminary design study provided several suitable thermal protection system designs for the combustor, one of which was a two-pass regenerative type air-cooled omega-shaped segment liner. A final design layout of the omega segment liner was prepared and analyzed for steady-state and transient conditions. The design of a support system for the fuel spray bar assembly was also included. Detail drawings suitable for fabrication purposes were also prepared. Liner design problems defined during the preliminary study included (1) the ingress of gas into the attachment bulb section of the omega segment, (2) the large thermal gradient along the leg of the omega bulb attachment section and, (3) the local peak metal temperature at the radius between the liner ID and the leg of the bulb attachment. These were resolved during the final design task. Analyses of the final design of the omega segment liner indicated that all design goals were met and the design provided the capability of operating over the required test envelope with a life expectancy substantially above the goal of 1500 cycles.

  3. Energy efficient engine pin fin and ceramic composite segmented liner combustor sector rig test report

    NASA Technical Reports Server (NTRS)

    Dubiel, D. J.; Lohmann, R. P.; Tanrikut, S.; Morris, P. M.

    1986-01-01

    Under the NASA-sponsored Energy Efficient Engine program, Pratt and Whitney has successfully completed a comprehensive test program using a 90-degree sector combustor rig that featured an advanced two-stage combustor with a succession of advanced segmented liners. Building on the successful characteristics of the first generation counter-parallel Finwall cooled segmented liner, design features of an improved performance metallic segmented liner were substantiated through representative high pressure and temperature testing in a combustor atmosphere. This second generation liner was substantially lighter and lower in cost than the predecessor configuration. The final test in this series provided an evaluation of ceramic composite liner segments in a representative combustor environment. It was demonstrated that the unique properties of ceramic composites, low density, high fracture toughness, and thermal fatigue resistance can be advantageously exploited in high temperature components. Overall, this Combustor Section Rig Test program has provided a firm basis for the design of advanced combustor liners.

  4. Small Gas Turbine Combustor Primary Zone Study

    NASA Technical Reports Server (NTRS)

    Sullivan, R. E.; Young, E. R.; Miles, G. A.; Williams, J. R.

    1983-01-01

    A development process is described which consists of design, fabrication, and preliminary test evaluations of three approaches to internal aerodynamic primary zone flow patterns: (1) conventional double vortex swirl stabilization; (2) reverse flow swirl stabilization; and (3) large single vortex flow system. Each concept incorporates special design features aimed at extending the performance capability of the small engine combustor. Since inherent geometry of these combustors result in small combustion zone height and high surface area to volume ratio, design features focus on internal aerodynamics, fuel placement, and advanced cooling. The combustors are evaluated on a full scale annular combustor rig. A correlation of the primary zone performance with the overall performance is accomplished using three intrusion type gas sampling probes located at the exit of the primary zone section. Empirical and numerical methods are used for designing and predicting the performance of the three combustor concepts and their subsequent modifications. The calibration of analytical procedures with actual test results permits an updating of the analytical design techniques applicable to small reverse flow annular combustors.

  5. Development of a combustor analytical design methodology for liquid rocket engines

    NASA Technical Reports Server (NTRS)

    Pieper, Jerry L.; Muss, Jeff

    1989-01-01

    The development of a user friendly computerized methodology for the design and analysis of liquid propellant rocket engine combustion chambers is described. An overview of the methodology, consisting of a computer program containing an appropriate modular assembly of existing industry wide performance and combustion stability models, is presented. These models are linked with an interactive front end processor enabling the user to define the performance and stability traits of an existing design (point analysis) or to create the essential design features of a combustor to meet specific performance goals and combustion stability (point design). Plans for demonstration and verification of this methodology are also presented. These plans include the creation of combustor designs using the methodology, together with predictions of the performance and combustion stability for each design. A verification test program of 26 hot fire tests with up to four designs created using this methodology is described. This testing is planned using LOX/RP-1 propellants with a thrust level of approx. 220,000 N (50,000 lbf).

  6. Combustor design tool for a gas fired thermophotovoltaic energy converter

    SciTech Connect

    Lindler, K.W.; Harper, M.J.

    1995-07-01

    Recently, there has been a renewed interest in thermophotovoltaic (TPV) energy conversion. A TPV device converts radiant energy from a high temperature incandescent emitter directly into electricity by photovoltaic cells. The current Department of Energy sponsored research involves the design, construction and demonstration of a prototype TPV converter that uses a hydrocarbon fuel (such as natural gas) as the energy source. As the photovoltaic cells are designed to efficiently convert radiant energy at a prescribed wavelength, it is important that the temperature of the emitter be nearly constant over its entire surface. The US Naval Academy has been tasked with the development of a small emitter (with a high emissivity) that can be maintained at 1,756 K (2,700 F). This paper describes the computer spreadsheet model that was developed as a tool to be used for the design of the high temperature emitter.

  7. Design and fabrication of a meso-scale stirling engine and combustor.

    SciTech Connect

    Echekki, Tarek (Sandia National Laboratories, Livermore, CA); Haroldsen, Brent L. (Sandia National Laboratories, Livermore, CA); Krafcik, Karen L. (Sandia National Laboratories, Livermore, CA); Morales, Alfredo Martin; Mills, Bernice E.; Liu, Shiling; Lee, Jeremiah C. (Sandia National Laboratories, Livermore, CA); Karpetis, Adionos N. (Sandia National Laboratories, Livermore, CA); Chen, Jacqueline H. (Sandia National Laboratories, Livermore, CA); Ceremuga, Joseph T. (Sandia National Laboratories, Livermore, CA); Raber, Thomas N.; Hekmuuaty, Michelle A.

    2005-05-01

    Power sources capable of supplying tens of watts are needed for a wide variety of applications including portable electronics, sensors, micro aerial vehicles, and mini-robotics systems. The utility of these devices is often limited by the energy and power density capabilities of batteries. A small combustion engine using liquid hydrocarbon fuel could potentially increase both power and energy density by an order of magnitude or more. This report describes initial development work on a meso-scale external combustion engine based on the Stirling cycle. Although other engine designs perform better at macro-scales, we believe the Stirling engine cycle is better suited to small-scale applications. The ideal Stirling cycle requires efficient heat transfer. Consequently, unlike other thermodynamic cycles, the high heat transfer rates that are inherent with miniature devices are an advantage for the Stirling cycle. Furthermore, since the Stirling engine uses external combustion, the combustor and engine can be scaled and optimized semi-independently. Continuous combustion minimizes issues with flame initiation and propagation. It also allows consideration of a variety of techniques to promote combustion that would be difficult in a miniature internal combustion engine. The project included design and fabrication of both the engine and the combustor. Two engine designs were developed. The first used a cylindrical piston design fabricated with conventional machining processes. The second design, based on the Wankel rotor geometry, was fabricated by through-mold electroforming of nickel in SU8 and LIGA micromolds. These technologies provided the requisite precision and tight tolerances needed for efficient micro-engine operation. Electroformed nickel is ideal for micro-engine applications because of its high strength and ductility. A rotary geometry was chosen because its planar geometry was more compatible with the fabrication process. SU8 lithography provided rapid

  8. Energy efficient engine sector combustor rig test program

    NASA Technical Reports Server (NTRS)

    Dubiel, D. J.; Greene, W.; Sundt, C. V.; Tanrikut, S.; Zeisser, M. H.

    1981-01-01

    Under the NASA-sponsored Energy Efficient Engine program, Pratt & Whitney Aircraft has successfully completed a comprehensive combustor rig test using a 90-degree sector of an advanced two-stage combustor with a segmented liner. Initial testing utilized a combustor with a conventional louvered liner and demonstrated that the Energy Efficient Engine two-stage combustor configuration is a viable system for controlling exhaust emissions, with the capability to meet all aerothermal performance goals. Goals for both carbon monoxide and unburned hydrocarbons were surpassed and the goal for oxides of nitrogen was closely approached. In another series of tests, an advanced segmented liner configuration with a unique counter-parallel FINWALL cooling system was evaluated at engine sea level takeoff pressure and temperature levels. These tests verified the structural integrity of this liner design. Overall, the results from the program have provided a high level of confidence to proceed with the scheduled Combustor Component Rig Test Program.

  9. Fuel Injector Patternation Evaluation in Advanced Liquid-Fueled, High Pressure, Gas Turbine Combustors, Using Nonintrusive Optical Diagnostic Techniques

    NASA Technical Reports Server (NTRS)

    Locke, R. J.; Hicks, Y. R.; Anderson, R. C.; Zaller, M. M.

    1998-01-01

    Planar laser-induced fluorescence (PLIF) imaging and planar Mie scattering are used to examine the fuel distribution pattern (patternation) for advanced fuel injector concepts in kerosene burning, high pressure gas turbine combustors. Three diverse fuel injector concepts for aerospace applications were investigated under a broad range of operating conditions. Fuel PLIF patternation results are contrasted with those obtained by planar Mie scattering. Further comparison is also made for one injector with data obtained through phase Doppler measurements. Differences in spray patterns for diverse conditions and fuel injector configurations are readily discernible. An examination of the data has shown that a direct determination of the fuel spray angle at realistic conditions is also possible. The results obtained in this study demonstrate the applicability and usefulness of these nonintrusive optical techniques for investigating fuel spray patternation under actual combustor conditions.

  10. Design Considerations of ISTAR Hydrocarbon Fueled Combustor Operating in Air Augmented Rocket, Ramjet and Scramjet Modes

    NASA Technical Reports Server (NTRS)

    Andreadis, Dean; Drake, Alan; Garrett, Joseph L.; Gettinger, Christopher D.; Hoxie, Stephen S.

    2003-01-01

    The development and ground test of a rocket-based combined cycle (RBCC) propulsion system is being conducted as part of the NASA Marshall Space Flight Center (MSFC) Integrated System Test of an Airbreathing Rocket (ISTAR) program. The eventual flight vehicle (X-43B) is designed to support an air-launched self-powered Mach 0.7 to 7.0 demonstration of an RBCC engine through all of its airbreathing propulsion modes - air augmented rocket (AAR), ramjet (RJ), and scramjet (SJ). Through the use of analytical tools, numerical simulations, and experimental tests the ISTAR program is developing and validating a hydrocarbon-fueled RBCC combustor design methodology. This methodology will then be used to design an integrated RBCC propulsion system that produces robust ignition and combustion stability characteristics while maximizing combustion efficiency and minimizing drag losses. First order analytical and numerical methods used to design hydrocarbon-fueled combustors are discussed with emphasis on the methods and determination of requirements necessary to establish engine operability and performance characteristics.

  11. Design Considerations of Istar Hydrocarbon Fueled Combustor Operating in Air Augmented Rocket, Ramjet and Scramjet Modes

    NASA Technical Reports Server (NTRS)

    Andreadis, Dean; Drake, Alan; Garrett, Joseph L.; Gettinger, Christopher D.; Hoxie, Stephen S.

    2002-01-01

    The development and ground test of a rocket-based combined cycle (RBCC) propulsion system is being conducted as part of the NASA Marshall Space Flight Center (MSFC) Integrated System Test of an Airbreathing Rocket (ISTAR) program. The eventual flight vehicle (X-43B) is designed to support an air-launched self-powered Mach 0.7 to 7.0 demonstration of an RBCC engine through all of its airbreathing propulsion modes - air augmented rocket (AAR), ramjet (RJ), and scramjet (SJ). Through the use of analytical tools, numerical simulations, and experimental tests the ISTAR program is developing and validating a hydrocarbon-fueled RBCC combustor design methodology. This methodology will then be used to design an integrated RBCC propulsion system thai: produces robust ignition and combustion stability characteristics while maximizing combustion efficiency and minimizing drag losses. First order analytical and numerical methods used to design hydrocarbon-fueled combustors are discussed with emphasis on the methods and determination of requirements necessary to establish engine operability and performance characteristics.

  12. CFD Based Design of a Filming Injector for N+3 Combustors

    NASA Technical Reports Server (NTRS)

    Ajmani, Kumud; Mongia, Hukam; Lee, Phil

    2016-01-01

    An effort was undertaken to perform CFD analysis of fluid flow in Lean-Direct Injection (LDI) combustors with axial swirl-venturi elements for next-generation LDI-3 combustor design. The National Combustion Code (NCC) was used to perform non-reacting and two-phase reacting flow computations for a newly-designed pre-filming type fuel injector LDI-3 injector, in a single-injector and a five-injector array configuration. All computations were performed with a consistent approach of mesh-optimization, spray-modeling, ignition and kinetics-modeling. Computational predictions of the aerodynamics of the single-injector were used to arrive at an optimized main-injector design that meets effective area and fuel-air mixing criteria. Emissions (EINOx) characteristics were predicted for a medium-power engine cycle condition, and will be compared with data when it is made available from experimental measurements. The use of a PDF-like turbulence-chemistry interaction model with NCC's Time-Filtered Navier-Stokes (TFNS) solver is shown to produce a significant impact on the CFD results, when compared with a laminar-chemistry TFNS approach for the five-injector computations.

  13. INVESTIGATION OF HEAT TRANSFER AND COMBUSTION IN THE ADVANCED FLUIDIZED BED COMBUSTOR (FBC)

    SciTech Connect

    Dr. Seong W. Lee

    1998-04-01

    This technical report summarizes the research conducted and progress achieved during the period from January 1, 1998 to March 31, 1998. The systematic combustion tests were conducted to investigate the thermal performance and heat transfer effect of the exploratory hot model. The different ratios of the top to the bottom secondary air flow rate were chosen to study the effect of the secondary air flow rate. The test results indicated that the secondary air flow rate was a very sensitive factor to the combustion temperature profile. The heat transfer coefficients were changed along the combustor height. Numerical simulation was continued to determine the pressure profiles and temperature profiles in the hot combustor model. The pressure change at the bottom is greater than that of the top region because of a large amount of primary air input. The higher pressure zone is formed where the secondary air flows into the center region of the combustor. The high temperature zone of the bottom section is located at the fuel injector nozzle outlet. The lower temperature profiles were near the combustor wall because the cooling effect of the heat exchanger. The center temperature of the combustor at the upper secondary air nozzles is higher than that at the lower secondary air nozzles.

  14. Numerical simulation of the reactive flow in advanced (HSR) combustors using KIVA-2

    NASA Technical Reports Server (NTRS)

    Winowich, Nicholas S.

    1991-01-01

    Recent work has been done with the goal of establishing ultralow emission aircraft gas turbine combustors. A significant portion of the effort is the development of three dimensional computational combustor models. The KIVA-II computer code which is based on the Implicit Continuous Eulerian Difference mesh Arbitrary Lagrangian Eulerian (ICED-ALE) numerical scheme is one of the codes selected by NASA to achieve these goals. This report involves a simulation of jet injection through slanted slots within the Rich burn/Quick quench/Lean burn (RQL) baseline experimental rig. The RQL combustor distinguishes three regions of combustion. This work specifically focuses on modeling the quick quench mixer region in which secondary injection air is introduced radially through 12 equally spaced slots around the mixer circumference. Steady state solutions are achieved with modifications to the KIVA-II program. Work currently underway will evaluate thermal mixing as a function of injection air velocity and angle of inclination of the slots.

  15. Investigation of Heat Transfer and Combustion in the Advanced Fluidized Bed Combustor (FBC).

    SciTech Connect

    Lee, S.W.

    1997-04-01

    This technical report summarizes the research conducted and progress achieved during the period from January 1, 1997 to March 30, 1997. The systematic tests were conducted to investigate the thermal performance and heat transfer effect on the exploratory hot model. Test results were analyzed to understand thermal performance, heat balance, and heat transfer effect on exploratory hot model. Temperature was measured at different locations of the combustor chamber. The temperature was decreased along the increase the distance from the bottom of the combustor chamber. The heat loss from the combustor wall to the environment is a great portion of the total heat transfer. The flame enthalpy and heat loss at the reactor center changed along the reactor height. The heat loss into the cooling water for case A is about two times lager than that of case B. The heat transfer coefficient from gas to the environment increased as the flame temperature increased.

  16. Composite Matrix Experimental Combustor

    DTIC Science & Technology

    1994-04-01

    Preliminary (Macro) Combustor Design ............................. 28 4.1 Preliminary Design Study-Early Concept Combustion System ............. 28 4.2...provided in Appendix B. 4.1 PRELIMINARY DESIGN STUDY-EARLY CONCEPT COMBUSTION SYSTEM The preliminary design effort resulted in the selection of the early...overall flowpath. The concept I combustor is a compact, annular, reverse-flow design incorporating a single row of primary combustion air holes and a

  17. Fuel properties effect on the performance of a small high temperature rise combustor

    NASA Technical Reports Server (NTRS)

    Acosta, Waldo A.; Beckel, Stephen A.

    1989-01-01

    The performance of an advanced small high temperature rise combustor was experimentally determined at NASA-Lewis. The combustor was designed to meet the requirements of advanced high temperature, high pressure ratio turboshaft engines. The combustor featured an advanced fuel injector and an advanced segmented liner design. The full size combustor was evaluated at power conditions ranging from idle to maximum power. The effect of broad fuel properties was studied by evaluating the combustor with three different fuels. The fuels used were JP-5, a blend of Diesel Fuel Marine/Home Heating Oil, and a blend of Suntec C/Home Heating Oil. The fuel properties effect on the performance of the combustion in terms of pattern factor, liner temperatures, and exhaust emissions are documented.

  18. Development and testing of a high efficiency advanced coal combustor Phase III industrial boiler retrofit. Quarterly technical progress report, July 1, 1995--September 30, 1995 No. 16

    SciTech Connect

    Borio, R.W.

    1995-12-15

    The objective of this project is to retrofit a burner, capable of firing microfine coal, to a standard gas/oil designed industrial boiler to assess the technical and economic viability of displacing premium fuels with microfine coal. This report documents the technical aspects of this project during the sixteenth quarter (July `95 through September `95) of the program. The overall program has consisted of five major tasks: (1) A review of current state-of-the-art coal firing system components. (2) Design and experimental testing of a prototype HEACC (High Efficiency Advanced Coal Combustor) burner. (3) Installation and testing of a prototype HEACC system in a commercial retrofit application. (4) Economics evaluation of the HEACC concept for retrofit applications. (5) Long term demonstration under commercial user demand conditions.

  19. Design, Construction, and Validation of the AFIT Small Scale Combustion Facility and Sectional Model of the Ultra-Compact Combustor

    DTIC Science & Technology

    2007-03-01

    small-scale combustion experiments at atmospheric pressure . A sectional model of the Ultra-Compact Combustor has also been designed and built...Measurement .......................................................................... 22 Pressure Transducers and Thermocouples...3 Figure 2: Detail of UCC with RVC’s, this model was used in CFD research. (Greenwood, 2005:1-4

  20. Combustor technology for future small gas turbine aircraft

    NASA Technical Reports Server (NTRS)

    Lyons, Valerie J.; Niedzwiecki, Richard W.

    1994-01-01

    To enhance fuel efficiency, future advanced small gas turbine engines will utilize engine cycles calling for overall engine pressure ratios, leading to higher combustor inlet pressures and temperatures. Further, the temperature rise through the combustor and the corresponding exit temperature are also expected to increase. This report describes future combustor technology needs for small gas turbine engines. New fuel injectors with large turndown ratios which produce uniform circumferential and radial temperature patterns will be required. Uniform burning will be of greater importance because hot gas temperatures will approach turbine material limits. The higher combustion temperatures and increased radiation at high pressures will put a greater heat load on the combustor liners. At the same time, less cooling air will be available as more of the air will be used for combustion. Thus, improved cooling concepts and/or materials requiring little or no direct cooling will be required. Although presently there are no requirements for emissions levels from small gas turbine engines, regulation is anticipated in the near future. This will require the development of low emission combustors. In particular, nitrogen oxides will increase substantially if new technologies limiting their formation are not evolved and implemented. For example, staged combustion employing lean, premixed/prevaporized, lean direct injection, or rich burn-quick quench-lean burn concepts could replace conventional single stage combustors. Due to combustor size considerations, staged combustion is more easily accommodated in large engines. The inclusion of staged combustion in small engines will pose greater combustor design challenges.

  1. Combustor liner durability analysis

    NASA Technical Reports Server (NTRS)

    Moreno, V.

    1981-01-01

    An 18 month combustor liner durability analysis program was conducted to evaluate the use of advanced three dimensional transient heat transfer and nonlinear stress-strain analyses for modeling the cyclic thermomechanical response of a simulated combustor liner specimen. Cyclic life prediction technology for creep/fatigue interaction is evaluated for a variety of state-of-the-art tools for crack initiation and propagation. The sensitivity of the initiation models to a change in the operating conditions is also assessed.

  2. Computational models for the analysis/design of hypersonic scramjet components. I - Combustor and nozzle models

    NASA Technical Reports Server (NTRS)

    Dash, S. M.; Sinha, N.; Wolf, D. E.; York, B. J.

    1986-01-01

    An overview of computational models developed for the complete, design-oriented analysis of a scramjet propulsion system is provided. The modular approach taken involves the use of different PNS models to analyze the individual propulsion system components. The external compression and internal inlet flowfields are analyzed by the SCRAMP and SCRINT components discussed in Part II of this paper. The combustor is analyzed by the SCORCH code which is based upon SPLITP PNS pressure-split methodology formulated by Dash and Sinha. The nozzle is analyzed by the SCHNOZ code which is based upon SCIPVIS PNS shock-capturing methodology formulated by Dash and Wolf. The current status of these models, previous developments leading to this status, and, progress towards future hybrid and 3D versions are discussed in this paper.

  3. CFB combustor with internal solids recirculation -- Pilot testing and design applications

    SciTech Connect

    Belin, F.; Maryamchik, M.; Fuller, T.A.; Perna, M.A.

    1995-12-31

    The new generation of B and W`s CFB boilers with entirely internal recirculation of solids collected by the primary impact separator is uniquely compact and features a simple, low-maintenance solids collection system. Thorough testing of the new concept at the Cold CFB Model and the 2.5 MWth Pilot CFB combustor confirmed its effective performance equal to that of a CFB unit with external solids recirculation from the primary separator. While providing overall advantages of compactness and simplicity, the new design is especially valuable for repowering of the existing power plants where B and W`s CFB boiler fits into the plan area of PC-fired boilers.

  4. A conceptual design of shock-eliminating clover combustor for large scale scramjet engine

    NASA Astrophysics Data System (ADS)

    Sun, Ming-bo; Zhao, Yu-xin; Zhao, Guo-yan; Liu, Yuan

    2017-01-01

    A new concept of shock-eliminating clover combustor is proposed for large scale scramjet engine to fulfill the requirements of fuel penetration, total pressure recovery and cooling. To generate the circular-to-clover transition shape of the combustor, the streamline tracing technique is used based on an axisymmetric expansion parent flowfield calculated using the method of characteristics. The combustor is examined using inviscid and viscous numerical simulations and a pure circular shape is calculated for comparison. The results showed that the combustor avoids the shock wave generation and produces low total pressure losses in a wide range of flight condition with various Mach number. The flameholding device for this combustor is briefly discussed.

  5. The demonstration of an advanced cyclone coal combustor, with internal sulfur, nitrogen, and ash control for the conversion of a 23 MMBTU/hour oil fired boiler to pulverized coal

    SciTech Connect

    Zauderer, B.; Fleming, E.S.

    1991-08-30

    This work contains to the final report of the demonstration of an advanced cyclone coal combustor. Titles include: Chronological Description of the Clean Coal Project Tests,'' Statistical Analysis of Operating Data for the Coal Tech Combustor,'' Photographic History of the Project,'' Results of Slag Analysis by PA DER Module 1 Procedure,'' Properties of the Coals Limestone Used in the Test Effort,'' Results of the Solid Waste Sampling Performed on the Coal Tech Combustor by an Independent Contractor During the February 1990 Tests.'' (VC)

  6. A clean coal combustion technology-slagging combustors

    SciTech Connect

    Chang, S. L.; Berry, G. F.

    1989-03-01

    Slagging combustion is an advanced clean coal technology technique characterized by low NOx and SOx emission, high combustion efficiency, high ash removal, simple design and compact size. The design of slagging combustors has operational flexibility for a wide range of applications, including retrofitting boilers, magnetohydrodynamic combustors, coal-fired gas turbines, gasifiers and hazardous waste incinerators. In recent years, developers of slagging combustors have achieved encouraging progress toward the commercialization of this technology. Although there is a diversity of technical approaches among the developers, they all aim for a compact design of pulverized coal combustion with high heat release and sub-stoichiometric combustion regimes of operation to suppress NOx formation, and most aim to capture sulfur by using sorbent injection in the combustor. If the present pace toward commercialization continues, retrofitting boilers of sizes ranging from 20 to 250 MMBtu/hr (5.9 to 73 MWt) may be available for commercial use in the 1990's. 18 refs., 2 figs.

  7. A Comparison of Combustor-Noise Models

    NASA Technical Reports Server (NTRS)

    Hultgren, Lennart S.

    2012-01-01

    The present status of combustor-noise prediction in the NASA Aircraft Noise Prediction Program (ANOPP)1 for current-generation (N) turbofan engines is summarized. Several semi-empirical models for turbofan combustor noise are discussed, including best methods for near-term updates to ANOPP. An alternate turbine-transmission factor2 will appear as a user selectable option in the combustor-noise module GECOR in the next release. The three-spectrum model proposed by Stone et al.3 for GE turbofan-engine combustor noise is discussed and compared with ANOPP predictions for several relevant cases. Based on the results presented herein and in their report,3 it is recommended that the application of this fully empirical combustor-noise prediction method be limited to situations involving only General-Electric turbofan engines. Long-term needs and challenges for the N+1 through N+3 time frame are discussed. Because the impact of other propulsion-noise sources continues to be reduced due to turbofan design trends, advances in noise-mitigation techniques, and expected aircraft configuration changes, the relative importance of core noise is expected to greatly increase in the future. The noise-source structure in the combustor, including the indirect one, and the effects of the propagation path through the engine and exhaust nozzle need to be better understood. In particular, the acoustic consequences of the expected trends toward smaller, highly efficient gas-generator cores and low-emission fuel-flexible combustors need to be fully investigated since future designs are quite likely to fall outside of the parameter space of existing (semi-empirical) prediction tools.

  8. User's manual for rocket combustor interactive design (ROCCID) and analysis computer program. Volume 2: Appendixes A-K

    NASA Technical Reports Server (NTRS)

    Muss, J. A.; Nguyen, T. V.; Johnson, C. W.

    1991-01-01

    The appendices A-K to the user's manual for the rocket combustor interactive design (ROCCID) computer program are presented. This includes installation instructions, flow charts, subroutine model documentation, and sample output files. The ROCCID program, written in Fortran 77, provides a standardized methodology using state of the art codes and procedures for the analysis of a liquid rocket engine combustor's steady state combustion performance and combustion stability. The ROCCID is currently capable of analyzing mixed element injector patterns containing impinging like doublet or unlike triplet, showerhead, shear coaxial and swirl coaxial elements as long as only one element type exists in each injector core, baffle, or barrier zone. Real propellant properties of oxygen, hydrogen, methane, propane, and RP-1 are included in ROCCID. The properties of other propellants can be easily added. The analysis models in ROCCID can account for the influences of acoustic cavities, helmholtz resonators, and radial thrust chamber baffles on combustion stability. ROCCID also contains the logic to interactively create a combustor design which meets input performance and stability goals. A preliminary design results from the application of historical correlations to the input design requirements. The steady state performance and combustion stability of this design is evaluated using the analysis models, and ROCCID guides the user as to the design changes required to satisfy the user's performance and stability goals, including the design of stability aids. Output from ROCCID includes a formatted input file for the standardized JANNAF engine performance prediction procedure.

  9. Co-firing waste materials in an advanced pressurized fluidized-bed combustor

    SciTech Connect

    Rubow, L.N.; DeLallo, M.R.; Zaharchuk, R.

    1994-10-01

    A study has been undertaken to investigate the technical and economic feasibility of co-firing a pressurized fluidized-bed combustor (PFBC) with coal and municipal or industrial wastes. Focus was placed on the production of electricity and the efficient disposal of wastes for application in a central power station and distributed locations. Wastes considered for co-firing include municipal solid waste (MSW), municipal sewage sludge, and industrial de-inking sludge. Issues concerning waste material preparation and feed, PFBC operation, plant emissions, and regulations are addressed. This paper describes the results of the performance evaluation completed as part of this study, and provides recommendations for further evaluation.

  10. Transient catalytic combustor model

    NASA Technical Reports Server (NTRS)

    Tien, J. S.

    1981-01-01

    A quasi-steady gas phase and thermally thin substrate model is used to analyze the transient behavior of catalytic monolith combustors in fuel lean operation. The combustor response delay is due to the substrate thermal inertia. Fast response is favored by thin substrate, short catalytic bed length, high combustor inlet and final temperatures, and small gas channel diameters. The calculated gas and substrate temperature time history at different axial positions provides an understanding of how the catalytic combustor responds to an upstream condition change. The computed results also suggest that the gas residence times in the catalytic bed in the after bed space are correlatable with the nondimensional combustor response time. The model also performs steady state combustion calculations; and the computed steady state emission characteristics show agreement with available experimental data in the range of parameters covered. A catalytic combustor design for automotive gas turbine engine which has reasonably fast response ( 1 second) and can satisfy the emission goals in an acceptable total combustor length is possible.

  11. Transient catalytic combustor model

    NASA Astrophysics Data System (ADS)

    Tien, J. S.

    1981-05-01

    A quasi-steady gas phase and thermally thin substrate model is used to analyze the transient behavior of catalytic monolith combustors in fuel lean operation. The combustor response delay is due to the substrate thermal inertia. Fast response is favored by thin substrate, short catalytic bed length, high combustor inlet and final temperatures, and small gas channel diameters. The calculated gas and substrate temperature time history at different axial positions provides an understanding of how the catalytic combustor responds to an upstream condition change. The computed results also suggest that the gas residence times in the catalytic bed in the after bed space are correlatable with the nondimensional combustor response time. The model also performs steady state combustion calculations; and the computed steady state emission characteristics show agreement with available experimental data in the range of parameters covered. A catalytic combustor design for automotive gas turbine engine which has reasonably fast response ( 1 second) and can satisfy the emission goals in an acceptable total combustor length is possible.

  12. Flowpath Design of a Three-Tube Valve-Less Pulse Detonation Combustor

    DTIC Science & Technology

    2009-09-01

    geometry. 15. NUMBER OF PAGES 77 14. SUBJECT TERMS PDE Pulse Detonation Engine Side Dump Combustor Recirculation Zone 16. PRICE CODE 17...INTENTIONALLY LEFT BLANK 1 I. BACKGROUND A. INTRODUCTION Multi-tube Pulse Detonation Engines ( PDEs ) represent a significant opportunity for reducing...rocket, for example. PDE Envelope (representative) 3 B. ENGINE OPERATION PDEs , of which the Pulse Detonation Combustor is the operational core, are

  13. Durability testing at 5 atmospheres of advanced catalysts and catalyst supports for gas turbine engine combustors

    NASA Technical Reports Server (NTRS)

    Olson, B. A.; Lee, H. C.; Osgerby, I. T.; Heck, R. M.; Hess, H.

    1980-01-01

    The durability of CATCOM catalysts and catalyst supports was experimentally demonstrated in a combustion environment under simulated gas turbine engine combustor operating conditions. A test of 1000 hours duration was completed with one catalyst using no. 2 diesel fuel and operating at catalytically-supported thermal combustion conditions. The performance of the catalyst was determined by monitoring emissions throughout the test, and by examining the physical condition of the catalyst core at the conclusion of the test. Tests were performed periodically to determine changes in catalytic activity of the catalyst core. Detailed parametric studies were also run at the beginning and end of the durability test, using no. 2 fuel oil. Initial and final emissions for the 1000 hours test respectively were: unburned hydrocarbons (C3 vppm):0, 146, carbon monoxide (vppm):30, 2420; nitrogen oxides (vppm):5.7, 5.6.

  14. Flashback Arrestor for LPP, Low NOx Combustors

    NASA Technical Reports Server (NTRS)

    Kraemer, Gil; Lee, Chi-Ming

    1998-01-01

    Lean premixed, prevaporized (LPP) high temperature combustor designs as explored for the Advanced Subsonic Transport (AST) and High Speed Civil Transport (HSCT) combustors can achieve low NO(x), emission levels. An enabling device is needed to arrest flashback and inhibit preignition at high power conditions and during transients (surge and rapid spool down). A novel flashback arrestor design has demonstrated the ability to arrest flashback and inhibit preignition in a 4.6 cm diameter tubular reactor at full power inlet temperatures (725 C) using Jet-A fuel at 0.4 less than or equal To phi less than or equal to 3.5. Several low pressure loss (0.2 to 0.4% at 30 m/s) flashback arrestor designs were developed which arrested flashback at all of the test conditions. Flame holding was also inhibited off the flash arrestor face or within the downstream tube even velocities (less than or equal to 3 to 6 m/s), thus protecting the flashback arrestor and combustor components. Upstream flow conditions influence the specific configuration based on using either a 45% or 76% upstream geometric blockage. Stationary, lean premixed dry low NO(x) gas turbine combustors would also benefit from this low pressure drop flashback arrestor design which can be easily integrated into new and existing designs.

  15. Program user's manual for optimizing the design of a liquid or gaseous propellant rocket engine with the automated combustor design code AUTOCOM

    NASA Technical Reports Server (NTRS)

    Reichel, R. H.; Hague, D. S.; Jones, R. T.; Glatt, C. R.

    1973-01-01

    This computer program manual describes in two parts the automated combustor design optimization code AUTOCOM. The program code is written in the FORTRAN 4 language. The input data setup and the program outputs are described, and a sample engine case is discussed. The program structure and programming techniques are also described, along with AUTOCOM program analysis.

  16. Advanced solar panel designs

    NASA Technical Reports Server (NTRS)

    Ralph, E. L.; Linder, E.

    1995-01-01

    This paper describes solar cell panel designs that utilize new hgih efficiency solar cells along with lightweight rigid panel technology. The resulting designs push the W/kg and W/sq m parameters to new high levels. These new designs are well suited to meet the demand for higher performance small satellites. This paper reports on progress made on two SBIR Phase 1 contracts. One panel design involved the use of large area (5.5 cm x 6.5 cm) GaAs/Ge solar cells of 19% efficiency combined with a lightweight rigid graphite fiber epoxy isogrid substrate configuration. A coupon (38 cm x 38 cm) was fabricated and tested which demonstrated an array specific power level of 60 W/kg with a potential of reaching 80 W/kg. The second panel design involved the use of newly developed high efficiency (22%) dual junction GaInP2/GaAs/Ge solar cells combined with an advanced lightweight rigid substrate using aluminum honeycomb core with high strength graphite fiber mesh facesheets. A coupon (38 cm x 38 cm) was fabricated and tested which demonstrated an array specific power of 105 W/kg and 230 W/sq m. This paper will address the construction details of the panels and an a analysis of the component weights. A strawman array design suitable for a typical small-sat mission is described for each of the two panel design technologies being studied. Benefits in respect to weight reduction, area reduction, and system cost reduction are analyzed and compared to conventional arrays.

  17. Study of research and development requirements of small gas-turbine combustors

    NASA Technical Reports Server (NTRS)

    Demetri, E. P.; Topping, R. F.; Wilson, R. P., Jr.

    1980-01-01

    A survey is presented of the major small-engine manufacturers and governmental users. A consensus was undertaken regarding small-combustor requirements. The results presented are based on an evaluation of the information obtained in the course of the study. The current status of small-combustor technology is reviewed. The principal problems lie in liner cooling, fuel injection, part-power performance, and ignition. Projections of future engine requirements and their effect on the combustor are discussed. The major changes anticipated are significant increases in operating pressure and temperature levels and greater capability of using heavier alternative fuels. All aspects of combustor design are affected, but the principal impact is on liner durability. An R&D plan which addresses the critical combustor needs is described. The plan consists of 15 recommended programs for achieving necessary advances in the areas of liner thermal design, primary-zone performance, fuel injection, dilution, analytical modeling, and alternative-fuel utilization.

  18. Advanced turbocharger design study program

    NASA Technical Reports Server (NTRS)

    Culy, D. G.; Heldenbrand, R. W.; Richardson, N. R.

    1984-01-01

    The advanced Turbocharger Design Study consisted of: (1) the evaluation of three advanced engine designs to determine their turbocharging requirements, and of technologies applicable to advanced turbocharger designs; (2) trade-off studies to define a turbocharger conceptual design and select the engine with the most representative requirements for turbocharging; (3) the preparation of a turbocharger conceptual design for the Curtiss Wright RC2-32 engine selected in the trade-off studies; and (4) the assessment of market impact and the preparation of a technology demonstration plan for the advanced turbocharger.

  19. Quiet Clean Short-haul Experimental Engine (QCSEE). Double-annular clean combustor technology development report

    NASA Technical Reports Server (NTRS)

    Bahr, D. W.; Burrus, D. L.; Sabla, P. E.

    1979-01-01

    A sector combustor technology development program was conducted to define an advanced double annular dome combustor sized for use in the quiet clean short haul experimental engine (QCSEE). A design which meets the emission goals, and combustor performance goals of the QCSEE engine program was developed. Key design features were identified which resulted in substantial reduction in carbon monoxide and unburned hydrocarbon emission levels at ground idle operating conditions, in addition to very low nitric oxide emission levels at high power operating conditions. Their significant results are reported.

  20. Pollution technology program, can-annular combustor engines

    NASA Technical Reports Server (NTRS)

    Roberts, R.; Fiorentino, A. J.; Greene, W.

    1976-01-01

    A Pollution Reduction Technology Program to develop and demonstrate the combustor technology necessary to reduce exhaust emissions for aircraft engines using can-annular combustors is described. The program consisted of design, fabrication, experimental rig testing and assessment of results and was conducted in three program elements. The combustor configurations of each program element represented increasing potential for meeting the 1979 Environmental Protection Agency (EPA) emission standards, while also representing increasing complexity and difficulty of development and adaptation to an operational engine. Experimental test rig results indicate that significant reductions were made to the emission levels of the baseline JT8D-17 combustor by concepts in all three program elements. One of the Element I single-stage combustors reduced carbon monoxide to a level near, and total unburned hydrocarbons (THC) and smoke to levels below the 1979 EPA standards with little or no improvement in oxides of nitrogen. The Element II two-stage advanced Vorbix (vortex burning and mixing) concept met the standard for THC and achieved significant reductions in CO and NOx relative to the baseline. Although the Element III prevaporized-premixed concept reduced high power NOx below the Element II results, there was no improvement to the integrated EPA parameter relative to the Vorbix combustor.

  1. Combustor Design Criteria Validation. Volume I. Element Tests and Model Validation

    DTIC Science & Technology

    1979-03-01

    AiResearch ) in the design and development testing of a number of advanced combustion concepts . It is hoped that with continued improve- 4 ment in...This analytical procedure Is viewed as a significant step toward reducing the t design and development time and the cost associated with future Army...PA!,,b D the second concept required only one modification to meet the objectives. Therefore, the analytical models, when used in the proper context

  2. Development and testing of a high efficiency advanced coal combustor: Phase 3 -- Industrial boiler retrofit. Proof of concept testing summary (Task 3.0 Final topical report)

    SciTech Connect

    Patel, R.L.; Borio, R.; McGowan, J.G.

    1995-07-01

    Economics may one day dictate that it makes sense to replace oil or natural gas with coal in boilers that were originally designed to burn oil or gas. In recognition of this future possibility, Pittsburgh Energy Technical Center (PETC) has supported a program led by ABB Power Plant Laboratories in cooperation with the Energy and Fuels Research Center of Penn State University to develop the High Efficiency Advanced Coal Combustor (HEACC). The objective of the program is to demonstrate the technical and economic feasibility of retrofitting a gas/oil designed boiler to burn micronized coal. In support of the overall objective the following specific areas were targeted: a coal handling/preparation system that can meet the technical requirements for retrofitting microfine coal on a boiler designed for burning oil or natural gas; maintaining boiler thermal performance in accordance with specifications when burning oil or natural gas; maintaining NOx emissions at or below 0.6 lb NO{sub 2} per million Btu; achieving combustion efficiencies of 98% or higher; and calculating economic payback periods as a function of key variables. The work carried out under this program is broken into five major Tasks: review of current state-of-the-art coal firing system components; design and experimental testing of a prototype HEACC burner; installation and testing of a HEACC system in a retrofit application; economic evaluation of the HEACC concept for retrofit applications; and long term demonstration under user demand conditions. This report summarizes the work done under Task 3, the installation and testing of the HEACC burner in a 15,000 lb/hr package boiler located at Penn State. The period of testing was approximately 400 hours. Key findings are presented.

  3. Design and development test of a gas turbine combustor for air-blow Lurgi coal gas fuel

    SciTech Connect

    Beebe, K.W.; Ye, L.J.

    1985-01-01

    A heavy-duty industrial gas turbine combustion system has been designed and laboratory tested for use with low heating value coal gas produced by an air-blown Lurgi coal gasifier. The design fuel has a nominal lower heating value of 4.21 MJ/Nm/sup 3/ (107 BTU/SCF). The combustor design utilizes high-swirl fuel and air injection to provide rapid fuel/air mixing and a stable flame front, and is physically interchangeable with the conventional fuel combustion system for the General Electric Model MS5001 gas turbine. Full-pressure, full-scale tests of the new combustion system have been conducted at the General Electric Gas Turbine Development Laboratory in Schenectady, New York, USA, for the Shanghai Power Plant Equipment Research Institute (SPPERI) of the Peoples Republic of China. Simulated clean low heating value coal gas fuel with a composition specified by SPPERI was used for these tests. Laboratory test reults are presented for important combustor operating parameters, including exhaust emissions, combustion efficiency, exhaust temperature profile, dynamic pressure, and metal temperature distribution.

  4. HSCT Sector Combustor Evaluations for Demonstration Engine

    NASA Technical Reports Server (NTRS)

    Greenfield, Stuart; Heberling, Paul; Kastl, John; Matulaitis, John; Huff, Cynthia

    2004-01-01

    In LET Task 10, critical development issues of the HSCT lean-burn low emissions combustor were addressed with a range of engineering tools. Laser diagnostics and CFD analysis were applied to develop a clearer understanding of the fuel-air premixing process and premixed combustion. Subcomponent tests evaluated the emissions and operability performance of the fuel-air premixers. Sector combustor tests evaluated the performance of the integrated combustor system. A 3-cup sector was designed and procured for laser diagnostics studies at NASA Glenn. The results of these efforts supported the earlier selection of the Cyclone Swirler as the pilot stage premixer and the IMFH (Integrated Mixer Flame Holder) tube as the main stage premixer of the LPP combustor. In the combustor system preliminary design subtask, initial efforts to transform the sector combustor design into a practical subscale engine combustor met with significant challenges. Concerns about the durability of a stepped combustor dome and the need for a removable fuel injection system resulted in the invention and refinement of the MRA (Multistage Radial Axial) combustor system in 1994. The MRA combustor was selected for the HSR Phase II LPP subscale combustor testing in the CPC Program.

  5. Development and testing of a high efficiency advanced coal combustor: Phase 3, industrial boiler retrofit. Quarterly technical progress report number 12, July 1, 1994--September 30, 1994

    SciTech Connect

    Patel, R.L.; Borio, R.; McGowan, J.G.

    1994-11-18

    The objective of this project is to retrofit the previously developed High Efficiency Advanced Coal Combustor (HEACC) to a standard gas/oil designed industrial boiler to assess the technical and economic viability of displacing premium fuels with microfine coal. During this reporting period, data reduction/evaluation and interpretation from the long term four hundred hours Proof-of-Concept System Test under Task 3 were completed. Cumulatively, a total of approximately 563 hours of coal testing was performed with 160 hrs on 100% coal and over 400 hours with co-firing coal and gas. The primary objectives of this testing were to: (1) obtain steady state operation consistently on 100% coal; (2) increase carbon conversion efficiency from 95% to the project goal of 98%; and (3) maintain NOx emissions at or below 0.6 lbs/MBtu. The following specific conclusions are based on results of coal-fired testing at Penn State and the initial economic evaluation of the HEACC system: a coal handling/preparation system can be designed to meet the technical requirements for retrofitting microfine coal combustion to a gas/oil-designed boiler; the boiler thermal performance requirements were met; the NOx emission target of was met; combustion efficiencies of 95% could be met on a daily average basis, somewhat below the target of 98%; the economic playback is very sensitive to fuel differential cost, unit size, and annual operating hours; continuous long term demonstration is needed to quantify ash effects and how to best handle ashes. The following modifications are recommended prior to the 1,000 hour demonstration phase testing: (1) coal feeding improvements--improved raw coal/storage and transport, installation of gravimetric feeder, and redesign/installation of surge bin bottom; (2) burner modification--minor modification to the tip of the existing HEACC burner to prevent change of flame shapes for no apparent reason.

  6. Ceramic composite liner material for gas turbine combustors

    NASA Technical Reports Server (NTRS)

    Ercegovic, D. B.; Walker, C. L.; Norgren, C. T.

    1984-01-01

    Advanced commercial and military gas turbine engines may operate at combustor outlet temperatures in excess of 1920 K (3000 F). At these temperatures combustors liners experience extreme convective and radiative heat fluxes. The ability of a plasma sprayed ceramic coating to reduce liner metal temperature has been recognized. However, the brittleness of the ceramic layer and the difference in thermal expansion with the metal substrate has caused cracking, spalling and some separation of the ceramic coating. Research directed at turbine tip seals (or shrouds) has shown the advantage of applying the ceramic to a compliant metal pad. This paper discusses recent studies of applying ceramics to combustor liners in which yttria stabilized zirconia plasma sprayed on compliant metal substrates which were exposed to near stoichiometric combustion, presents performance and durability results, and describes a conceptual design for an advanced, small gas turbine combustor. Test specimens were convectively cooled or convective-transpiration cooled and were evaluated in a 10 cm square flame tube combustor at inlet air temperatures of 533 K (500 F) and at a pressure of 0.5 MPa (75 psia). The ceramics were exposed to flame temperatures in excess of 2000 K (3320 F). Results appear very promising with all 30 specimens surviving a screening test and one of two specimens surviving a cyclic durability test.

  7. Advanced hypersonic aircraft design

    NASA Technical Reports Server (NTRS)

    Utzinger, Rob; Blank, Hans-Joachim; Cox, Craig; Harvey, Greg; Mckee, Mike; Molnar, Dave; Nagy, Greg; Petersen, Steve

    1992-01-01

    The objective of this design project is to develop the hypersonic reconnaissance aircraft to replace the SR-71 and to complement existing intelligence gathering devices. The initial design considerations were to create a manned vehicle which could complete its mission with at least two airborne refuelings. The aircraft must travel between Mach 4 and Mach 7 at an altitude of 80,000 feet for a maximum range of 12,000 nautical miles. The vehicle should have an air breathing propulsion system at cruise. With a crew of two, the aircraft should be able to take off and land on a 10,000 foot runway, and the yearly operational costs were not to exceed $300 million. Finally, the aircraft should exhibit stealth characteristics, including a minimized radar cross-section (RCS) and a reduced sonic boom. The technology used in this vehicle should allow for production between the years 1993 and 1995.

  8. Design and Fabrication of the ISTAR Direct-Connect Combustor Experiment at the NASA Hypersonic Tunnel Facility

    NASA Technical Reports Server (NTRS)

    Lee, Jin-Ho; Krivanek, Thomas M.

    2005-01-01

    The Integrated Systems Test of an Airbreathing Rocket (ISTAR) project was a flight demonstration project initiated to advance the state of the art in Rocket Based Combined Cycle (RBCC) propulsion development. The primary objective of the ISTAR project was to develop a reusable air breathing vehicle and enabling technologies. This concept incorporated a RBCC propulsion system to enable the vehicle to be air dropped at Mach 0.7 and accelerated up to Mach 7 flight culminating in a demonstration of hydrocarbon scramjet operation. A series of component experiments was planned to reduce the level of risk and to advance the technology base. This paper summarizes the status of a full scale direct connect combustor experiment with heated endothermic hydrocarbon fuels. This is the first use of the NASA GRC Hypersonic Tunnel facility to support a direct-connect test. The technical and mechanical challenges involved with adapting this facility, previously used only in the free-jet configuration, for use in direct connect mode will be also described.

  9. Assessment, development, and application of combustor aerothermal models

    NASA Technical Reports Server (NTRS)

    Holdeman, J. D.; Mongia, H. C.; Mularz, E. J.

    1988-01-01

    The gas turbine combustion system design and development effort is an engineering exercise to obtain an acceptable solution to the conflicting design trade-offs between combustion efficiency, gaseous emissions, smoke, ignition, restart, lean blowout, burner exit temperature quality, structural durability, and life cycle cost. For many years, these combustor design trade-offs have been carried out with the help of fundamental reasoning and extensive component and bench testing, backed by empirical and experience correlations. Recent advances in the capability of computational fluid dynamcis codes have led to their application to complex 3-D flows such as those in the gas turbine combustor. A number of U.S. Government and industry sponsored programs have made significant contributions to the formulation, development, and verification of an analytical combustor design methodology which will better define the aerothermal loads in a combustor, and be a valuable tool for design of future combustion systems. The contributions made by NASA Hot Section Technology (HOST) sponsored Aerothermal Modeling and supporting programs are described.

  10. Assessment, development, and application of combustor aerothermal models

    NASA Technical Reports Server (NTRS)

    Holdeman, J. D.; Mongia, H. C.; Mularz, E. J.

    1989-01-01

    The gas turbine combustion system design and development effort is an engineering exercise to obtain an acceptable solution to the conflicting design trade-offs between combustion efficiency, gaseous emissions, smoke, ignition, restart, lean blowout, burner exit temperature quality, structural durability, and life cycle cost. For many years, these combustor design trade-offs have been carried out with the help of fundamental reasoning and extensive component and bench testing, backed by empirical and experience correlations. Recent advances in the capability of computational fluid dynamics codes have led to their application to complex 3-D flows such as those in the gas turbine combustor. A number of U.S. Government and industry sponsored programs have made significant contributions to the formulation, development, and verification of an analytical combustor design methodology which will better define the aerothermal loads in a combustor, and be a valuable tool for design of future combustion systems. The contributions made by NASA Hot Section Technology (HOST) sponsored Aerothermal Modeling and supporting programs are described.

  11. Assessment, development and application of combustor aerothermal models

    NASA Technical Reports Server (NTRS)

    Holdeman, J. D.; Mongia, H. C.; Mularz, E. J.

    1988-01-01

    The gas turbine combustion system design and development effort is an engineering exercise to obtain an acceptable solution to the conflicting design trade-offs between combustion efficiency, gaseous emissions, smoke, ignition, restart, lean blowout, burner exit temperature quality, structural durability, and life cycle cost. For many years, these combustor design trade-offs have been carried out with the help of fundamental reasoning and extensive component and bench testing, backed by empirical and experience correlations. Recent advances in the capability of computational fluid dynamics codes have led to their application to complex 3-D flows such as those in the gas turbine combustor. A number of U.S. Government and industry sponsored programs have made significant contributions to the formulation, development, and verification of an analytical combustor design methodology which will better define the aerothermal loads in a combustor, and be a valuable tool for design of future combustion systems. The contributions made by NASA Hot Section Technology (HOST) sponsored Aerothermal Modeling and supporting programs are described.

  12. Advanced hydrogen/oxygen thrust chamber design analysis

    NASA Technical Reports Server (NTRS)

    Shoji, J. M.

    1973-01-01

    The results are reported of the advanced hydrogen/oxygen thrust chamber design analysis program. The primary objectives of this program were to: (1) provide an in-depth analytical investigation to develop thrust chamber cooling and fatigue life limitations of an advanced, high pressure, high performance H2/O2 engine design of 20,000-pounds (88960.0 N) thrust; and (2) integrate the existing heat transfer analysis, thermal fatigue and stress aspects for advanced chambers into a comprehensive computer program. Thrust chamber designs and analyses were performed to evaluate various combustor materials, coolant passage configurations (tubes and channels), and cooling circuits to define the nominal 1900 psia (1.31 x 10 to the 7th power N/sq m) chamber pressure, 300-cycle life thrust chamber. The cycle life capability of the selected configuration was then determined for three duty cycles. Also the influence of cycle life and chamber pressure on thrust chamber design was investigated by varying in cycle life requirements at the nominal chamber pressure and by varying the chamber pressure at the nominal cycle life requirement.

  13. Analytical and experimental evaluations of the effect of broad property fuels on combustors for commercial aircraft gas turbine engines

    NASA Technical Reports Server (NTRS)

    Smith, A. L.

    1980-01-01

    The impacts of broad property fuels on the design, performance, durability, emissions, and operational characteristics of current and advanced combustors for commercial aircraft gas turbine engines were studied. The effect of fuel thermal stability on engine and airframe fuel system was evaluated. Tradeoffs between fuel properties, exhaust emissions, and combustor life were also investigated. Results indicate major impacts of broad property fuels on allowable metal temperatures in fuel manifolds and injector support, combustor cyclic durability, and somewhat lesser impacts on starting characteristics, lightoff, emissions, and smoke.

  14. Analytical fuel property effects--small combustors

    NASA Technical Reports Server (NTRS)

    Sutton, R. D.; Troth, D. L.; Miles, G. A.

    1984-01-01

    The consequences of using broad-property fuels in both conventional and advanced state-of-the-art small gas turbine combustors are assessed. Eight combustor concepts were selected for initial screening, of these, four final combustor concepts were chosen for further detailed analysis. These included the dual orifice injector baseline combustor (a current production 250-C30 engine combustor) two baseline airblast injected modifications, short and piloted prechamber combustors, and an advanced airblast injected, variable geometry air staged combustor. Final predictions employed the use of the STAC-I computer code. This quasi 2-D model includes real fuel properties, effects of injector type on atomization, detailed droplet dynamics, and multistep chemical kinetics. In general, fuel property effects on various combustor concepts can be classified as chemical or physical in nature. Predictions indicate that fuel chemistry has a significant effect on flame radiation, liner wall temperature, and smoke emission. Fuel physical properties that govern atomization quality and evaporation rates are predicted to affect ignition and lean-blowout limits, combustion efficiency, unburned hydrocarbon, and carbon monoxide emissions.

  15. Low NO(x) Combustor Development

    NASA Technical Reports Server (NTRS)

    Kastl, J. A.; Herberling, P. V.; Matulaitis, J. M.

    2005-01-01

    The goal of these efforts was the development of an ultra-low emissions, lean-burn combustor for the High Speed Civil Transport. The HSCT Mach 2.4 FLADE C1 Cycle was selected as the baseline engine cycle. A preliminary compilation of performance requirements for the HSCT combustor system was developed. The emissions goals of the program, baseline engine cycle, and standard combustor performance requirements were considered in developing the compilation of performance requirements. Seven combustor system designs were developed. The development of these system designs was facilitated by the use of spreadsheet-type models which predicted performance of the combustor systems over the entire flight envelope of the HSCT. A chemical kinetic model was developed for an LPP combustor and employed to study NO(x) formation kinetics, and CO burnout. These predictions helped to define the combustor residence time. Five fuel-air mixer concepts were analyzed for use in the combustor system designs. One of the seven system designs, one using the Swirl-Jet and Cyclone Swirler fuel-air mixers, was selected for a preliminary mechanical design study.

  16. Advanced Turbine Systems (ATS) program conceptual design and product development

    SciTech Connect

    1996-08-31

    Achieving the Advanced Turbine Systems (ATS) goals of 60% efficiency, single-digit NO{sub x}, and 10% electric power cost reduction imposes competing characteristics on the gas turbine system. Two basic technical issues arise from this. The turbine inlet temperature of the gas turbine must increase to achieve both efficiency and cost goals. However, higher temperatures move in the direction of increased NO{sub x} emission. Improved coatings and materials technologies along with creative combustor design can result in solutions to achieve the ultimate goal. GE`s view of the market, in conjunction with the industrial and utility objectives, requires the development of Advanced Gas Turbine Systems which encompass two potential products: a new aeroderivative combined-cycle system for the industrial market, and a combined-cycle system for the utility sector that is based on an advanced frame machine. The GE Advanced Gas Turbine Development program is focused on two specific products: (1) a 70 MW class industrial gas turbine based on the GE90 core technology utilizing an innovative air cooling methodology; (2) a 200 MW class utility gas turbine based on an advanced Ge heavy-duty machine utilizing advanced cooling and enhancement in component efficiency. Both of these activities required the identification and resolution of technical issues critical to achieving ATS goals. The emphasis for the industrial ATS was placed upon innovative cycle design and low emission combustion. The emphasis for the utility ATS was placed on developing a technology base for advanced turbine cooling, while utilizing demonstrated and planned improvements in low emission combustion. Significant overlap in the development programs will allow common technologies to be applied to both products. GE Power Systems is solely responsible for offering GE products for the industrial and utility markets.

  17. Challenges to Laser-Based Imaging Techniques in Gas Turbine Combustor Systems for Aerospace Applications

    NASA Technical Reports Server (NTRS)

    Locke, Randy J.; Anderson, Robert C.; Zaller, Michelle M.; Hicks, Yolanda R.

    1998-01-01

    Increasingly severe constraints on emissions, noise and fuel efficiency must be met by the next generation of commercial aircraft powerplants. At NASA Lewis Research Center (LeRC) a cooperative research effort with industry is underway to design and test combustors that will meet these requirements. To accomplish these tasks, it is necessary to gain both a detailed understanding of the combustion processes and a precise knowledge of combustor and combustor sub-component performance at close to actual conditions. To that end, researchers at LeRC are engaged in a comprehensive diagnostic investigation of high pressure reacting flowfields that duplicate conditions expected within the actual engine combustors. Unique, optically accessible flame-tubes and sector rig combustors, designed especially for these tests. afford the opportunity to probe these flowfields with the most advanced, laser-based optical diagnostic techniques. However, these same techniques, tested and proven on comparatively simple bench-top gaseous flame burners, encounter numerous restrictions and challenges when applied in these facilities. These include high pressures and temperatures, large flow rates, liquid fuels, remote testing, and carbon or other material deposits on combustor windows. Results are shown that document the success and versatility of these nonintrusive optical diagnostics despite the challenges to their implementation in realistic systems.

  18. Advances in robust flight design

    NASA Technical Reports Server (NTRS)

    Wong, Kelvin K.; Dhand, Sanjeev K.

    1991-01-01

    Current launch vehicle trajectory design philosophies, generally based on maximizing payload capability, result in an expensive and time-consuming iteration in trajectory design for each mission. However, for a launch system that is not performance-driven, a flight design that is robust to variations in missions and provides single-engine-out capability can be highly cost-effective. This philosophy has led to the development of two flight design concepts to reduce recurring costs: standard trajectories and command multiplier steering. Preliminary analyses of these two concepts had proven the feasibility and showed encouraging results in applications to an Advanced Launch System vehicle. Recent progress has demonstrated the effective and efficient integration of the two concepts with minimal payload penalty.

  19. Effect of fuel zoning and fuel nozzle design on pollution emissions at ground idle conditions for a double-annular ram-induction combustor

    NASA Technical Reports Server (NTRS)

    Clements, T. R.

    1973-01-01

    An exhaust emission survey was conducted on a double-annular ram induction combustor at simulated ground idle conditions. The combustor was designed for a large augmented turbofan engine capable of sustained flight speeds up to Mach 3.0. The emission levels of total hydrocarbon (THC), carbon monoxide, carbon dioxide, and nitric oxide were measured. The effects of fuel zoning, fuel nozzle design, and operating conditions (inlet temperature and reference Mach number) on the level of these emissions were determined. At an overall combustor fuel/air ratio of 0.007, fuel zoning reduced THC emissions by a factor of 5 to 1. The reduction in THC emissions is attributed to the increase in local fuel/air ratio provided by the fuel zoning. An alternative method of increasing fuel/air ratio would be to operate with larger-than-normal compressor overboard bleed; however, analysis on this method indicated an increase in idle fuel consumption of 20 percent. The use of air-atomizing nozzles reduced the THC emissions by 2 to 1.

  20. Advances in Ureteral Stent Design

    NASA Astrophysics Data System (ADS)

    Denstedt, John D.

    2007-04-01

    Ureteral stents are commonly used in urolithiasis patients for relief of obstruction or in association with stone treatments such as ureteroscopy and extracorporeal shock wave lithotripsy. There are currently many different bulk materials and coatings available for the manufacture of ureteral stents, however the ideal material has yet to be discovered. All potential biomaterials must undergo rigorous physical and biocompatibility testing before commercialization and use in humans. Despite significant advances in basic science research involving biocompatibility issues and biofilm formation, infection and encrustation remain associated with the use of biomaterials in the urinary tract. There have been many significant advances in the design of ureteral stents in recent years and these will be highlighted along with a discussion of future aspects of biomaterials and use of stents in association with urolithiasis.

  1. Advanced Aerospace Materials by Design

    NASA Technical Reports Server (NTRS)

    Srivastava, Deepak; Djomehri, Jahed; Wei, Chen-Yu

    2004-01-01

    The advances in the emerging field of nanophase thermal and structural composite materials; materials with embedded sensors and actuators for morphing structures; light-weight composite materials for energy and power storage; and large surface area materials for in-situ resource generation and waste recycling, are expected to :revolutionize the capabilities of virtually every system comprising of future robotic and :human moon and mars exploration missions. A high-performance multiscale simulation platform, including the computational capabilities and resources of Columbia - the new supercomputer, is being developed to discover, validate, and prototype next generation (of such advanced materials. This exhibit will describe the porting and scaling of multiscale 'physics based core computer simulation codes for discovering and designing carbon nanotube-polymer composite materials for light-weight load bearing structural and 'thermal protection applications.

  2. Intermediate/Advanced Research Design and Statistics

    NASA Technical Reports Server (NTRS)

    Ploutz-Snyder, Robert

    2009-01-01

    The purpose of this module is To provide Institutional Researchers (IRs) with an understanding of the principles of advanced research design and the intermediate/advanced statistical procedures consistent with such designs

  3. Laser-Induced Fluorescence and Synthetic Jet Fuel Analysis in the Ultra Compact Combustor

    DTIC Science & Technology

    2009-12-01

    flame temperatures, emissions and other characteristics. 6 II. Theory and Previous Research II.1 Standard Gas Turbine Engine Combustor A...losses occur in standard combustors resulting in decreased efficiencies and increased emissions . Combustors create heat and entropy (S) in the...and lowering of the amount of harmful emissions produced. Conventional combustor designs are limited by the fact that combustion reactions require

  4. Combustor and combustor screech mitigation methods

    DOEpatents

    Kim, Kwanwoo; Johnson, Thomas Edward; Uhm, Jong Ho; Kraemer, Gilbert Otto

    2014-05-27

    The present application provides for a combustor for use with a gas turbine engine. The combustor may include a cap member and a number of fuel nozzles extending through the cap member. One or more of the fuel nozzles may be provided in a non-flush position with respect to the cap member.

  5. Slagging retrofit pulsed coal combustor: Final report

    SciTech Connect

    Not Available

    1987-01-01

    A concept for a novel form of slagging retrofit pulsed coal combustor was tested in the laboratory. The combustor is based on controlled use of a form of high pressure amplitude combustion instability. The approach adopted was to resolve, in single pulse experiments, the basic technical issues arising in the development of the combustor. In a cold flow device, the issues of coal spatial distribution were addressed and a combustor and solids disperser configuration was developed to give uniform coal distribution in the combustor. Single pulse ignition experiments were conducted to determine the pressure rise in combustor, pressure rise-decay times, and coal conversion a function of various operating variables. Coal injection, flame propagation, and blowdown times leading to potential combustor size reduction of three times over steady flow combustors were demonstrated. The results give high pressure exhaust leading to potentially improved downstream heat transfer and reduced boiler size. Finally, zero-, one-, and two-dimensional mathematical models were developed in support of the experiments and also to provide design capability. 11 refs., 43 figs.

  6. Metal wastage design guidelines for bubbling fluidized-bed combustors. Final report

    SciTech Connect

    Lyczkowski, R.W.; Podolski, W.F.; Bouillard, J.X.; Folga, S.M.

    1992-11-01

    These metal wastage design guidelines identify relationships between metal wastage and (1) design parameters (such as tube size, tube spacing and pitch, tube bundle and fluidized-bed height to distributor, and heat exchanger tube material properties) and (2) operating parameters (such as fluidizing velocity, particle size, particle hardness, and angularity). The guidelines are of both a quantitative and qualitative nature. Simplified mechanistic models are described, which account for the essential hydrodynamics and metal wastage processes occurring in bubbling fluidized beds. The empirical correlational approach complements the use of these models in the development of these design guidelines. Data used for model and guideline validation are summarized and referenced. Sample calculations and recommended design procedures are included. The influences of dependent variables on metal wastage, such as solids velocity, bubble size, and in-bed pressure fluctuations, are discussed.

  7. Analytical evaluation of the impact of broad specification fuels on high bypass turbofan engine combustors

    NASA Technical Reports Server (NTRS)

    Taylor, J. R.

    1979-01-01

    Six conceptual combustor designs for the CF6-50 high bypass turbofan engine and six conceptual combustor designs for the NASA/GE E3 high bypass turbofan engine were analyzed to provide an assessment of the major problems anticipated in using broad specification fuels in these aircraft engine combustion systems. Each of the conceptual combustor designs, which are representative of both state-of-the-art and advanced state-of-the-art combustion systems, was analyzed to estimate combustor performance, durability, and pollutant emissions when using commercial Jet A aviation fuel and when using experimental referee board specification fuel. Results indicate that lean burning, low emissions double annular combustor concepts can accommodate a wide range of fuel properties without a serious deterioration of performance or durability. However, rich burning, single annular concepts would be less tolerant to a relaxation of fuel properties. As the fuel specifications are relaxed, autoignition delay time becomes much smaller which presents a serious design and development problem for premixing-prevaporizing combustion system concepts.

  8. Design, construction and testing of annular diffusers for high speed civil transportation combustor applications

    NASA Technical Reports Server (NTRS)

    Okhio, Cyril B.

    1995-01-01

    A theoretical and an experimental design study of subsonic flow through curved-wall annular diffusers is being carried out in order to establish the most pertinent design parameters for such devices and the implications of their application in the design of engine components in the aerospace industries. This investigation consists of solving numerically the full Navier Stokes and Continuity equations for the time-mean flow. Various models of turbulence are being evaluated for adoption throughout the study and comparisons would be made with experimental data where they exist. Assessment of diffuser performance based on the dissipated mechanical energy would also be made. The experimental work involves the application of Computer Aided Design software tool to the development of a suitable annular diffuser geometry and the subsequent downloading of such data to a CNC machine at Central State University. The results of the investigations are expected to indicate that more cost effective component design of such devices as effective component design of such devices as diffusers which normally contain complex flows can still be achieved. In this regard a review paper was accepted and presented at the First International Conference on High Speed Civil Transportation Research held at North Carolina A&T in December of 1994.

  9. Compliant Metal Enhanced Convection Cooled Reverse-Flow Annular Combustor

    NASA Technical Reports Server (NTRS)

    Paskin, Marc D.; Acosta, Waldo A.

    1994-01-01

    A joint Army/NASA program was conducted to design, fabricate, and test an advanced, reverse-flow, small gas turbine combustor using a compliant metal enhanced (CME) convection wall cooling concept. The objectives of this effort were to develop a design method (basic design data base and analysis) for the CME cooling technique and tben demonstrate its application to an advanced cycle, small, reverse-flow combustor with 3000 F (1922 K) burner outlet temperature (BOT). The CME concept offers significant improvements in wall cooling effectiveness resulting in a large reduction in cooling air requirements. Therefore, more air is available for control of burner outlet temperature pattern in addition to the benefit of improved efficiency, reduced emissions, and smoke levels. Rig test results demonstrated the benefits and viability of the CME concept meeting or exceeding the aerothermal performance and liner wall temperature characteristics of similar lower temperature-rise combustors, achieving 0.15 pattern factor at 3000 F (1922 K) BOT, while utilizing approximately 80 percent less cooling air than conventional, film-cooled combustion systems.

  10. Multi-port dump combustor

    SciTech Connect

    Dale, L. A.; Grenleski Jr., S. E.; Keirsey, J. L.; Stevens, C. E.

    1985-09-10

    A four-ported dump combustor is designed for use with a ramjet engine and provides high combustion efficiency and pressure recovery for length-to-diameter (L/D) ratios of between 1.3 and 4.4, over a range of operating conditions.

  11. Premixed Prevaporized Combustor Technology Forum

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The Forum was held to present the results of recent and current work intended to provide basic information required for demonstration of lean, premixed prevaporized combustors for aircraft gas turbine engine application. Papers are presented which deal with the following major topics: (1) engine interfaces; (2) fuel-air preparation; (3) autoignition; (4) lean combustion; and (5) concept design studies.

  12. Design, Construction and Testing of Annular Diffusers for High Speed Civil Transportation Combustor Applications

    NASA Technical Reports Server (NTRS)

    Okhio, Cyril B.

    1996-01-01

    A theoretical and an experimental design study of subsonic flow through curved-wall annular diffusers has been initiated under this award in order to establish the most pertinent design parameters and hence performance characteristics for such devices, an the implications of their application in the design of engine components in the aerospace industries. The diffusers under this study are expected to contain appreciable regions of stall and the effects of swirl on their performance are being studied. The experimental work involves the application of Computer Aided Design software tool to the development of a suitable annular diffuse geometry and the subsequent downloading of such data to a CNC machine at Central State University (CSU). Two experimental run segments have been completed so far during FY-95 involving flow visualization and diffuser performance evaluation based on Kinetic Energy Dissipation. The method of calculation of the performance of diffusers based on pressure recovery coefficient has been shown to have some shortcomings and so the kinetic energy dissipation approach has been introduced in the run segment two with some success. The application of the discretized, full Navier Stokes and Continuity equations to the numerical study of the problem described above for the time-mean flow is expected to follow. Various models of turbulence are being evaluated for adoption throughout the study and comparisons would be made with experimental data where they exist. Assessment of diffuser performance based on the dissipated mechanical energy would also be made. The result of the investigations are expected to indicate that more cost effective component design of such devices as diffusers which normally contain complex flows can still be achieved.

  13. Design considerations and operating experience in firing refuse derived fuel in a circulating fluidized bed combustor

    SciTech Connect

    Piekos, S.J.; Matuny, M.

    1997-12-31

    The worldwide demand for cleaner, more efficient methods to dispose of municipal solid waste has stimulated interest in processing solid waste to produce refuse derived fuel (RDF) for use in circulating fluidized bed (CFB) boilers. The combination of waste processing and materials recovery systems and CFB boiler technology provides the greatest recovery of useful resources from trash and uses the cleanest combustion technology available today to generate power. Foster Wheeler Power Systems along with Foster Wheeler Energy Corporation and several other Foster Wheeler sister companies designed, built, and now operates a 1600 tons per day (TPD) (1450 metric tons) municipal waste-to-energy project located in Robbins, Illinois, a suburb of Chicago. This project incorporates waste processing systems to recover recyclable materials and produce RDF. It is the first project in the United States to use CFB boiler technology to combust RDF. This paper will provide an overview of the Robbins, Illinois waste-to-energy project and will examine the technical and environmental reasons for selecting RDF waste processing and CFB combustion technology. Additionally, this paper will present experience with handling and combusting RDF and review the special design features incorporated into the CFB boiler and waste processing system that make it work.

  14. Pollutant emissions from and within a model gas turbine combustor at elevated pressures and temperatures

    NASA Technical Reports Server (NTRS)

    Drennan, S. A.; Peterson, C. O.; Khatib, F. M.; Sowa, W. A.; Samuelsen, G. S.

    1993-01-01

    Conventional and advanced gas turbine engines are coming under increased scrutiny regarding pollutant emissions. This, in turn, has created a need to obtain in-situ experimental data at practical conditions, as well as exhaust data, and to obtain the data in combustors that reflect modern designs. The in-situ data are needed to (1) assess the effects of design modifications on pollutant formation, and (2) develop a detailed data base on combustor performance for the development and verification of computer modeling. This paper reports on a novel high pressure, high temperature facility designed to acquire such data under controlled conditions and with access (optical and extractive) for in-situ measurements. To evaluate the utility of the facility, a model gas turbine combustor was selected which features practical hardware design, two rows of jets (primary and dilution) with four jets in each row, and advanced wall cooling techniques with laser drilled effusive holes. The dome is equipped with a flat-vaned swirler with vane angles of 60 degrees. Data are obtained at combustor pressures ranging from 2 to 10 atmospheres of pressure, levels of air preheat to 427 C, combustor reference velocities from 10.0 to 20.0 m/s, and an overall equivalence ratio of 0.3. Exit plane and in-situ measurements are presented for HC, O2, CO2, CO, and NO(x). The exit plane emissions of NO(x) correspond to levels reported from practical combustors and the in-situ data demonstrate the utility and potential for detailed flow field measurements.

  15. Low NOx Heavy Fuel Combustor Concept Program

    NASA Technical Reports Server (NTRS)

    Novick, A. S.; Troth, D. L.

    1981-01-01

    The development of the technology required to operate an industrial gas turbine combustion system on minimally processed, heavy petroleum or residual fuels having high levels of fuel-bound nitrogen (FBN) while producing acceptable levels of exhaust emissions is discussed. Three combustor concepts were designed and fabricated. Three fuels were supplied for the combustor test demonstrations: a typical middle distillate fuel, a heavy residual fuel, and a synthetic coal-derived fuel. The primary concept was an air staged, variable-geometry combustor designed to produce low emissions from fuels having high levels of FBN. This combustor used a long residence time, fuel-rich primary combustion zone followed by a quick-quench air mixer to rapidly dilute the fuel rich products for the fuel-lean final burnout of the fuel. This combustor, called the rich quench lean (RQL) combustor, was extensively tested using each fuel over the entire power range of the model 570 K engine. Also, a series of parameteric tests was conducted to determine the combustor's sensitivity to rich-zone equivalence ratio, lean-zone equivalence ratio, rich-zone residence time, and overall system pressure drop. Minimum nitrogen oxide emissions were measured at 50 to 55 ppmv at maximum continuous power for all three fuels. Smoke was less than a 10 SAE smoke number.

  16. Emission characteristics of a liquid spray sudden expansion combustor using computational fluid dynamics

    NASA Astrophysics Data System (ADS)

    Rodriguez, Daniel

    A sudden expansion combustor (SUE) is analyzed using computation fluid dynamics (CFD). CO emissions and NOx emissions are computed for various operating conditions of the SUE combustor using a can type and an annular type geometrical configurations. The goal of this thesis is to see if the SUE combustor is a viable alternative to conventional combustors which utilize swirlers. It is found that for the can type combustor the NO x emissions were quite low compared to other combustor types but the CO emissions were fairly high. The annular combustor shows better CO emissions compared to the can type, but the CO emissions are still high compared to other combustors. Emissions can be improved by providing better mixing in the primary combustion zone. The SUE combustor design needs to be further refined in order for it to be a viable alternative to conventional combustors with swirlers.

  17. PULSE COMBUSTOR DESIGN QUALIFICATION TEST AND CLEAN COAL FEEDSTOCK TEST - VOLUME I AND VOLUME II

    SciTech Connect

    Unknown

    2002-02-08

    For this Cooperative Agreement, the pulse heater module is the technology envelope for an indirectly heated steam reformer. The field of use of the steam reformer pursuant to this Cooperative Agreement with DOE is for the processing of sub-bituminous coals and lignite. The main focus is the mild gasification of such coals for the generation of both fuel gas and char--for the steel industry is the main focus. An alternate market application for the substitution of metallurgical coke is also presented. This project was devoted to qualification of a 253-tube pulse heater module. This module was designed, fabricated, installed, instrumented and tested in a fluidized bed test facility. Several test campaigns were conducted. This larger heater is a 3.5 times scale-up of the previous pulse heaters that had 72 tubes each. The smaller heater has been part of previous pilot field testing of the steam reformer at New Bern, North Carolina. The project also included collection and reduction of mild gasification process data from operation of the process development unit (PDU). The operation of the PDU was aimed at conditions required to produce char (and gas) for the Northshore Steel Operations. Northshore Steel supplied the coal for the process unit tests.

  18. A review of NASA combustor and turbine heat transfer research

    NASA Technical Reports Server (NTRS)

    Rudey, R. A.; Graham, R. W.

    1984-01-01

    The thermal design of the combustor and turbine of a gas turbine engine poses a number of difficult heat transfer problems. The importance of improved prediction techniques becomes more critical in anticipation of future generations of gas turbine engines which will operate at higher cycle pressure and temperatures. Research which addresses many of the complex heat transfer processes holds promise for yielding significant improvements in prediction of metal temperatures. Such research involves several kinds of program including: (1) basic experiments which delineate the fundamental flow and heat transfer phenomena that occur in the hot sections of the gas turbine but at low enthalpy conditions; (2) analytical modeling of these flow and heat transfer phenomena which results from the physical insights gained in experimental research; and (3) verification of advanced prediction techniques in facilities which operate near the real engine thermodynamic conditions. In this paper, key elements of the NASA program which involves turbine and combustor heat transfer research will be described and discussed.

  19. Rapid mix concepts for low emission combustors in gas turbine engines

    NASA Technical Reports Server (NTRS)

    Talpallikar, Milind V.; Smith, Clifford E.; Lai, Ming-Chia

    1990-01-01

    NASA LeRC has identified the Rich burn/Quick mix/Lean burn (RQL) combustor as a potential gas turbine combustor concept to reduce NOx emissions in High Speed Civil Transport (HSCT) aircraft. To demonstrate reduced NOx levels, NASA LeRC soon will test a flametube version of an RQL combustor. The critical technology needed for the RQL combustor is a method of quickly mixing combustion air with rich burn gases. Two concepts were proposed to enhance jet mixing in a circular cross-section: the Asymmetric Jet Penetration (AJP) concept; and the Lobed Mixer (LM) concept. In Phase 1, two preliminary configurations of the AJP concept were compared with a conventional 12-jet radial-inflow slot design. The configurations were screened using an advanced 3-D Computational Fluid Dynamics (CFD) code named REFLEQS. Both non-reacting and reacting analyses were performed. For an objective comparison, the conventional design was optimized by parametric variation of the jet-to-mainstream momentum flux (J) ratio. The optimum J was then employed in the AJP simulations. Results showed that the three-jet AJP configuration was superior in overall mixedness compared to the conventional design. However, in regards to NOx emissions, the AJP configuration was inferior. The higher emission level for AJP was caused by a single hot spot located in the wake of the central jet as it entered the combustor. Ways of maintaining good mixedness while eliminating the hot spot were identified for Phase 2 study. Overall, Phase 1 showed the viability of using CFD analyses to evaluate quick-mix concepts. A high probability exists that advancing mixing concepts will reduce NOx emissions in RQL combustors, and should be explored in Phase 2, by parallel numerical and experimental work.

  20. Modeling Tool Advances Rotorcraft Design

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Continuum Dynamics Inc. (CDI), founded in 1979, specializes in advanced engineering services, including fluid dynamic modeling and analysis for aeronautics research. The company has completed a number of SBIR research projects with NASA, including early rotorcraft work done through Langley Research Center, but more recently, out of Ames Research Center. NASA Small Business Innovation Research (SBIR) grants on helicopter wake modeling resulted in the Comprehensive Hierarchical Aeromechanics Rotorcraft Model (CHARM), a tool for studying helicopter and tiltrotor unsteady free wake modeling, including distributed and integrated loads, and performance prediction. Application of the software code in a blade redesign program for Carson Helicopters, of Perkasie, Pennsylvania, increased the payload and cruise speeds of its S-61 helicopter. Follow-on development resulted in a $24 million revenue increase for Sikorsky Aircraft Corporation, of Stratford, Connecticut, as part of the company's rotor design efforts. Now under continuous development for more than 25 years, CHARM models the complete aerodynamics and dynamics of rotorcraft in general flight conditions. CHARM has been used to model a broad spectrum of rotorcraft attributes, including performance, blade loading, blade-vortex interaction noise, air flow fields, and hub loads. The highly accurate software is currently in use by all major rotorcraft manufacturers, NASA, the U.S. Army, and the U.S. Navy.

  1. Fuel cell system combustor

    DOEpatents

    Pettit, William Henry

    2001-01-01

    A fuel cell system including a fuel reformer heated by a catalytic combustor fired by anode and cathode effluents. The combustor includes a turbulator section at its input end for intimately mixing the anode and cathode effluents before they contact the combustors primary catalyst bed. The turbulator comprises at least one porous bed of mixing media that provides a tortuous path therethrough for creating turbulent flow and intimate mixing of the anode and cathode effluents therein.

  2. Introducing the VRT gas turbine combustor

    NASA Technical Reports Server (NTRS)

    Melconian, Jerry O.; Mostafa, Abdu A.; Nguyen, Hung Lee

    1990-01-01

    An innovative annular combustor configuration is being developed for aircraft and other gas turbine engines. This design has the potential of permitting higher turbine inlet temperatures by reducing the pattern factor and providing a major reduction in NO(x) emission. The design concept is based on a Variable Residence Time (VRT) technique which allows large fuel particles adequate time to completely burn in the circumferentially mixed primary zone. High durability of the combustor is achieved by dual function use of the incoming air. The feasibility of the concept was demonstrated by water analogue tests and 3-D computer modeling. The computer model predicted a 50 percent reduction in pattern factor when compared to a state of the art conventional combustor. The VRT combustor uses only half the number of fuel nozzles of the conventional configuration. The results of the chemical kinetics model require further investigation, as the NO(x) predictions did not correlate with the available experimental and analytical data base.

  3. Gas turbine combustor transition

    DOEpatents

    Coslow, Billy Joe; Whidden, Graydon Lane

    1999-01-01

    A method of converting a steam cooled transition to an air cooled transition in a gas turbine having a compressor in fluid communication with a combustor, a turbine section in fluid communication with the combustor, the transition disposed in a combustor shell and having a cooling circuit connecting a steam outlet and a steam inlet and wherein hot gas flows from the combustor through the transition and to the turbine section, includes forming an air outlet in the transition in fluid communication with the cooling circuit and providing for an air inlet in the transition in fluid communication with the cooling circuit.

  4. Gas turbine combustor transition

    DOEpatents

    Coslow, B.J.; Whidden, G.L.

    1999-05-25

    A method is described for converting a steam cooled transition to an air cooled transition in a gas turbine having a compressor in fluid communication with a combustor, a turbine section in fluid communication with the combustor, the transition disposed in a combustor shell and having a cooling circuit connecting a steam outlet and a steam inlet and wherein hot gas flows from the combustor through the transition and to the turbine section, includes forming an air outlet in the transition in fluid communication with the cooling circuit and providing for an air inlet in the transition in fluid communication with the cooling circuit. 7 figs.

  5. Advanced Turbine System (ATS) program conceptual design and product development. Quarterly report, March 1--May 31, 1995

    SciTech Connect

    1995-12-31

    Achieving the goals of 60% efficiency, 8 ppmvd NOx, and 10% electric power cost reduction imposes competing characteristics on the gas turbine system: the turbine inlet temperature of the gas turbine must increase, leading also to increased NOx emission. However, improved coating and materials technologies along with creative combustor design can result in solutions to achieve the ultimate goal. The program is focused on two specific products: a 70MW class industrial gas turbine based on the GE90 core technology utilizing an innovative air cooling technology, and a 200MW class utility gas turbine based on an advanced GE heavy duty machine utilizing advanced cooling and enhancement in component efficiency.

  6. Alternate-Fueled Combustor-Sector Performance. Parts A and B; (A) Combustor Performance; (B) Combustor Emissions

    NASA Technical Reports Server (NTRS)

    Shouse, D. T.; Hendricks, R. C.; Lynch, A.; Frayne, C. W.; Stutrud, J. S.; Corporan, E.; Hankins, T.

    2012-01-01

    Alternate aviation fuels for military or commercial use are required to satisfy MIL-DTL-83133F(2008) or ASTM D 7566 (2010) standards, respectively, and are classified as "drop-in" fuel replacements. To satisfy legacy issues, blends to 50% alternate fuel with petroleum fuels are certified individually on the basis of processing and assumed to be feedstock agnostic. Adherence to alternate fuels and fuel blends requires "smart fueling systems" or advanced fuel-flexible systems, including combustors and engines, without significant sacrifice in performance or emissions requirements. This paper provides preliminary performance (Part A) and emissions and particulates (Part B) combustor sector data. The data are for nominal inlet conditions at 225 psia and 800 F (1.551 MPa and 700 K), for synthetic-paraffinic-kerosene- (SPK-) type (Fisher-Tropsch (FT)) fuel and blends with JP-8+100 relative to JP-8+100 as baseline fueling. Assessments are made of the change in combustor efficiency, wall temperatures, emissions, and luminosity with SPK of 0%, 50%, and 100% fueling composition at 3% combustor pressure drop. The performance results (Part A) indicate no quantifiable differences in combustor efficiency, a general trend to lower liner and higher core flow temperatures with increased FT fuel blends. In general, emissions data (Part B) show little differences, but with percent increase in FT-SPK-type fueling, particulate emissions and wall temperatures are less than with baseline JP-8. High-speed photography illustrates both luminosity and combustor dynamic flame characteristics.

  7. Hypermixer Pylon Fuel Injection for Scramjet Combustors

    DTIC Science & Technology

    2008-09-11

    wall cavities, intrusive geometries like pylons and struts , or a combination thereof. The type of fuel injection strategy largely depends on the...be affixed to combustor walls or placed on intru- sive geometries like struts or pylons. Wall injection comes with an inherent combustor airflow...only one wall . Using in-stream struts and pylons as fueling devices has been a common practice in scramjet design. Much research continues to be

  8. High Frequency Adaptive Instability Suppression Controls in a Liquid-Fueled Combustor

    NASA Technical Reports Server (NTRS)

    Kopasakis, George

    2003-01-01

    This effort extends into high frequency (>500 Hz), an earlier developed adaptive control algorithm for the suppression of thermo-acoustic instabilities in a liquidfueled combustor. The earlier work covered the development of a controls algorithm for the suppression of a low frequency (280 Hz) combustion instability based on simulations, with no hardware testing involved. The work described here includes changes to the simulation and controller design necessary to control the high frequency instability, augmentations to the control algorithm to improve its performance, and finally hardware testing and results with an experimental combustor rig developed for the high frequency case. The Adaptive Sliding Phasor Averaged Control (ASPAC) algorithm modulates the fuel flow in the combustor with a control phase that continuously slides back and forth within the phase region that reduces the amplitude of the instability. The results demonstrate the power of the method - that it can identify and suppress the instability even when the instability amplitude is buried in the noise of the combustor pressure. The successful testing of the ASPAC approach helped complete an important NASA milestone to demonstrate advanced technologies for low-emission combustors.

  9. Alternate-Fueled Combustor-Sector Performance: Part A: Combustor Performance Part B: Combustor Emissions

    NASA Technical Reports Server (NTRS)

    Shouse, D. T.; Neuroth, C.; Henricks, R. C.; Lynch, A.; Frayne, C.; Stutrud, J. S.; Corporan, E.; Hankins, T.

    2010-01-01

    Alternate aviation fuels for military or commercial use are required to satisfy MIL-DTL-83133F(2008) or ASTM D 7566 (2010) standards, respectively, and are classified as drop-in fuel replacements. To satisfy legacy issues, blends to 50% alternate fuel with petroleum fuels are certified individually on the basis of feedstock. Adherence to alternate fuels and fuel blends requires smart fueling systems or advanced fuel-flexible systems, including combustors and engines without significant sacrifice in performance or emissions requirements. This paper provides preliminary performance (Part A) and emissions and particulates (Part B) combustor sector data for synthetic-parafinic-kerosene- (SPK-) type fuel and blends with JP-8+100 relative to JP-8+100 as baseline fueling.

  10. Combustor Modelling

    DTIC Science & Technology

    1980-02-01

    three-dimensional gas turbine combustion chamber flows. ASME 23rd Int. Gas Turbine Conference. London (1978) 10). R.S. Reynolds, T.E. Kuhn & H.C. Mongia ... combustion data. 2 4 The concept of this global model approach is to trantform the TJI region in a physically compatible way that can be computationally...is also addressed.- ee a ot s um FUEL EFFECTS ON GAS TURBINE COMBUSTION : Fuel characteristics which are most likely to, affect the design- of future

  11. Experimental clean combustor program: Noise study

    NASA Technical Reports Server (NTRS)

    Sofrin, T. G.; Riloff, N., Jr.

    1976-01-01

    Under a Noise Addendum to the NASA Experimental Clean Combustor Program (ECCP) internal pressure fluctuations were measured during tests of JT9D combustor designs conducted in a burner test rig. Measurements were correlated with burner operating parameters using an expression relating farfield noise to these parameters. For a given combustor, variation of internal noise with operating parameters was reasonably well predicted by this expression but the levels were higher than farfield predictions and differed significantly among several combustors. For two burners, discharge stream temperature fluctuations were obtained with fast-response thermocouples to allow calculation of indirect combustion noise which would be generated by passage of the temperature inhomogeneities through the high pressure turbine stages of a JT9D turbofan engine. Using a previously developed analysis, the computed indirect combustion noise was significantly lower than total low frequency core noise observed on this and several other engines.

  12. Application of Gas Analysis to Combustor Research

    NASA Technical Reports Server (NTRS)

    Hibbard, R. R.; Evans, Albert

    1959-01-01

    The performance of turbine-engine combustors usually is given in terms of operating limits and combustion efficiency. The latter property is determined most often by measuring the increase in enthalpy across the combustor through the use of thermocouples. This investigation was conducted to determine the ability of gas-analytical techniques to provide additional information about combustor performance. Gas samples were taken at the outlet and two upstream stations and their compositions determined. In addition to over-all combustion efficiency, estimates of local fuel-air ratios, local combustion efficiencies, and heat-release rates can be made. Conclusions can be drawn concerning the causes of combustion inefficiency and may permit corrective design changes to be made more intelligently. The purpose of this investigation was not to present data for a given combustor but rather to show the types and value of additional information that can be gained from gas-analytical data.

  13. Modular combustor dome

    NASA Technical Reports Server (NTRS)

    Glynn, Christopher Charles (Inventor); Halila, Ely Eskenazi (Inventor); Bibler, John David (Inventor); Morris, David Byron (Inventor)

    2001-01-01

    A combustor dome module includes a mixer tube having a hollow heat shield sealingly joined around the outlet end thereof. The modules may then be assembled in an array for defining the combustor dome, with each module being individually removable therefrom.

  14. Variable volume combustor

    DOEpatents

    Ostebee, Heath Michael; Ziminsky, Willy Steve; Johnson, Thomas Edward; Keener, Christopher Paul

    2017-01-17

    The present application provides a variable volume combustor for use with a gas turbine engine. The variable volume combustor may include a liner, a number of micro-mixer fuel nozzles positioned within the liner, and a linear actuator so as to maneuver the micro-mixer fuel nozzles axially along the liner.

  15. Advanced transport design using multidisciplinary design optimization

    NASA Technical Reports Server (NTRS)

    Barnum, Jennifer; Bathras, Curt; Beene, Kirk; Bush, Michael; Kaupin, Glenn; Lowe, Steve; Sobieski, Ian; Tingen, Kelly; Wells, Douglas

    1991-01-01

    This paper describes the results of the first implementation of multidisciplinary design optimisation (MDO) techniques by undergraduates ina design course. The objective of the work was to design a civilian transport aircraft of the Boeing 777 class. The first half of the two semester design course consisted of application of traditional sizing methods and techniques to form a baseline aircraft. MDO techniques were then applied to this baseline design. This paper describes the evolution of the design with special emphasis on the application of MDO techniques, and presents the results of four iterations through the design space. Minimization of take-off gross weight was the goal of the optimization process. The resultant aircraft derived from the MDO procedure weighed approximately 13,382 lbs (2.57 percent) less than the baseline aircraft.

  16. Gas turbine combustor

    NASA Technical Reports Server (NTRS)

    Burd, Steven W. (Inventor); Cheung, Albert K. (Inventor); Dempsey, Dae K. (Inventor); Hoke, James B. (Inventor); Kramer, Stephen K. (Inventor); Ols, John T. (Inventor); Smith, Reid Dyer Curtis (Inventor); Sowa, William A. (Inventor)

    2011-01-01

    A gas turbine engine has a combustor module including an annular combustor having a liner assembly that defines an annular combustion chamber having a length, L. The liner assembly includes a radially inner liner, a radially outer liner that circumscribes the inner liner, and a bulkhead, having a height, H1, which extends between the respective forward ends of the inner liner and the outer liner. The combustor has an exit height, H3, at the respective aft ends of the inner liner and the outer liner interior. The annular combustor has a ratio H1/H3 having a value less than or equal to 1.7. The annular combustor may also have a ration L/H3 having a value less than or equal to 6.0.

  17. Advanced Overfire Air system and design

    SciTech Connect

    Gene berkau

    2004-07-30

    The objective of the proposed project is to design, install and optimize a prototype advanced tangential OFA air system on two mass feed stoker boilers that can burn coal, biomass and a mixture of these fuels. The results will be used to develop a generalized methodology for retrofit designs and optimization of advanced OFA air systems. The advanced OFA system will reduce particulate and NOx emissions and improve overall efficiency by reducing carbon in the ash and excess oxygen. The advanced OFA will also provide capabilities for carrying full load and improved load following and transitional operations.

  18. Operational procedure for computer program for design point characteristics of a compressed-air generator with through-flow combustor for V/STOL applications

    NASA Technical Reports Server (NTRS)

    Krebs, R. P.

    1971-01-01

    The computer program described in this report calculates the design-point characteristics of a compressed-air generator for use in V/STOL applications such as systems with a tip-turbine-driven lift fan. The program computes the dimensions and mass, as well as the thermodynamic performance of a model air generator configuration which involves a straight through-flow combustor. Physical and thermodynamic characteristics of the air generator components are also given. The program was written in FORTRAN IV language. Provision has been made so that the program will accept input values in either SI units or U.S. customary units. Each air generator design-point calculation requires about 1.5 seconds of 7094 computer time for execution.

  19. Linear test bed. Volume 1: Test bed no. 1. [aerospike test bed with segmented combustor

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The Linear Test Bed program was to design, fabricate, and evaluation test an advanced aerospike test bed which employed the segmented combustor concept. The system is designated as a linear aerospike system and consists of a thrust chamber assembly, a power package, and a thrust frame. It was designed as an experimental system to demonstrate the feasibility of the linear aerospike-segmented combustor concept. The overall dimensions are 120 inches long by 120 inches wide by 96 inches in height. The propellants are liquid oxygen/liquid hydrogen. The system was designed to operate at 1200-psia chamber pressure, at a mixture ratio of 5.5. At the design conditions, the sea level thrust is 200,000 pounds. The complete program including concept selection, design, fabrication, component test, system test, supporting analysis and posttest hardware inspection is described.

  20. Advanced Beamline Design for Fermilab's Advanced Superconducting Test Accelerator

    SciTech Connect

    Prokop, Christopher

    2014-01-01

    The Advanced Superconducting Test Accelerator (ASTA) at Fermilab is a new electron accelerator currently in the commissioning stage. In addition to testing superconducting accelerating cavities for future accelerators, it is foreseen to support a variety of Advanced Accelerator R&D (AARD) experiments. Producing the required electron bunches with the expected flexibility is challenging. The goal of this dissertation is to explore via numerical simulations new accelerator beamlines that can enable the advanced manipulation of electron bunches. The work especially includes the design of a low-energy bunch compressor and a study of transverse-to-longitudinal phase space exchangers.

  1. Effects of Combustion-Induced Vortex Breakdown on Flashback Limits of Syngas-Fueled Gas Turbine Combustors

    SciTech Connect

    Ahsan Choudhuri

    2011-03-31

    Turbine combustors of advanced power systems have goals to achieve very low pollutants emissions, fuel variability, and fuel flexibility. Future generation gas turbine combustors should tolerate fuel compositions ranging from natural gas to a broad range of syngas without sacrificing operational advantages and low emission characteristics. Additionally, current designs of advanced turbine combustors use various degrees of swirl and lean premixing for stabilizing flames and controlling high temperature NOx formation zones. However, issues of fuel variability and NOx control through premixing also bring a number of concerns, especially combustor flashback and flame blowout. Flashback is a combustion condition at which the flame propagates upstream against the gas stream into the burner tube. Flashback is a critical issue for premixed combustor designs, because it not only causes serious hardware damages but also increases pollutant emissions. In swirl stabilized lean premixed turbine combustors onset of flashback may occur due to (i) boundary layer flame propagation (critical velocity gradient), (ii) turbulent flame propagation in core flow, (iii) combustion instabilities, and (iv) upstream flame propagation induced by combustion induced vortex breakdown (CIVB). Flashback due to first two foregoing mechanisms is a topic of classical interest and has been studied extensively. Generally, analytical theories and experimental determinations of laminar and turbulent burning velocities model these mechanisms with sufficient precision for design usages. However, the swirling flow complicates the flashback processes in premixed combustions and the first two mechanisms inadequately describe the flashback propensity of most practical combustor designs. The presence of hydrogen in syngas significantly increases the potential for flashback. Due to high laminar burning velocity and low lean flammability limit, hydrogen tends to shift the combustor operating conditions towards

  2. Development of a high-temperature durable catalyst for use in catalytic combustors for advanced automotive gas turbine engines

    NASA Technical Reports Server (NTRS)

    Tong, H.; Snow, G. C.; Chu, E. K.; Chang, R. L. S.; Angwin, M. J.; Pessagno, S. L.

    1981-01-01

    Durable catalytic reactors for advanced gas turbine engines were developed. Objectives were: to evaluate furnace aging as a cost effective catalytic reactor screening test, measure reactor degradation as a function of furnace aging, demonstrate 1,000 hours of combustion durability, and define a catalytic reactor system with a high probability of successful integration into an automotive gas turbine engine. Fourteen different catalytic reactor concepts were evaluated, leading to the selection of one for a durability combustion test with diesel fuel for combustion conditions. Eight additional catalytic reactors were evaluated and one of these was successfully combustion tested on propane fuel. This durability reactor used graded cell honeycombs and a combination of noble metal and metal oxide catalysts. The reactor was catalytically active and structurally sound at the end of the durability test.

  3. High-Temperature-Turbine Technology Program: Phase II. Technology test and support studies. Design and development of the liquid-fueled high-temperature combustor for the Turbine Spool Technology Rig

    SciTech Connect

    1981-06-01

    The concept selected by Curtiss-Wright for this DOE sponsored High Temperature Turbine Technology (HTTT) Program utilizes transpiration air-cooling of the turbine subsystem airfoils. With moderate quantities of cooling air, this method of cooling has been demonstrated to be effective in a 2600 to 3000/sup 0/F gas stream. Test results show that transpiration air-cooling also protects turbine components from the aggressive environment produced by the combustion of coal-derived fuels. A new single-stage, high work transpiration air-cooled turbine has been designed and fabricated for evaluation in a rotating test vehicle designated the Turbine Spool Technology Rig (TSTR). The design and development of the annular combustor for the TSTR are described. Some pertinent design characteristics of the combustor are: fuel, Jet A; inlet temperature, 525/sup 0/F; inlet pressure, 7.5 Atm; temperature rise, 2475/sup 0/F; efficiency, 98.5%; exit temperature pattern, 0.25; and exit mass flow, 92.7 pps. The development program was conducted on a 60/sup 0/ sector of the full-round annular combustor. Most design goals were achieved, with the exception of the peak gas exit temperature and local metal temperatures at the rear of the inner liner, both of which were higher than the design values. Subsequent turbine vane cascade testing established the need to reduce both the peak gas temperature (for optimum vane cooling) and the inner liner metal temperature (for combustor durability). Further development of the 60/sup 0/ combustor sector achieved the required temperature reductions and the final configuration was incorporated in the TSTR full-annular burner.

  4. Development of a high-temperature durable catalyst for use in catalytic combustors for advanced automotive gas turbine engines

    SciTech Connect

    Tong, H; Snow, G C; Chu, E K :; Chang, R L.S.; Angwin, M J; Pessagno, S L

    1981-09-01

    An experimental program was performed to develop durable catalytic reactors for advanced gas turbine engines. This program was performed as part of DOE's Gas Turbine Highway Vehicle Systems Project. Objectives of this program were to evaluate furnace aging as a cost-effective catalytic reactor screening test, measure reactor degradation as a function of furnace aging, demonstrate 1000 h of combustion durability, and define a catalytic reactor system with a high probability of successfful integration into an automotive gas turbine engine. In the first phase of this program, 14 different catalytic reactor concepts were evaluated, leading to the selection of one for a durability combustion test with diesel fuel at 1700 K combustion coditions. The durability reactor, a proprietary UOP noble metal catalyst, failed structurally after about 136 h and the catalyst was essentially inactive after about 226 h. In Phase II, eight additional catalytic reactors were evalated and one of these was sucessfully combustion-tested for 1000 h at 1700 K on propane fuel. This durability reactor used graded-cell honeycombs and a combination of noble metal and metal oxide catalysts. The reactor was catalytically active and structurally sound at the end of the durability test.

  5. Combustor liner cooling system

    DOEpatents

    Lacy, Benjamin Paul; Berkman, Mert Enis

    2013-08-06

    A combustor liner is disclosed. The combustor liner includes an upstream portion, a downstream end portion extending from the upstream portion along a generally longitudinal axis, and a cover layer associated with an inner surface of the downstream end portion. The downstream end portion includes the inner surface and an outer surface, the inner surface defining a plurality of microchannels. The downstream end portion further defines a plurality of passages extending between the inner surface and the outer surface. The plurality of microchannels are fluidly connected to the plurality of passages, and are configured to flow a cooling medium therethrough, cooling the combustor liner.

  6. Dual-Mode Combustor

    NASA Technical Reports Server (NTRS)

    Trefny, Charles J (Inventor); Dippold, Vance F (Inventor)

    2013-01-01

    A new dual-mode ramjet combustor used for operation over a wide flight Mach number range is described. Subsonic combustion mode is usable to lower flight Mach numbers than current dual-mode scramjets. High speed mode is characterized by supersonic combustion in a free-jet that traverses the subsonic combustion chamber to a variable nozzle throat. Although a variable combustor exit aperture is required, the need for fuel staging to accommodate the combustion process is eliminated. Local heating from shock-boundary-layer interactions on combustor walls is also eliminated.

  7. Advanced Design Studies. Final report

    SciTech Connect

    Steiner, Don

    2012-12-01

    The ARIES-CS project was a multi-year multi-institutional project to assess the feasibility of a compact stellarator as a fusion power plant. The work herein describes efforts to help design one aspect of the device, the divertor, which is responsible for the removal of particle and heat flux from the system, acting as the first point of contact between the magnetically confined hot plasma and the outside world. Specifically, its location and topology are explored, extending previous work on the sub ject. An optimized design is determined for the thermal particle flux using a suite of 3D stellarator design codes which trace magnetic field lines from just inside the confined plasma edge to their strike points on divertor plates. These divertor plates are specified with a newly developed plate design code. It is found that a satisfactory thermal design exists which maintains the plate temperature and heat load distribution below tolerable engineering limits. The design is unique, including a toroidal taper on the outboard plates which was found to be important to our results. The maximum thermal heat flux for the final design was 3.61 M W/m2 and the maximum peaking factor was 10.3, below prescribed limits of 10 M W/m2 and 15.6, respectively. The median length of field lines reaching the plates is about 250 m and their average angle of inclination to the surface is 2 deg. Finally, an analysis of the fast alphas, resulting from fusion in the core, which escape the plasma was performed. A method is developed for obtaining the mapping from magnetic coordinates to real-space coordinates for the ARIES-CS. This allows the alpha exit locations to be identified in real space for the first time. These were then traced using the field line algorithm as well as a guiding center routine accounting for their mass, charge, and specific direction and energy. Results show that the current design is inadequate for accommodating the alpha heat flux, capturing at most 1/3 of lost alphas

  8. Advances on ELIC Design Studies

    SciTech Connect

    Bogacz, S. Alex; Bogacz, S.; Chevtsov, P.; Derbenev, Ya.; Evtushenko, P.; Krafft, G.; Hutton, A.; Li, R.; Merminga, L.; Musson, J.; Yunn, B.; Zhang, Y.; Sayed, H.; Qiang, J.

    2008-06-16

    A conceptual design of a ring-ring electron-ion collider based on CEBAF with a center-of-mass energy up to 90 GeV at luminosity up to 1035 cm-2s-1 has been proposed at JLab to fulfil science requirements. Here, we summarize design progress including collider ring and interaction region optics with chromatic aberration compensation. Electron polarization in the Figure-8 ring, stacking of ion beams in an accumulator-cooler ring, beam-beam simulations and a faster kicker for the circulator electron cooler ring are also discussed.

  9. The demonstration of an advanced cyclone coal combustor, with internal sulfur, nitrogen, and ash control for the conversion of a 23 MMBtu/hour oil fired boiler to pulverized coal

    SciTech Connect

    Zauderer, B.; Fleming, E.S.

    1991-08-30

    The project objective was to demonstrate a technology which can be used to retrofit oil/gas designed boilers, and conventional pulverized coal fired boilers to direct coal firing, by using a patented sir cooled coal combustor that is attached in place of oil/gas/coal burners. A significant part of the test effort was devoted to resolving operational issues related to uniform coal feeding, efficient combustion under very fuel rich conditions, maintenance of continuous slag flow and removal from the combustor, development of proper air cooling operating procedures, and determining component materials durability. The second major focus of the test effort was on environmental control, especially control of SO{sub 2} emissions. By using staged combustion, the NO{sub x} emissions were reduced by around 3/4 to 184 ppmv, with further reductions to 160 ppmv in the stack particulate scrubber. By injection of calcium based sorbents into the combustor, stack SO{sub 2} emissions were reduced by a maximum of of 58%. (VC)

  10. Advances in Information Barrier Design.

    SciTech Connect

    Williams, R. B.; Frame, K. C.; Landry, R. P.; MacArthur, D. W.; Smith, M. K.

    2005-01-01

    The concept of an information barrier, or IB, has been widely discussed for a number of years. An IB is used in a measurement system that contains classified information to prevent the release (either intentional or inadvertent) of the classified information while still allowing an inspecting party to reach independent conclusions as to the contents of a storage container. Typically, an IB would be used in a measurement system regime that requires the owner of certain storage containers to declare the contents of the containers (in unclassified terms) and an inspecting party to confirm this declaration. The IB allows the owner's declaration to be confirmed without releasing any classified information to the inspecting party. Most IB design concepts are based on two attribute measruement systems (AMSs) that were built and demonstrated in the US in 1999 and 2000. These IBs relied heavily on simple hardware implementations and performed well in a 'one-time' demonstration mode. However, implementation of an AMS in a long-term verification regime will place a different set of requirements on the entire AMS system - and the IB, in particular. In this paper, they will concentrate on the effects of changing constraints on IB design, new IB concepts that have been developed since the earlier demonstrations, and design concepts that have been developed within a number of related verification regimes.

  11. Combustor liner support assembly

    NASA Technical Reports Server (NTRS)

    Halila, Ely E. (Inventor)

    1994-01-01

    A support assembly for a gas turbine engine combustor includes an annular frame having a plurality of circumferentially spaced apart tenons, and an annular combustor liner disposed coaxially with the frame and including a plurality of circumferentially spaced apart tenons circumferentially adjoining respective ones of the frame tenons for radially and tangentially supporting the liner to the frame while allowing unrestrained differential thermal radial movement therebetween.

  12. Advanced space engine preliminary design

    NASA Technical Reports Server (NTRS)

    Cuffe, J. P. B.; Bradie, R. E.

    1973-01-01

    A preliminary design was completed for an O2/H2, 89 kN (20,000 lb) thrust staged combustion rocket engine that has a single-bell nozzle with an overall expansion ratio of 400:1. The engine has a best estimate vacuum specific impulse of 4623.8 N-s/kg (471.5 sec) at full thrust and mixture ratio = 6.0. The engine employs gear-driven, low pressure pumps to provide low NPSH capability while individual turbine-driven, high-speed main pumps provide the system pressures required for high-chamber pressure operation. The engine design dry weight for the fixed-nozzle configuration is 206.9 kg (456.3 lb). Engine overall length is 234 cm (92.1 in.). The extendible nozzle version has a stowed length of 141.5 cm (55.7 in.). Critical technology items in the development of the engine were defined. Development program plans and their costs for development, production, operation, and flight support of the ASE were established for minimum cost and minimum time programs.

  13. Small gas turbine combustor experimental study: Compliant metal/ceramic liner and performance evaluation

    NASA Technical Reports Server (NTRS)

    Acosta, W. A.; Norgren, C. T.

    1986-01-01

    Combustor research relating to the development of fuel efficient small gas turbine engines capable of meeting future commercial and military aviation needs is currently underway at NASA Lewis. As part of this combustor research, a basic reverse-flow combustor has been used to investigate advanced liner wall cooling techniques. Liner temperature, performance, and exhaust emissions of the experimental combustor utilizing compliant metal/ceramic liners were determined and compared with three previously reported combustors that featured: (1) splash film-cooled liner walls; (2) transpiration cooled liner walls; and (3) counter-flow film cooled panels.

  14. Advanced wing design survivability testing and results

    NASA Technical Reports Server (NTRS)

    Bruno, J.; Tobias, M.

    1992-01-01

    Composite wings on current operational aircraft are conservatively designed to account for stress/strain concentrations, and to assure specified damage tolerance. The technology that can lead to improved composite wing structures and associated structural efficiency is to increase design ultimate strain levels beyond their current limit of 3500 to 4000 micro-in/in to 6000 micro-in/in without sacrificing structural integrity, durability, damage tolerance, or survivability. Grumman, under the sponsorship of the Naval Air Development Center (NADC), has developed a high-strain composite wing design for a subsonic aircraft wing using novel and innovative design concepts and manufacturing methods, while maintaining a state-of-the-art fiber/resin system. The current advanced wing design effort addressed a tactical subsonic aircraft wing using previously developed, high-strain wing design concepts in conjunction with newer/emerging fiber and polymer matrix composite (PMC) materials to achieve the same goals, while reducing complexity. Two categories of advanced PMC materials were evaluated: toughened thermosets; and engineered thermoplastics. Advanced PMC materials offer the technological opportunity to take maximum advantage of improved material properties, physical characteristics, and tailorability to increase performance and survivability over current composite structure. Damage tolerance and survivability to various threats, in addition to structural integrity and durability, were key technical issues addressed during this study, and evaluated through test. This paper focuses on the live-fire testing, and the results performed to experimentally evaluate the survivability of the advanced wing design.

  15. Dish stirling solar receiver combustor test program

    NASA Technical Reports Server (NTRS)

    Bankston, C. P.; Back, L. H.

    1981-01-01

    The operational and energy transfer characteristics of the Dish Stirling Solar Receiver (DSSR) combustor/heat exchanger system was evaluated. The DSSR is designed to operate with fossil fuel augmentation utilizing a swirl combustor and cross flow heat exchanger consisting of a single row of 4 closely spaced tubes that are curved into a conical shape. The performance of the combustor/heat exchanger system without a Stirling engine was studied over a range of operating conditions and output levels using water as the working fluid. Results show that the combustor may be started under cold conditions, controlled safety, and operated at a constant air/fuel ratio (10 percent excess air) over the required range of firing rates. Furthermore, nondimensional heat transfer coefficients based on total heat transfer are plotted versus Reynolds number and compared with literature data taken for single rows of closely spaced tubes perpendicular to cross flow. The data show enhanced heat transfer for the present geometry and test conditions. Analysis of the results shows that the present system meets specified thermal requirements, thus verifying the feasibility of the DSSR combustor design for final prototype fabrication.

  16. LDV Measurements in an Annular Combustor Model

    NASA Technical Reports Server (NTRS)

    Barron, Dean A.

    1996-01-01

    This thesis covers the design and setup of a laser doppler velocimeter (LDV) system used to take velocity measurements in an annular combustor model. The annular combustor model is of contemporary design using 60 degree flat vane swirlers, producing a strong recirculation zone. Detailed measurements are taken of the swirler inlet air flow and of the downstream enclosed swirling flow. The laser system used is a two color, two component system set up in forward scatter. Detailed are some of the special considerations needed for LDV use in the confined turbulent flow of the combustor model. LDV measurements in a single swirler rig indicated that the flow changes radically in the first duct height. After this, a flow profile is set up and remains constant in shape. The magnitude of the velocities gradually decays due to viscous damping.

  17. Combustor flame flashback

    NASA Technical Reports Server (NTRS)

    Proctor, M. P.; Tien, J. S.

    1985-01-01

    A stainless steel, two-dimensional (rectangular), center-dump, premixed-prevaporized combustor with quartz window sidewalls for visual access was designed, built, and used to study flashback. A parametric study revealed that the flashback equivalence ratio decreased slightly as the inlet air temperature increased. It also indicated that the average premixer velocity and premixer wall temperature were not governing parameters of flashback. The steady-state velocity balance concept as the flashback mechanism was not supported. From visual observation several stages of burning were identified. High speed photography verified upstream flame propagation with the leading edge of the flame front near the premixer wall. Combustion instabilities (spontaneous pressure oscillations) were discovered during combustion at the dump plane and during flashback. The pressure oscillation frequency ranged from 40 to 80 Hz. The peak-to-peak amplitude (up to 1.4 psi) increased as the fuel/air equivalence ratio was increased attaining a maximum value just before flashback. The amplitude suddenly decreased when the flame stabilized in the premixer. The pressure oscillations were large enough to cause a local flow reversal. A simple test using ceramic fiber tufts indicated flow reversals existed at the premixer exit during flickering. It is suspected that flashback occurs through the premixer wall boundary layer flow reversal caused by combustion instability. A theoretical analysis of periodic flow in the premixing channel has been made. The theory supports the flow reversal mechanism.

  18. L-star pulsed coal combustor for residential space heating

    SciTech Connect

    Not Available

    1989-03-01

    This quarter, substantial improvement in the coal carbon conversion was achieved. Specifically, for a scaled-down version of the residential combustor, coal carbon conversions exceeding 97 percent were realized, when utilizing methane as carrier gas for the coal. Design changes include insulation of the combustor, introduction of a flame holder, combustion air preheat and presence of an obstructing plate at the combustor exhaust port. Only the first two changes contributed towards substantial improvement in coal conversion. In addition, monitoring of CH{sub 4} concentration in the exhaust gases gave a real time indication of the combustor performance. Finally, the results of experiments performed in this quarter contributed to design changes that have led to a combustor that has achieved the program goal of > 99 percent conversion of coal carbon. 5 figs., 2 tabs.

  19. Various advanced design projects promoting engineering education

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The Universities Space Research Association (USRA) Advanced Design Program (ADP) program promotes engineering education in the field of design by presenting students with challenging design projects drawn from actual NASA interests. In doing so, the program yields two very positive results. Firstly, the students gain a valuable experience that will prepare them for design problems with which they will be faced in their professional careers. Secondly, NASA is able to use the work done by students as an additional resource in meeting its own design objectives. The 1994 projects include: Universal Test Facility; Automated Protein Crystal Growth Facility; Stiffening of the ACES Deployable Space Boom; Launch System Design for Access to Space; LH2 Fuel Tank Design for SSTO Vehicle; and Feed System Design for a Reduced Pressure Tank.

  20. Advanced turbine systems program: Conceptual design and product development. Topical report, November 1993

    SciTech Connect

    Wilken, L.S.

    1994-01-01

    This report has been prepared by Solar Turbines Incorporated (Solar) in accordance with Task 2 of the Advanced Turbine Systems (ATS) Contract. This report addresses only the work that will be performed under Task 8 (Design and Test of Critical Components) of the Contract. The discussion is divided into four general sections: Project Description; Potential Environmental Impacts; Required Permits and Licenses; and Environmental, Safety and Health (ES and H) Agency Contact Information. As described in further detail herein, the activities to occur during the project (i.e., Task 8) consists primarily of short duration testing of laboratory-scale components (or portions of components) for the ATS program. The testing involved will fall in the following general categories: recuperator, combustor, and blade/airfoil cooling. All activities contemplated will occur at existing facilities. Solar believes that the information in this report supports the conclusion that no significant environmental impacts will be associated with the project.

  1. Advanced design concepts for shuttle airframe structure

    NASA Technical Reports Server (NTRS)

    Card, M. F.; Davis, J. G., Jr.; Shideler, J. L.

    1972-01-01

    The development of weight-saving advanced design concepts for shuttle airframe structure is presented. Design concepts under investigation employ selective composite reinforcement and/or efficient geometric arrangements. An effort to develop metallic panel designs which exploit the relaxation of smooth external-surface requirements for skin structure is reviewed. Available highlights from research and development studies which investigate the application of composite reinforcement to the design of two types of fuselage panels, a shear web, a large fuselage frame, and a landing-gear-door assembly are presented. Preliminary results from these studies suggest weight savings of 25 percent can be obtained.

  2. Advanced Subsonic Airplane Design and Economic Studies

    NASA Technical Reports Server (NTRS)

    Liebeck, Robert H.; Andrastek, Donald A.; Chau, Johnny; Girvin, Raquel; Lyon, Roger; Rawdon, Blaine K.; Scott, Paul W.; Wright, Robert A.

    1995-01-01

    A study was made to examine the effect of advanced technology engines on the performance of subsonic airplanes and provide a vision of the potential which these advanced engines offered. The year 2005 was selected as the entry-into-service (EIS) date for engine/airframe combination. A set of four airplane classes (passenger and design range combinations) that were envisioned to span the needs for the 2005 EIS period were defined. The airframes for all classes were designed and sized using 2005 EIS advanced technology. Two airplanes were designed and sized for each class: one using current technology (1995) engines to provide a baseline, and one using advanced technology (2005) engines. The resulting engine/airframe combinations were compared and evaluated on the basis on sensitivity to basic engine performance parameters (e.g. SFC and engine weight) as well as DOC+I. The advanced technology engines provided significant reductions in fuel burn, weight, and wing area. Average values were as follows: reduction in fuel burn = 18%, reduction in wing area = 7%, and reduction in TOGW = 9%. Average DOC+I reduction was 3.5% using the pricing model based on payload-range index and 5% using the pricing model based on airframe weight. Noise and emissions were not considered.

  3. Advanced wind turbine design studies: Advanced conceptual study. Final report

    SciTech Connect

    Hughes, P; Sherwin, R

    1994-08-01

    In conjunction with the US Department of Energy and the National Renewable Energy Laboratory`s Advanced Wind Turbine Program, the Atlantic Orient Corporation developed preliminary designs for the next generation of wind turbines. These 50 kW and 350 kW turbines are based upon the concept of simplicity. By adhering to a design philosophy that emphasizes simplicity, we project that these turbines will produce energy at extremely competitive rates which will unlock the potential of wind energy domestically and internationally. The program consisted of three distinct phases. First, we evaluated the operational history of the Enertech 44 series wind turbines. As a result of this evaluation, we developed, in the second phase, a preliminary design for a new 50 kW turbine for the near-term market. In the third phase, we took a clean-sheet-of-paper approach to designing a 350 kW turbine focused on the mid-1990s utility market that incorporated past experience and advanced technology.

  4. Advanced wind turbine design studies: Advanced conceptual study

    NASA Astrophysics Data System (ADS)

    Hughes, P.; Sherwin, R.

    1994-08-01

    In conjunction with the US Department of Energy and the National Renewable Energy Laboratory's Advanced Wind Turbine Program, the Atlantic Orient Corporation developed preliminary designs for the next generation of wind turbines. These 50 kW and 350 kW turbines are based upon the concept of simplicity. By adhering to a design philosophy that emphasizes simplicity, we project that these turbines will produce energy at extremely competitive rates which will unlock the potential of wind energy domestically and internationally. The program consisted of three distinct phases. First, we evaluated the operational history of the Enertech 44 series wind turbines. As a result of this evaluation, we developed, in the second phase, a preliminary design for a new 50 kW turbine for the near-term market. In the third phase, we took a clean-sheet-of-paper approach to designing a 350 kW turbine focused on the mid-1990s utility market that incorporated past experience and advanced technology.

  5. Simulator design for advanced ISDN satellite design and experiments

    NASA Technical Reports Server (NTRS)

    Pepin, Gerald R.

    1992-01-01

    This simulation design task completion report documents the simulation techniques associated with the network models of both the Interim Service ISDN (integrated services digital network) Satellite (ISIS) and the Full Service ISDN Satellite (FSIS) architectures. The ISIS network model design represents satellite systems like the Advanced Communication Technology Satellite (ACTS) orbiting switch. The FSIS architecture, the ultimate aim of this element of the Satellite Communications Applications Research (SCAR) program, moves all control and switching functions on-board the next generation ISDN communication satellite. The technical and operational parameters for the advanced ISDN communications satellite design will be obtained from the simulation of ISIS and FSIS engineering software models for their major subsystems. Discrete events simulation experiments will be performed with these models using various traffic scenarios, design parameters and operational procedures. The data from these simulations will be used to determine the engineering parameters for the advanced ISDN communications satellite.

  6. Development of a coal fired pulse combustor for residential space heating. Phase I, Final report

    SciTech Connect

    1988-04-01

    This report presents the results of the first phase of a program for the development of a coal-fired residential combustion system. This phase consisted of the design, fabrication, testing, and evaluation of an advanced pulse combustor sized for residential space heating requirements. The objective was to develop an advanced pulse coal combustor at the {approximately} 100,000 Btu/hr scale that can be integrated into a packaged space heating system for small residential applications. The strategy for the development effort included the scale down of the feasibility unit from 1-2 MMBtu/hr to 100,000 Btu/hr to establish a baseline for isolating the effect of scale-down and new chamber configurations separately. Initial focus at the residential scale was concentrated on methods of fuel injection and atomization in a bare metal unit. This was followed by incorporating changes to the advanced chamber designs and testing of refractory-lined units. Multi-fuel capability for firing oil or gas as a secondary fuel was also established. Upon completion of the configuration and component testing, an optimum configuration would be selected for integrated testing of the pulse combustor unit. The strategy also defined the use of Dry Ultrafine Coal (DUC) for Phases 1 and 2 of the development program with CWM firing to be a product improvement activity for a later phase of the program.

  7. 50% Advanced Energy Design Guides: Preprint

    SciTech Connect

    Bonnema, E.; Leach, M.; Pless, S.; Liu, B.; Wang, W.; Thornton, B.; Williams, J.

    2012-07-01

    This paper presents the process, methodology, and assumptions for the development of the 50% Energy Savings Advanced Energy Design Guides (AEDGs), a design guidance document that provides specific recommendations for achieving 50% energy savings above the requirements of ANSI/ASHRAE/IESNA Standard 90.1-2004 in four building types: (1) Small to medium office buildings, (2) K-12 school buildings, (3) Medium to big box retail buildings, (4) Large hospital buildings.

  8. Experimental clean combustor program, phase 1. [aircraft exhaust/gas analysis - gas turbine engines

    NASA Technical Reports Server (NTRS)

    Roberts, R.; Peduzzi, A.; Vitti, G. E.

    1975-01-01

    A program of screening three low emission combustors for conventional takeoff and landing, by testing and analyzing thirty-two configurations is presented. Configurations were tested that met the emission goals at idle operating conditions for carbon monoxide and for unburned hydrocarbons (emission index values of 20 and 4, respectively). Configurations were also tested that met a smoke number goal of 15 at sea-level take-off conditions. None of the configurations met the goal for oxides of nitrogen emissions at sea-level take-off conditions. The best configurations demonstrated oxide of nitrogen emission levels that were approximately 61 percent lower than those produced by the JT9D-7 engine, but these levels were still approximately 24 percent above the goal of an emission index level of 10. Additional combustor performance characteristics, including lean blowout, exit temperature pattern factor and radial profile, pressure loss, altitude stability, and altitude relight characteristics were documented. The results indicate the need for significant improvement in the altitude stability and relight characteristics. In addition to the basic program for current aircraft engine combustors, seventeen combustor configurations were evaluated for advanced supersonic technology applications. The configurations were tested at cruise conditions, and a conceptual design was evolved.

  9. Achieving improved cycle efficiency via pressure gain combustors

    SciTech Connect

    Gemmen, R.S.; Janus, M.C.; Richards, G.A.; Norton, T.S.; Rogers, W.A.

    1995-04-01

    As part of the Department of Energy`s Advanced Gas Turbine Systems Program, an investigation is being performed to evaluate ``pressure gain`` combustion systems for gas turbine applications. This paper presents experimental pressure gain and pollutant emission data from such combustion systems. Numerical predictions for certain combustor geometries are also presented. It is reported that for suitable aerovalved pulse combustor geometries studied experimentally, an overall combustor pressure gain of nearly 1 percent can be achieved. It is also shown that for one combustion system operating under typical gas turbine conditions, NO{sub x} and CO emmissions, are about 30 ppmv and 8 ppmv, respectively.

  10. Technical Workshop: Advanced Helicopter Cockpit Design

    NASA Technical Reports Server (NTRS)

    Hemingway, J. C. (Editor); Callas, G. P. (Editor)

    1984-01-01

    Information processing demands on both civilian and military aircrews have increased enormously as rotorcraft have come to be used for adverse weather, day/night, and remote area missions. Applied psychology, engineering, or operational research for future helicopter cockpit design criteria were identified. Three areas were addressed: (1) operational requirements, (2) advanced avionics, and (3) man-system integration.

  11. Advanced EVA system design requirements study

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Design requirements and criteria for the Space Station Advanced Extravehicular Activity System (EVAS) including crew enclosures, portable life support systems, maneuvering propulsion systems, and related extravehicular activity (EVA) support equipment were defined and established. The EVA mission requirements, environments, and medical and physiological requirements, as well as opertional, procedures, and training issues were considered.

  12. New engine and advanced component design

    SciTech Connect

    Not Available

    1990-01-01

    This book contains the proceedings on new engine and advance component design. Topics covered include: development of low emission high performance four valve engines, the effect of engine build options on powerplant inertias, silicon nitride turbocharger rotor for high performance automotive engines and development of Toyota reflex Burn (TRB) system in DI diesel.

  13. Hypersonic research engine project. Phase 2: Some combustor test results of NASA aerothermodynamic integration model

    NASA Technical Reports Server (NTRS)

    Sun, Y. H.; Gaede, A. E.; Sainio, W. C.

    1975-01-01

    Combustor test results of the NASA Aerothermodynamic Integration Model are presented of a ramjet engine developed for operation between Mach 3 and 8. Ground-based and flight experiments which provide the data required to advance the technology of hypersonic air-breathing propulsion systems as well as to evaluate facility and testing techniques are described. The engine was tested with synthetic air at Mach 5, 6, and 7. The hydrogen fuel was heated to 1500 R prior to injection to simulate a regeneratively cooled system. Combustor efficiencies up to 95 percent at Mach 6 were achieved. Combustor process in terms of effectiveness, pressure integral factor, total pressure recovery and Crocco's pressure-area relationship are presented and discussed. Interactions between inlet-combustor, combustor stages, combustor-nozzle, and the effects of altitude, combustor step, and struts are observed and analyzed.

  14. Optical Diagnosis of Gas Turbine Combustors Being Conducted

    NASA Technical Reports Server (NTRS)

    Hicks, Yolanda R.; Locke, Randy J.; Anderson, Robert C.; DeGroot, Wilhelmus A.

    2001-01-01

    Researchers at the NASA Glenn Research Center, in collaboration with industry, are reducing gas turbine engine emissions by studying visually the air-fuel interactions and combustion processes in combustors. This is especially critical for next generation engines that, in order to be more fuel-efficient, operate at higher temperatures and pressures than the current fleet engines. Optically based experiments were conducted in support of the Ultra-Efficient Engine Technology program in Glenn's unique, world-class, advanced subsonic combustion rig (ASCR) facility. The ASCR can supply air and jet fuel at the flow rates, temperatures, and pressures that simulate the conditions expected in the combustors of high-performance, civilian aircraft engines. In addition, this facility is large enough to support true sectors ("pie" slices of a full annular combustor). Sectors enable one to test true shapes rather than rectangular approximations of the actual hardware. Therefore, there is no compromise to actual engine geometry. A schematic drawing of the sector test stand is shown. The test hardware is mounted just upstream of the instrumentation section. The test stand can accommodate hardware up to 0.76-m diameter by 1.2-m long; thus sectors or small full annular combustors can be examined in this facility. Planar (two-dimensional) imaging using laser-induced fluorescence and Mie scattering, chemiluminescence, and video imagery were obtained for a variety of engine cycle conditions. The hardware tested was a double annular sector (two adjacent fuel injectors aligned radially) representing approximately 15 of a full annular combustor. An example of the two-dimensional data obtained for this configuration is also shown. The fluorescence data show the location of fuel and hydroxyl radical (OH) along the centerline of the fuel injectors. The chemiluminescence data show C2 within the total observable volume. The top row of this figure shows images obtained at an engine low

  15. Gas turbine topping combustor

    DOEpatents

    Beer, Janos; Dowdy, Thomas E.; Bachovchin, Dennis M.

    1997-01-01

    A combustor for burning a mixture of fuel and air in a rich combustion zone, in which the fuel bound nitrogen in converted to molecular nitrogen. The fuel rich combustion is followed by lean combustion. The products of combustion from the lean combustion are rapidly quenched so as to convert the fuel bound nitrogen to molecular nitrogen without forming NOx. The combustor has an air radial swirler that directs the air radially inward while swirling it in the circumferential direction and a radial fuel swirler that directs the fuel radially outward while swirling it in the same circumferential direction, thereby promoting vigorous mixing of the fuel and air. The air inlet has a variable flow area that is responsive to variations in the heating value of the fuel, which may be a coal-derived fuel gas. A diverging passage in the combustor in front of a bluff body causes the fuel/air mixture to recirculate with the rich combustion zone.

  16. Advanced turbine systems (ATS) program conceptual design and product development. Quarterly report, September 1 - November 30, 1994

    SciTech Connect

    1994-12-31

    Achieving the advanced turbine system goals of 60% efficiency, 8 ppmvd NOx, and 10% electric power cost reduction imposes competing characteristics on the gas turbine system: the turbine inlet temperature must increase, although this will lead to increased NOx emission. Improved coating and materials along with creative combustor design can result in solutions. The program is focused on two specific products: a 70 MW class industrial gas turbine based on GE90 core technology utilizing an innovative air cooling methodology, and a 200 MW class utility gas turbine based on an advanced GE heavy duty machines utilizing advanced cooling and enhancement in component efficiency. This report reports on tasks 3-8 for the industrial ATS and the utility ATS. Some impingement heat transfer results are given.

  17. Combustor and method for purging a combustor

    DOEpatents

    Berry, Jonathan Dwight; Hughes, Michael John

    2015-06-09

    A combustor includes an end cap. The end cap includes a first surface and a second surface downstream from the first surface, a shroud that circumferentially surrounds at least a portion of the first and second surfaces, a plate that extends radially within the shroud, a plurality of tubes that extend through the plate and the first and second surfaces, and a first purge port that extends through one or more of the plurality of tubes, wherein the purge port is axially aligned with the plate.

  18. The Advanced Design Program at Penn State

    NASA Technical Reports Server (NTRS)

    Thompson, Roger C.; Melton, Robert G.

    1992-01-01

    An account is given of the NASA/USRA Advanced Design Program (ADP) instituted by Penn State for students in space-related fields. ADP class instruction is structured in such a way as to simulate the working environment in which design engineers from different disciplines must interact, at various levels, in the course of defining a spacecraft-related system. Student groups are assigned a mission objective, for which they are to complete a preliminary design encompassing all aspects of the mission from launch to recovery. Two major writen reports are required from each group.

  19. Low NOx heavy fuel combustor concept program

    NASA Technical Reports Server (NTRS)

    White, D. J.; Lecren, R. T.; Batakis, A. P.

    1981-01-01

    A total of twelve low NOx combustor configurations, embodying three different combustion concepts, were designed and fabricated as modular units. These configurations were evaluated experimentally for exhaust emission levels and for mechanical integrity. Emissions data were obtained in depth on two of the configurations.

  20. Steam reformer with catalytic combustor

    NASA Technical Reports Server (NTRS)

    Voecks, Gerald E. (Inventor)

    1990-01-01

    A steam reformer is disclosed having an annular steam reforming catalyst bed formed by concentric cylinders and having a catalytic combustor located at the center of the innermost cylinder. Fuel is fed into the interior of the catalytic combustor and air is directed at the top of the combustor, creating a catalytic reaction which provides sufficient heat so as to maintain the catalytic reaction in the steam reforming catalyst bed. Alternatively, air is fed into the interior of the catalytic combustor and a fuel mixture is directed at the top. The catalytic combustor provides enhanced radiant and convective heat transfer to the reformer catalyst bed.

  1. Steam reformer with catalytic combustor

    DOEpatents

    Voecks, Gerald E.

    1990-03-20

    A steam reformer is disclosed having an annular steam reforming catalyst bed formed by concentric cylinders and having a catalytic combustor located at the center of the innermost cylinder. Fuel is fed into the interior of the catalytic combustor and air is directed at the top of the combustor, creating a catalytic reaction which provides sufficient heat so as to maintain the catalytic reaction in the steam reforming catalyst bed. Alternatively, air is fed into the interior of the catalytic combustor and a fuel mixture is directed at the top. The catalytic combustor provides enhanced radiant and convective heat transfer to the reformer catalyst bed.

  2. The design of repairable advanced composite structures

    NASA Technical Reports Server (NTRS)

    Hart-Smith, L. J.

    1985-01-01

    This paper addresses the repair of advanced composite structures by mechanical fasteners or by adhesive bonding. It is shown that many of today's composite designs are unreasonably difficult to repair. Conversely, the knowledge to design repairable structures is already available, if only it is applied during the initial design stage. Bolted or riveted repairs require only the avoidance of extremely orthotropic composite fiber patterns; those near the quasi-isotropic layup are the most suitable. Mildly orthotropic fiber patterns are appropriate for structures in which there is a dominant load direction. Thick composite structures are shown to require bolted or riveted repairs while thin structures favor adhesively bonded permanent repairs, although provisions can be easily made for temporary mechanical repairs. The reasons why integrally stiffened cocured composite designs are usually impractical to repair are explained and alternative repairable design concepts are presented.

  3. Mirror Advanced Reactor Study interim design report

    SciTech Connect

    Not Available

    1983-04-01

    The status of the design of a tenth-of-a-kind commercial tandem-mirror fusion reactor is described at the midpoint of a two-year study. When completed, the design is to serve as a strategic goal for the mirror fusion program. The main objectives of the Mirror Advanced Reactor Study (MARS) are: (1) to design an attractive tandem-mirror fusion reactor producing electricity and synfuels (in alternate versions), (2) to identify key development and technology needs, and (3) to exploit the potential of fusion for safety, low activation, and simple disposal of radioactive waste. In the first year we have emphasized physics and engineering of the central cell and physics of the end cell. Design optimization and trade studies are continuing, and we expect additional modifications in the end cells to further improve the performance of the final design.

  4. Preliminary investigation of a two-zone swirl flow combustor

    NASA Technical Reports Server (NTRS)

    Biaglow, J. A.; Johnson, S. M.; Smith, J. M.

    1984-01-01

    The effect of full-annular swirling-flow on a flow-zone combustor design is investigated. Swirl flow angles of 25, 35, and 45 degrees were investigated in a combustor design envelope typical of those used in modern engines. The two-zone combustor had 24 pilot-zone fuel injectors and 24 main-fuel injectors located in the centerbody between the pilot and swirl passage. Combustor performance was determined at idle, and two parametric 589 K inlet temperature conditions. Combustor performance was highest with the 45 degree swirl vane design; at the idle condition, combustion efficiency was 99.5 percent. The 45 degree swirl vane also produced the lowest pattern factor of the three angles and showed a combustor lean blowout limit below a 0.001 fuel-air ratio. Combustor total pressure drop varied from a low of 4.6 percent for the 25 degree swirl to a high of 4.9 percent for the 45 degree swirl.

  5. Combustor technology for future small gas turbine aircraft

    NASA Technical Reports Server (NTRS)

    Lyons, Valerie J.; Niedzwiecki, Richard W.

    1993-01-01

    Future engine cycles proposed for advanced small gas turbine engines will increase the severity of the operating conditions of the combustor. These cycles call for increased overall engine pressure ratios which increase combustor inlet pressure and temperature. Further, the temperature rise through the combustor and the corresponding exit temperature also increase. Future combustor technology needs for small gas turbine engines is described. New fuel injectors with large turndown ratios which produce uniform circumferential and radial temperature patterns will be required. Uniform burning will be of greater importance because hot gas temperatures will approach turbine material limits. The higher combustion temperatures and increased radiation at high pressures will put a greater heat load on the combustor liners. At the same time, less cooling air will be available as more of the air will be used for combustion. Thus, improved cooling concepts and/or materials requiring little or no direct cooling will be required. Although presently there are no requirements for emissions levels from small gas turbine engines, regulation is expected in the near future. This will require the development of low emission combustors. In particular, nitrogen oxides will increase substantially if new technologies limiting their formation are not evolved and implemented. For example, staged combustion employing lean, premixed/prevaporized, lean direct injection, or rich burn-quick quench-lean burn concepts could replace conventional single stage combustors.

  6. Combustor burner vanelets

    DOEpatents

    Lacy, Benjamin [Greer, SC; Varatharajan, Balachandar [Loveland, OH; Kraemer, Gilbert Otto [Greer, SC; Yilmaz, Ertan [Albany, NY; Zuo, Baifang [Simpsonville, SC

    2012-02-14

    The present application provides a burner for use with a combustor of a gas turbine engine. The burner may include a center hub, a shroud, a pair of fuel vanes extending from the center hub to the shroud, and a vanelet extending from the center hub and/or the shroud and positioned between the pair of fuel vanes.

  7. Design of an advanced flight planning system

    NASA Technical Reports Server (NTRS)

    Sorensen, J. A.; Goka, T.

    1985-01-01

    The demand for both fuel conservation and four-dimensional traffic management require that the preflight planning process be designed to account for advances in airborne flight management and weather forecasting. The steps and issues in designing such an advanced flight planning system are presented. Focus is placed on the different optimization options for generating the three-dimensional reference path. For the cruise phase, one can use predefined jet routes, direct routes based on a network of evenly spaced grid points, or a network where the grid points are existing navaid locations. Each choice has its own problem in determining an optimum solution. Finding the reference path is further complicated by choice of cruise altitude levels, use of a time-varying weather field, and requiring a fixed time-of-arrival (four-dimensional problem).

  8. Advanced Extravehicular Mobility Unit Informatics Software Design

    NASA Technical Reports Server (NTRS)

    Wright, Theodore

    2014-01-01

    This is a description of the software design for the 2013 edition of the Advanced Extravehicular Mobility Unit (AEMU) Informatics computer assembly. The Informatics system is an optional part of the space suit assembly. It adds a graphical interface for displaying suit status, timelines, procedures, and caution and warning information. In the future it will display maps with GPS position data, and video and still images captured by the astronaut.

  9. Nonintrusive laser-induced imaging for speciation and patternation in high-pressure gas turbine combustors

    NASA Astrophysics Data System (ADS)

    Locke, Randy J.; Zaller, Michelle M.; Hicks, Yolanda R.; Anderson, Robert C.

    1999-10-01

    The next generation of ga turbine combustors for aerospace applications will be required to meet increasingly stringent constraints on fuel efficiency, noise abatement, and emissions. The power plants being designed to meet these constraints will operate at extreme conditions of temperature and pressure, thereby generating unique challenges to the previously employed diagnostic methodologies. Current efforts at NASA Glenn Research Center GRC utilize optically accessible, high-pressure flametubes and sector combustor rigs to probe, via advanced nonintrusive laser techniques, the complex flowfields encountered in advanced combustor designs. The fuel-air mixing process is of particular concern for lowering NOx emissions generated in lean, premixed engine concepts. Using planar laser-induced fluorescence we have obtained real- time, detailed imaging of the fuel spray distribution for a number of fuel injectors over a wide range of operational conditions that closely match those expected in the proposed propulsion systems. Using a novel combination of planar imaging of fuel fluorescence and computational analysis that allows an examination of the flowfield from any perspective, we have produced spatially and temporally resolved fuel-air distribution maps. These maps provide detailed insight into the fuel injection process at actual conditions never before possible, thereby greatly enhancing the evaluation of fuel injector performance and combustion phenomena.

  10. Effects of radial and circumferential inlet velocity profile distortions on performance of a short-length double-annular ram induction combustor

    NASA Technical Reports Server (NTRS)

    Schultz, D. F.; Perkins, P. J.

    1972-01-01

    Inlet air velocity profile tests were conducted on a full-scale short-length 102-centimeter-diameter annual combustor designed for advanced gas turbine engine applications. The inlet profiles studied include radial distortions that were center peaked, and tip peaked, as well as a circumferential distortion which was center peaked for one-third of the circumference and flat for the other two-thirds. An increase in combustor pressure loss was the most significant effect of the radial air velocity distortions. With the circumferential distortion, exit temperature pattern factor doubled when compared to a flat velocity profile.

  11. Advanced control design for hybrid turboelectric vehicle

    NASA Astrophysics Data System (ADS)

    Abban, Joseph; Norvell, Johnesta; Momoh, James A.

    1995-08-01

    The new environment standards are a challenge and opportunity for industry and government who manufacture and operate urban mass transient vehicles. A research investigation to provide control scheme for efficient power management of the vehicle is in progress. Different design requirements using functional analysis and trade studies of alternate power sources and controls have been performed. The design issues include portability, weight and emission/fuel efficiency of induction motor, permanent magnet and battery. A strategic design scheme to manage power requirements using advanced control systems is presented. It exploits fuzzy logic, technology and rule based decision support scheme. The benefits of our study will enhance the economic and technical feasibility of technological needs to provide low emission/fuel efficient urban mass transit bus. The design team includes undergraduate researchers in our department. Sample results using NASA HTEV simulation tool are presented.

  12. Advanced control design for hybrid turboelectric vehicle

    NASA Technical Reports Server (NTRS)

    Abban, Joseph; Norvell, Johnesta; Momoh, James A.

    1995-01-01

    The new environment standards are a challenge and opportunity for industry and government who manufacture and operate urban mass transient vehicles. A research investigation to provide control scheme for efficient power management of the vehicle is in progress. Different design requirements using functional analysis and trade studies of alternate power sources and controls have been performed. The design issues include portability, weight and emission/fuel efficiency of induction motor, permanent magnet and battery. A strategic design scheme to manage power requirements using advanced control systems is presented. It exploits fuzzy logic, technology and rule based decision support scheme. The benefits of our study will enhance the economic and technical feasibility of technological needs to provide low emission/fuel efficient urban mass transit bus. The design team includes undergraduate researchers in our department. Sample results using NASA HTEV simulation tool are presented.

  13. ESD protection design for advanced CMOS

    NASA Astrophysics Data System (ADS)

    Huang, Jin B.; Wang, Gewen

    2001-10-01

    ESD effects in integrated circuits have become a major concern as today's technologies shrink to sub-micron/deep- sub-micron dimensions. The thinner gate oxide and shallower junction depth used in the advanced technologies make them very vulnerable to ESD damages. The advanced techniques like silicidation and STI (shallow trench insulation) used for improving other device performances make ESD design even more challenging. For non-silicided technologies, a certain DCGS (drain contact to gate edge spacing) is needed to achieve ESD hardness for nMOS output drivers and nMOS protection transistors. The typical DCGS values are 4-5um and 2-3um for 0.5um and 0.25um CMOS, respectively. The silicidation reduces the ballast resistance provided by DCGS with at least a factor of 10. As a result, scaling of the ESD performance with device width is lost and even zero ESD performance is reported for standard silicided devices. The device level ESD design is focused in this paper, which includes GGNMOS (gate grounded NMOS) and GCNMOS (gate coupled NMOS). The device level ESD testing including TLP (transmission line pulse) is given. Several ESD issues caused by advanced technologies have been pointed out. The possible solutions have been developed and summarized including silicide blocking, process optimization, back-end ballasting, and new protection scheme, dummy gate/n-well resistor ballsting, etc. Some of them require process cost increase, and others provide novel, compact, and simple design but involving royalty/IP (intellectual property) issue. Circuit level ESD design and layout design considerations are covered. The top-level ESD protection strategies are also given.

  14. SiC Recession Due to SiO2 Scale Volatility Under Combustor Conditions

    NASA Technical Reports Server (NTRS)

    Robinson, Raymond Craig

    1997-01-01

    One of today's most important and challenging technological problems is the development of advanced materials and processes required to design and build a fleet of supersonic High Speed Civil Transport (HSCT) airliners, a follow-up to the Concorde SST. The innovative combustor designs required for HSCT engines will need high-temperature materials with long-term environmental stability. Higher combustor liner temperatures than today's engines and the need for lightweight materials will require the use of advanced ceramic-matrix composites (CMC's) in hot-section components. The HSCT is just one example being used to demonstrate the need for such materials. This thesis evaluates silicon carbide (SiC) as a potential base material for HSCT and other similar applications. Key issues are the environmental durability for the materials of interest. One of the leading combustor design schemes leads to an environment which will contain both oxidizing and reducing gas mixtures. The concern is that these environments may affect the stability of the silica (SiO2) scale on which SiC depends for environmental protection. A unique High Pressure Burner Rig (HPBR) was developed to simulate the combustor conditions of future gas turbine engines, and a series of tests were conducted on commercially available SiC material. These tests are intended as a feasibility study for the use of these materials in applications such as the HSCT. Linear weight loss and surface recession of the SiC is observed as a result of SiO2 volatility for both fuel-lean and fuel-rich gas mixtures. These observations are compared and agree well with thermogravimetric analysis (TGA) experiments. A strong Arrhenius-type temperature dependence exists. In addition, the secondary dependencies of pressure and gas velocity are defined. As a result, a model is developed to enable extrapolation to points outside the experimental space of the burner rig, and in particular, to potential gas turbine engine conditions.

  15. Advanced turbine systems: Studies and conceptual design

    SciTech Connect

    van der Linden, S.; Gnaedig, G.; Kreitmeier, F.

    1993-11-01

    The ABB selection for the Advanced Turbine System (ATS) includes advanced developments especially in the hot gas path of the combustion turbine and new state-of-the-art units such as the steam turbine and the HRSG. The increase in efficiency by more than 10% multiplicative compared to current designs will be based on: (1) Turbine Inlet Temperature Increase; (2) New Cooling Techniques for Stationary and Rotating Parts; and New Materials. Present, projected component improvements that will be introduced with the above mentioned issues will yield improved CCSC turbine performance, which will drive the ATS selected gas-fired reference CC power plant to 6 % LHV or better. The decrease in emission levels requires a careful optimization of the cycle design, where cooling air consumption has to be minimized. All interfaces of the individual systems in the complete CC Plant need careful checks, especially to avoid unnecessary margins in the individual designs. This study is an important step pointing out the feasibility of the ATS program with realistic goals set by DOE, which, however, will present challenges for Phase II time schedule of 18 months. With the approach outlined in this study and close cooperation with DOE, ATS program success can be achieved to deliver low emissions and low cost of electricity by the year 2002. The ABB conceptual design and step approach will lead to early component demonstration which will help accelerate the overall program objectives.

  16. Advanced heat receiver conceptual design study

    NASA Technical Reports Server (NTRS)

    Kesseli, James; Saunders, Roger; Batchelder, Gary

    1988-01-01

    Solar Dynamic space power systems are candidate electrical power generating systems for future NASA missions. One of the key components of the solar dynamic power system is the solar receiver/thermal energy storage (TES) subsystem. Receiver development was conducted by NASA in the late 1960's and since then a very limited amount of work has been done in this area. Consequently the state of the art (SOA) receivers designed for the IOC space station are large and massive. The objective of the Advanced Heat Receiver Conceptual Design Study is to conceive and analyze advanced high temperature solar dynamic Brayton and Stirling receivers. The goal is to generate innovative receiver concepts that are half of the mass, smaller, and more efficient than the SOA. It is also necessary that these innovative receivers offer ease of manufacturing, less structural complexity and fewer thermal stress problems. Advanced Brayton and Stirling receiver storage units are proposed and analyzed in this study which can potentially meet these goals.

  17. Exhaust emissions of a double annular combustor: Parametric study

    NASA Technical Reports Server (NTRS)

    Schultz, D. F.

    1974-01-01

    A full scale double-annular ram-induction combustor designed for Mach 3.0 cruise operation was tested. Emissions of oxides of nitrogen, carbon monoxide, unburned hydrocarbons, and smoke were measured over a range of combustor operating variables including reference velocity, inlet air temperature and pressure, and exit average temperature. ASTM Jet-A fuel was used for these tests. An equation is provided relating oxides of nitrogen emissions as a function of the combustor, operating variables. A small effect of radial fuel staging on reducing exhaust emissions (which were originally quite low) is demonstrated.

  18. Low NOx, Lean Direct Wall Injection Combustor Concept Developed

    NASA Technical Reports Server (NTRS)

    Tacina, Robert R.; Wey, Changlie; Choi, Kyung J.

    2003-01-01

    The low-emissions combustor development at the NASA Glenn Research Center is directed toward advanced high-pressure aircraft gas turbine applications. The emphasis of this research is to reduce nitrogen oxides (NOx) at high-power conditions and to maintain carbon monoxide and unburned hydrocarbons at their current low levels at low-power conditions. Low-NOx combustors can be classified into rich burn and lean burn concepts. Lean burn combustors can be further classified into lean-premixed-prevaporized (LPP) and lean direct injection (LDI) combustors. In both concepts, all the combustor air, except for liner cooling flow, enters through the combustor dome so that the combustion occurs at the lowest possible flame temperature. The LPP concept has been shown to have the lowest NOx emissions, but for advanced high-pressure-ratio engines, the possibly of autoignition or flashback precludes its use. LDI differs from LPP in that the fuel is injected directly into the flame zone and, thus, does not have the potential for autoignition or flashback and should have greater stability. However, since it is not premixed and prevaporized, the key is good atomization and mixing of the fuel quickly and uniformly so that flame temperatures are low and NOx formation levels are comparable to those of LPP.

  19. Fabrication of advanced design (grooved) cermet anodes

    NASA Astrophysics Data System (ADS)

    Windisch, C. F., Jr.; Huettig, F. R.

    1993-05-01

    Attempts were made to fabricate full-size anodes with advanced, or grooved, design using isostatic pressing, slip casting injection molding. Of the three approaches, isostatic pressing produced an anode with dimensions nearest to the target specifications, without serious macroscopic flaws. This approach is considered the most promising for making advanced anodes for aluminum smelting. However, significant work still remains to optimize the physical properties and microstructure of the anode, both of which were significantly different from that of previous anodes. Injection molding and slip casting yielded anode materials with serious deficiencies, including cracks and holes. Injection molding gave cermet material with the best intrinsic microstructure, i.e., the microstructure of the material between macroscopic flaws was very similar to that of anodes previously made at PNL. The reason for the similarity may have to do with amount of residual binder in the material prior to sintering.

  20. Fabrication of advanced design (grooved) cermet anodes

    SciTech Connect

    Windisch, C.F. Jr. ); Huettig, F.R. )

    1993-05-01

    Attempts were made to fabricate full-size anodes with advanced, or grooved, design using isostatic pressing, slip casting injection molding. Of the three approaches, isostatic pressing produced an anode with dimensions nearest to the target specifications, without serious macroscopic flaws. This approach is considered the most promising for making advanced anodes for aluminum smelting. However, significant work still remains to optimize the physical properties and microstructure of the anode, both of which were significantly different from that of previous anodes. Injection molding and slip casting yielded anode materials with serious deficiencies, including cracks and holes. Injection molding gave cermet material with the best intrinsic microstructure, i.e., the microstructure of the material between macroscopic flaws was very similar to that of anodes previously made at PNL. Reason for the similarity may have to do with amount of residual binder in the material prior to sintering.

  1. Advanced Control Considerations for Turbofan Engine Design

    NASA Technical Reports Server (NTRS)

    Connolly, Joseph W.; Csank, Jeffrey T.; Chicatelli, Amy

    2016-01-01

    This paper covers the application of a model-based engine control (MBEC) methodology featuring a self tuning on-board model for an aircraft turbofan engine simulation. The nonlinear engine model is capable of modeling realistic engine performance, allowing for a verification of the advanced control methodology over a wide range of operating points and life cycle conditions. The on-board model is a piece-wise linear model derived from the nonlinear engine model and updated using an optimal tuner Kalman Filter estimation routine, which enables the on-board model to self-tune to account for engine performance variations. MBEC is used here to show how advanced control architectures can improve efficiency during the design phase of a turbofan engine by reducing conservative operability margins. The operability margins that can be reduced, such as stall margin, can expand the engine design space and offer potential for efficiency improvements. Application of MBEC architecture to a nonlinear engine simulation is shown to reduce the thrust specific fuel consumption by approximately 1% over the baseline design, while maintaining safe operation of the engine across the flight envelope.

  2. Advanced ISDN satellite designs and experiments

    NASA Technical Reports Server (NTRS)

    Pepin, Gerard R.

    1992-01-01

    The research performed by GTE Government Systems and the University of Colorado in support of the NASA Satellite Communications Applications Research (SCAR) Program is summarized. Two levels of research were undertaken. The first dealt with providing interim services Integrated Services Digital Network (ISDN) satellite (ISIS) capabilities that accented basic rate ISDN with a ground control similar to that of the Advanced Communications Technology Satellite (ACTS). The ISIS Network Model development represents satellite systems like the ACTS orbiting switch. The ultimate aim is to move these ACTS ground control functions on-board the next generation of ISDN communications satellite to provide full-service ISDN satellite (FSIS) capabilities. The technical and operational parameters for the advanced ISDN communications satellite design are obtainable from the simulation of ISIS and FSIS engineering software models of the major subsystems of the ISDN communications satellite architecture. Discrete event simulation experiments would generate data for analysis against NASA SCAR performance measure and the data obtained from the ISDN satellite terminal adapter hardware (ISTA) experiments, also developed in the program. The Basic and Option 1 phases of the program are also described and include the following: literature search, traffic mode, network model, scenario specifications, performance measures definitions, hardware experiment design, hardware experiment development, simulator design, and simulator development.

  3. Fluidized bed combustor modeling

    NASA Technical Reports Server (NTRS)

    Horio, M.; Rengarajan, P.; Krishnan, R.; Wen, C. Y.

    1977-01-01

    A general mathematical model for the prediction of performance of a fluidized bed coal combustor (FBC) is developed. The basic elements of the model consist of: (1) hydrodynamics of gas and solids in the combustor; (2) description of gas and solids contacting pattern; (3) kinetics of combustion; and (4) absorption of SO2 by limestone in the bed. The model is capable of calculating the combustion efficiency, axial bed temperature profile, carbon hold-up in the bed, oxygen and SO2 concentrations in the bubble and emulsion phases, sulfur retention efficiency and particulate carry over by elutriation. The effects of bed geometry, excess air, location of heat transfer coils in the bed, calcium to sulfur ratio in the feeds, etc. are examined. The calculated results are compared with experimental data. Agreement between the calculated results and the observed data are satisfactory in most cases. Recommendations to enhance the accuracy of prediction of the model are suggested.

  4. Numerical Prediction of Non-Reacting and Reacting Flow in a Model Gas Turbine Combustor

    NASA Technical Reports Server (NTRS)

    Davoudzadeh, Farhad; Liu, Nan-Suey

    2005-01-01

    The three-dimensional, viscous, turbulent, reacting and non-reacting flow characteristics of a model gas turbine combustor operating on air/methane are simulated via an unstructured and massively parallel Reynolds-Averaged Navier-Stokes (RANS) code. This serves to demonstrate the capabilities of the code for design and analysis of real combustor engines. The effects of some design features of combustors are examined. In addition, the computed results are validated against experimental data.

  5. Advanced tracking systems design and analysis

    NASA Technical Reports Server (NTRS)

    Potash, R.; Floyd, L.; Jacobsen, A.; Cunningham, K.; Kapoor, A.; Kwadrat, C.; Radel, J.; Mccarthy, J.

    1989-01-01

    The results of an assessment of several types of high-accuracy tracking systems proposed to track the spacecraft in the National Aeronautics and Space Administration (NASA) Advanced Tracking and Data Relay Satellite System (ATDRSS) are summarized. Tracking systems based on the use of interferometry and ranging are investigated. For each system, the top-level system design and operations concept are provided. A comparative system assessment is presented in terms of orbit determination performance, ATDRSS impacts, life-cycle cost, and technological risk.

  6. ASDA - Advanced Suit Design Analyzer computer program

    NASA Technical Reports Server (NTRS)

    Bue, Grant C.; Conger, Bruce C.; Iovine, John V.; Chang, Chi-Min

    1992-01-01

    An ASDA model developed to evaluate the heat and mass transfer characteristics of advanced pressurized suit design concepts for low pressure or vacuum planetary applications is presented. The model is based on a generalized 3-layer suit that uses the Systems Integrated Numerical Differencing Analyzer '85 in conjunction with a 41-node FORTRAN routine. The latter simulates the transient heat transfer and respiratory processes of a human body in a suited environment. The user options for the suit encompass a liquid cooled garment, a removable jacket, a CO2/H2O permeable layer, and a phase change layer.

  7. Advanced Avionics Breadboard Executive Design and Implementation

    NASA Technical Reports Server (NTRS)

    Adams, L. R.

    1972-01-01

    The advanced avionics breadboard (AAB) executive evolved from an effort to design and develop an avionics system. This executive is unique in that it supervises a triple redundant avionics computer system. Three IBM System 4 Pi/CP computers, operating synchronously and executing identical software, comprise the central processors which route data to and from a data bus via an input/output controller. The executive's basic function is to provide application programs with an efficient software structure within which to perform specific avionics application tasks. Although implemented in a triplex data management system, the AAB executive contains the flexibility to be adapted to other systems with minimal change.

  8. Advanced surface design for logistics analysis

    NASA Astrophysics Data System (ADS)

    Brown, Tim R.; Hansen, Scott D.

    The development of anthropometric arm/hand and tool models and their manipulation in a large system model for maintenance simulation are discussed. The use of Advanced Surface Design and s-fig technology in anthropometrics, and three-dimensional graphics simulation tools, are found to achieve a good balance between model manipulation speed and model accuracy. The present second generation models are shown to be twice as fast to manipulate as the first generation b-surf models, to be easier to manipulate into various configurations, and to more closely approximate human contours.

  9. Investigation of a low NOx full-scale annular combustor

    NASA Technical Reports Server (NTRS)

    1982-01-01

    An atmospheric test program was conducted to evaluate a low NOx annular combustor concept suitable for a supersonic, high-altitude aircraft application. The lean premixed combustor, known as the vortex air blast (VAB) concept, was tested as a 22.0-cm diameter model in the early development phases to arrive at basic design and performance criteria. Final demonstration testing was carried out on a full scale combustor of 0.66-m diameter. Variable geometry dilution ports were incorporated to allow operation of the combustor across the range of conditions between idle (T(in) = 422 K, T(out) = 917 K) and cruise (T(in) = 833 K, T(out) - 1778 K). Test results show that the design could meet the program NOx goal of 1.0 g NO2/kg fuel at a one-atmospheric simulated cruise condition.

  10. Combustor materials requirements and status of ceramic matrix composites

    NASA Technical Reports Server (NTRS)

    Hecht, Ralph J.; Johnson, Andrew M.

    1992-01-01

    The HSCT combustor will be required to operate with either extremely rich or lean fuel/air ratios to reduce NO(x) emission. NASA High Speed Research (HSR) sponsored programs at Pratt & Whitney (P&W) and GE Aircraft Engines (GEAE) have been studying rich and lean burn combustor design approaches which are capable of achieving the aggressive HSCT NO(x) emission goals. In both of the combustor design approaches under study, high temperature (2400-3000 F) materials are necessary to meet the HSCT emission goals of 3-8 gm/kg. Currently available materials will not meet the projected requirements for the HSCT combustor. The development of new materials is an enabling technology for the successful introduction to service of the HSCT.

  11. Gas turbine topping combustor

    DOEpatents

    Beer, J.; Dowdy, T.E.; Bachovchin, D.M.

    1997-06-10

    A combustor is described for burning a mixture of fuel and air in a rich combustion zone, in which the fuel bound nitrogen in converted to molecular nitrogen. The fuel rich combustion is followed by lean combustion. The products of combustion from the lean combustion are rapidly quenched so as to convert the fuel bound nitrogen to molecular nitrogen without forming NOx. The combustor has an air radial swirler that directs the air radially inward while swirling it in the circumferential direction and a radial fuel swirler that directs the fuel radially outward while swirling it in the same circumferential direction, thereby promoting vigorous mixing of the fuel and air. The air inlet has a variable flow area that is responsive to variations in the heating value of the fuel, which may be a coal-derived fuel gas. A diverging passage in the combustor in front of a bluff body causes the fuel/air mixture to recirculate with the rich combustion zone. 14 figs.

  12. Ceramic combustor mounting

    DOEpatents

    Hoffman, Melvin G.; Janneck, Frank W.

    1982-01-01

    A combustor for a gas turbine engine includes a metal engine block including a wall portion defining a housing for a combustor having ceramic liner components. A ceramic outlet duct is supported by a compliant seal on the metal block and a reaction chamber liner is stacked thereon and partly closed at one end by a ceramic bypass swirl plate which is spring loaded by a plurality of circumferentially spaced, spring loaded guide rods and wherein each of the guide rods has one end thereof directed exteriorly of a metal cover plate on the engine block to react against externally located biasing springs cooled by ambient air and wherein the rod spring support arrangement maintains the stacked ceramic components together so that a normal force is maintained on the seal between the outlet duct and the engine block under all operating conditions. The support arrangement also is operative to accommodate a substantial difference in thermal expansion between the ceramic liner components of the combustor and the metal material of the engine block.

  13. Computational Analysis of Dynamic SPK(S8)-JP8 Fueled Combustor-Sector Performance

    NASA Technical Reports Server (NTRS)

    Ryder, R.; Hendricks, Roberts C.; Huber, M. L.; Shouse, D. T.

    2010-01-01

    Civil and military flight tests using blends of synthetic and biomass fueling with jet fuel up to 50:50 are currently considered as "drop-in" fuels. They are fully compatible with aircraft performance, emissions and fueling systems, yet the design and operations of such fueling systems and combustors must be capable of running fuels from a range of feedstock sources. This paper provides Smart Combustor or Fuel Flexible Combustor designers with computational tools, preliminary performance, emissions and particulates combustor sector data. The baseline fuel is kerosene-JP-8+100 (military) or Jet A (civil). Results for synthetic paraffinic kerosene (SPK) fuel blends show little change with respect to baseline performance, yet do show lower emissions. The evolution of a validated combustor design procedure is fundamental to the development of dynamic fueling of combustor systems for gas turbine engines that comply with multiple feedstock sources satisfying both new and legacy systems.

  14. Advancing the State-of-the-Practice for Liquid Rocket Engine Injector Design

    NASA Technical Reports Server (NTRS)

    Tucker, P. K.; Kenny, R. J.; Richardson, B. R.; Anderso, W. E.; Austin, B. J.; Schumaker, S. A.; Muss, J. A.

    2015-01-01

    Current shortcomings in both the overall injector design process and its underlying combustion stability assessment methodology are rooted in the use of empirically based or low fidelity representations of complex physical phenomena and geometry details that have first order effects on performance, thermal environments and combustion stability. The result is a design and analysis capability that is often inadequate to reliably arrive at a suitable injector design in an efficient manner. Specifically, combustion instability has been particularly difficult to predict and mitigate. Large hydrocarbon-fueled booster engines have been especially problematic in this regard. Where combustion instability has been a problem, costly and time-consuming redesign efforts have often been an unfortunate consequence. This paper presents an overview of a recently completed effort at NASA Marshall Space Flight Center to advance the state-of-the-practice for liquid rocket engine injector design. Multiple perturbations of a gas-centered swirl coaxial (GCSC) element that burned gaseous oxygen and RP-1 were designed, assessed for combustion stability, and tested. Three designs, one stable, one marginally unstable and one unstable, were used to demonstrate both an enhanced overall injector design process and an improved combustion stability assessment process. High-fidelity results from state-of-the-art computational fluid dynamics CFD simulations were used to substantially augment and improve the injector design methodology. The CFD results were used to inform and guide the overall injector design process. They were also used to upgrade selected empirical or low-dimensional quantities in the ROCket Combustor Interactive Design (ROCCID) stability assessment tool. Hot fire single element injector testing was used to verify both the overall injector designs and the stability assessments. Testing was conducted at the Air Force Research Laboratory and at Purdue University. Companion papers

  15. NASA/USRA University advanced design program

    NASA Technical Reports Server (NTRS)

    Lembeck, Michael F.; Prussing, John

    1989-01-01

    The participation of the University of Illinois at Urbana-Champaign in the NASA/USRA University Advanced Design Program for the 1988 to 1989 academic year is reviewed. The University's design project was the Logistics Resupply and Emergency Crew Return System for Space Station Freedom. Sixty-one students divided into eight groups, participated in the spring 1989 semester. A presentation prepared by three students and a graduate teaching assistant for the program's summer conference summarized the project results. Teamed with the NASA Marshall Space Flight Center (MSFC), the University received support in the form of remote telecon lectures, reference material, and previously acquired applications software. In addition, a graduate teaching assistant was awarded a summer 1989 internship at MSFC.

  16. Disposable Diaper Absorbency: Improvements via Advanced Designs.

    PubMed

    Helmes, C Tucker; O'Connor, Robert; Sawyer, Larry; Young, Sharon

    2014-08-01

    Absorbency effectiveness in diapers has improved significantly in recent years with the advent of new ingredient combinations and advanced design features. With these features, many leading products maintain their dryness performance overnight. Considering the importance of holding liquid away from the skin, ongoing research in diaper construction focuses on strategies to increase the effectiveness to capture liquid and help avoid rewetting of infant skin. The layout and design of a disposable diaper allows for distribution of absorbency features where they can provide the optimal benefit. Clinical evidence indicates materials can keep moisture away from the skin in the diapered area, helping maintain proper skin hydration, minimizing irritation, and contributing to reduced rates of diaper rash.

  17. Analysis of Flow Migration in an Ultra-Compact Combustor

    DTIC Science & Technology

    2011-03-01

    into the high- pressure tur- bine rotor while presenting a uniform temperature across the turbine blades. Several numerical parameter studies have been... pressure losses through the combustor section. As a result of these investigations a 0.75m diameter UCC combustor design has been developed along with a...hybrid turning vane which replaces the last compressor vane and high- pressure turbine vane. Furthermore, the issue of cooling the hybrid vane in the

  18. Measuring Advances in HVAC Distribution System Design

    SciTech Connect

    Franconi, E.

    1998-05-01

    Substantial commercial building energy savings have been achieved by improving the performance of the HV AC distribution system. The energy savings result from distribution system design improvements, advanced control capabilities, and use of variable-speed motors. Yet, much of the commercial building stock remains equipped with inefficient systems. Contributing to this is the absence of a definition for distribution system efficiency as well as the analysis methods for quantifying performance. This research investigates the application of performance indices to assess design advancements in commercial building thermal distribution systems. The index definitions are based on a first and second law of thermodynamics analysis of the system. The second law or availability analysis enables the determination of the true efficiency of the system. Availability analysis is a convenient way to make system efficiency comparisons since performance is evaluated relative to an ideal process. A TRNSYS simulation model is developed to analyze the performance of two distribution system types, a constant air volume system and a variable air volume system, that serve one floor of a large office building. Performance indices are calculated using the simulation results to compare the performance of the two systems types in several locations. Changes in index values are compared to changes in plant energy, costs, and carbon emissions to explore the ability of the indices to estimate these quantities.

  19. Advanced Neutron Source radiological design criteria

    SciTech Connect

    Westbrook, J.L.

    1995-08-01

    The operation of the proposed Advanced Neutron Source (ANS) facility will present a variety of radiological protection problems. Because it is desired to design and operate the ANS according to the applicable licensing standards of the Nuclear Regulatory Commission (NRC), it must be demonstrated that the ANS radiological design basis is consistent not only with state and Department of Energy (DOE) and other usual federal regulations, but also, so far as is practicable, with NRC regulations and with recommendations of such organizations as the Institute of Nuclear Power Operations (INPO) and the Electric Power Research Institute (EPRI). Also, the ANS radiological design basis is in general to be consistent with the recommendations of authoritative professional and scientific organizations, specifically the National Council on Radiation Protection and Measurements (NCRP) and the International Commission on Radiological Protection (ICRP). As regards radiological protection, the principal goals of DOE regulations and guidance are to keep occupational doses ALARA [as low as (is) reasonably achievable], given the current state of technology, costs, and operations requirements; to control and monitor contained and released radioactivity during normal operation to keep public doses and releases to the environment ALARA; and to limit doses to workers and the public during accident conditions. Meeting these general design objectives requires that principles of dose reduction and of radioactivity control by employed in the design, operation, modification, and decommissioning of the ANS. The purpose of this document is to provide basic radiological criteria for incorporating these principles into the design of the ANS. Operations, modification, and decommissioning will be covered only as they are affected by design.

  20. Advanced burner test reactor preconceptual design report.

    SciTech Connect

    Chang, Y. I.; Finck, P. J.; Grandy, C.; Cahalan, J.; Deitrich, L.; Dunn, F.; Fallin, D.; Farmer, M.; Fanning, T.; Kim, T.; Krajtl, L.; Lomperski, S.; Moisseytsev, A.; Momozaki, Y.; Sienicki, J.; Park, Y.; Tang, Y.; Reed, C.; Tzanos, C; Wiedmeyer, S.; Yang, W.; Chikazawa, Y.; JAEA

    2008-12-16

    advanced fuel cycle; (2) To qualify the transuranics-containing fuels and advanced structural materials needed for a full-scale ABR; and (3) To support the research, development and demonstration required for certification of an ABR standard design by the U.S. Nuclear Regulatory Commission. The ABTR should also address the following additional objectives: (1) To incorporate and demonstrate innovative design concepts and features that may lead to significant improvements in cost, safety, efficiency, reliability, or other favorable characteristics that could promote public acceptance and future private sector investment in ABRs; (2) To demonstrate improved technologies for safeguards and security; and (3) To support development of the U.S. infrastructure for design, fabrication and construction, testing and deployment of systems, structures and components for the ABRs. Based on these objectives, a pre-conceptual design of a 250 MWt ABTR has been developed; it is documented in this report. In addition to meeting the primary and additional objectives listed above, the lessons learned from fast reactor programs in the U.S. and worldwide and the operating experience of more than a dozen fast reactors around the world, in particular the Experimental Breeder Reactor-II have been incorporated into the design of the ABTR to the extent possible.

  1. Recent advances in coupled laser cavity design

    NASA Astrophysics Data System (ADS)

    Leger, James R.; Chiang, Hung-Sheng; Nilsson, Johan; Ji, Junhau; Sahu, Jayanta

    2013-03-01

    External cavity coherent beam combining represents a path forward to higher fiber laser radiance, with several groups demonstrating scalable approaches. In this paper, we review recent advances in coupled laser cavity design. In particular, we compare various designs and describe the pros and cons of each with regard to sensitivity to path length errors. Experimental measurements using a specially designed dual-core fiber demonstrate the modal loss from a superposition architecture. A second area of investigation is concerned with Q-switch suppression in coupled laser cavities. The increased cavity loss that accompanies path length errors in the laser arms can suppress lasing, causing an energy build-up in the laser inversion. When the path length errors are removed and the cavity resumes its low loss state, the stored energy can be released in a manner analogous to Q-switching, creating a giant laser pulse. Since the peak power of this pulse can be many orders of magnitude larger than the cw power, the high instantaneous intensity can cause irreparable damage to optical components. We investigate passive systems that are designed to suppress this unwanted Q-switching by allowing alternative lasing paths to clamp the gain.

  2. Advanced photovoltaic solar array - Design and performance

    NASA Technical Reports Server (NTRS)

    Kurland, Richard; Stella, Paul

    1992-01-01

    This paper reports on the development of an ultralightweight flexible blanket, flatpack, foldout solar array design that can provide 3- to 4-fold improvement on specific power performance of current rigid panel arrays and a factor of two improvement over a first-generation flexible blanket array developed as a forerunner to the Space Station Freedom array. To date a prototype wing has been built with a projected specific power performance of about 138 W/kg at beginning-of-life (BOL) and 93 W/kg end-of-life (EOL) at 12 kW (BOL) for a 10-year geosynchronous (GEO) mission. The prototype wing hardware has been subjected to a series of system-level tests to demonstrate design feasibility. The design of the array is summarized. The major trade studies that led to the selection of the baseline design are discussed. Key system-level and component-level testing are described. Array-level performance projections are presented as a function of existing and advanced solar array component technology for various mission applications.

  3. Advanced Neutron Sources: Plant Design Requirements

    SciTech Connect

    Not Available

    1990-07-01

    The Advanced Neutron Source (ANS) is a new, world class facility for research using hot, thermal, cold, and ultra-cold neutrons. At the heart of the facility is a 350-MW{sub th}, heavy water cooled and moderated reactor. The reactor is housed in a central reactor building, with supporting equipment located in an adjoining reactor support building. An array of cold neutron guides fans out into a large guide hall, housing about 30 neutron research stations. Office, laboratory, and shop facilities are included to provide a complete users facility. The ANS is scheduled to begin operation at the Oak Ridge National Laboratory at the end of the decade. This Plant Design Requirements document defines the plant-level requirements for the design, construction, and operation of the ANS. This document also defines and provides input to the individual System Design Description (SDD) documents. Together, this Plant Design Requirements document and the set of SDD documents will define and control the baseline configuration of the ANS.

  4. Preliminary design studies of an advanced general aviation aircraft

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Preliminary design studies are presented for an advanced general aviation aircraft. Advanced guidance and display concepts, laminar flow, smart structures, fuselage and wing structural design and manufacturing, and preliminary configuration design are discussed. This project was conducted as a graduate level design class under the auspices of the KU/NASA/USRA Advanced Design Program in Aeronautics. The results obtained during the fall semester of 1990 (Phase 1) and the spring semester of 1991 (Phase 2) are presented.

  5. Analytical evaluation of the impact of broad specification fuels on high bypass turbofan engine combustors

    NASA Technical Reports Server (NTRS)

    Lohmann, R. P.; Szetela, E. J.; Vranos, A.

    1978-01-01

    The impact of the use of broad specification fuels on the design, performance durability, emissions and operational characteristics of combustors for commercial aircraft gas turbine engines was assessed. Single stage, vorbix and lean premixed prevaporized combustors, in the JT9D and an advanced energy efficient engine cycle were evaluated when operating on Jet A and ERBS (Experimental Referee Broad Specification) fuels. Design modifications, based on criteria evolved from a literature survey, were introduced and their effectiveness at offsetting projected deficiencies resulting from the use of ERBS was estimated. The results indicate that the use of a broad specification fuel such as ERBS, will necessitate significant technology improvements and redesign if deteriorated performance, durability and emissions are to be avoided. Higher radiant heat loads are projected to seriously compromise liner life while the reduced thermal stability of ERBS will require revisions to the engine-airframe fuel system to reduce the thermal stress on the fuel. Smoke and emissions output are projected to increase with the use of broad specification fuels. While the basic geometry of the single stage and vorbix combustors are compatible with the use of ERBS, extensive redesign of the front end of the lean premixed prevaporized burner will be required to achieve satisfactory operation and optimum emissions.

  6. Computational and design methods for advanced imaging

    NASA Astrophysics Data System (ADS)

    Birch, Gabriel C.

    This dissertation merges the optical design and computational aspects of imaging systems to create novel devices that solve engineering problems in optical science and attempts to expand the solution space available to the optical designer. This dissertation is divided into two parts: the first discusses a new active illumination depth sensing modality, while the second part discusses a passive illumination system called plenoptic, or lightfield, imaging. The new depth sensing modality introduced in part one is called depth through controlled aberration. This technique illuminates a target with a known, aberrated projected pattern and takes an image using a traditional, unmodified imaging system. Knowing how the added aberration in the projected pattern changes as a function of depth, we are able to quantitatively determine depth of a series of points from the camera. A major advantage this method permits is the ability for illumination and imaging axes to be coincident. Plenoptic cameras capture both spatial and angular data simultaneously. This dissertation present a new set of parameters that permit the design and comparison of plenoptic devices outside the traditionally published plenoptic 1.0 and plenoptic 2.0 configurations. Additionally, a series of engineering advancements are presented, including full system raytraces of raw plenoptic images, Zernike compression techniques of raw image files, and non-uniform lenslet arrays to compensate for plenoptic system aberrations. Finally, a new snapshot imaging spectrometer is proposed based off the plenoptic configuration.

  7. Advanced Turbine System (ATS) program conceptual design and product development. Quarterly report, March 1, 1994--May 31, 1994

    SciTech Connect

    1998-12-31

    GE has achieved a leadership position in the worldwide gas turbine industry in both industrial/utility markets and in aircraft engines. This design and manufacturing base plus their close contact with the users provides the technology for creation of the next generation advanced power generation systems for both the industrial and utility industries. GE has been active in the definition of advanced turbine systems for several years. These systems will leverage the technology from the latest developments in the entire GE gas turbine product line. These products will be USA based in engineering and manufacturing and are marketed through the GE Industrial and Power Systems. Achieving the advanced turbine system goals of 60% efficiency, 8 ppmvd NO{sub x} and 10% electric power cost reduction imposes competing characteristics on the gas turbine system. Two basic technical issues arise from this. The turbine inlet temperature of the gas turbine must increase to achieve both efficiency and cost goals. However, higher temperatures move in the direction of increased NO{sub x} emission. Improved coating and materials technologies along with creative combustor design can result in solutions to achieve the ultimate goal. GE`s view of the market, in conjunction with the industrial and utility objectives requires the development of Advanced Gas Turbine Systems which encompasses two potential products: a new aeroderivative combined cycle system for the industrial market and a combined cycle system for the utility sector that is based on an advanced frame machine.

  8. Advanced Turbine System (ATS) program conceptual design and product development. Quarterly report, September, 1--November 30, 1995

    SciTech Connect

    1997-06-01

    GE has achieved a leadership position in the worldwide gas turbine industry in both industrial/utility markets and in aircraft engines. This design and manufacturing base plus our close contact with the users provides the technology for creation of the next generation advanced power generation systems for both the industrial and utility industries. GE has been active in the definition of advanced turbine systems for several years. These systems will leverage the technology from the latest developments in the entire GE gas turbine product line. These products will be USA-based in engineering and manufacturing and are marketed through GE Power Systems. Achieving the Advanced Turbine Systems (ATS) goals of 60% efficiency, single-digit NOx, and 10% electric power cost reduction imposes competing characteristics on the gas turbine system. Two basic technical issues arise from this. The turbine inlet temperature of the gas turbine must increase to achieve both the efficiency and cost goals. However, higher temperatures move in the direction of increased NOx emissions. Improved coatings and other materials technologies along with creative combustor design can result in solutions which will achieve the ultimate goal. GE`s view of the market, in conjunction with the industrial and utility objectives, requires the development of Advanced Gas Turbine Systems which encompass two potential products: a new aeroderivative combined-cycle system for the industrial market, and a combined-cycle system for the utility sector that is based on an advanced frame machine.

  9. CFD Analysis of Emissions for a Candidate N+3 Combustor

    NASA Technical Reports Server (NTRS)

    Ajmani, Kumud

    2015-01-01

    An effort was undertaken to analyze the performance of a model Lean-Direct Injection (LDI) combustor designed to meet emissions and performance goals for NASA's N+3 program. Computational predictions of Emissions Index (EINOx) and combustor exit temperature were obtained for operation at typical power conditions expected of a small-core, high pressure-ratio (greater than 50), high T3 inlet temperature (greater than 950K) N+3 combustor. Reacting-flow computations were performed with the National Combustion Code (NCC) for a model N+3 LDI combustor, which consisted of a nine-element LDI flame-tube derived from a previous generation (N+2) thirteen-element LDI design. A consistent approach to mesh-optimization, spray-modeling and kinetics-modeling was used, in order to leverage the lessons learned from previous N+2 flame-tube analysis with the NCC. The NCC predictions for the current, non-optimized N+3 combustor operating indicated a 74% increase in NOx emissions as compared to that of the emissions-optimized, parent N+2 LDI combustor.

  10. CFD Analysis of Emissions for a Candidate N+3 Combustor

    NASA Technical Reports Server (NTRS)

    Ajmani, Kumud

    2015-01-01

    An effort was undertaken to analyze the performance of a model Lean-Direct Injection (LDI) combustor designed to meet emissions and performance goals for NASA's N+3 program. Computational predictions of Emissions Index (EINOx) and combustor exit temperature were obtained for operation at typical power conditions expected of a small-core, high pressure-ratio (greater than 50), high T3 inlet temperature (greater than 950K) N+3 combustor. Reacting-flow computations were performed with the National Combustion Code (NCC) for a model N+3 LDI combustor, which consisted of a nine-element LDI flame-tube derived from a previous generation (N+2) thirteen-element LDI design. A consistent approach to mesh-optimization, spraymodeling and kinetics-modeling was used, in order to leverage the lessons learned from previous N+2 flame-tube analysis with the NCC. The NCC predictions for the current, non-optimized N+3 combustor operating indicated a 74% increase in NOx emissions as compared to that of the emissions-optimized, parent N+2 LDI combustor.

  11. Quiet Clean Short-haul Experimental Engine (QCSEE) clean combustor test report

    NASA Technical Reports Server (NTRS)

    1975-01-01

    A component pressure test was conducted on a F101 PFRT combustor to evaluate the emissions levels of this combustor design at selected under the wing and over the wing operating conditions for the quiet clean short haul experimental engine (QCSEE). Emissions reduction techniques were evaluated which included compressor discharge bleed and sector burning in the combustor. The results of this test were utilized to compare the expected QCSEE emissions levels with the emission goals of the QCSEE engine program.

  12. HYPULSE combustor analysis

    NASA Technical Reports Server (NTRS)

    Rizkalla, O. F.

    1993-01-01

    The analysis of selected data from tests of unit fuel injectors in a generic scramjet combustor model is presented. The tests were conducted in the NASA HYPULSE expansion tube at conditions typical of flight at Mach 13.5 and 17. The analysis used a three-stream tube method, with finite-rate chemistry, in which the fuel, test gas, and mixing/combustive streams were treated independently but with the same static pressure. Performance of three candidate fuel injectors is examined based on deduced mixing and combustion efficiencies.

  13. Near-zero emissions combustor system for syngas and biofuels

    SciTech Connect

    Yongho, Kim; Rosocha, Louis

    2010-01-01

    research necessary to develop a novel, high-efficiency, low-emissions (near-zero, or as low as reasonably achievable), advanced combustion technology for electricity and heat production from biofuels and fuels derived from MSW. For any type of combustion technology, including the advanced technology of this project, two problems of special interest must be addressed: developing and optimizing the combustion chambers and the systems for igniting and sustaining the fuel-burning process. For MSW in particular, there are new challenges over gaseous or liquid fuels because solid fuels must be ground into fine particulates ({approx} 10 {micro}m diameter), fed into the advanced combustor, and combusted under plasma-assisted conditions that are quite different than gaseous or liquid fuels. The principal idea of the combustion chamber design is to use so-called reverse vortex gas flow, which allows efficient cooling of the chamber wall and flame stabilization in the central area of the combustor (Tornado chamber). Considerable progress has been made in design ing an advanced, reverse vortex flow combustion chamber for biofuels, although it was not tested on biofuels and a system that could be fully commercialized has never been completed.

  14. An Overview of Spray Modeling With OpenNCC and its Application to Emissions Predictions of a LDI Combustor at High Pressure

    NASA Technical Reports Server (NTRS)

    Raju, M. S.

    2016-01-01

    The open national combustion code (Open- NCC) is developed with the aim of advancing the current multi-dimensional computational tools used in the design of advanced technology combustors. In this paper we provide an overview of the spray module, LSPRAY-V, developed as a part of this effort. The spray solver is mainly designed to predict the flow, thermal, and transport properties of a rapidly evaporating multi-component liquid spray. The modeling approach is applicable over a wide-range of evaporating conditions (normal, superheat, and supercritical). The modeling approach is based on several well-established atomization, vaporization, and wall/droplet impingement models. It facilitates large-scale combustor computations through the use of massively parallel computers with the ability to perform the computations on either structured & unstructured grids. The spray module has a multi-liquid and multi-injector capability, and can be used in the calculation of both steady and unsteady computations. We conclude the paper by providing the results for a reacting spray generated by a single injector element with 600 axially swept swirler vanes. It is a configuration based on the next-generation lean-direct injection (LDI) combustor concept. The results include comparisons for both combustor exit temperature and EINOX at three different fuel/air ratios.

  15. Advanced Neutron Source: Plant Design Requirements

    SciTech Connect

    Not Available

    1990-07-01

    The Advanced Neutron Source will be a new world-class facility for research using hot, thermal, cold, and ultra-cold neutrons. The heart of the facility will be a 330-MW (fission), heavy-water cooled and heavy-water moderated reactor. The reactor will be housed in a central reactor building, with supporting equipment located in an adjoining reactor support building. An array of cold neutron guides will fan out into a large guide hall, housing about 30 neutron research stations. Appropriate office, laboratory, and shop facilities will be included to provide a complete facility for users. The ANS is scheduled to begin operation at the Oak Ridge National Laboratory early in the next decade. This PDR document defines the plant-level requirements for the design, construction, and operation of ANS. It also defines and provides input to the individual System Design Description (SDD) documents. Together, this PDR document and the set of SDD documents will define and control the baseline configuration of ANS.

  16. An Adaptive Instability Suppression Controls Method for Aircraft Gas Turbine Engine Combustors

    NASA Technical Reports Server (NTRS)

    Kopasakis, George; DeLaat, John C.; Chang, Clarence T.

    2008-01-01

    An adaptive controls method for instability suppression in gas turbine engine combustors has been developed and successfully tested with a realistic aircraft engine combustor rig. This testing was part of a program that demonstrated, for the first time, successful active combustor instability control in an aircraft gas turbine engine-like environment. The controls method is called Adaptive Sliding Phasor Averaged Control. Testing of the control method has been conducted in an experimental rig with different configurations designed to simulate combustors with instabilities of about 530 and 315 Hz. Results demonstrate the effectiveness of this method in suppressing combustor instabilities. In addition, a dramatic improvement in suppression of the instability was achieved by focusing control on the second harmonic of the instability. This is believed to be due to a phenomena discovered and reported earlier, the so called Intra-Harmonic Coupling. These results may have implications for future research in combustor instability control.

  17. NO{sub x} and CO emissions from an aerovalve pulse combustor

    SciTech Connect

    Norton, T.S.; Richards, G.A.; Casleton, K.H.; Jenkins, L.C.

    1993-12-31

    The Morgantown Energy Technology Center (METC) has an ongoing research program to investigate the benefits of pulse combustion in advanced energy systems. The overall goals are to study and improve the pressure-gain performance of pulse combustors, to investigate the effects of pressure on operating characteristics, and ultimately to determine the feasibility of using pulse combustors in gas turbine applications [Gemmen et al., 1992, 1993]. An additional goal is to ensure that the combustor designs under consideration produce low levels of NO{sub x} and CO pollutant emissions. The gas sampling and analysis system is currently under development. Preliminary data on NO{sub x} and CO emissions concentrations have been obtained and appear encouraging. After further leak checking, system debugging, and calibrating are completed, new experimental data should be available to be reported at the conference. In addition, a modeling effort is being initiated to aid in the interpretation of the experimental results. Some details of the experimental and modeling approaches are given below.

  18. Advances in fuel cell vehicle design

    NASA Astrophysics Data System (ADS)

    Bauman, Jennifer

    Factors such as global warming, dwindling fossil fuel reserves, and energy security concerns combine to indicate that a replacement for the internal combustion engine (ICE) vehicle is needed. Fuel cell vehicles have the potential to address the problems surrounding the ICE vehicle without imposing any significant restrictions on vehicle performance, driving range, or refuelling time. Though there are currently some obstacles to overcome before attaining the widespread commercialization of fuel cell vehicles, such as improvements in fuel cell and battery durability, development of a hydrogen infrastructure, and reduction of high costs, the fundamental concept of the fuel cell vehicle is strong: it is efficient, emits zero harmful emissions, and the hydrogen fuel can be produced from various renewable sources. Therefore, research on fuel cell vehicle design is imperative in order to improve vehicle performance and durability, increase efficiency, and reduce costs. This thesis makes a number of key contributions to the advancement of fuel cell vehicle design within two main research areas: powertrain design and DC/DC converters. With regards to powertrain design, this research first analyzes various powertrain topologies and energy storage system types. Then, a novel fuel cell-battery-ultracapacitor topology is presented which shows reduced mass and cost, and increased efficiency, over other promising topologies found in the literature. A detailed vehicle simulator is created in MATLAB/Simulink in order to simulate and compare the novel topology with other fuel cell vehicle powertrain options. A parametric study is performed to optimize each powertrain and general conclusions for optimal topologies, as well as component types and sizes, for fuel cell vehicles are presented. Next, an analytical method to optimize the novel battery-ultracapacitor energy storage system based on maximizing efficiency, and minimizing cost and mass, is developed. This method can be applied

  19. Reverse-flow combustor for small gas turbines with pressure-atomizing fuel injectors

    NASA Technical Reports Server (NTRS)

    Norgren, C. T.; Mularz, E. J.; Riddlebaugh, S. M.

    1978-01-01

    A reverse flow combustor suitable for a small gas turbine (2 to 3 kg/s mass flow) was used to evalute the effect of pressure atomizing fuel injectors on combustor performance. In these tests an experimental combustor was designed to operate with 18 simplex pressure atomizing fuel injectors at sea level takeoff conditions. To improve performance at low power conditions, fuel was redistributed so that only every other injector was operational. Combustor performance, emissions, and liner temperature were compared over a range of pressure and inlet air temperatures corresponding to simulated idle, cruise, and takeoff conditions typical of a 16 to 1 pressure ratio turbine engine.

  20. Staged cascade fluidized bed combustor

    DOEpatents

    Cannon, Joseph N.; De Lucia, David E.; Jackson, William M.; Porter, James H.

    1984-01-01

    A fluid bed combustor comprising a plurality of fluidized bed stages interconnected by downcomers providing controlled solids transfer from stage to stage. Each stage is formed from a number of heat transfer tubes carried by a multiapertured web which passes fluidizing air to upper stages. The combustor cross section is tapered inwardly from the middle towards the top and bottom ends. Sorbent materials, as well as non-volatile solid fuels, are added to the top stages of the combustor, and volatile solid fuels are added at an intermediate stage.

  1. Analytical fuel property effects: Small combustors, phase 2

    NASA Technical Reports Server (NTRS)

    Hill, T. G.; Monty, J. D.; Morton, H. L.

    1985-01-01

    The effects of non-standard aviation fuels on a typical small gas turbine combustor were studied and the effectiveness of design changes intended to counter the effects of these fuels was evaluated. The T700/CT7 turboprop engine family was chosen as being representative of the class of aircraft power plants desired for this study. Fuel properties, as specified by NASA, are characterized by low hydrogen content and high aromatics levels. No. 2 diesel fuel was also evaluated in this program. Results demonstrated the anticipated higher than normal smoke output and flame radiation intensity with resulting increased metal temperatures on the baseline T700 combustor. Three new designs were evaluated using the non standard fuels. The three designs incorporated enhanced cooling features and smoke reduction features. All three designs, when burning the broad specification fuels, exhibited metal temperatures at or below the baseline combustor temperatures on JP-5. Smoke levels were acceptable but higher than predicted.

  2. Non-Intrusive Laser-Induced Imaging for Speciation and Patternation in High Pressure Gas Turbine Combustors

    NASA Technical Reports Server (NTRS)

    Locke, Randy J.; Zaller, Michelle M.; Hicks, Yolanda R.; Anderson, Robert C.

    1999-01-01

    The next generation of was turbine combustors for aerospace applications will be required to meet increasingly stringent constraints on fuel efficiency, noise abatement, and emissions. The power plants being designed to meet these constraints will operate at extreme conditions of temperature and pressure, thereby generating unique challenges to the previously employed diagnostic methodologies. Current efforts at NASA Glenn Research Center (GRC) utilize optically accessible, high pressure flametubes and sector combustor rigs to probe, via advanced nonintrusive laser techniques, the complex flowfields encountered in advanced combustor designs. The fuel-air mixing process is of particular concern for lowering NO(x) emissions generated in lean, premixed engine concepts. Using planar laser-induced fluorescence (PLIF) we have obtained real-time, detailed imaging of the fuel spray distribution for a number of fuel injector over a wide range of operational conditions that closely match those expected in the proposed propulsion systems. Using a novel combination of planar imaging, of fuel fluorescence and computational analysis that allows an examination of the flowfield from any perspective, we have produced spatially and temporally resolved fuel-air distribution maps. These maps provide detailed insight into the fuel injection at actual conditions never before possible, thereby greatly enhancing the evaluation of fuel injector performance and combustion phenomena.

  3. Segmented annular combustor

    DOEpatents

    Reider, Samuel B.

    1979-01-01

    An industrial gas turbine engine includes an inclined annular combustor made up of a plurality of support segments each including inner and outer walls of trapezoidally configured planar configuration extents and including side flanges thereon interconnected by means of air cooled connector bolt assemblies to form a continuous annular combustion chamber therebetween and wherein an air fuel mixing chamber is formed at one end of the support segments including means for directing and mixing fuel within a plenum and a perforated header plate for directing streams of air and fuel mixture into the combustion chamber; each of the outer and inner walls of each of the support segments having a ribbed lattice with tracks slidably supporting porous laminated replaceable panels and including pores therein for distributing combustion air into the combustion chamber while cooling the inner surface of each of the panels by transpiration cooling thereof.

  4. Catalytic Combustor for Fuel-Flexible Turbine

    SciTech Connect

    W. R. Laster; E. Anoshkina

    2008-01-31

    Under the sponsorship of the U. S. Department of Energy's National Energy Technology Laboratory, Siemens Westinghouse has conducted a three-year program to develop an ultra low NOx, fuel flexible catalytic combustor for gas turbine application in IGCC. The program is defined in three phases: Phase 1 - Implementation Plan, Phase 2 - Validation Testing and Phase 3 - Field Testing. Both Phase 1 and Phase 2 of the program have been completed. In IGCC power plants, the gas turbine must be capable of operating on syngas as a primary fuel and an available back-up fuel such as natural gas. In this program the Rich Catalytic Lean (RCLTM) technology is being developed as an ultra low NOx combustor. In this concept, ultra low NOx is achieved by stabilizing a lean premix combustion process by using a catalytic reactor to oxidize a portion of the fuel, increasing the temperature of fuel/air mixture prior to the main combustion zone. In Phase 1, the feasibility of the catalytic concept for syngas application has been evaluated and the key technology issues identified. In Phase II the technology necessary for the application of the catalytic concept to IGCC fuels was developed through detailed design and subscale testing. Phase III (currently not funded) will consist of full-scale combustor basket testing on natural gas and syngas.

  5. Catalytic Combustor for Fuel-Flexible Turbine

    SciTech Connect

    Laster, W. R.; Anoshkina, E.

    2008-01-31

    Under the sponsorship of the U. S. Department of Energy’s National Energy Technology Laboratory, Siemens Westinghouse has conducted a three-year program to develop an ultra low NOx, fuel flexible catalytic combustor for gas turbine application in IGCC. The program is defined in three phases: Phase 1- Implementation Plan, Phase 2- Validation Testing and Phase 3 – Field Testing. Both Phase 1 and Phase 2 of the program have been completed. In IGCC power plants, the gas turbine must be capable of operating on syngas as a primary fuel and an available back-up fuel such as natural gas. In this program the Rich Catalytic Lean (RCLTM) technology is being developed as an ultra low NOx combustor. In this concept, ultra low NOx is achieved by stabilizing a lean premix combustion process by using a catalytic reactor to oxidize a portion of the fuel, increasing the temperature of fuel/air mixture prior to the main combustion zone. In Phase 1, the feasibility of the catalytic concept for syngas application has been evaluated and the key technology issues identified. In Phase II the technology necessary for the application of the catalytic concept to IGCC fuels was developed through detailed design and subscale testing. Phase III (currently not funded) will consist of full-scale combustor basket testing on natural gas and syngas.

  6. Advanced technology's impact on compressor design and development - A perspective

    NASA Technical Reports Server (NTRS)

    Ball, Calvin L.

    1989-01-01

    A historical perspective of the impact of advanced technologies on compression system design and development for aircraft gas turbine applications is presented. A bright view of the future is projected in which further advancements in compression system technologies will be made. These advancements will have a significant impact on the ability to meet the ever-more-demanding requirements being imposed on the propulsion system for advanced aircraft. Examples are presented of advanced compression system concepts now being studied. The status and potential impact of transitioning from an empirically derived design system to a computationally oriented system are highlighted. A current NASA Lewis Research Center program to enhance this transitioning is described.

  7. Advanced technologies impact on compressor design and development: A perspective

    NASA Technical Reports Server (NTRS)

    Ball, Calvin L.

    1989-01-01

    A historical perspective of the impact of advanced technologies on compression system design and development for aircraft gas turbine applications is presented. A bright view of the future is projected in which further advancements in compression system technologies will be made. These advancements will have a significant impact on the ability to meet the ever-more-demanding requirements being imposed on the propulsion system for advanced aircraft. Examples are presented of advanced compression system concepts now being studied. The status and potential impact of transitioning from an empirically derived design system to a computationally oriented system are highlighted. A current NASA Lewis Research Center program to enhance this transitioning is described.

  8. Core Noise: Overview of Upcoming LDI Combustor Test

    NASA Technical Reports Server (NTRS)

    Hultgren, Lennart S.

    2012-01-01

    This presentation is a technical summary of and outlook for NASA-internal and NASA-sponsored external research on core (combustor and turbine) noise funded by the Fundamental Aeronautics Program Fixed Wing Project. The presentation covers: the emerging importance of core noise due to turbofan design trends and its relevance to the NASA N+3 noise-reduction goal; the core noise components and the rationale for the current emphasis on combustor noise; and the current and planned research activities in the combustor-noise area. Two NASA-sponsored research programs, with particular emphasis on indirect combustor noise, "Acoustic Database for Core Noise Sources", Honeywell Aerospace (NNC11TA40T) and "Measurement and Modeling of Entropic Noise Sources in a Single-Stage Low-Pressure Turbine", U. Illinois/U. Notre Dame (NNX11AI74A) are briefly described. Recent progress in the development of CMC-based acoustic liners for broadband noise reduction suitable for turbofan-core application is outlined. Combustor-design trends and the potential impacts on combustor acoustics are discussed. A NASA GRC developed nine-point lean-direct-injection (LDI) fuel injector is briefly described. The modification of an upcoming thermo-acoustic instability evaluation of the GRC injector in a combustor rig to also provide acoustic information relevant to community noise is presented. The NASA Fundamental Aeronautics Program has the principal objective of overcoming today's national challenges in air transportation. The reduction of aircraft noise is critical to enabling the anticipated large increase in future air traffic. The Quiet Performance Research Theme of the Fixed Wing Project aims to develop concepts and technologies to dramatically reduce the perceived community noise attributable to aircraft with minimal impact on weight and performance.

  9. Design principles for advanced carburized bearing steels

    NASA Astrophysics Data System (ADS)

    Wright, James Anthony

    Rolling contact fatigue behavior of carburized C69-1 steel was measured and analyzed using an NTN rolling contact fatigue tester. Core precipitation of nanoscale 6 phase in C69-2 steel was measured with 1DAP microanalysis. Precipitation behavior in M50NiL-0.38C was examined using small angle neutron scattering, transmission electron microscopy, one-dimensional atom probe microanalysis, three-dimensional atom probe microanalysis, Vickers microhardness, and ThermoCalc thermodynamic modeling software. Five different carbide phases were tentatively identified as Fe3C, M2C, MC, M6C, and M 23C6. The hardness evolution was modeled with the measured microstructural data and scaled to measured microhardness. A multiphase precipitation model was developed to predict the volume fraction of each phase during tempering. Stress relaxation during tempering of M50NiL-0.38C was shown to be controlled by carbide precipitation kinetics using tensile and split-ring methods. From these experiments design principles for advanced carburized steels were deduced. Because of their role in fatigue nucleation, no primary carbides should be present after solution treatment. A single phase M2C precipitate dispersion should be over-aged to be slightly larger than its peak strength state to avoid cyclic shearing and improve rolling contact fatigue resistance. Other carbide phases can be avoided because they are less efficient strengtheners than the M2C phase. The embrittling sigma phase should be avoided in the low carbon core by reducing the driving force for precipitation. The steel should have some residual austenite in the carburized case after quenching from the solution treatment; this retained austenite should be completely transformed upon a cryogenic treatment after tempering to restore favorable, residual compressive stress in the case.

  10. Low NO/x/ heavy fuel combustor program

    NASA Technical Reports Server (NTRS)

    Lister, E.; Niedzwiecki, R. W.; Nichols, L.

    1980-01-01

    The paper deals with the 'Low NO/x/ Heavy Fuel Combustor Program'. Main program objectives are to generate and demonstrate the technology required to develop durable gas turbine combustors for utility and industrial applications, which are capable of sustained, environmentally acceptable operation with minimally processed petroleum residual fuels. The program will focus on 'dry' reductions of oxides of nitrogen (NO/x/), improved combustor durability and satisfactory combustion of minimally processed petroleum residual fuels. Other technology advancements sought include: fuel flexibility for operation with petroleum distillates, blends of petroleum distillates and residual fuels, and synfuels (fuel oils derived from coal or shale); acceptable exhaust emissions of carbon monoxide, unburned hydrocarbons, sulfur oxides and smoke; and retrofit capability to existing engines.

  11. Low NO(x) heavy fuel combustor program

    NASA Technical Reports Server (NTRS)

    Lister, E.; Niedzwiecki, R. W.; Nichols, L.

    1979-01-01

    The 'low nitrogen oxides heavy fuel combustor' program is described. Main program objectives are to generate and demonstrate the technology required to develop durable gas turbine combustors for utility and industrial applications, which are capable of sustained, environmentally acceptable operation with minimally processed petroleum residual fuels. The program will focus on 'dry' reductions of oxides of nitrogen, improved combustor durability, and satisfactory combustion of minimally processed petroleum residual fuels. Other technology advancements sought include: fuel flexibility for operation with petroleum distillates, blends of petroleum distillates and residual fuels, and synfuels (fuel oils derived from coal or shale); acceptable exhaust emissions of carbon monoxide, unburned hydrocarbons, sulfur oxides and smoke; and retrofit capability to existing engines.

  12. The pollution reduction technology program for can-annular combustor engines - Description and results

    NASA Technical Reports Server (NTRS)

    Roberts, R.; Fiorentino, A. J.; Diehl, L.

    1976-01-01

    Pollutant reduction and performance characteristics were determined for three successively more advanced combustor concepts. Program Element I consisted of minor modifications to the current production JT8D combustor and fuel system to evaluate means of improved fuel preparation and changes to the basic airflow distribution. Element II addressed versions of the two-staged Vorbix (vortex burning and mixing) combustor and represented a moderate increase in hardware complexity and difficulty of development. The concept selected for Element III employed vaporized fuel as a means of achieving minimum emission levels and represented the greatest difficulty of development and adaptation to the JT8D engine. Test results indicate that the Element I single-stage combustors were capable of dramatic improvement in idle pollutants. The multistage combustors evaluated in Program Elements II and III simultaneously reduced CO, THC and NOx emissions, but were unable to satisfy the current 1979 EPA standards.

  13. Thermal Analysis and Design of an Advanced Space Suit

    NASA Technical Reports Server (NTRS)

    Lin, Chin H.; Campbell, Anthony B.; French, Jonathan D.; French, D.; Nair, Satish S.; Miles, John B.

    2000-01-01

    The thermal dynamics and design of an Advanced Space Suit are considered. A transient model of the Advanced Space Suit has been developed and implemented using MATLAB/Simulink to help with sizing, with design evaluation, and with the development of an automatic thermal comfort control strategy. The model is described and the thermal characteristics of the Advanced Space suit are investigated including various parametric design studies. The steady state performance envelope for the Advanced Space Suit is defined in terms of the thermal environment and human metabolic rate and the transient response of the human-suit-MPLSS system is analyzed.

  14. Advanced Turbine Systems (ATS) program conceptual design and product development. Quarterly report, December 1, 1994--February 28, 1995

    SciTech Connect

    1995-12-31

    Achieving the advanced turbine system goals of 60% efficiency, 8 ppmvd NOx and 10% electric power cost reduction imposes competing characteristics on the gas turbine system. Two basic technical issues arise from this. The turbine inlet temperature of the gas turbine must increase to achieve both efficiency and cost goals. However, higher temperatures move in the direction of increased NOx emission. Improved costing and materials technologies along with creative combustor design can result in solutions to achieve the ultimate goal. The GE Advanced Gas Turbine Development program is focused on two specific products: (1) a 70 MW class industrial gas turbine based on the GE90 core technology utilizing an innovative air cooling methodology; (2) a 200 MW class utility gas turbine based on an advanced GE heavy duty machines utilizing advanced cooling and enhancement in component efficiency. Both of these activities require the identification and resolution of technical issues critical to achieving Advanced Turbine System (ATS) goals. The emphasis for the industrial ATS will be placed upon innovative cycle design and low emission combustion. The emphasis for the utility ATS will be placed upon innovative cycle design and low emission combustion. The emphasis for the utility ATS will be placed on developing a technology base for advanced turbine cooling while utilizing demonstrated and planned improvements in low emissions combustion. Significant overlap in the development programs will allow common technologies to be applied to both products. GE`s Industrial and Power Systems is solely responsible for offering Ge products for the industrial and utility markets. The GE ATS program will be managed fully by this organization with core engine technology being supplied by GE Aircraft Engines (GEAE) and fundamental studies supporting both product developments being conducted by GE Corporate Research and Development (CRD).

  15. Advanced Turbine Systems (ATS) program conceptual design and product development. Quarterly report, December 1, 1993--February 28, 1994

    SciTech Connect

    1997-06-01

    GE has achieved a leadership position in the worldwide gas turbine industry in both industrial/utility markets and in aircraft engines. This design and manufacturing base plus our close contact with the users provides the technology for creation of the next generation advanced power generation systems for both the industrial and utility industries. GE has been active in the definition of advanced turbine systems for several years. These systems will leverage the technology from the latest developments in the entire GE gas turbine product line. These products will be USA based in engineering and manufacturing and are marketed through the GE Industrial and Power Systems. Achieving the advanced turbine system goals of 60% efficiency, 8 ppmvd NOx and 10% electric power cost reduction imposes competing characteristics on the gas turbine system. Two basic technical issues arise from this. The turbine inlet temperature of the gas turbine must increase to achieve both efficiency and cost goals. However, higher temperatures move in the direction of increased NOx emission. Improved coating and materials technologies along with creative combustor design can result in solutions to achieve the ultimate goal.

  16. Advanced Turbine Systems (ATS) program conceptual design and product development. Quarterly report, August 25--November 30, 1993

    SciTech Connect

    1997-06-01

    GE has achieved a leadership position in the worldwide gas turbine industry in both industrial/utility markets and in aircraft engines. This design and manufacturing base plus our close contact with the users provides the technology for creation of the next generation advanced power generation systems for both the industrial and utility industries. GE has been active in the definition of advanced turbine systems for several years. These systems will leverage the technology from the latest developments in the entire GE gas turbine product line. These products will be USA based in engineering and manufacturing and are marketed through the GE Industrial and Power Systems. Achieving the advanced turbine system goals of 60% efficiency, 8 ppmvd NOx and 10% electric power cost reduction imposes competing characteristics on the gas turbine system. Two basic technical issues arise from this. The turbine inlet temperature of the gas turbine must increase to achieve both efficiency and cost goals. However, higher temperatures move in the direction of increased NOx emission. Improved coating and materials technologies along with creative combustor design can result in solutions to achieve the ultimate goal.

  17. The Advanced Light Source: Technical Design

    SciTech Connect

    Authors, Various

    1984-05-01

    The Advanced Light Source (ALS) is a synchrotron radiation source consisting of a 50-MeV linear accelerator, a 1.3-GeV 'booster' synchrotron, a 1.3-GeV electron storage ring, and a number of photon beam lines, as shown in Figure 1. As an introduction to a detailed description of the Advanced Light Source, this section provides brief discussions on the characteristics of synchrotron radiation and on the theory of storage rings. Appendix A contents: Introduction to Synchrotron-Radiation Sources; Storage Ring; Injection System; Control System; Insertion Devices; Photon Beam Lines; and References.

  18. Investigation on the flame dynamics of meso-combustors

    NASA Astrophysics Data System (ADS)

    Ahmed, Mahbub

    Miniature heat engines burning hydrogen and hydrocarbon fuels have significantly higher energy densities compared to conventional lithium batteries and thus will play an essential role in the portable production of power for future electronics, remote sensors, and micro aerial vehicles. Additionally, miniature heat engines will tremendously benefit next generation of environmental technologies such as steam reforming, ammonia decomposition and fuel cells. Successful miniaturization of heat engine components demand a more complete and broader understanding of micro-fluid dynamics and micro-combustion phenomena associated with the combustor design. This dissertation is aimed at investigating the details of the micro-mixing dynamics and the combustion behavior of the meso-combustor and to create fundamental understanding of physics based design methodology. The primary goals of the project are (i) to develop an understanding of fuel-air mixing inside a meso-combustor, (ii) to develop an understanding of the flame stability (flame quenching and velocity blowout) criteria of a meso-combustor, (iii) to understand the thermal behavior of the meso-combustor, and (iv) to correlate these with combustor operating conditions such as the Reynolds number, equivalent ratio, and thermal power etc. The present study shows that adequate mixing of fuel and air is achievable in millimeter scale combustors. Both computed results and experimental measurements of iso-thermal (non-burning) flows at different mixing configurations indicate that the laminar burning velocity remains higher than the local flow velocities in most of the combustor locations to support stable flame propagations. Stable flames of hydrogen are achieved for all mixing and flow configurations. The combustion of methane with air as oxidizer in the combustors is unreliable. However, highly stable combustion of methane at various mixing and flow conditions is achieved when pure oxygen is used as an oxidizer. The

  19. Two stage catalytic combustor

    NASA Technical Reports Server (NTRS)

    Alvin, Mary Anne (Inventor); Bachovchin, Dennis (Inventor); Smeltzer, Eugene E. (Inventor); Lippert, Thomas E. (Inventor); Bruck, Gerald J. (Inventor)

    2010-01-01

    A catalytic combustor (14) includes a first catalytic stage (30), a second catalytic stage (40), and an oxidation completion stage (49). The first catalytic stage receives an oxidizer (e.g., 20) and a fuel (26) and discharges a partially oxidized fuel/oxidizer mixture (36). The second catalytic stage receives the partially oxidized fuel/oxidizer mixture and further oxidizes the mixture. The second catalytic stage may include a passageway (47) for conducting a bypass portion (46) of the mixture past a catalyst (e.g., 41) disposed therein. The second catalytic stage may have an outlet temperature elevated sufficiently to complete oxidation of the mixture without using a separate ignition source. The oxidation completion stage is disposed downstream of the second catalytic stage and may recombine the bypass portion with a catalyst exposed portion (48) of the mixture and complete oxidation of the mixture. The second catalytic stage may also include a reticulated foam support (50), a honeycomb support, a tube support or a plate support.

  20. Combustor and method for distributing fuel in the combustor

    SciTech Connect

    Uhm, Jong Ho; Ziminsky, Willy Steve; Johnson, Thomas Edward; York, William David

    2016-04-26

    A combustor includes a tube bundle that extends radially across at least a portion of the combustor. The tube bundle includes an upstream surface axially separated from a downstream surface. A plurality of tubes extends from the upstream surface through the downstream surface, and each tube provides fluid communication through the tube bundle. A baffle extends axially inside the tube bundle between adjacent tubes. A method for distributing fuel in a combustor includes flowing a fuel into a fuel plenum defined at least in part by an upstream surface, a downstream surface, a shroud, and a plurality of tubes that extend from the upstream surface to the downstream surface. The method further includes impinging the fuel against a baffle that extends axially inside the fuel plenum between adjacent tubes.

  1. ADVANCED HOT SECTION MATERIALS AND COATINGS TEST RIG

    SciTech Connect

    Scott Reome; Dan Davies

    2004-04-30

    The Hyperbaric Advanced Hot Section Materials & Coating Test Rig program provides design and implementation of a laboratory rig capable of simulating the hot gas path conditions of coal-gas fired industrial gas turbine engines. The principal activity during this reporting period were the evaluation of syngas combustor concepts, the evaluation of test section concepts and the selection of the preferred rig configuration.

  2. Development of a new method for improving load turndown in fluidized bed combustors: Final report

    SciTech Connect

    Brown, R.C.

    1988-12-01

    The objective of this research was to investigate a new concept in fluidized bed design that improves load turndown capability. This improvement is accomplished by independently controlling heat transfer and combustion in the combustor. The design consists of two fluidized beds, one central and one annular. The central bed serves as the combustion bed. The annular bed is fluidized separately from the combustion bed and its level of fluidization determine the overall heat transfer rate from the combustion bed to the surrounding water jacket. Early theoretical considerations suggested a load turndown exceeding ten was possible for this design. This research consisted of three major phases: development of a computational model to predict heat transfer in the two-bed combustor, heat transfer measurements in hot-and-cold flow models of the combustor, and combustion tests in an optimally designed combustor. The computation model was useful in selecting the design of the combustor. Annular bed width and particle sizes were chosen with the aid of the model. The heat transfer tests were performed to determine if the existing correlations for fluidized bed heat transfer coefficients were sufficiently accurate for high aspect ratio fluidized beds (such as the annular bed in the combustor). Combustion tests were performed in an optimally designed combustor. Three fuel forms were used: double screened, crushed coal, coal-water-limestone mixtures (CWLM), and coal-limestone briquettes. 18 refs., 30 figs., 8 tabs.

  3. Flame structures in the pressurized methane-air combustor

    SciTech Connect

    Yamamoto, Tsuyoshi; Miyazaki, Tomonaga, Furuhata, Tomohiko; Arai, Norio

    1998-07-01

    This study has been carried out in order to investigate the applicability of a pressurized and fuel-rich burner at a first stage combustor for a newly proposed chemical gas turbine system. The flammability limits, exhaust gas composition and the NO{sub x} emission characteristics under the pressurized conditions of 1.1--4.1 MPa have been investigated in a model combustor. This paper focuses on the influence of pressure and F/A equivalence ratio on flame structures of pressurized combustion with methane and air to obtain detailed data for designing of fuel-rich combustor for gas turbine application. The flame under fuel-rich condition and pressure of 1 MPa showed underventilated structure like other atmospheric fuel-rich flames while the flame under pressure over 1.5 MPa had shapes as fuel-lean flame. The flame becomes longer as the pressure was increased under the fuel-lean conditions, which under fuel-rich condition the influence of pressure on flame length was smaller in comparison with the flame under fuel-lean conditions. These results give an opportunity for developing smaller combustor under fuel-rich and pressurized condition compared to fuel-lean one. Numerical simulation has been done for defining the temperature profile in the model combustor using the k-{var{underscore}epsilon} turbulence model and three-step reaction model. The comparison between theoretical results and experimental data showed fair agreements.

  4. Testing and Characterization of CMC Combustor Liners

    NASA Technical Reports Server (NTRS)

    Robinson, R. Craig; Verrilli, Michael J.

    2003-01-01

    Multiple combustor liner applications, both segmented and fully annular designs, have been configured for exposure in NASA's High Pressure Burner Rig (HPBR). The segmented liners were attached to the rig structure with SiC/SiC fasteners and exposed to simulated gas turbine conditions for nearly 200 hours. Test conditions included pressures of 6 atm., gas velocity of 42 m/s, and gas temperatures near 1450 C. The temperatures of both the cooled and combustion flow sides of the liners were measured using optical and contact measurement techniques. Minor weight loss was observed, but the liners remained structural sound, although damage was noted in some fasteners.

  5. Radial midframe baffle for can-annular combustor arrangement having tangentially oriented combustor cans

    SciTech Connect

    Rodriguez, Jose L.

    2015-09-15

    A can-annular gas turbine engine combustion arrangement (10), including: a combustor can (12) comprising a combustor inlet (38) and a combustor outlet circumferentially and axially offset from the combustor inlet; an outer casing (24) defining a plenum (22) in which the combustor can is disposed; and baffles (70) configured to divide the plenum into radial sectors (72) and configured to inhibit circumferential motion of compressed air (16) within the plenum.

  6. Scaling of Performance in Liquid Propellant Rocket Engine Combustors

    NASA Technical Reports Server (NTRS)

    Hulka, James R.

    2007-01-01

    This paper discusses scaling of combustion and combustion performance in liquid propellant rocket engine combustion devices. In development of new combustors, comparisons are often made between predicted performance in a new combustor and measured performance in another combustor with different geometric and thermodynamic characteristics. Without careful interpretation of some key features, the comparison can be misinterpreted and erroneous information used in the design of the new device. This paper provides a review of this performance comparison, including a brief review of the initial liquid rocket scaling research conducted during the 1950s and 1960s, a review of the typical performance losses encountered and how they scale, a description of the typical scaling procedures used in development programs today, and finally a review of several historical development programs to see what insight they can bring to the questions at hand.

  7. One-Dimensional Spontaneous Raman Measurements of Temperature Made in a Gas Turbine Combustor

    NASA Technical Reports Server (NTRS)

    Hicks, Yolanda R.; Locke, Randy J.; DeGroot, Wilhelmus A.; Anderson, Robert C.

    2002-01-01

    The NASA Glenn Research Center is working with the aeronautics industry to develop highly fuel-efficient and environmentally friendly gas turbine combustor technology. This effort includes testing new hardware designs at conditions that simulate the high-temperature, high-pressure environment expected in the next-generation of high-performance engines. Glenn has the only facilities in which such tests can be performed. One aspect of these tests is the use of nonintrusive optical and laser diagnostics to measure combustion species concentration, fuel/air ratio, fuel drop size, and velocity, and to visualize the fuel injector spray pattern and some combustion species distributions. These data not only help designers to determine the efficacy of specific designs, but provide a database for computer modelers and enhance our understanding of the many processes that take place within a combustor. Until recently, we lacked one critical capability, the ability to measure temperature. This article summarizes our latest developments in that area. Recently, we demonstrated the first-ever use of spontaneous Raman scattering to measure combustion temperatures within the Advanced Subsonics Combustion Rig (ASCR) sector rig. We also established the highest rig pressure ever achieved for a continuous-flow combustor facility, 54.4 bar. The ASCR facility can provide operating pressures from 1 to 60 bar (60 atm). This photograph shows the Raman system setup next to the ASCR rig. The test was performed using a NASA-concept fuel injector and Jet-A fuel over a range of air inlet temperatures, pressures, and fuel/air ratios.

  8. Method for operating a combustor in a fuel cell system

    DOEpatents

    Clingerman, Bruce J.; Mowery, Kenneth D.

    2002-01-01

    In one aspect, the invention provides a method of operating a combustor to heat a fuel processor to a desired temperature in a fuel cell system, wherein the fuel processor generates hydrogen (H.sub.2) from a hydrocarbon for reaction within a fuel cell to generate electricity. More particularly, the invention provides a method and select system design features which cooperate to provide a start up mode of operation and a smooth transition from start-up of the combustor and fuel processor to a running mode.

  9. Preliminary studies of combustor sensitivity to alternative fuels

    NASA Technical Reports Server (NTRS)

    Humenik, F. M.

    1980-01-01

    Combustion problems associated with using alternative fuels ground power and aeropropulsion applications were studied. Rectangular sections designed to simulate large annular combustor test conditions were examined. The effects of using alternative fuels with reduced hydrogen content, increased aromatic content, and a broad variation in fuel property characteristics were also studied. Data of special interest were collected which include: flame radiation characteristics in the various combustor zones; the correponding increase in liner temperature from increased radiant heat flux; the effect of fuel bound nitrogen on oxides of nitrogen (NO sub x) emissions; and the overall total effect of fuel variations on exhaust emissions.

  10. Experimental study on premixed CH{sub 4}/air mixture combustion in micro Swiss-roll combustors

    SciTech Connect

    Zhong, Bei-Jing; Wang, Jian-Hua

    2010-12-15

    Excess enthalpy combustion is a promising approach to stabilize flame in micro-combustors. Using a Swiss-roll combustor configuration, excess enthalpy combustion can be conveniently achieved. In this work, three types of Swiss-roll combustors with double spiral-shaped channels were designed and fabricated. The combustors were tested using methane/air mixtures of various equivalence ratios. Both temperature distributions and extinction limits were determined for each combustor configuration at different methane mass flow rates. Results indicate that the Swiss-roll combustors developed in the current study greatly enhance combustion stability in center regions of the combustors. At the same time, excess enthalpy combustors of the Swiss-roll configuration significantly extend the extinction limits of methane/air mixtures. In addition, the effects of combustor configurations and thermal insulation arrangements on temperature distributions and extinction limits were evaluated. With heat losses to the environment being significant, the use of thermal insulations further enhances the flame stability in center regions of the Swiss-roll combustors and extends flammable ranges. (author)

  11. Pulse combustor with controllable oscillations

    DOEpatents

    Richards, George A.; Welter, Michael J.; Morris, Gary J.

    1992-01-01

    A pulse combustor having thermally induced pulse combustion in a continuously flowing system is described. The pulse combustor is fitted with at lease one elongated ceramic body which significantly increases the heat transfer area in the combustion chamber of the combustor. The ceramic body or bodies possess sufficient mass and heat capacity to ignite the fuel-air charge once the ceramic body or bodies are heated by conventional spark plug initiated combustion so as to provide repetitive ignition and combustion of sequentially introduced fuel-air charges without the assistance of the spark plug and the rapid quenching of the flame after each ignition in a controlled manner so as to provide a selective control over the oscillation frequency and amplitude. Additional control over the heat transfer in the combustion chamber is provided by employing heat exchange mechanisms for selectively heating or cooling the elongated ceramic body or bodies and/or the walls of the combustion chamber.

  12. Advances in Design-Based Research

    ERIC Educational Resources Information Center

    Svihla, Vanessa

    2014-01-01

    Design-based research (DBR) is a core methodology of the Learning Sciences. Historically rooted as a movement away from the methods of experimental psychology, it is a means to develop "humble" theory that takes into account numerous contextual effects for understanding how and why a design supported learning. DBR involves iterative…

  13. Coal desulfurization in a rotary kiln combustor

    SciTech Connect

    Cobb, J.T. Jr.

    1992-09-11

    The purpose of this project was to demonstrate the combustion of coal and coal wastes in a rotary kiln reactor with limestone addition for sulfur control. The rationale for the project was the perception that rotary systems could bring several advantages to combustion of these fuels, and may thus offer an alternative to fluid-bed boilers. Towards this end, an existing wood pyrolysis kiln (the Humphrey Charcoal kiln) was to be suitably refurbished and retrofitted with a specially designed version of a patented air distributor provided by Universal Energy, Inc. (UEI). As the project progressed beyond the initial stages, a number of issues were raised regarding the feasibility and the possible advantages of burning coals in a rotary kiln combustor and, in particular, the suitability of the Humphrey Charcoal kiln as a combustor. Instead, an opportunity arose to conduct combustion tests in the PEDCO Rotary Cascading-Bed Boiler (RCBB) commercial demonstration unit at the North American Rayon CO. (NARCO) in Elizabethton, TN. The tests focused on anthracite culm and had two objectives: (a) determine the feasibility of burning anthracite culms in a rotary kiln boiler and (b) obtain input for any further work involving the Humphrey Charcoal kiln combustor. A number of tests were conducted at the PEDCO unit. The last one was conducted on anthracite culm procured directly from the feed bin of a commercial circulating fluid-bed boiler. The results were disappointing; it was difficult to maintain sustained combustion even when large quantities of supplemental fuel were used. Combustion efficiency was poor, around 60 percent. The results suggest that the rotary kiln boiler, as designed, is ill-suited with respect to low-grade, hard to burn solid fuels, such as anthracite culm. Indeed, data from combustion of bituminous coal in the PEDCO unit suggest that with respect to coal in general, the rotary kiln boiler appears inferior to the circulating fluid bed boiler.

  14. Parametric Study of Pulse-Combustor-Driven Ejectors at High-Pressure

    NASA Technical Reports Server (NTRS)

    Yungster, Shaye; Paxson, Daniel E.; Perkins, Hugh D.

    2015-01-01

    Pulse-combustor configurations developed in recent studies have demonstrated performance levels at high-pressure operating conditions comparable to those observed at atmospheric conditions. However, problems related to the way fuel was being distributed within the pulse combustor were still limiting performance. In the first part of this study, new configurations are investigated computationally aimed at improving the fuel distribution and performance of the pulse-combustor. Subsequent sections investigate the performance of various pulse-combustor driven ejector configurations operating at highpressure conditions, focusing on the effects of fuel equivalence ratio and ejector throat area. The goal is to design pulse-combustor-ejector configurations that maximize pressure gain while achieving a thermal environment acceptable to a turbine, and at the same time maintain acceptable levels of NOx emissions and flow non-uniformities. The computations presented here have demonstrated pressure gains of up to 2.8%.

  15. Parametric Study of Pulse-Combustor-Driven Ejectors at High-Pressure

    NASA Technical Reports Server (NTRS)

    Yungster, Shaye; Paxson, Daniel E.; Perkins, Hugh D.

    2015-01-01

    Pulse-combustor configurations developed in recent studies have demonstrated performance levels at high-pressure operating conditions comparable to those observed at atmospheric conditions. However, problems related to the way fuel was being distributed within the pulse combustor were still limiting performance. In the first part of this study, new configurations are investigated computationally aimed at improving the fuel distribution and performance of the pulse-combustor. Subsequent sections investigate the performance of various pulse-combustor driven ejector configurations operating at high pressure conditions, focusing on the effects of fuel equivalence ratio and ejector throat area. The goal is to design pulse-combustor-ejector configurations that maximize pressure gain while achieving a thermal environment acceptable to a turbine, and at the same time maintain acceptable levels of NO(x) emissions and flow non-uniformities. The computations presented here have demonstrated pressure gains of up to 2.8.

  16. The large-amplitude combustion oscillation in a single-side expansion scramjet combustor

    NASA Astrophysics Data System (ADS)

    Ouyang, Hao; Liu, Weidong; Sun, Mingbo

    2015-12-01

    The combustion oscillation in scramjet combustor is believed not existing and ignored for a long time. Compared with the flame pulsation, the large-amplitude combustion oscillation in scramjet combustor is indeed unfamiliar and difficult to be observed. In this study, the specifically designed experiments are carried out to investigate this unusual phenomenon in a single-side expansion scramjet combustor. The entrance parameter of combustor corresponds to scramjet flight Mach number 4.0 with a total temperature of 947 K. The obtained results show that the large-amplitude combustion oscillation can exist in scramjet combustor, which is not occasional and can be reproduced. Under the given conditions of this study, moreover, the large-amplitude combustion oscillation is regular and periodic, whose principal frequency is about 126 Hz. The proceeding of the combustion oscillation is accompanied by the transformation of the flame-holding pattern and combustion mode transition between scramjet mode combustion and ramjet mode combustion.

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

    NASA Technical Reports Server (NTRS)

    Maund, D. H.

    1981-01-01

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

  18. Combustor with fuel preparation chambers

    NASA Technical Reports Server (NTRS)

    Zelina, Joseph (Inventor); Myers, Geoffrey D. (Inventor); Srinivasan, Ram (Inventor); Reynolds, Robert S. (Inventor)

    2001-01-01

    An annular combustor having fuel preparation chambers mounted in the dome of the combustor. The fuel preparation chamber comprises an annular wall extending axially from an inlet to an exit that defines a mixing chamber. Mounted to the inlet are an air swirler and a fuel atomizer. The air swirler provides swirled air to the mixing chamber while the atomizer provides a fuel spray. On the downstream side of the exit, the fuel preparation chamber has an inwardly extending conical wall that compresses the swirling mixture of fuel and air exiting the mixing chamber.

  19. Methanol tailgas combustor control method

    DOEpatents

    Hart-Predmore, David J.; Pettit, William H.

    2002-01-01

    A method for controlling the power and temperature and fuel source of a combustor in a fuel cell apparatus to supply heat to a fuel processor where the combustor has dual fuel inlet streams including a first fuel stream, and a second fuel stream of anode effluent from the fuel cell and reformate from the fuel processor. In all operating modes, an enthalpy balance is determined by regulating the amount of the first and/or second fuel streams and the quantity of the first air flow stream to support fuel processor power requirements.

  20. Computational Design of Advanced Nuclear Fuels

    SciTech Connect

    Savrasov, Sergey; Kotliar, Gabriel; Haule, Kristjan

    2014-06-03

    The objective of the project was to develop a method for theoretical understanding of nuclear fuel materials whose physical and thermophysical properties can be predicted from first principles using a novel dynamical mean field method for electronic structure calculations. We concentrated our study on uranium, plutonium, their oxides, nitrides, carbides, as well as some rare earth materials whose 4f eletrons provide a simplified framework for understanding complex behavior of the f electrons. We addressed the issues connected to the electronic structure, lattice instabilities, phonon and magnon dynamics as well as thermal conductivity. This allowed us to evaluate characteristics of advanced nuclear fuel systems using computer based simulations and avoid costly experiments.

  1. Advanced solar concentrator: Preliminary and detailed design

    NASA Technical Reports Server (NTRS)

    Bell, D. M.; Maraschin, R. A.; Matsushita, M. T.; Erskine, D.; Carlton, R.; Jakovcevic, A.; Yasuda, A. K.

    1981-01-01

    A single reflection point focusing two-axis tracking paraboloidal dish with a reflector aperture diameter of approximately 11 m has a reflective surface made up of 64 independent, optical quality gores. Each gore is a composite of a thin backsilvered mirror glass face sheet continuously bonded to a contoured substrate of lightweight, rigid cellular glass. The use of largely self-supporting gores allows a significant reduction in the weight of the steel support structure as compared to alternate design concepts. Primary emphasis in the preliminary design package for the low-cost, low-weight, mass producible concentrator was placed on the design of the higher cost subsystems. The outer gore element was sufficiently designed to allow fabrication of prototype gores.

  2. NASA/USRA advanced design program

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This report analyzes and presents a preliminary design for an experimental hypersonic vehicle. This plane will have a cruise speed of Mach 12 for one minute at an altitude of 120,000 feet. The major design areas of aerodynamics, propulsion, and weights are discussed in depth. An elementary analysis of thermal protection, trajectory, and cost is also presented. Finally, a discussion of future plans and recommendations is given, and overall conclusions are drawn.

  3. Improved Controllers For Heaters In Toxic-Gas Combustors

    NASA Technical Reports Server (NTRS)

    Wishard, James; Lamb, James; Fortier, Edward; Velasquez, Hugo; Waltman, Doug

    1995-01-01

    Commercial electronic proportional controllers installed in place of mechanical power controllers for electric heaters in toxic-gas combustors at NASA's Jet Propulsion Laboratory. Designed to maintain temperature of heater at preset value by turning power fully on or fully off when temperature falls below or rises above that value, respectively. Solid-state power controllers overcome deficiencies of mechanical power controllers.

  4. MHD coal combustor technology. Final report, phase II

    SciTech Connect

    Not Available

    1980-09-01

    The design, performance, and testing of a 20-MW coal combustor for scaleup to 50 MW for use in an MHD generator are described. The design incorporates the following key features: (1) a two-stage combustor with an intermediate slag separator to remove slag at a low temperture, thus minimizing enthalpy losses required for heating and vaporizing the slag; (2) a first-stage pentad (four air streams impinging on one coal stream) injector design with demonstrated efficient mixing, promoting high carbon burnout; (3) a two-section first-stage combustion chamber; the first stage using a thin slag-protected refractory layer and the second section using a thick refractory layer, both to minimize heat losses; (4) a refractory lining in the slag separator to minimize heat losses; (5) a second-stage combustor, which provided both de-swirl of the combustion products exiting from the slag separator and simple mixing of the vitiated secondary air and seed; (6) a dense-phase coal feed system to minimize cold carrier gas entering the first-stage combustors; (7) a dry seed injection system using pulverized K/sub 2/CO/sub 3/ with a 1% amorphous, fumed silicon dioxide additive to enhance flowability, resulting in rapid vaporization and ionization and ensuring maximum performance; and (8) a performance evaluation module (PEM) of rugged design based on an existing, successfully-fired unit. (WHK)

  5. MUNICIPAL SOLID WASTE COMBUSTOR ASH DEMONSTRATION PROGRAM - "THE BOATHOUSE"

    EPA Science Inventory

    The report presents the results of a research program designed to examine the engineering and environmental acceptability of using municipal solid waste (MSW) combustor ash as an aggregate substitute in the manufacture of construction quality cement blocks. 50 tons of MSW combust...

  6. DEVELOPMENT OF A VORTEX CONTAINMENT COMBUSTOR FOR COAL COMBUSTION SYTEMS

    EPA Science Inventory

    The report describes the development of a vortex containment combustor (VCC) for coal combustion systems, designed to solve major problems facing the conversion of oil- and gas-fired boilers to coal (e.g., derating, inorganic impurities in coal, and excessive formation of NOx and...

  7. Small gas turbine combustor study: Fuel injector performance in a transpiration-cooled liner

    NASA Technical Reports Server (NTRS)

    Riddlebaugh, S. M.; Norgren, C. T.

    1985-01-01

    The effect of fuel injection technique on the performance of an advanced reverse flow combustor liner constructed of Lamilloy (a multilaminate transpiration type material) was determined. Performance and emission levels are documented over a range of simulated flight conditions using simplex pressure atomizing, spill return, and splash cone airblast injectors. A parametric evaluation of the effect of increased combustor loading with each of the fuel injector types is obtained.

  8. Small gas turbine combustor study - Fuel injector performance in a transpiration-cooled liner

    NASA Technical Reports Server (NTRS)

    Riddlebaugh, S. M.; Norgren, C. T.

    1985-01-01

    The effect of fuel injection technique on the performance of an advanced reverse flow combustor liner constructed of Lamilloy (a multilaminate transpiration type material) was determined. Performance and emission levels are documented over a range of simulated flight conditions using simplex pressure atomizing, spill return, and splash cone airblast injectors. A parametric evaluation of the effect of increased combustor loading with each of the fuel injector types is obtained.

  9. Energy Efficient Engine: Combustor component performance program

    NASA Technical Reports Server (NTRS)

    Dubiel, D. J.

    1986-01-01

    The results of the Combustor Component Performance analysis as developed under the Energy Efficient Engine (EEE) program are presented. This study was conducted to demonstrate the aerothermal and environmental goals established for the EEE program and to identify areas where refinements might be made to meet future combustor requirements. In this study, a full annular combustor test rig was used to establish emission levels and combustor performance for comparison with those indicated by the supporting technology program. In addition, a combustor sector test rig was employed to examine differences in emissions and liner temperatures obtained during the full annular performance and supporting technology tests.

  10. [Advances of portable electrocardiogram monitor design].

    PubMed

    Ding, Shenping; Wang, Yinghai; Wu, Weirong; Deng, Lingli; Lu, Jidong

    2014-06-01

    Portable electrocardiogram monitor is an important equipment in the clinical diagnosis of cardiovascular diseases due to its portable, real-time features. It has a broad application and development prospects in China. In the present review, previous researches on the portable electrocardiogram monitors have been arranged, analyzed and summarized. According to the characteristics of the electrocardiogram (ECG), this paper discusses the ergonomic design of the portable electrocardiogram monitor, including hardware and software. The circuit components and software modules were parsed from the ECG features and system functions. Finally, the development trend and reference are provided for the portable electrocardiogram monitors and for the subsequent research and product design.

  11. Reconfigurable Advanced Receiver Design and Implementation

    NASA Technical Reports Server (NTRS)

    Xu, Jianjing

    2005-01-01

    While the demand for real-time broadband information access has grown and continues to grow at a rapid Pace, the need for a reconfigurable receiver system has increased. To achieve the goal to communicate with multiple shuttles at a time, a filter bank in polyphase structure is introduced. This paper presents the design and implementation for high-speed, high-performance, and fixed-point polyphase filter banks. The polyphase filter structure is designed such that the use of a fixed-point system has minimum impact on the performance of the filter. The final hardware implementation is done on a Xilinx FPGA chip.

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

    SciTech Connect

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

    1987-01-01

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

  13. Orbit transfer rocket engine technology program enhanced heat transfer combustor technology

    NASA Astrophysics Data System (ADS)

    Brown, William S.

    1991-12-01

    In order to increase the performance of a high performance, advanced expander-cycle engine combustor, higher chamber pressures are required. In order to increase chamber pressure, more heat energy is required to be transferred to the combustor coolant circuit fluid which drives the turbomachinery. This requirement was fulfilled by increasing the area exposed to the hot-gas by using combustor ribs. A previous technology task conducted 2-d hot air and cold flow tests to determine an optimum rib height and configuration. In task C.5 a combustor calorimeter was fabricated with the optimum rib configuration, 0.040 in. high ribs, in order to determine their enhancing capability. A secondary objective was to determine the effects of mixture ratio changers on the enhancement during hot-fire testing. The program used the Rocketdyne Integrated Component Evaluator (ICE) reconfigured into a thrust chamber only mode. The test results were extrapolated to give a projected enhancement from the ribs for a 16 in. long cylindrical combustor at 15 Klb nominal thrust level. The hot-gas wall ribs resulted in a 58 percent increase in heat transfer. When projected to a full size 15K combustor, it becomes a 46 percent increase. The results of those tests, a comparison with previous 2-d results, the effects of mixture ratio and combustion gas flow on the ribs and the potential ramifications for expander cycle combustors are detailed.

  14. CFD analysis of jet mixing in low NOx flametube combustors

    NASA Technical Reports Server (NTRS)

    Talpallikar, M. V.; Smith, C. E.; Lai, M. C.; Holdeman, J. D.

    1991-01-01

    The Rich-burn/Quick-mix/Lean-burn (RQL) combustor was identified as a potential gas turbine combustor concept to reduce NO(x) emissions in High Speed Civil Transport (HSCT) aircraft. To demonstrate reduced NO(x) levels, cylindrical flametube versions of RQL combustors are being tested at NASA Lewis Research Center. A critical technology needed for the RQL combustor is a method of quickly mixing by-pass combustion air with rich-burn gases. Jet mixing in a cylindrical quick-mix section was numerically analyzed. The quick-mix configuration was five inches in diameter and employed twelve radial-inflow slots. The numerical analyses were performed with an advanced, validated 3-D Computational Fluid Dynamics (CFD) code named REFLEQS. Parametric variation of jet-to-mainstream momentum flux ratio (J) and slot aspect ratio was investigated. Both non-reacting and reacting analyses were performed. Results showed mixing and NO(x) emissions to be highly sensitive to J and slot aspect ratio. Lowest NO(x) emissions occurred when the dilution jet penetrated to approximately mid-radius. The viability of using 3-D CFD analyses for optimizing jet mixing was demonstrated.

  15. NASA Lewis Research Center's Preheated Combustor and Materials Test Facility

    NASA Technical Reports Server (NTRS)

    Nemets, Steve A.; Ehlers, Robert C.; Parrott, Edith

    1995-01-01

    The Preheated Combustor and Materials Test Facility (PCMTF) in the Engine Research Building (ERB) at the NASA Lewis Research Center is one of two unique combustor facilities that provide a nonvitiated air supply to two test stands, where the air can be used for research combustor testing and high-temperature materials testing. Stand A is used as a research combustor stand, whereas stand B is used for cyclic and survivability tests of aerospace materials at high temperatures. Both stands can accommodate in-house and private industry research programs. The PCMTF is capable of providing up to 30 lb/s (pps) of nonvitiated, 450 psig combustion air at temperatures ranging from 850 to 1150 g F. A 5000 gal tank located outdoors adjacent to the test facility can provide jet fuel at a pressure of 900 psig and a flow rate of 11 gal/min (gpm). Gaseous hydrogen from a 70,000 cu ft (CF) tuber is also available as a fuel. Approximately 500 gpm of cooling water cools the research hardware and exhaust gases. Such cooling is necessary because the air stream reaches temperatures as high as 3000 deg F. The PCMTF provides industry and Government with a facility for studying the combustion process and for obtaining valuable test information on advanced materials. This report describes the facility's support systems and unique capabilities.

  16. Advanced Computational Techniques for Power Tube Design.

    DTIC Science & Technology

    1986-07-01

    fixturing applications, in addition to the existing computer-aided engineering capabilities. o Helix TWT Manufacturing has Implemented a tooling and fixturing...illustrates the ajor features of this computer network. ) The backbone of our system is a Sytek Broadband Network (LAN) which Interconnects terminals and...automatic network analyzer (FANA) which electrically characterizes the slow-wave helices of traveling-wave tubes ( TWTs ) -- both for engineering design

  17. Advanced designs for fluid flow visualization

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Research was carried out on existing and new designs for minimally intrusive measurement of flow fields in the Geophysical Fluid Flow Cell and the proposed Atmospheric General Circulation Experiment. The following topics are discussed: (1) identification and removal of foreign particles, (2) search for higher dielectric photochromic solutions, (3) selection of uv light source, (4) analysis of refractive techniques and (5) examination of fresnel lens applicability.

  18. Advances in structure-based vaccine design

    PubMed Central

    Kulp, Daniel W; Schief, William R

    2014-01-01

    Despite the tremendous successes of current vaccines, infectious diseases still take a heavy toll on the global population, and that provides strong rationale for broadening our vaccine development repertoire. Structural vaccinology, in which protein structure information is utilized to design immunogens, has promise to provide new vaccines against traditionally difficult targets. Crystal structures of antigens containing one or more protection epitopes, especially when in complex with a protective antibody, are the launching point for immunogen design. Integrating structure and sequence information for families of broadly neutralizing antibodies (bNAbs) has recently enabled the creation of germline-targeting immunogens that bind and activate germline B-cells in order to initiate the elicitation of such antibodies. The contacts between antigen and neutralizing antibody define a structural epitope, and methods have been developed to transplant epitopes to scaffold proteins for structural stabilization, and to design minimized antigens that retain one or more key epitopes while eliminating other potentially distracting or unnecessary features. To develop vaccines that protect against antigenically variable pathogens, pioneering structure-based work demonstrated that multiple strain-specific epitopes could be engineered onto a single immunogen. We review these recent structural vaccinology efforts to engineer germline-targeting, epitope-specific, and/or broad coverage immunogens. PMID:23806515

  19. TMF design considerations in turbine airfoils of advanced turbine engines

    NASA Astrophysics Data System (ADS)

    Date, C. G.; Zamrik, S. Y.; Adams, J. H.; Frani, N. E.

    A review of thermal-mechanicalfatigue (TMF) in advanced turbine engines is presented. The review includes examples of typical thermal-mechnical loadings encountered in the design of hot section blades and vanes. Specific issues related to TMF behavior are presented and the associated impact on component life analysis and design is discussed.

  20. Design, analysis and test verification of advanced encapsulation systems

    NASA Technical Reports Server (NTRS)

    Garcia, A., III

    1983-01-01

    The analytical methodology for advanced encapsulation designs for the development of photovoltaic modules is presented. Analytical models are developed to test optical, thermal, electrical and structural properties of the various encapsulation systems. Model data is compared to relevant test data to improve model accuracy and develop general principles for the design of photovoltaic modules.

  1. Engineering Design Handbook. Joining of Advanced Composites

    DTIC Science & Technology

    1979-03-01

    347 A0-830 291 350 AD·881 357 355 A0830 268 356 AD-817 023 357 AD-873 103 3591 ADA-035 445 360 A0-783 697 361 AOA-013 769 4101 AOA- 038 803...A0·873 103 3581 ADA·035 445 360 AD·7B3 697 361 ADA·013 769 4101 AOA· 038 803 411 lSI AOC·008 827 412 ICI ADC·OOB 828 413iS) ADC·OOB 829 414...t17. 50 Helicopter Engineering. Part Two, Detail Design

  2. Advanced EVA system design requirements study

    NASA Technical Reports Server (NTRS)

    Woods, T. G.

    1988-01-01

    The results are presented of a study to identify specific criteria regarding space station extravehicular activity system (EVAS) hardware requirements. Key EVA design issues include maintainability, technology readiness, LSS volume vs. EVA time available, suit pressure/cabin pressure relationship and productivity effects, crew autonomy, integration of EVA as a program resource, and standardization of task interfaces. A variety of DOD EVA systems issues were taken into consideration. Recommendations include: (1) crew limitations, not hardware limitations; (2) capability to perform all of 15 generic missions; (3) 90 days on-orbit maintainability with 50 percent duty cycle as minimum; and (4) use by payload sponsors of JSC document 10615A plus a Generic Tool Kit and Specialized Tool Kit description. EVA baseline design requirements and criteria, including requirements of various subsystems, are outlined. Space station/EVA system interface requirements and EVA accommodations are discussed in the areas of atmosphere composition and pressure, communications, data management, logistics, safe haven, SS exterior and interior requirements, and SS airlock.

  3. Liquid rocket combustor computer code development

    NASA Technical Reports Server (NTRS)

    Liang, P. Y.

    1985-01-01

    The Advanced Rocket Injector/Combustor Code (ARICC) that has been developed to model the complete chemical/fluid/thermal processes occurring inside rocket combustion chambers are highlighted. The code, derived from the CONCHAS-SPRAY code originally developed at Los Alamos National Laboratory incorporates powerful features such as the ability to model complex injector combustion chamber geometries, Lagrangian tracking of droplets, full chemical equilibrium and kinetic reactions for multiple species, a fractional volume of fluid (VOF) description of liquid jet injection in addition to the gaseous phase fluid dynamics, and turbulent mass, energy, and momentum transport. Atomization and droplet dynamic models from earlier generation codes are transplated into the present code. Currently, ARICC is specialized for liquid oxygen/hydrogen propellants, although other fuel/oxidizer pairs can be easily substituted.

  4. Design considerations for advanced battery concepts

    NASA Technical Reports Server (NTRS)

    Leibecki, H. F.; Thaller, L. H.

    1986-01-01

    A mathematical representation for the charge and discharge of a sodium-sulfur cell is developed. These equations are then used as the basis for a computerized model to examine the effects of cell arrangement in the design of a large multi-kilowatt battery from a group of hypothetical individual cells with known variations in their ampere hour capacity and internal resistance. The cycling characteristics of 216 individual cells arranged in six different configurations are evaluated with the view towards minimizing the adverse effects that are introduced due to the stoichastic aspects of groupings of cells, as well as the possibility of cell failures in both the open and shorted mode. Although battery systems based on sodium-sulfur cells are described in this example, any of the newer electrochemical systems can be fitted into this framework by making appropriate modifications to the basic equations.

  5. Robust flight design for an advanced launch system vehicle

    NASA Technical Reports Server (NTRS)

    Dhand, Sanjeev K.; Wong, Kelvin K.

    1991-01-01

    Current launch vehicle trajectory design philosophies are generally based on maximizing payload capability. This approach results in an expensive trajectory design process for each mission. Two concepts of robust flight design have been developed to significantly reduce this cost: Standardized Trajectories and Command Multiplier Steering (CMS). These concepts were analyzed for an Advanced Launch System (ALS) vehicle, although their applicability is not restricted to any particular vehicle. Preliminary analysis has demonstrated the feasibility of these concepts at minimal loss in payload capability.

  6. CFD analyses for advanced pump design

    NASA Technical Reports Server (NTRS)

    Dejong, F. J.; Choi, S.-K.; Govindan, T. R.

    1994-01-01

    As one of the activities of the NASA/MSFC Pump Stage Technology Team, the present effort was focused on using CFD in the design and analysis of high performance rocket engine pumps. Under this effort, a three-dimensional Navier-Stokes code was used for various inducer and impeller flow field calculations. An existing algebraic grid generation procedure was-extended to allow for nonzero blade thickness, splitter blades, and hub/shroud cavities upstream or downstream of the (main) blades. This resulted in a fast, robust inducer/impeller geometry/grid generation package. Problems associated with running a compressible flow code to simulate an incompressible flow were resolved; related aspects of the numerical algorithm (viz., the matrix preconditioning, the artificial dissipation, and the treatment of low Mach number flows) were addressed. As shown by the calculations performed under the present effort, the resulting code, in conjunction with the grid generation package, is an effective tool for the rapid solution of three-dimensional viscous inducer and impeller flows.

  7. Preliminary design studies of an advanced general aviation aircraft

    NASA Technical Reports Server (NTRS)

    Barrett, Ron; Demoss, Shane; Dirkzwager, AB; Evans, Darryl; Gomer, Charles; Keiter, Jerry; Knipp, Darren; Seier, Glen; Smith, Steve; Wenninger, ED

    1991-01-01

    The preliminary design results are presented of the advanced aircraft design project. The goal was to take a revolutionary look into the design of a general aviation aircraft. Phase 1 of the project included the preliminary design of two configurations, a pusher, and a tractor. Phase 2 included the selection of only one configuration for further study. The pusher configuration was selected on the basis of performance characteristics, cabin noise, natural laminar flow, and system layouts. The design was then iterated to achieve higher levels of performance.

  8. Effects of Burning Alternative Fuel in a 5-Cup Combustor Sector

    NASA Technical Reports Server (NTRS)

    Tacina, K. M.; Chang, C. T.; Lee, C.-M.; He, Z.; Herbon, J.

    2015-01-01

    A goal of NASA's Environmentally Responsible Aviation (ERA) program is to develop a combustor that will reduce the NOx emissions and that can burn both standard and alternative fuels. To meet this goal, NASA partnered with General Electric Aviation to develop a 5-cup combustor sector; this sector was tested in NASA Glenn's Advanced Subsonic Combustion Rig (ASCR). To verify that the combustor sector was fuel-flexible, it was tested with a 50-50 blend of JP-8 and a biofuel made from the camelina sativa plant. Results from this test were compared to results from tests where the fuel was neat JP-8. Testing was done at three combustor inlet conditions: cruise, 30% power, and 7% power. When compared to burning JP-8, burning the 50-50 blend did not significantly affect emissions of NOx, CO, or total hydrocarbons. Furthermore, it did not significantly affect the magnitude and frequency of the dynamic pressure fluctuations.

  9. Coherent anti-Stokes Raman scattering for quantitative temperature and concentration measurements in a high-pressure gas turbine combustor rig

    NASA Astrophysics Data System (ADS)

    Thariyan, Mathew Paul

    Dual-pump coherent anti-Stokes Raman scattering (DP-CARS) temperature and major species (CO2/N2) concentration measurements have been performed in an optically-accessible high-pressure gas turbine combustor facility (GTCF) and for partially-premixed and non-premixed flames in a laminar counter-flow burner. A window assembly incorporating pairs of thin and thick fused silica windows on three sides was designed, fabricated, and assembled in the GTCF for advanced laser diagnostic studies. An injection-seeded optical parametric oscillator (OPO) was used as a narrowband pump laser source in the dual-pump CARS system. Large prisms on computer-controlled translation stages were used to direct the CARS beams either into the main optics leg for measurements in the GTCF or to a reference optics leg for measurements of the nonresonant CARS spectrum and for aligning the CARS system. Combusting flows were stabilized with liquid fuel injection only for the central injector of a 9-element lean direct injection (LDI) device developed at NASA Glenn Research Center. The combustor was operated using Jet A fuel at inlet air temperatures up to 725 K and combustor pressures up to 1.03 MPa. Single-shot DP-CARS spectra were analyzed using the Sandia CARSFT code in the batch operation mode to yield instantaneous temperature and CO2/N2 concentration ratio values. Spatial maps of mean and standard deviations of temperature and CO2/N2 concentrations were obtained in the high-pressure LDI flames by translating the CARS probe volume in axial and vertical directions inside the combustor rig. The mean temperature fields demonstrate the effect of the combustor conditions on the overall flame length and the average flame structure. The temperature relative standard deviation values indicate thermal fluctuations due to the presence of recirculation zones and/or flame brush fluctuations. The correlation between the temperature and relative CO 2 concentration data has been studied at various combustor

  10. Synthetic biology: advancing the design of diverse genetic systems

    PubMed Central

    Wang, Yen-Hsiang; Wei, Kathy Y.; Smolke, Christina D.

    2013-01-01

    A main objective of synthetic biology is to make the process of designing genetically-encoded biological systems more systematic, predictable, robust, scalable, and efficient. The examples of genetic systems in the field vary widely in terms of operating hosts, compositional approaches, and network complexity, ranging from a simple genetic switch to search-and-destroy systems. While significant advances in synthesis capabilities support the potential for the implementation of pathway- and genome-scale programs, several design challenges currently restrict the scale of systems that can be reasonably designed and implemented. Synthetic biology offers much promise in developing systems to address challenges faced in manufacturing, the environment and sustainability, and health and medicine, but the realization of this potential is currently limited by the diversity of available parts and effective design frameworks. As researchers make progress in bridging this design gap, advances in the field hint at ever more diverse applications for biological systems. PMID:23413816

  11. Advanced Combustion Systems for Next Generation Gas Turbines

    SciTech Connect

    Joel Haynes; Jonathan Janssen; Craig Russell; Marcus Huffman

    2006-01-01

    Next generation turbine power plants will require high efficiency gas turbines with higher pressure ratios and turbine inlet temperatures than currently available. These increases in gas turbine cycle conditions will tend to increase NOx emissions. As the desire for higher efficiency drives pressure ratios and turbine inlet temperatures ever higher, gas turbines equipped with both lean premixed combustors and selective catalytic reduction after treatment eventually will be unable to meet the new emission goals of sub-3 ppm NOx. New gas turbine combustors are needed with lower emissions than the current state-of-the-art lean premixed combustors. In this program an advanced combustion system for the next generation of gas turbines is being developed with the goal of reducing combustor NOx emissions by 50% below the state-of-the-art. Dry Low NOx (DLN) technology is the current leader in NOx emission technology, guaranteeing 9 ppm NOx emissions for heavy duty F class gas turbines. This development program is directed at exploring advanced concepts which hold promise for meeting the low emissions targets. The trapped vortex combustor is an advanced concept in combustor design. It has been studied widely for aircraft engine applications because it has demonstrated the ability to maintain a stable flame over a wide range of fuel flow rates. Additionally, it has shown significantly lower NOx emission than a typical aircraft engine combustor and with low CO at the same time. The rapid CO burnout and low NOx production of this combustor made it a strong candidate for investigation. Incremental improvements to the DLN technology have not brought the dramatic improvements that are targeted in this program. A revolutionary combustor design is being explored because it captures many of the critical features needed to significantly reduce emissions. Experimental measurements of the combustor performance at atmospheric conditions were completed in the first phase of the program

  12. WRAP 2A advanced conceptual design report comments

    SciTech Connect

    Lamberd, D.L.

    1994-10-04

    This report contains the compilation of the 393 comments that were submitted during the review of the Advanced Conceptual Design Report for the Waste Receiving and Processing Facility Module 2A. The report was prepared by Raytheon Engineers and Constructors, Inc. of Englewood, Colorado for the United States Department of Energy. The review was performed by a variety of organizations identified in the report. The comments were addressed first by the Westinghouse cognizant engineers and then by the Raytheon cognizant engineers, and incorporated into the final issue of the Advanced Conceptual Design Report.

  13. ADVANCED TURBINE SYSTEM CONCEPTUAL DESIGN AND PRODUCT DEVELOPMENT - Final Report

    SciTech Connect

    Albrecht H. Mayer

    2000-07-15

    Asea Brown Boveri (ABB) has completed its technology based program. The results developed under Work Breakdown Structure (WBS) 8, concentrated on technology development and demonstration have been partially implemented in newer turbine designs. A significant improvement in heat rate and power output has been demonstrated. ABB will use the knowledge gained to further improve the efficiency of its Advanced Cycle System, which has been developed and introduced into the marked out side ABB's Advanced Turbine System (ATS) activities. The technology will lead to a power plant design that meets the ATS performance goals of over 60% plant efficiency, decreased electricity costs to consumers and lowest emissions.

  14. An Experimental Investigation of Self-Excited Combustion Dynamics in a Single Element Lean Direct Injection (LDI) Combustor

    NASA Astrophysics Data System (ADS)

    Gejji, Rohan M.

    The management of combustion dynamics in gas turbine combustors has become more challenging as strict NOx/CO emission standards have led to engine operation in a narrow, lean regime. While premixed or partially premixed combustor configurations such as the Lean Premixed Pre-vaporized (LPP), Rich Quench Lean burn (RQL), and Lean Direct Injection (LDI) have shown a potential for reduced NOx emissions, they promote a coupling between acoustics, hydrodynamics and combustion that can lead to combustion instabilities. These couplings can be quite complex, and their detailed understanding is a pre-requisite to any engine development program and for the development of predictive capability for combustion instabilities through high-fidelity models. The overarching goal of this project is to assess the capability of high-fidelity simulation to predict combustion dynamics in low-emissions gas turbine combustors. A prototypical lean-direct-inject combustor was designed in a modular configuration so that a suitable geometry could be found by test. The combustor comprised a variable length air plenum and combustion chamber, air swirler, and fuel nozzle located inside a subsonic venturi. The venturi cross section and the fuel nozzle were consistent with previous studies. Test pressure was 1 MPa and variables included geometry and acoustic resonance, inlet temperatures, equivalence ratio, and type of liquid fuel. High-frequency pressure measurements in a well-instrumented metal chamber yielded frequencies and mode shapes as a function of inlet air temperature, equivalence ratio, fuel nozzle placement, and combustor acoustic resonances. The parametric survey was a significant effort, with over 105 tests on eight geometric configurations. A good dataset was obtained that could be used for both operating-point-dependent quantitative comparisons, and testing the ability of the simulation to predict more global trends. Results showed a very strong dependence of instability amplitude on

  15. Variable residence time vortex combustor

    DOEpatents

    Melconian, Jerry O.

    1987-01-01

    A variable residence time vortex combustor including a primary combustion chamber for containing a combustion vortex, and a plurality of louvres peripherally disposed about the primary combustion chamber and longitudinally distributed along its primary axis. The louvres are inclined to impel air about the primary combustion chamber to cool its interior surfaces and to impel air inwardly to assist in driving the combustion vortex in a first rotational direction and to feed combustion in the primary combustion chamber. The vortex combustor also includes a second combustion chamber having a secondary zone and a narrowed waist region in the primary combustion chamber interconnecting the output of the primary combustion chamber with the secondary zone for passing only lower density particles and trapping higher density particles in the combustion vortex in the primary combustion chamber for substantial combustion.

  16. Proceedings of the Ninth Annual Summer Conference: NASA/USRA University Advanced Aeronautics Design Program and Advanced Space Design Program

    NASA Technical Reports Server (NTRS)

    1993-01-01

    The NASA/USRA University Advanced Design Program was established in 1984 as an attempt to add more and better design education to primarily undergraduate engineering programs. The original focus of the pilot program encompassing nine universities and five NASA centers was on space design. Two years later, the program was expanded to include aeronautics design with six universities and three NASA centers participating. This year marks the last of a three-year cycle of participation by forty-one universities, eight NASA centers, and one industry participant. The Advanced Space Design Program offers universities an opportunity to plan and design missions and hardware that would be of usc in the future as NASA enters a new era of exploration and discovery, while the Advanced Aeronautics Design Program generally offers opportunities for study of design problems closer to the present time, ranging from small, slow-speed vehicles to large, supersonic and hypersonic passenger transports. The systems approach to the design problem is emphasized in both the space and aeronautics projects. The student teams pursue the chosen problem during their senior year in a one- or two-semester capstone design course and submit a comprehensive written report at the conclusion of the project. Finally, student representatives from each of the universities summarize their work in oral presentations at the Annual Summer Conference, sponsored by one of the NASA centers and attended by the university faculty, NASA and USRA personnel and aerospace industry representatives. As the Advanced Design Program has grown in size, it has also matured in terms of the quality of the student projects. The present volume represents the student work accomplished during the 1992-1993 academic year reported at the Ninth Annual Summer Conference hosted by NASA Lyndon B. Johnson Space Center, June 14-18, 1993.

  17. Aerodynamic Design Study of Advanced Multistage Axial Compressor

    NASA Technical Reports Server (NTRS)

    Larosiliere, Louis M.; Wood, Jerry R.; Hathaway, Michael D.; Medd, Adam J.; Dang, Thong Q.

    2002-01-01

    As a direct response to the need for further performance gains from current multistage axial compressors, an investigation of advanced aerodynamic design concepts that will lead to compact, high-efficiency, and wide-operability configurations is being pursued. Part I of this report describes the projected level of technical advancement relative to the state of the art and quantifies it in terms of basic aerodynamic technology elements of current design systems. A rational enhancement of these elements is shown to lead to a substantial expansion of the design and operability space. Aerodynamic design considerations for a four-stage core compressor intended to serve as a vehicle to develop, integrate, and demonstrate aerotechnology advancements are discussed. This design is biased toward high efficiency at high loading. Three-dimensional blading and spanwise tailoring of vector diagrams guided by computational fluid dynamics (CFD) are used to manage the aerodynamics of the high-loaded endwall regions. Certain deleterious flow features, such as leakage-vortex-dominated endwall flow and strong shock-boundary-layer interactions, were identified and targeted for improvement. However, the preliminary results were encouraging and the front two stages were extracted for further aerodynamic trimming using a three-dimensional inverse design method described in part II of this report. The benefits of the inverse design method are illustrated by developing an appropriate pressure-loading strategy for transonic blading and applying it to reblade the rotors in the front two stages of the four-stage configuration. Multistage CFD simulations based on the average passage formulation indicated an overall efficiency potential far exceeding current practice for the front two stages. Results of the CFD simulation at the aerodynamic design point are interrogated to identify areas requiring additional development. In spite of the significantly higher aerodynamic loadings, advanced CFD

  18. Design, analysis and test verification of advanced encapsulation systems

    NASA Technical Reports Server (NTRS)

    Garcia, A., III

    1982-01-01

    An analytical methodology for advanced encapsulation designs was developed. From these methods design sensitivities are established for the development of photovoltaic module criteria and the definition of needed research tasks. Analytical models were developed to perform optical, thermal, electrical and analyses on candidate encapsulation systems. From these analyses several candidate systems were selected for qualification testing. Additionally, test specimens of various types are constructed and tested to determine the validity of the analysis methodology developed. Identified deficiencies and/or discrepancies between analytical models and relevant test data are corrected. Prediction capability of analytical models is improved. Encapsulation engineering generalities, principles, and design aids for photovoltaic module designers is generated.

  19. Coherent Anti-Stokes Raman Spectroscopic Thermometry in a Supersonic Combustor

    NASA Technical Reports Server (NTRS)

    Cutler, A. D.; Danehy, P. M.; Springer, R. R.; OByrne, S.; Capriotti, D. P.; DeLoach, R.

    2003-01-01

    An experiment has been conducted to acquire data for the validation of computational fluid dynamics codes used in the design of supersonic combustors. The flow in a supersonic combustor, consisting of a diverging duct with a single downstream-angled wail injector, is studied. Combustor entrance Mach number is 2 and enthalpy nominally corresponds to Mach 7 flight. The primary measurement technique is coherent anti-Stokes Raman spectroscopy, but surface pressures and temperatures have also been acquired. Modern design of experiment techniques have been used to maximize the quality of the data set (for the given level of effort) and to minimize systematic errors. Temperature maps are obtained at several planes in the flow for a case in which the combustor is piloted by injecting fuel upstream of the main injector and one case in which it is not piloted. Boundary conditions and uncertainties are characterized.

  20. Combustor with multistage internal vortices

    DOEpatents

    Shang, Jer Yu; Harrington, R.E.

    1987-05-01

    A fluidized bed combustor is provided with a multistage arrangement of vortex generators in the freeboard area. The vortex generators are provided by nozzle means which extend into the interior of the freeboard for forming vortices within the freeboard areas to enhance the combustion of particulate material entrained in product gases ascending into the freeboard from the fluidized bed. Each of the nozzles are radially inwardly spaced from the combustor walls defining the freeboard to provide for the formation of an essentially vortex-free, vertically extending annulus about the vortices whereby the particulate material centrifuged from the vortices against the inner walls of the combustor is returned through the annulus to the fluidized bed. By adjusting the vortex pattern within the freeboard, a significant portion of the full cross-sectional area of the freeboard except for the peripheral annulus can be contacted with the turbulent vortical flow for removing the particulate material from the gaseous products and also for enhancing the combustion thereof within the freeboard. 2 figs.

  1. Vertical combustor for particulate refuse

    NASA Astrophysics Data System (ADS)

    Chung, P. M.; Carlson, L.

    1981-03-01

    A one-dimensional model is constructed of a vertical combustor for refuse particle combustion in order to analyze it for waste energy recovery. The three components of the model, fuel particles, inert solid particles and the gaseous mixture are described by momentum, energy, and mass conservation equations, resulting in three different flow velocities and temperatures for the medium. The gaseous component is further divided into six chemical species that evolve in combustion at temperatures below about 1367 K. A detailed description is given of the fuel particle combustion through heating, devolatilization, and combustion of the volatile gas in the boundary layer, return of the flame sheet to the fuel surface, and char combustion. The solutions show the combustor to be viable for U.S. refuse which consists of combustibles that can be volatilized up to 85 to 95% below 1366 K. Char combustion, however, is found to be too slow to be attempted in the combustor, where the fuel residence time is of the order of 2 s.

  2. Numerical investigation of enhanced dilution zone mixing in a reverse flow gas turbine combustor

    NASA Astrophysics Data System (ADS)

    Crocker, D. S.; Smith, C. E.

    1995-04-01

    An advanced method for dilution zone mixing in a reverse flow gas turbine combustor was numerically investigated. For long mixing lengths associated with reverse flow combustors (X/H greater than 2.0), pattern factor was found to be mainly driven by nozzle-to-nozzle fuel flow and/or circumferential airflow variations; conventional radially injected dilution jets could not effectively mix out circumferential nonuniformities. To enhance circumferential mixing, dilution jets were angled to produce a high circumferential (swirl) velocity component. The jets on the outer liner were angled in one direction while the jets on the inner liner were angled in the opposite direction, thus enhancing turbulent shear at the expense of jet penetration. Three-dimensional CFD calculations were performed on a three-nozzle (90 deg) sector, with different fuel flow from each nozzle (90, 100, and 110% of design fuel flow). The computations showed that the optimum configuration of angled jets reduced the pattern factor by 60% compared to an existing conventional dilution hole configuration. The radial average temperature profile was adequately controlled by the inner-to-outer liner dilution flow split.

  3. Advanced radial inflow turbine rotor program: Design and dynamic testing

    NASA Technical Reports Server (NTRS)

    Rodgers, C.

    1976-01-01

    The advancement of small, cooled, radial inflow turbine technology in the area of operation at higher turbine inlet temperature is discussed. The first step was accomplished by designing, fabricating, and subjecting to limited mechanical testing an advanced gas generator rotating assembly comprising a radial inflow turbine and two-stage centrifugal compressor. The radial inflow turbine and second-stage compressor were designed as an integrally machined monorotor with turbine cooling taking place basically by conduction to the compressor. Design turbine inlet rotor gas temperature, rotational speed, and overall gas generator compressor pressure ratio were 1422 K (2560 R), 71,222 rpm, and 10/1 respectively. Mechanical testing on a fabricated rotating assembly and bearing system covered 1,000 cold start/stop cycles and three spins to 120 percent design speed (85,466 rpm).

  4. Problems of design and development of advanced superheavy launch vehicles

    NASA Astrophysics Data System (ADS)

    Daniluk, A. Yu.; Klyushnikov, V. Yu.; Kuznetsov, I. I.; Osadchenko, A. S.

    2016-12-01

    The article analyzes problems of design and development of advanced superheavy launch vehicles. Mass and energy characteristics and design layout of launch vehicles are substantiated. Delivery methods of bulky superheavy launch vehicle components to the spacecraft launch site are discussed. Methods of reduction of financial and technical risks of development and operation of superheavy launch vehicles are analyzed. The problem of environmental impacts of superheavy launch vehicle launches is posed.

  5. Advances in design and performance of SHE system components

    NASA Astrophysics Data System (ADS)

    McBride, J. R.; Novak, R. F.; Schmatz, D. J.; Copple, W. B.; Brockway, J. T.

    The sodium heat engine (SHE), a thermoelectric energy conversion device that operates with no moving parts at conversion efficiencies projected to reach 25-30 percent, is discussed. Recent progress in the design and performance of components used in the development of a 1000-W SHE is reported. Advances in long-life electrodes, high-temperature ceramic-to-metal seals, electromagnetic pumps, radiation shields, and current-gathering systems are discussed. Parasitic losses and modular designs are considered.

  6. Advanced Turbine Systems Program: Conceptual design and product development. Quarterly report, February--April 1994

    SciTech Connect

    Benjamin, G.J.

    1994-06-01

    Objective (Phase II) is to develop an industrial gas turbine system to operate at a thermal efficiency of 50% (ATS50) with efficiency enhancements to be added as they become possible. During this quarter, Solar`s engine design team has refined both the 1- and 2-spool cycle concepts, to determine sensitivity to key component efficiencies, cooling air usage and origin, and location of compressor surge lines. The refined analysis included more detailed component work such as compressor and turbine design; different speed trade-offs for the low-and high-pressure compressor in the 1-spool configuration were examined for the best overall compressor efficiency. High-temperature and creep testing of recuperator candidate materials continued. Creep, yield, and proportional limit were measured for foil thicknesses 0.0030--0.0050 for Type 347 ss, Inconel 625, and Haynes 230. Combustor design work included preliminary layout of a multi-can annular combustor integrated into the main engine layout. During the subscale catalytic combustion rig testing, NOx emissions < 5 ppmv were measured. Integration of the engine concept designs into the full power plant system designs has started.

  7. Advanced stratified charge rotary aircraft engine design study

    NASA Technical Reports Server (NTRS)

    Badgley, P.; Berkowitz, M.; Jones, C.; Myers, D.; Norwood, E.; Pratt, W. B.; Ellis, D. R.; Huggins, G.; Mueller, A.; Hembrey, J. H.

    1982-01-01

    A technology base of new developments which offered potential benefits to a general aviation engine was compiled and ranked. Using design approaches selected from the ranked list, conceptual design studies were performed of an advanced and a highly advanced engine sized to provide 186/250 shaft Kw/HP under cruise conditions at 7620/25,000 m/ft altitude. These are turbocharged, direct-injected stratified charge engines intended for commercial introduction in the early 1990's. The engine descriptive data includes tables, curves, and drawings depicting configuration, performance, weights and sizes, heat rejection, ignition and fuel injection system descriptions, maintenance requirements, and scaling data for varying power. An engine-airframe integration study of the resulting engines in advanced airframes was performed on a comparative basis with current production type engines. The results show airplane performance, costs, noise & installation factors. The rotary-engined airplanes display substantial improvements over the baseline, including 30 to 35% lower fuel usage.

  8. Sensing and dynamics of lean blowout in a swirl dump combustor

    NASA Astrophysics Data System (ADS)

    Thiruchengode, Muruganandam

    phenomenon, along with the sensing and control strategies developed in this study could enable the gas turbine combustor designers to design combustors with wider operability regimes. This could have significant payoffs in terms of reduction in NOx emissions from the combustor.

  9. Advanced Fuel Development and Fuel Combustion

    DTIC Science & Technology

    1997-08-01

    operation, and quality control monitoring requirements for these new elements. 39 TASK NO. 26: Surfactant Additives for Improved Low and High...increases are required. Aspen Systems has designed and synthesized a new class of multifunctional additives known as metal deactivating surfactants (MDS... Recycling 4 TASK NO. 03: Emissions Control Through Advanced Combustor Mixing Schemes 5 TASK NO. 04: Gas Layer Protection of Hot Carbon

  10. Advanced EVA system design requirements study, executive summary

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Design requirements and criteria for the space station advanced Extravehicular Activity System (EVAS) including crew enclosures, portable life support systems, maneuvering propulsion systems, and related EVA support equipment were established. The EVA mission requirements, environments, and medical and physiological requirements, as well as operational, procedures and training issues were considered.

  11. Instructional Design Theory: Advancements from Cognitive Science and Instructional Technology.

    ERIC Educational Resources Information Center

    Tennyson, Robert D.

    Scientific advancements in cognitive science and instructional technology extend the behaviorally-oriented learning paradigm of instructional design and management in three major areas: (1) analysis of information-to-be-learned; (2) means of evaluating learners; and (3) linkage of learning theory to instructional prescriptions. The two basic types…

  12. Advanced Jewelry Design. Art Education: 6684.02.

    ERIC Educational Resources Information Center

    Marinaccio, Louis M.

    See SO 007 721 for an introduction to the Visual Arts Education Curriculum of which this course in jewelry design is a part. In the course students further skills in forming complex objects through experience with casting, bezeling stones, and welding. Course content includes an historical perspective on jewelry production and advanced methods in…

  13. Cost and accuracy of advanced breeding trial designs in apple

    PubMed Central

    Harshman, Julia M; Evans, Kate M; Hardner, Craig M

    2016-01-01

    Trialing advanced candidates in tree fruit crops is expensive due to the long-term nature of the planting and labor-intensive evaluations required to make selection decisions. How closely the trait evaluations approximate the true trait value needs balancing with the cost of the program. Designs of field trials of advanced apple candidates in which reduced number of locations, the number of years and the number of harvests per year were modeled to investigate the effect on the cost and accuracy in an operational breeding program. The aim was to find designs that would allow evaluation of the most additional candidates while sacrificing the least accuracy. Critical percentage difference, response to selection, and correlated response were used to examine changes in accuracy of trait evaluations. For the quality traits evaluated, accuracy and response to selection were not substantially reduced for most trial designs. Risk management influences the decision to change trial design, and some designs had greater risk associated with them. Balancing cost and accuracy with risk yields valuable insight into advanced breeding trial design. The methods outlined in this analysis would be well suited to other horticultural crop breeding programs. PMID:27019717

  14. Combustion analysis for flame stability predictions at ground level and altitude in aviation gas turbine engines with low emissions combustors

    NASA Astrophysics Data System (ADS)

    Turek, Tomas

    Low emissions combustors operating with low fuel/air ratios may have challenges with flame stability. As combustion is made leaner in the primary zone, the flame can lose its stability, resulting in operability problems such as relight, flameout or cold starting. This thesis analyzes combustion processes for the prediction of flame stability in low emissions combustors. A detailed review of the literature on flame stability was conducted and main approaches in flame stability modelling were indicated. Three flame stability models were proposed (Characteristic Time, Loading Parameter, and Combustion Efficiency models) and developed into a unique Preliminary Multi-Disciplinary Design Optimization (PMDO) tool. Results were validated with a database of experimental combustor test data and showed that flame stability can be predicted for an arbitrary shape of combustors running at any operational conditions including ground and altitude situations with various jet fuels and nozzles. In conclusion, flame stability can be predicted for newly designed low emission combustors.

  15. Low Emissions RQL Flametube Combustor Component Test Results

    NASA Technical Reports Server (NTRS)

    Holdeman, James D.; Chang, Clarence T.

    2001-01-01

    This report describes and summarizes elements of the High Speed Research (HSR) Low Emissions Rich burn/Quick mix/Lean burn (RQL) flame tube combustor test program. This test program was performed at NASA Glenn Research Center circa 1992. The overall objective of this test program was to demonstrate and evaluate the capability of the RQL combustor concept for High Speed Civil Transport (HSCT) applications with the goal of achieving NOx emission index levels of 5 g/kg-fuel at representative HSCT supersonic cruise conditions. The specific objectives of the tests reported herein were to investigate component performance of the RQL combustor concept for use in the evolution of ultra-low NOx combustor design tools. Test results indicated that the RQL combustor emissions and performance at simulated supersonic cruise conditions were predominantly sensitive to the quick mixer subcomponent performance and not sensitive to fuel injector performance. Test results also indicated the mixing section configuration employing a single row of circular holes was the lowest NOx mixer tested probably due to the initial fast mixing characteristics of this mixing section. However, other quick mix orifice configurations such as the slanted slot mixer produced substantially lower levels of carbon monoxide emissions most likely due to the enhanced circumferential dispersion of the air addition. Test results also suggested that an optimum momentum-flux ratio exists for a given quick mix configuration. This would cause undesirable jet under- or over-penetration for test conditions with momentum-flux ratios below or above the optimum value. Tests conducted to assess the effect of quick mix flow area indicated that reduction in the quick mix flow area produced lower NOx emissions at reduced residence time, but this had no effect on NOx emissions measured at similar residence time for the configurations tested.

  16. Advanced Technology Spark-Ignition Aircraft Piston Engine Design Study

    NASA Technical Reports Server (NTRS)

    Stuckas, K. J.

    1980-01-01

    The advanced technology, spark ignition, aircraft piston engine design study was conducted to determine the improvements that could be made by taking advantage of technology that could reasonably be expected to be made available for an engine intended for production by January 1, 1990. Two engines were proposed to account for levels of technology considered to be moderate risk and high risk. The moderate risk technology engine is a homogeneous charge engine operating on avgas and offers a 40% improvement in transportation efficiency over present designs. The high risk technology engine, with a stratified charge combustion system using kerosene-based jet fuel, projects a 65% improvement in transportation efficiency. Technology enablement program plans are proposed herein to set a timetable for the successful integration of each item of required advanced technology into the engine design.

  17. NASA Project Develops Next-Generation Low-Emissions Combustor Technologies

    NASA Technical Reports Server (NTRS)

    Lee, Chi-Ming; Chang, Clarence T.; Herbon, John T.; Kramer, Stephen K.

    2013-01-01

    NASA's Environmentally Responsible Aviation (ERA) Project is working with industry to develop the fuel flexible combustor technologies for a new generation of low-emissions engine targeted for the 2020 timeframe. These new combustors will reduce nitrogen oxide (NOx) emissions to half of current state-of-the-art (SOA) combustors, while simultaneously reducing noise and fuel burn. The purpose of the low NOx fuel-flexible combustor research is to advance the Technology Readiness Level (TRL) and Integration Readiness Level (IRL) of a low NOx, fuel flexible combustor to the point where it can be integrated in the next generation of aircraft. To reduce project risk and optimize research benefit NASA chose to found two Phase 1 contracts. The first Phase 1 contracts went to engine manufactures and were awarded to: General Electric Company, and Pratt & Whitney Company. The second Phase 1 contracts went to fuel injector manufactures Goodrich Corporation, Parker Hannifin Corporation, and Woodward Fuel System Technology. In 2012, two sector combustors were tested at NASA's ASCR. The results indicated 75% NOx emission reduction below the 2004 CAEP/6 regulation level.

  18. Recent Advances in Power System Design at GSFC

    NASA Technical Reports Server (NTRS)

    Castell, Karen; Wingard, Robert

    1998-01-01

    The recent trends in power system design at NASA's Goddard Space Flight Center (GSFC) have reflected the agency's move toward faster, better and cheaper spacecraft. The demand for a less expensive and standardized spacecraft bus, in addition to a push for accelerated development times has resulted in fewer custom-designed components and more use of commercial off-the-shelf (COTS) products. The more recent power system designs at GSFC have utilized the advances in technology to meet mission requirements while also shrinking weight, volume, cost and development time.

  19. Advanced computational research in materials processing for design and manufacturing

    SciTech Connect

    Zacharia, T.

    1994-12-31

    The computational requirements for design and manufacture of automotive components have seen dramatic increases for producing automobiles with three times the mileage. Automotive component design systems are becoming increasingly reliant on structural analysis requiring both overall larger analysis and more complex analyses, more three-dimensional analyses, larger model sizes, and routine consideration of transient and non-linear effects. Such analyses must be performed rapidly to minimize delays in the design and development process, which drives the need for parallel computing. This paper briefly describes advanced computational research in superplastic forming and automotive crash worthiness.

  20. Advances in Experiment Design for High Performance Aircraft

    NASA Technical Reports Server (NTRS)

    Morelli, Engene A.

    1998-01-01

    A general overview and summary of recent advances in experiment design for high performance aircraft is presented, along with results from flight tests. General theoretical background is included, with some discussion of various approaches to maneuver design. Flight test examples from the F-18 High Alpha Research Vehicle (HARV) are used to illustrate applications of the theory. Input forms are compared using Cramer-Rao bounds for the standard errors of estimated model parameters. Directions for future research in experiment design for high performance aircraft are identified.

  1. The Effect of Air Preheat at Atmospheric Pressure on the Formation of NO(x) in the Quick-Mix Sections of an Axially Staged Combustor

    NASA Technical Reports Server (NTRS)

    Vardakas, M. A.; Leong, M. Y.; Brouwer, J.; Samuelsen, G. S.; Holdeman, J. D.

    1999-01-01

    The Rich-burn/Quick-mix/Lean-burn (RQL) combustor concept has been proposed to minimize the formation of nitrogen oxides (NO(x)) in gas turbine systems. The success of this combustor strategy is dependent upon the efficiency of the mixing section bridging the fuel-rich and fuel-lean stages. Note that although these results were obtained from an experiment designed to study an RQL mixer, the link between mixing and NOx signatures is considerably broader than this application, in that the need to understand this link exists in most advanced combustors. The experiment reported herein was designed to study the effects of inlet air temperature on NO(x) formation in a mixing section. The results indicate that NO(x) emission is increased for all preheated cases compared to non-preheated cases. When comparing the various mixing modules, the affect of jet penetration is important, as this determines where NO(x) concentrations peak, and affects overall NO(x) production. Although jet air comprises 70 percent of the total airflow, the impact that jet air preheat has on overall NO(x) emissions is small compared to preheating both main and jet air flow.

  2. Advanced Control Design for Wind Turbines; Part I: Control Design, Implementation, and Initial Tests

    SciTech Connect

    Wright, A. D.; Fingersh, L. J.

    2008-03-01

    The purpose of this report is to give wind turbine engineers information and examples of the design, testing through simulation, field implementation, and field testing of advanced wind turbine controls.

  3. A variable-geometry combustor used to study primary and secondary zone stoichiometry

    NASA Technical Reports Server (NTRS)

    Briehl, D.; Schultz, D. F.; Ehlers, R. C.

    1983-01-01

    A combustion program is underway to evaluate fuel quality effects on gas turbine combustors. A rich-lean variable geometry combustor design was chosen to evaluate fuel quality effects over a wide range of primary and secondary zone equivalence ratios at simulated engine operating conditions. The first task of this effort, was to evaluate the performance of the variable geometry combustor. The combustor incorporates three stations of variable geometry to control primary and secondary zone equivalence ratio and overall pressure loss. Geometry changes could be made while a test was in progress through the use of remote control actuators. The primary zone liner was water cooled to eliminate the concern of liner durability. Emissions and performance data were obtained at simulated engine conditions of 80 percent and full power. Inlet air temperature varied from 611 to 665K, inlet total pressure varied from 1.02 to 1.24 MPa, reference velocity was a constant 1400 K.

  4. Impacts of broadened-specification fuels on aircraft turbine engine combustors

    SciTech Connect

    Bahr, D.W.

    1982-11-01

    In the future, aircraft turbine engines may be required to accommodate fuels with lower hydrogen contents, fluidity/volatility characteristics, and thermal stability ratings than those of present-day jet fuels. The key results of several investigations conducted to quantify the impacts of such fuel property changes on the performance, pollutant emission, and durability characteristics of aircraft turbine engine combustors are reviewed. These results were obtained in both component and engine tests of the current production combustors used in the CF6-6, CF6-50, F101/CFM56, and J79/CJ805 engines. Based on these results, it is concluded that the most significant concerns associated with such fuel property changes are decreased combustor life, decreased ground starting/altitude relight capabilities, and increased fuel injector gumming/coking tendencies. The combustor design improvements that appear to be needed to permit the use of jet fuels of significantly lower quality than present day fuels are also reviewed.

  5. Induction time effects in pulse combustors

    SciTech Connect

    Bell, J B; Marcus, D L; Pember, R B

    1999-04-09

    Combustion systems that take advantage of a periodic combustion process have many advantages over conventional systems. Their rate of heat transfer is greatly enhanced and their pollutant emissions are lower. They draw in their own supply of fuel and air and they are self-venting. They have few moving parts. The most common type of pulse combustor is based on a Helmholtz resonator - a burning cycle drives a resonant pressure wave, which in turn enhances the rate of combustion, resulting in a self-sustaining, large-scale oscillation. Although the basic physical mechanisms controlling such a process were explained by Rayleigh over a century ago, a full understanding of the operation of a pulse combustor still does not exist. The dominant processes in such a system--combustion, turbulent fluid dynamics, acoustics--are highly coupled and interact nonlinearly, which has reduced the design process to a costly and inefficient trial-and-error procedure. Several recent numerical and experimental studies, however, have been focused towards a better understanding of the basic underlying physics. Barr et al. [l] have elucidated the relative roles of the time scales governing the energy release, the turbulent mixing, and the acoustics. Keller et al. [5] have demonstrated the importance of the phase relation between the resonant pressure field in the tailpipe and the periodic energy release. Marcus et al. [6] have developed the capability for a fully three-dimensional simulation of the reacting flow in a pulse combustor. This paper is an application of that methodology to a detailed investigation of the frequency response of the model to changes in the chemical kinetics. The methodology consists of a fully conservative second-order Godunov algorithm for the inviscid, reacting gas dynamics equations coupled to an adaptive mesh refinement procedure[2]. The axisymmetric and three-dimensional simulations allow us to explore in detail the interaction between the transient fluid

  6. Effect of Surface Impulsive Thermal Loads on Fatigue Behavior of Constant Volume Propulsion Engine Combustor Materials

    NASA Technical Reports Server (NTRS)

    Zhu, Dongming; Fox, Dennis S.; Miller, Robert A.; Ghosn, Louis J.; Kalluri, Sreeramesh

    2004-01-01

    The development of advanced high performance constant-volume-combustion-cycle engines (CVCCE) requires robust design of the engine components that are capable of enduring harsh combustion environments under high frequency thermal and mechanical fatigue conditions. In this study, a simulated engine test rig has been established to evaluate thermal fatigue behavior of a candidate engine combustor material, Haynes 188, under superimposed CO2 laser surface impulsive thermal loads (30 to 100 Hz) in conjunction with the mechanical fatigue loads (10 Hz). The mechanical high cycle fatigue (HCF) testing of some laser pre-exposed specimens has also been conducted under a frequency of 100 Hz to determine the laser surface damage effect. The test results have indicated that material surface oxidation and creep-enhanced fatigue is an important mechanism for the surface crack initiation and propagation under the simulated CVCCE engine conditions.

  7. Analytical fuel property effects, small combustors, phase 1

    NASA Technical Reports Server (NTRS)

    Cohen, J. D.

    1983-01-01

    The effects of nonstandard aviation fuels on a typical small gas turbine combustor was analyzed. The T700/CT7 engine family was chosen as being representative of the class of aircraft power plants desired. Fuel properties, as specified by NASA, are characterized by low hydrogen content and high aromatics levels. Higher than normal smoke output and flame radiation intensity for the current T700 combustor which serves as a baseline were anticipated. It is, therefore, predicted that out of specification smoke visibility and higher than normal shell temperatures will exist when using NASA ERBS fuels with a consequence of severe reduction in cyclic life. Three new designs are proposed to compensate for the deficiencies expected with the existing design. They have emerged as the best of the eight originally proposed redesigns or combinations thereof. After the five choices that were originally made by NASA on the basis of competing performance factors, General Electric narrowed the field to the three proposed.

  8. Conceptual model of turbulent flameholding for scramjet combustors

    NASA Technical Reports Server (NTRS)

    Huber, P. W.

    1980-01-01

    New concepts and approaches to scramjet combustor design are presented. Blowoff was from failure of the recirculation-zone (RZ) flame to reach the dividing streamline (DS) at the rear stagnation zone. Increased turbulent exchange across the DS helped flameholding due to forward movement of the flame anchor point inside the RZ. Modeling of the blowoff phenomenon was based on a mass conservation concept involving the traverse of a flame element across the RZ and a flow element along the DS. The scale required to achieve flameholding, predicted by the model, showed a strong adverse effect of low pressure and low fuel equivalence ratio, moderate effect of flight Mach number, and little effect of temperature recovery factor. Possible effects of finite rate chemistry on flameholding and flamespreading in scramjets are discussed and recommendations for approaches to engine combustor design as well as for needed research to reduce uncertainties in the concepts are made.

  9. Numerical Study of Low Emission Gas Turbine Combustor Concepts

    NASA Technical Reports Server (NTRS)

    Yang, Song-Lin

    2002-01-01

    To further reduce pollutant emissions, such as CO, NO(x), UHCs, etc., in the next few decades, innovative concepts of gas turbine combustors must be developed. Several concepts, such as the LIPP (Lean- Premixed- Prevaporized), RQL (Rich-Burn Quick-Quench Lean-Burn), and LDI (Lean-Direct-Injection), have been under study for many years. To fully realize the potential of these concepts, several improvements, such as inlet geometry, air swirler, aerothermochemistry control, fuel preparation, fuel injection and injector design, etc., must be made, which can be studied through the experimental method and/or the numerical technique. The purpose of this proposal is to use the CFD technique to study, and hence, to guide the design process for low emission gas turbine combustors. A total of 13 technical papers have been (or will be) published.

  10. Combustor with non-circular head end

    DOEpatents

    Kim, Won -Wook; McMahan, Kevin Weston

    2015-09-29

    The present application provides a combustor for use with a gas turbine engine. The combustor may include a head end with a non-circular configuration, a number of fuel nozzles positioned about the head end, and a transition piece extending downstream of the head end.

  11. Design of the advanced regional aircraft, the DART-75

    NASA Technical Reports Server (NTRS)

    Elliot, Steve; Gislason, Jason; Huffstetler, Mark; Mann, Jon; Withers, Ashley; Zimmerman, Mark

    1992-01-01

    The need for regional aircraft stems from the problem of hub airport congestion. Regional travel will allow a passenger to commute from one spoke city to another spoke city without entering the congested hub airport. In addition, those people traveling longer routes may begin the flight at home instead of traveling to the hub airport. At this time, there is no American aerospace company that produces a regional transport for under 100 passengers. The intention of the Developmental Advanced Regional Transport (DART-75) is to fill this void with a modern, efficient regional aircraft. This design achieves the efficiency through a number of advanced features including three lifting surfaces, partial composite construction, and an advanced engine design. Efficiency is not the only consideration. Structural integrity, fatigue life, ease of maintenance, passenger comfort and convenience, and environmental aspects must all be considered. These factors force the design team to face many tradeoffs that are studied to find the best solution. The final consideration that cannot be overlooked is that of cost. The DART-75 is a 75-passenger medium-range regional transport intended for spoke-to-spoke, spoke-to-hub, and some hub-to-hub operations. Included are the general descriptions of the structures, weight and balance, stability and control, performance, and engine design.

  12. Development of environmentally advanced hydropower turbine system design concepts

    SciTech Connect

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

    1997-08-01

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

  13. Advanced Subsonic Combustion Rig

    NASA Technical Reports Server (NTRS)

    Lee, Chi-Ming

    1998-01-01

    Researchers from the NASA Lewis Research Center have obtained the first combustion/emissions data under extreme future engine operating conditions. In Lewis' new world-class 60-atm combustor research facility--the Advanced Subsonic Combustion Rig (ASCR)--a flametube was used to conduct combustion experiments in environments as extreme as 900 psia and 3400 F. The greatest challenge for combustion researchers is the uncertainty of the effects of pressure on the formation of nitrogen oxides (NOx). Consequently, U.S. engine manufacturers are using these data to guide their future combustor designs. The flametube's metal housing has an inside diameter of 12 in. and a length of 10.5 in. The flametube can be used with a variety of different flow paths. Each flow path is lined with a high-temperature, castable refractory material (alumina) to minimize heat loss. Upstream of the flametube is the injector section, which has an inside diameter of 13 in. and a length of 0.5-in. It was designed to provide for quick changeovers. This flametube is being used to provide all U.S. engine manufacturers early assessments of advanced combustion concepts at full power conditions prior to engine production. To date, seven concepts from engine manufacturers have been evaluated and improved. This collaborated development can potentially give U.S. engine manufacturers the competitive advantage of being first in the market with advanced low-emission technologies.

  14. Advanced Electric Submersible Pump Design Tool for Geothermal Applications

    SciTech Connect

    Xuele Qi; Norman Turnquist; Farshad Ghasripoor

    2012-05-31

    Electrical Submersible Pumps (ESPs) present higher efficiency, larger production rate, and can be operated in deeper wells than the other geothermal artificial lifting systems. Enhanced Geothermal Systems (EGS) applications recommend lifting 300 C geothermal water at 80kg/s flow rate in a maximum 10-5/8-inch diameter wellbore to improve the cost-effectiveness. In this paper, an advanced ESP design tool comprising a 1D theoretical model and a 3D CFD analysis has been developed to design ESPs for geothermal applications. Design of Experiments was also performed to optimize the geometry and performance. The designed mixed-flow type centrifugal impeller and diffuser exhibit high efficiency and head rise under simulated EGS conditions. The design tool has been validated by comparing the prediction to experimental data of an existing ESP product.

  15. Experimental clean combustor program, phase 3

    NASA Technical Reports Server (NTRS)

    Roberts, R.; Fiorentino, A.; Greene, W.

    1977-01-01

    A two-stage vortex burning and mixing combustor and associated fuel system components were successfully tested at steady state and transient operating conditions. The combustor exceeded the program goals for all three emissions species, with oxides of nitrogen 10 percent below the goal, carbon monoxide 26 percent below the goal, and total unburned hydrocarbons 75 percent below the goal. Relative to the JT9D-7 combustor, the oxides of nitrogen were reduced by 58 percent, carbon monoxide emissions were reduced by 69 percent, and total unburned hydrocarbons were reduced by 9 percent. The combustor efficiency and exit temperature profiles were comparable to those of production combustor. Acceleration and starting characteristics were deficient relative to the production engine.

  16. Laser Diagnostic Development and Measurement and Modeling of Turbulent Flowfields of Jets and Wakes. Part 2. Numerical Predictions of Isothermal Flowfields in a Ducted Centerbody Combustor.

    DTIC Science & Technology

    1983-06-01

    objectives: (a) providing profile data that can be used to evaluate combustor and fuel combustion ’iodels and (bo) evaluating the performance of...combustor models and dif- ferent diagnostic technicrues in various combustion enviro)nments. The technical efforts dealing with the design and develop...centerbody combustor of roughly 1/5-scale model of the APL configuration at the Combustion Laboratory of the University of California, Irvine (UCI). 2 1

  17. Advanced Free Flight Planner and Dispatcher's Workstation: Preliminary Design Specification

    NASA Technical Reports Server (NTRS)

    Wilson, J.; Wright, C.; Couluris, G. J.

    1997-01-01

    The National Aeronautics and Space Administration (NASA) has implemented the Advanced Air Transportation Technology (AATT) program to investigate future improvements to the national and international air traffic management systems. This research, as part of the AATT program, developed preliminary design requirements for an advanced Airline Operations Control (AOC) dispatcher's workstation, with emphasis on flight planning. This design will support the implementation of an experimental workstation in NASA laboratories that would emulate AOC dispatch operations. The work developed an airline flight plan data base and specified requirements for: a computer tool for generation and evaluation of free flight, user preferred trajectories (UPT); the kernel of an advanced flight planning system to be incorporated into the UPT-generation tool; and an AOC workstation to house the UPT-generation tool and to provide a real-time testing environment. A prototype for the advanced flight plan optimization kernel was developed and demonstrated. The flight planner uses dynamic programming to search a four-dimensional wind and temperature grid to identify the optimal route, altitude and speed for successive segments of a flight. An iterative process is employed in which a series of trajectories are successively refined until the LTPT is identified. The flight planner is designed to function in the current operational environment as well as in free flight. The free flight environment would enable greater flexibility in UPT selection based on alleviation of current procedural constraints. The prototype also takes advantage of advanced computer processing capabilities to implement more powerful optimization routines than would be possible with older computer systems.

  18. Combustor for fine particulate coal

    DOEpatents

    Carlson, L.W.

    1988-01-26

    A particulate coal combustor with two combustion chambers is provided. The first combustion chamber is toroidal; air and fuel are injected, mixed, circulated and partially combusted. The air to fuel ratio is controlled to avoid production of soot or nitrogen oxides. The mixture is then moved to a second combustion chamber by injection of additional air where combustion is completed and ash removed. Temperature in the second chamber is controlled by cooling and gas mixing. The clean stream of hot gas is then delivered to a prime mover. 4 figs.

  19. Combustor for fine particulate coal

    DOEpatents

    Carlson, L.W.

    1988-11-08

    A particulate coal combustor with two combustion chambers is provided. The first combustion chamber is toroidal; air and fuel are injected, mixed, circulated and partially combusted. The air to fuel ratio is controlled to avoid production of soot or nitrogen oxides. The mixture is then moved to a second combustion chamber by injection of additional air where combustion is completed and ash removed. Temperature in the second chamber is controlled by cooling and gas mixing. The clean stream of hot gas is then delivered to a prime mover. 4 figs.

  20. Combustor for fine particulate coal

    DOEpatents

    Carlson, Larry W.

    1988-01-01

    A particulate coal combustor with two combustion chambers is provided. The first combustion chamber is toroidal; air and fuel are injected, mixed, circulated and partially combusted. The air to fuel ratio is controlled to avoid production of soot or nitrogen oxides. The mixture is then moved to a second combustion chamber by injection of additional air where combustion is completed and ash removed. Temperature in the second chamber is controlled by cooling and gas mixing. The clean stream of hot gas is then delivered to a prime mover.

  1. Advanced coal-fueled gas turbine systems reference system definition update

    SciTech Connect

    Not Available

    1991-09-01

    The objective of the the Direct Coal-Fueled 80 MW Combustion Turbine Program is to establish the technology required for private sector use of an advanced coal-fueled combustion turbine power system. Under this program the technology for a direct coal-fueled 80 MW combustion turbine is to be developed. This unit would be an element in a 207 MW direct coal-fueled combustion turbine combined cycle which includes two combustion turbines, two heat recovery steam generators and a steam turbine. Key to meeting the program objectives is the development of a successful high pressure slagging combustor that burns coal, while removing sulfur, particulates, and corrosive alkali matter from the combustion products. Westinghouse and Textron (formerly AVCO Research Laboratory/Textron) have designed and fabricated a subscale slagging combustor. This slagging combustor, under test since September 1988, has been yielding important experimental data, while having undergone several design iterations.

  2. Development of a retrofit coal combustor for industrial applications, (Phase 1-A)

    SciTech Connect

    Not Available

    1988-10-01

    During this past quarter, two tandem-fired pulse combustors were designed to fire at a nominal rate of 3.5 to 5.5 MMBtu/hr under continuation of Phase I work on DOE project DE-AC22-87PC79654. In prior work, MTCI demonstrated the operation of a 1--2 MMBtu/h coal-fired tandem pulse combustor that is intended for small industrial applications. These component tests emphasized verification of key design issues such as combustor coupling, slag rejection, and staged air addition. The current work, which represents an extension of the Phase I effort, focuses on integrated testing of the tandem pulse combustor with a fire-tube boiler, and the addition of a slag quench vessel. A tandem-fired pulse combustion unit designed to fire at a nominal rate of 3.5-5 MMBtu/hr was designed and fabricated. The configuration includes two combustion chambers cast in a single monolith, tailpipes cast separately with annular air preheating capability, and a cyclonic decoupler. Design analysis and evaluations were performed to optimize the system with respect to minimizing heat losses, size, and cost. Heat losses from the combustor and decoupler walls are predicted to be approximately 3 percent. The final designs for the ancillary items (slag quench, tertiary air addition, scrubber and sampling system) were completed and fabrication and installation initiated. A Cleaver-Brooks 150 hp-4 pass boiler was delivered and installed and modifications for interfacing with the retrofit pulse combustor unit completed. A below-ground slag collection pit was excavated to permit direct in-line coupling of the combustor to the boiler and to reduce head-room requirements. The pit is 30 inches deep and lined with waterproof and fireproof siding.

  3. Advanced composites: Design and application. Proceedings of the meeting of the Mechanical Failures Prevention Group

    NASA Technical Reports Server (NTRS)

    Shives, T. R.; Willard, W. A.

    1979-01-01

    The design and application of advanced composites is discussed with emphasis on aerospace, aircraft, automotive, marine, and industrial applications. Failure modes in advanced composites are also discussed.

  4. Soft computing in design and manufacturing of advanced materials

    NASA Technical Reports Server (NTRS)

    Cios, Krzysztof J.; Baaklini, George Y; Vary, Alex

    1993-01-01

    The potential of fuzzy sets and neural networks, often referred to as soft computing, for aiding in all aspects of manufacturing of advanced materials like ceramics is addressed. In design and manufacturing of advanced materials, it is desirable to find which of the many processing variables contribute most to the desired properties of the material. There is also interest in real time quality control of parameters that govern material properties during processing stages. The concepts of fuzzy sets and neural networks are briefly introduced and it is shown how they can be used in the design and manufacturing processes. These two computational methods are alternatives to other methods such as the Taguchi method. The two methods are demonstrated by using data collected at NASA Lewis Research Center. Future research directions are also discussed.

  5. Design of an advanced 500-HP helicopter transmission

    NASA Technical Reports Server (NTRS)

    Braddock, C. E.

    1982-01-01

    A 500-hp Advanced Technology Demonstrator helicopter transmission was designed by an American aerospace company under a NASA contract. The project was mainly concerned with designing a 500-hp version of the OH-58C 317-hp transmission which would have the capabilities for a long, quiet life at a minimum increase in cost, weight, and space, which usually increase along with power increases. This objective was accomplished by implementing advanced technology which has been developed during the last decade and by making improvements dictated by field experience. The improvements are related to bearings made of cleaner gear steels, spiral bevel gears made of cleaner gear steels, high contact ratio spur gear teeth in the planetary which will reduce noise level and increase gear life, and modifications concerning the sun gear.

  6. Conceptual design study: Forest Fire Advanced System Technology (FFAST)

    NASA Technical Reports Server (NTRS)

    Nichols, J. D.; Warren, J. R.

    1986-01-01

    An integrated forest fire detection and mapping system that will be based upon technology available in the 1990s was defined. Uncertainties in emerging and advanced technologies related to the conceptual design were identified and recommended for inclusion as preferred system components. System component technologies identified for an end-to-end system include thermal infrared, linear array detectors, automatic georeferencing and signal processing, geosynchronous satellite communication links, and advanced data integration and display. Potential system configuration options were developed and examined for possible inclusion in the preferred system configuration. The preferred system configuration will provide increased performance and be cost effective over the system currently in use. Forest fire management user requirements and the system component emerging technologies were the basis for the system configuration design. A preferred system configuration was defined that warrants continued refinement and development, examined economic aspects of the current and preferred system, and provided preliminary cost estimates for follow-on system prototype development.

  7. AGBT Advanced Counter-Rotating Gearbox Detailed Design Report

    NASA Technical Reports Server (NTRS)

    Howe, D. C.; Sundt, C. V.; Mckibbon, A. H.

    1988-01-01

    An Advanced Counter-Rotating (CR) Gearbox was designed and fabricated to evaluate gearbox efficiency, durability and weight characteristics for emerging propfan-powered airplanes. Component scavenge tests showed that a constant volume collector had high scavenge effectiveness, which was uneffected by added airflow. Lubrication tests showed that gearbox losses could be reduced by controlling the air/oil mixture and by directing the oil jets radially, with a slight axial component, into the sun/planet gears.

  8. Test model designs for advanced refractory ceramic materials

    NASA Technical Reports Server (NTRS)

    Tran, Huy Kim

    1993-01-01

    The next generation of space vehicles will be subjected to severe aerothermal loads and will require an improved thermal protection system (TPS) and other advanced vehicle components. In order to ensure the satisfactory performance system (TPS) and other advanced vehicle materials and components, testing is to be performed in environments similar to space flight. The design and fabrication of the test models should be fairly simple but still accomplish test objectives. In the Advanced Refractory Ceramic Materials test series, the models and model holders will need to withstand the required heat fluxes of 340 to 817 W/sq cm or surface temperatures in the range of 2700 K to 3000 K. The model holders should provide one dimensional (1-D) heat transfer to the samples and the appropriate flow field without compromising the primary test objectives. The optical properties such as the effective emissivity, catalytic efficiency coefficients, thermal properties, and mass loss measurements are also taken into consideration in the design process. Therefore, it is the intent of this paper to demonstrate the design schemes for different models and model holders that would accommodate these test requirements and ensure the safe operation in a typical arc jet facility.

  9. Advanced 3D inverse method for designing turbomachine blades

    SciTech Connect

    Dang, T.

    1995-10-01

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

  10. Design of an AdvancedTCA board management controller (IPMC)

    NASA Astrophysics Data System (ADS)

    Mendez, J.; Bobillier, V.; Haas, S.; Joos, M.; Mico, S.; Vasey, F.

    2017-03-01

    The AdvancedTCA (ATCA) standard has been selected as the hardware platform for the upgrade of the back-end electronics of the CMS and ATLAS experiments of the Large Hadron Collider (LHC) . In this context, the electronic systems for experiments group at CERN is running a project to evaluate, specify, design and support xTCA equipment. As part of this project, an Intelligent Platform Management Controller (IPMC) for ATCA blades, based on a commercial solution, has been designed to be used on existing and future ATCA blades. This paper reports on the status of this project presenting the hardware and software developments.

  11. VVANTAGE 6 - an advanced fuel assembly design for VVER reactors

    SciTech Connect

    Doshi, P.K.; DeMario, E.E.; Knott, R.P.

    1993-12-31

    Over the last 25 years, Westinghouse fuel assemblies for pressurized water reactors (PWR`s) have undergone significant changes to the current VANTAGE 5. VANTAGE 5 PWR fuel includes features such as removable top nozzles, debris filter bottom nozzles, low-pressure-drop zircaloy grids, zircaloy intermediate flow mixing grids, optimized fuel rods, in-fuel burnable absorbers, and increased burnup capability to region average values of 48000 MWD/MTU. These features have now been adopted to the VVER reactors. Westinghouse has completed conceptual designs for an advanced fuel assembly and other core components for VVER-1000 reactors known as VANTAGE 6. This report describes the VVANTAGE 6 fuel assembly design.

  12. Advanced Sensor Fish Device for ImprovedTurbine Design

    SciTech Connect

    Carlson, Thomas J.

    2009-09-14

    Juvenile salmon (smolts) passing through hydroelectric turbines are subjected to environmental conditions that can potentially kill or injure them. Many turbines are reaching the end of their operational life expectancies and will be replaced with new turbines that incorporate advanced “fish friendly” designs devised to prevent injury and death to fish. To design a fish friendly turbine, it is first necessary to define the current conditions fish encounter. One such device used by biologists at Pacific Northwest National Laboratory was the sensor fish device to collect data that measures the forces fish experience during passage through hydroelectric projects.

  13. A new unsteady mixing model to predict NO(x) production during rapid mixing in a dual-stage combustor

    NASA Technical Reports Server (NTRS)

    Menon, Suresh

    1992-01-01

    An advanced gas turbine engine to power supersonic transport aircraft is currently under study. In addition to high combustion efficiency requirements, environmental concerns have placed stringent restrictions on the pollutant emissions from these engines. A combustor design with the potential for minimizing pollutants such as NO(x) emissions is undergoing experimental evaluation. A major technical issue in the design of this combustor is how to rapidly mix the hot, fuel-rich primary zone product with the secondary diluent air to obtain a fuel-lean mixture for combustion in the second stage. Numerical predictions using steady-state methods cannot account for the unsteady phenomena in the mixing region. Therefore, to evaluate the effect of unsteady mixing and combustion processes, a novel unsteady mixing model is demonstrated here. This model has been used to study multispecies mixing as well as propane-air and hydrogen-air jet nonpremixed flames, and has been used to predict NO(x) production in the mixing region. Comparison with available experimental data show good agreement, thereby providing validation of the mixing model. With this demonstration, this mixing model is ready to be implemented in conjunction with steady-state prediction methods and provide an improved engineering design analysis tool.

  14. Rich burn combustor technology at Pratt and Whitney

    NASA Technical Reports Server (NTRS)

    Lohmann, Robert P.; Rosfjord, T. J.

    1992-01-01

    The topics covered include the following: near term objectives; rich burn quick quench combustor (RBQC); RBQC critical technology areas; cylindrical RBQQ combustor rig; modular RBQQ combustor; cylindrical rig objectives; quench zone mixing; noneffusive cooled liner; variable geometry requirements; and sector combustor rig.

  15. The advanced PFB process: Pilot plant results and design studies

    SciTech Connect

    Robertson, A.; Domeracki, W.; Horazak, D.; Rehmat, A.

    1993-11-01

    The plant being developed is a hybrid of two technologies; it incorporates the partial gasification of coal in a vessel called the carbonizer and the combustion of the resultant char residue in a circulating pressurized fluidized bed combustor (CPFBC). In this plant, coal is fed to a pressurized carbonizer that produces a low-Btu fuel gas and char. After passing through a cyclone and a ceramic barrier filter to remove gas-entrained particulates, the fuel gas is burned in a topping combustor to produce the energy required to drive a gas turbine. The gas turbine drives a generator and a compressor that feeds air to the carbonizer, a CPFBC, and a fluidized bed heat exchanger (FBHE). The carbonizer char is burned in the CPFBC with high excess air. The vitiated air from the CPFBC supports combustion of the fuel gas in the gas turbine topping combustor. Steam generated in a heat-recovery steam generator (HRSG) downstream of the gas turbine and in the FBHE associated with the CPFBC drives the steam turbine generator that furnishes the balance of electric power delivered by the plant. The low-Btu gas is produced in the carbonizer by pyrolysis/mild devolatilization of coal in a fluidized bed reactor. Because this unit operates at temperatures much lower than gasifiers currently under development, it also produces a char residue. Left untreated, the fuel gas will contain hydrogen sulfide and sulfur-containing tar/light oil vapors; therefore, lime-based sorbents are injected into the carbonizer to catalytically enhance tar cracking and to capture sulfur as calcium sulfide. Sulfur is captured in situ, and the raw fuel gas is fired hot. Thus the expensive, complex, fuel gas heat exchangers and the chemical or sulfur-capturing bed cleanup systems that are part of the coal gasification combined-cycle plants now being developed are eliminated.

  16. Advanced designs for IPV nickel-hydrogen cells

    NASA Technical Reports Server (NTRS)

    Smithrick, J. J.; Manzo, M. A.; Gonzalez-Sanabria, O. D.

    1984-01-01

    Advanced designs for individual pressure vessel nickel-hydrogen cells have been concieved which should improve the cycle life at deep depths-of-discharge. Features of the designs which are new and not incorporated in either of the contemporary cells (Air Force/Hughes, Comsat) are: (1) use of alternate methods of oxygen recombination, (2) use of serrated edge separators to facilitate movement of gas within the cell while still maintaining required physical contact with the wall wick, and (3) use of an expandable stack to accommodate some of the nickel electrode expansion. The designs also consider electrolyte volume requirements over the life of the cells, and are fully compatible with the Air Force/Hughes design.

  17. Preliminary design study of advanced multistage axial flow core compressors

    NASA Technical Reports Server (NTRS)

    Wisler, D. C.; Koch, C. C.; Smith, L. H., Jr.

    1977-01-01

    A preliminary design study was conducted to identify an advanced core compressor for use in new high-bypass-ratio turbofan engines to be introduced into commercial service in the 1980's. An evaluation of anticipated compressor and related component 1985 state-of-the-art technology was conducted. A parametric screening study covering a large number of compressor designs was conducted to determine the influence of the major compressor design features on efficiency, weight, cost, blade life, aircraft direct operating cost, and fuel usage. The trends observed in the parametric screening study were used to develop three high-efficiency, high-economic-payoff compressor designs. These three compressors were studied in greater detail to better evaluate their aerodynamic and mechanical feasibility.

  18. Aerodynamic Design Study of an Advanced Active Twist Rotor

    NASA Technical Reports Server (NTRS)

    Sekula, Martin K.; Wilbur, Matthew L.; Yeager, William T., Jr.

    2003-01-01

    An Advanced Active Twist Rotor (AATR) is currently being developed by the U.S. Army Vehicle Technology Directorate at NASA Langley Research Center. As a part of this effort, an analytical study was conducted to determine the impact of blade geometry on active-twist performance and, based on those findings, propose a candidate aerodynamic design for the AATR. The process began by creating a baseline design which combined the dynamic design of the original Active Twist Rotor and the aerodynamic design of a high lift rotor concept. The baseline model was used to conduct a series of parametric studies to examine the effect of linear blade twist and blade tip sweep, droop, and taper on active-twist performance. Rotor power requirements and hub vibration were also examined at flight conditions ranging from hover to advance ratio = 0.40. A total of 108 candidate designs were analyzed using the second-generation version of the Comprehensive Analytical Model of Rotorcraft Aerodynamics and Dynamics (CAMRAD II) code. The study concluded that the vibration reduction capabilities of a rotor utilizing controlled, strain-induced twisting are enhanced through the incorporation of blade tip sweep, droop, and taper into the blade design, while they are degraded by increasing the nose-down linear blade twist. Based on the analysis of rotor power, hub vibration, and active-twist response, a candidate aerodynamic design for the AATR consisting of a blade with approximately 10 degrees of linear blade twist and a blade tip design with 30 degree sweep, 10 degree droop, and 2.5:1 taper ratio over the outer five percent of the blade is proposed.

  19. Wedge edge ceramic combustor tile

    DOEpatents

    Shaffer, J.E.; Holsapple, A.C.

    1997-06-10

    A multipiece combustor has a portion thereof being made of a plurality of ceramic segments. Each of the plurality of ceramic segments have an outer surface and an inner surface. Each of the plurality of ceramic segments have a generally cylindrical configuration and including a plurality of joints. The joints define joint portions, a first portion defining a surface being skewed to the outer surface and the inner surface. The joint portions have a second portion defining a surface being skewed to the outer surface and the inner surface. The joint portions further include a shoulder formed intermediate the first portion and the second portion. The joints provide a sealing interlocking joint between corresponding ones of the plurality of ceramic segments. Thus, the multipiece combustor having the plurality of ceramic segment with the plurality of joints reduces the physical size of the individual components and the degradation of the surface of the ceramic components in a tensile stress zone is generally eliminated reducing the possibility of catastrophic failures. 7 figs.

  20. Wedge edge ceramic combustor tile

    DOEpatents

    Shaffer, James E.; Holsapple, Allan C.

    1997-01-01

    A multipiece combustor has a portion thereof being made of a plurality of ceramic segments. Each of the plurality of ceramic segments have an outer surface and an inner surface. Each of the plurality of ceramic segments have a generally cylindrical configuration and including a plurality of joints. The joints define joint portions, a first portion defining a surface being skewed to the outer surface and the inner surface. The joint portions have a second portion defining a surface being skewed to the outer surface and the inner surface. The joint portions further include a shoulder formed intermediate the first portion and the second portion. The joints provide a sealing interlocking joint between corresponding ones of the plurality of ceramic segments. Thus, the multipiece combustor having the plurality of ceramic segment with the plurality of joints reduces the physical size of the individual components and the degradation of the surface of the ceramic components in a tensile stress zone is generally eliminated reducing the possibility of catastrophic failures.

  1. A Unique, Optically Accessible Flame Tube Facility for Lean Combustor Studies

    NASA Technical Reports Server (NTRS)

    Hicks, Yolanda R.; Locke, Randy J.; Wey, Chowen C.; Bianco, Jean

    1995-01-01

    A facility that allows interrogation of combusting flows by advanced diagnostic methods and instrumentation has been developed at the NASA Lewis Research Center. An optically accessible flame tube combustor is described which has high temperature, pressure, and air flow capabilities. The windows in the combustor measure 3.8 cm axially by 5.1 cm radially, providing 67% optical access to the 7.6 cm x 7.6 cm cross section flow chamber. Advanced gas analysis instrumentation is available through a gas chromatography/mass spectrometer system (GC/MS), which has on-line capability for heavy hydrocarbon measurement with resolution to the parts per billion level. The instrumentation allows one to study combusting flows and combustor subcomponents, such as fuel injectors and air swirlers. Planar Laser Induced Fluorescence (PLIF) can measure unstable combustion species, which cannot be obtained with traditional gas sampling. This type of data is especially useful to combustion modellers. The optical access allows measurements to have high spatial and temporal resolution. GC/MS data and PLIF images of OH- are presented from experiments using a lean direct injection (LDI) combustor burning Jet-A fuel at inlet temperatures ranging from 810 K to 866 K, combustor pressures up to 1380 kPa, and equivalence ratios from 0.41 to 0.59.

  2. Driving of combustor oscillations by gaseous propellant injectors

    NASA Technical Reports Server (NTRS)

    Janardan, B. A.; Daniel, B. R.; Zinn, B. T.

    1979-01-01

    Measurements of reactive admittances that describe the capabilities of the combustion processes associated with coaxial gaseous fuel injectors to amplify combustor oscillations are presented. These admittances are needed in (1) stability analyses of rocket motors and gas turbine combustors; (2) for the evaluation of 'driving' capabilities of injectors; and (3) for checking the applicability of a theoretical model. The modified standing-wave technique was used to determine the admittances of the combustion processes in coaxial injectors utilizing air-acetylene mixtures. The measurements indicated that (1) coaxial injectors can sustain combustion instabilities over wide frequency ranges; (2) the maximum driving capability of an injector decreases with an increased equivalence ratio; (3) the frequency at which maximum driving is observed decreases with the increased equivalence ratio; and (4) the characteristic combustion time of an injector design decreases with increased frequency.

  3. Cars Thermometry in a Supersonic Combustor for CFD Code Validation

    NASA Technical Reports Server (NTRS)

    Cutler, A. D.; Danehy, P. M.; Springer, R. R.; DeLoach, R.; Capriotti, D. P.

    2002-01-01

    An experiment has been conducted to acquire data for the validation of computational fluid dynamics (CFD) codes used in the design of supersonic combustors. The primary measurement technique is coherent anti-Stokes Raman spectroscopy (CARS), although surface pressures and temperatures have also been acquired. Modern- design- of-experiment techniques have been used to maximize the quality of the data set (for the given level of effort) and minimize systematic errors. The combustor consists of a diverging duct with single downstream- angled wall injector. Nominal entrance Mach number is 2 and enthalpy nominally corresponds to Mach 7 flight. Temperature maps are obtained at several planes in the flow for two cases: in one case the combustor is piloted by injecting fuel upstream of the main injector, the second is not. Boundary conditions and uncertainties are adequately characterized. Accurate CFD calculation of the flow will ultimately require accurate modeling of the chemical kinetics and turbulence-chemistry interactions as well as accurate modeling of the turbulent mixing

  4. Update on quadruple suspension design for Advanced LIGO

    NASA Astrophysics Data System (ADS)

    Aston, S. M.; Barton, M. A.; Bell, A. S.; Beveridge, N.; Bland, B.; Brummitt, A. J.; Cagnoli, G.; Cantley, C. A.; Carbone, L.; Cumming, A. V.; Cunningham, L.; Cutler, R. M.; Greenhalgh, R. J. S.; Hammond, G. D.; Haughian, K.; Hayler, T. M.; Heptonstall, A.; Heefner, J.; Hoyland, D.; Hough, J.; Jones, R.; Kissel, J. S.; Kumar, R.; Lockerbie, N. A.; Lodhia, D.; Martin, I. W.; Murray, P. G.; O'Dell, J.; Plissi, M. V.; Reid, S.; Romie, J.; Robertson, N. A.; Rowan, S.; Shapiro, B.; Speake, C. C.; Strain, K. A.; Tokmakov, K. V.; Torrie, C.; van Veggel, A. A.; Vecchio, A.; Wilmut, I.

    2012-12-01

    We describe the design of the suspension systems for the major optics for Advanced LIGO, the upgrade to LIGO—the Laser Interferometric Gravitational-Wave Observatory. The design is based on that used in GEO600—the German/UK interferometric gravitational wave detector, with further development to meet the more stringent noise requirements for Advanced LIGO. The test mass suspensions consist of a four-stage or quadruple pendulum for enhanced seismic isolation. To minimize suspension thermal noise, the final stage consists of a silica mirror, 40 kg in mass, suspended from another silica mass by four silica fibres welded to silica ears attached to the sides of the masses using hydroxide-catalysis bonding. The design is chosen to achieve a displacement noise level for each of the seismic and thermal noise contributions of 10-19 m/√Hz at 10 Hz, for each test mass. We discuss features of the design which has been developed as a result of experience with prototypes and associated investigations.

  5. Parametric Modeling Investigation of a Radially-Staged Low-Emission Aviation Combustor

    NASA Technical Reports Server (NTRS)

    Heath, Christopher M.

    2016-01-01

    Aviation gas-turbine combustion demands high efficiency, wide operability and minimal trace gas emissions. Performance critical design parameters include injector geometry, combustor layout, fuel-air mixing and engine cycle conditions. The present investigation explores these factors and their impact on a radially staged low-emission aviation combustor sized for a next-generation 24,000-lbf-thrust engine. By coupling multi-fidelity computational tools, a design exploration was performed using a parameterized annular combustor sector at projected 100% takeoff power conditions. Design objectives included nitrogen oxide emission indices and overall combustor pressure loss. From the design space, an optimal configuration was selected and simulated at 7.1, 30 and 85% part-power operation, corresponding to landing-takeoff cycle idle, approach and climb segments. All results were obtained by solution of the steady-state Reynolds-averaged Navier-Stokes equations. Species concentrations were solved directly using a reduced 19-step reaction mechanism for Jet-A. Turbulence closure was obtained using a nonlinear K-epsilon model. This research demonstrates revolutionary combustor design exploration enabled by multi-fidelity physics-based simulation.

  6. Advanced Low-Noise Research Fan Stage Design

    NASA Technical Reports Server (NTRS)

    Neubert, Robert; Bock, Larry; Malmborg, Eric; Owen-Peer, William

    1997-01-01

    This report describes the design of the Advanced Low-Noise Research Fan stage. The fan is a variable pitch design, which is designed at the cruise pitch condition. Relative to the cruise setting, the blade is closed at takeoff and opened for reverse thrust operation. The fan stage is a split flow design with fan exit guide vanes (FEGVs) and core stators. The fan stage design is combined with a nacelle and engine core duct to form a powered fan/nacelle subscale model. This model is intended for use in combined aerodynamic, acoustic, and structural testing in a wind tunnel. The fan has an outer diameter of 22 in. and a hub-to-tip of 0.426 in., which allows the use of existing NASA fan and cowl force balance and rig drive systems. The design parameters were selected to permit valid acoustic and aerodynamic comparisons with the Pratt & Whitney (P&W) 17- and 22-in. rigs previously tested under NASA contract. The fan stage design is described in detail. The results of the design axisymmetric and Navier-Stokes aerodynamic analysis are presented at the critical design conditions. The structural analysis of the fan rotor and attachment is included. The blade and attachment are predicted to have adequate low-cycle fatigue life and an acceptable operating range without resonant stress or flutter. The stage was acoustically designed with airfoil counts in the FEGV and core stator to minimize noise. A fan/FEGV tone analysis developed separately under NASA contract was used to determine the optimum airfoil counts. The fan stage was matched to the existing nacelle, designed under the previous P&W low-noise contract, to form a fan/nacelle model for wind tunnel testing. It is an axisymmetric nacelle for convenience in testing and analysis. Previous testing confirmed that the nacelle performed as required at various aircraft operating conditions.

  7. Fuel cell system with combustor-heated reformer

    DOEpatents

    Pettit, William Henry

    2000-01-01

    A fuel cell system including a fuel reformer heated by a catalytic combustor fired by anode effluent and/or fuel from a liquid fuel supply providing fuel for the fuel cell. The combustor includes a vaporizer section heated by the combustor exhaust gases for vaporizing the fuel before feeding it into the combustor. Cathode effluent is used as the principle oxidant for the combustor.

  8. LIGHT SOURCE: Conceptual design of Hefei advanced light source

    NASA Astrophysics Data System (ADS)

    Li, Wei-Min; Wang, Lin; Feng, Guang-Yao; Zhang, Shan-Cai; Wu, Cong-Feng; Xu, Hong-Liang; Liu, Zu-Ping

    2009-06-01

    The conceptual of Hefei Advanced Light Source, which is an advanced VUV and Soft X-ray source, was developed at NSRL of USTC. According to the synchrotron radiation user requirements and the trends of SR source development, some accelerator-based schemes were considered and compared; furthermore storage ring with ultra low emittance was adopted as the baseline scheme of HALS. To achieve ultra low emittance, some focusing structures were studied and optimized in the lattice design. Compromising of emittance, on-momentum and off-momentum dynamic aperture and ring scale, five bend acromat (FBA) was employed. In the preliminary design of HALS, the emittance was reduced to sub nm · rad, thus the radiation up to water window has full lateral coherence. The brilliance of undulator radiation covering several eVs to keVs range is higher than that of HLS by several orders. The HALS should be one of the most advanced synchrotron radiation light sources in the world.

  9. Advanced Gas Turbine (AGT) powertrain system

    NASA Technical Reports Server (NTRS)

    Helms, H. E.; Kaufeld, J.; Kordes, R.

    1981-01-01

    A 74.5 kW(100 hp) advanced automotive gas turbine engine is described. A design iteration to improve the weight and production cost associated with the original concept is discussed. Major rig tests included 15 hours of compressor testing to 80% design speed and the results are presented. Approximately 150 hours of cold flow testing showed duct loss to be less than the design goal. Combustor test results are presented for initial checkout tests. Turbine design and rig fabrication is discussed. From a materials study of six methods to fabricate rotors, two have been selected for further effort. A discussion of all six methods is given.

  10. Adaptive Modeling, Engineering Analysis and Design of Advanced Aerospace Vehicles

    NASA Technical Reports Server (NTRS)

    Mukhopadhyay, Vivek; Hsu, Su-Yuen; Mason, Brian H.; Hicks, Mike D.; Jones, William T.; Sleight, David W.; Chun, Julio; Spangler, Jan L.; Kamhawi, Hilmi; Dahl, Jorgen L.

    2006-01-01

    This paper describes initial progress towards the development and enhancement of a set of software tools for rapid adaptive modeling, and conceptual design of advanced aerospace vehicle concepts. With demanding structural and aerodynamic performance requirements, these high fidelity geometry based modeling tools are essential for rapid and accurate engineering analysis at the early concept development stage. This adaptive modeling tool was used for generating vehicle parametric geometry, outer mold line and detailed internal structural layout of wing, fuselage, skin, spars, ribs, control surfaces, frames, bulkheads, floors, etc., that facilitated rapid finite element analysis, sizing study and weight optimization. The high quality outer mold line enabled rapid aerodynamic analysis in order to provide reliable design data at critical flight conditions. Example application for structural design of a conventional aircraft and a high altitude long endurance vehicle configuration are presented. This work was performed under the Conceptual Design Shop sub-project within the Efficient Aerodynamic Shape and Integration project, under the former Vehicle Systems Program. The project objective was to design and assess unconventional atmospheric vehicle concepts efficiently and confidently. The implementation may also dramatically facilitate physics-based systems analysis for the NASA Fundamental Aeronautics Mission. In addition to providing technology for design and development of unconventional aircraft, the techniques for generation of accurate geometry and internal sub-structure and the automated interface with the high fidelity analysis codes could also be applied towards the design of vehicles for the NASA Exploration and Space Science Mission projects.

  11. Numerical optimization design of advanced transonic wing configurations

    NASA Technical Reports Server (NTRS)

    Cosentino, G. B.; Holst, T. L.

    1985-01-01

    A computationally efficient and versatile technique for use in the design of advanced transonic wing configurations has been developed. A reliable and fast transonic wing flow-field analysis program, TWING, has been coupled with a modified quasi-Newton method, unconstrained optimization algorithm, QNMDIF, to create a new design tool. Fully three-dimensional wing designs utilizing both specified wing pressure disributions and drag-to-lift ratio minimization as design objectives are demonstrated. Because of the high computational efficiency of each of the components of the design code, in particular the vectorization of TWING and the high speed of the Cray X-MP vector computer, the computer time required for a typical wing design is reduced by approximately an order of magnitude over previous methods. In the results presented here, this computed wave drag has been used as the quantity to be optimized (minimized) with great success, yielding wing designs with nearly shock-free (zero wave drag) pressure distributions and very reasonable wing section shapes.

  12. Numerical optimization design of advanced transonic wing configurations

    NASA Technical Reports Server (NTRS)

    Cosentino, G. B.; Holst, T. L.

    1984-01-01

    A computationally efficient and versatile technique for use in the design of advanced transonic wing configurations has been developed. A reliable and fast transonic wing flow-field analysis program, TWING, has been coupled with a modified quasi-Newton method, unconstrained optimization algorithm, QNMDIF, to create a new design tool. Fully three-dimensional wing designs utilizing both specified wing pressure distributions and drag-to-lift ration minimization as design objectives are demonstrated. Because of the high computational efficiency of each of the components of the design code, in particular the vectorization of TWING and the high speed of the Cray X-MP vector computer, the computer time required for a typical wing design is reduced by approximately an order of magnitude over previous methods. In the results presented here, this computed wave drag has been used as the quantity to be optimized (minimized) with great success, yielding wing designs with nearly shock-free (zero wave drag) pressure distributions and very reasonable wing section shapes.

  13. Advanced Antenna Design for NASA's EcoSAR Instrument

    NASA Technical Reports Server (NTRS)

    Du Toit, Cornelis F.; Deshpande, Manohar; Rincon, Rafael F.

    2016-01-01

    Advanced antenna arrays were designed for NASA's EcoSAR airborne radar instrument. EcoSAR is a beamforming synthetic aperture radar instrument designed to make polarimetric and "single pass" interferometric measurements of Earth surface parameters. EcoSAR's operational requirements of a 435MHz center frequency with up to 200MHz bandwidth, dual polarization, high cross-polarization isolation (> 30 dB), +/- 45deg beam scan range and antenna form-factor constraints imposed stringent requirements on the antenna design. The EcoSAR project successfully developed, characterized, and tested two array antennas in an anechoic chamber. EcoSAR's first airborne campaign conducted in the spring of 2014 generated rich data sets of scientific and engineering value, demonstrating the successful operation of the antennas.

  14. Sandia Advanced MEMS Design Tools, Version 2.0

    SciTech Connect

    Allen, Jim; McBrayer, John; Miller, Sam; Rodgers, Steve; montague, Steve; Sniegowski, Jeff; Jakubczak, Jay; Yarberry, Vic; Barnes, Steve; Priddy, Brian; Reyes, David; Westling, Belinda

    2002-06-13

    Sandia Advanced MEMS Design Tools is a 5-level surface micromachine fabrication technology, which customers internal and external to Sandia can access to fabricate prototype MEMS devices. This CD contains an integrated set of electronic files that: a) Describe the SUMMiT V fabrication process b) Provide enabling educational information (including pictures, videos, technical information) c)Facilitate the process of designing MEMS with the SUMMiT process (prototype file, Design Rule Checker, Standard Parts Library) d) Facilitate the process of having MEMS fabricated at SNL e) Facilitate the process of having post-fabrication services performed While there exist some files on the CD that are used in conjunction with the software AutoCAD, these files are not intended for use independent of the CD. NOTE: THE CUSTOMER MUST PURCHASE HIS/HER OWN COPY OF AutoCAD TO USE WITH THESE FILES.

  15. Sandia Advanced MEMS Design Tools v. 3.0

    SciTech Connect

    Yarberry, Victor R.; Allen, James J.; Lantz, Jeffrey W.; Priddy, Brian; Westlin, Belinda; Young, Andrew

    2016-08-25

    This is a major revision to the Sandia Advanced MEMS Design Tools. It replaces all previous versions. New features in this version: Revised to support AutoCAD 2014 and 2015 This CD contains an integrated set of electronic files that: a) Describe the SUMMiT V fabrication process b) Provide enabling educational information (including pictures, videos, technical information) c) Facilitate the process of designing MEMS with the SUMMiT process (prototype file, Design Rule Checker, Standard Parts Library) d) Facilitate the process of having MEMS fabricated at Sandia National Laboratories e) Facilitate the process of having post-fabrication services performed. While there exists some files on the CD that are used in conjunction with software package AutoCAD, these files are not intended for use independent of the CD. Note that the customer must purchase his/her own copy of AutoCAD to use with these files.

  16. Combustor oscillating pressure stabilization and method

    DOEpatents

    Gemmen, Randall S.; Richards, George A.; Yip, Mui-Tong Joseph; Robey, Edward H.; Cully, Scott R.; Addis, Richard E.

    1998-01-01

    High dynamic pressure oscillations in hydrocarbon-fueled combustors typically occur when the transport time of the fuel to the flame front is at some fraction of the acoustic period. These oscillations are reduced to acceptably lower levels by restructuring or repositioning the flame front in the combustor to increase the transport time. A pilot flame front located upstream of the oscillating flame and pulsed at a selected frequency and duration effectively restructures and repositions the oscillating flame in the combustor to alter the oscillation-causing transport time.

  17. Combustor oscillating pressure stabilization and method

    DOEpatents

    Gemmen, R.S.; Richards, G.A.; Yip, M.T.J.; Robey, E.H.; Cully, S.R.; Addis, R.E.

    1998-08-11

    High dynamic pressure oscillations in hydrocarbon-fueled combustors typically occur when the transport time of the fuel to the flame front is at some fraction of the acoustic period. These oscillations are reduced to acceptably lower levels by restructuring or repositioning the flame front in the combustor to increase the transport time. A pilot flame front located upstream of the oscillating flame and pulsed at a selected frequency and duration effectively restructures and repositions the oscillating flame in the combustor to alter the oscillation-causing transport time. 7 figs.

  18. Chaos in an imperfectly premixed model combustor

    SciTech Connect

    Kabiraj, Lipika Saurabh, Aditya; Paschereit, Christian O.; Karimi, Nader; Sailor, Anna; Mastorakos, Epaminondas; Dowling, Ann P.

    2015-02-15

    This article reports nonlinear bifurcations observed in a laboratory scale, turbulent combustor operating under imperfectly premixed mode with global equivalence ratio as the control parameter. The results indicate that the dynamics of thermoacoustic instability correspond to quasi-periodic bifurcation to low-dimensional, deterministic chaos, a route that is common to a variety of dissipative nonlinear systems. The results support the recent identification of bifurcation scenarios in a laminar premixed flame combustor (Kabiraj et al., Chaos: Interdiscip. J. Nonlinear Sci. 22, 023129 (2012)) and extend the observation to a practically relevant combustor configuration.

  19. Advanced Wet Tantalum Capacitors: Design, Specifications and Performance

    NASA Technical Reports Server (NTRS)

    Teverovsky, Alexander

    2017-01-01

    Insertion of new types of commercial, high volumetric efficiency wet tantalum capacitors in space systems requires reassessment of the existing quality assurance approaches that have been developed for capacitors manufactured to MIL-PRF-39006 requirements. The specifics of wet electrolytic capacitors is that leakage currents flowing through electrolyte can cause gas generation resulting in building up of internal gas pressure and rupture of the case. The risk associated with excessive leakage currents and increased pressure is greater for high value advanced wet tantalum capacitors, but it has not been properly evaluated yet. This presentation gives a review of specifics of the design, performance, and potential reliability risks associated with advanced wet tantalum capacitors. Problems related to setting adequate requirements for DPA, leakage currents, hermeticity, stability at low and high temperatures, ripple currents for parts operating in vacuum, and random vibration testing are discussed. Recommendations for screening and qualification to reduce risks of failures have been suggested.

  20. Advanced Wet Tantalum Capacitors: Design, Specifications and Performance

    NASA Technical Reports Server (NTRS)

    Teverovsky, Alexander

    2016-01-01

    Insertion of new types of commercial, high volumetric efficiency wet tantalum capacitors in space systems requires reassessment of the existing quality assurance approaches that have been developed for capacitors manufactured to MIL-PRF-39006 requirements. The specifics of wet electrolytic capacitors is that leakage currents flowing through electrolyte can cause gas generation resulting in building up of internal gas pressure and rupture of the case. The risk associated with excessive leakage currents and increased pressure is greater for high value advanced wet tantalum capacitors, but it has not been properly evaluated yet. This presentation gives a review of specifics of the design, performance, and potential reliability risks associated with advanced wet tantalum capacitors. Problems related to setting adequate requirements for DPA, leakage currents, hermeticity, stability at low and high temperatures, ripple currents for parts operating in vacuum, and random vibration testing are discussed. Recommendations for screening and qualification to reduce risks of failures have been suggested.

  1. Advanced Space Suit Portable Life Support Subsystem Packaging Design

    NASA Technical Reports Server (NTRS)

    Howe, Robert; Diep, Chuong; Barnett, Bob; Thomas, Gretchen; Rouen, Michael; Kobus, Jack

    2006-01-01

    This paper discusses the Portable Life Support Subsystem (PLSS) packaging design work done by the NASA and Hamilton Sundstrand in support of the 3 future space missions; Lunar, Mars and zero-g. The goal is to seek ways to reduce the weight of PLSS packaging, and at the same time, develop a packaging scheme that would make PLSS technology changes less costly than the current packaging methods. This study builds on the results of NASA s in-house 1998 study, which resulted in the "Flex PLSS" concept. For this study the present EMU schematic (low earth orbit) was used so that the work team could concentrate on the packaging. The Flex PLSS packaging is required to: protect, connect, and hold the PLSS and its components together internally and externally while providing access to PLSS components internally for maintenance and for technology change without extensive redesign impact. The goal of this study was two fold: 1. Bring the advanced space suit integrated Flex PLSS concept from its current state of development to a preliminary design level and build a proof of concept mockup of the proposed design, and; 2. "Design" a Design Process, which accommodates both the initial Flex PLSS design and the package modifications, required to accommodate new technology.

  2. Numerical Design of Drawbeads for Advanced High Strength Steel Sheets

    NASA Astrophysics Data System (ADS)

    Keum, Y. T.; Kim, D. J.; Kim, G. S.

    2010-06-01

    The map for designing the drawbeads used in the stamping dies for advanced high strength steel (AHSS) sheets is numerically investigated and its application is introduced. The bending limit of AHSS sheet is determined from the extreme R/t's obtained simulating numerically the plane-strain process formed by the cylindrical punches and dies with various radii. In addition, the forming allowance defined by the difference between FLC0 and the strain after passing the drawbead, which is observed by the numerical simulation of drawbead pulling test, is computed. Based on the bending limit and forming allowance, the design map for determining the height, width, and shoulder radius of the drawbead which are key parameters in the drawbead design and depend on the restraining force is constructed by aid of the equivalent drawbead model. A drawbead of the stamping die for forming a channel-typed panel is designed by using the design map, and the formability and springback of the panel to be formed are numerically evaluated, from which the availability of the design map is demonstrated.

  3. Characterization and Simulation of Thermoacoustic Instability in a Low Emissions Combustor Prototype

    NASA Technical Reports Server (NTRS)

    DeLaat, John C.; Paxson, Daniel E.

    2008-01-01

    Extensive research is being done toward the development of ultra-low-emissions combustors for aircraft gas turbine engines. However, these combustors have an increased susceptibility to thermoacoustic instabilities. This type of instability was recently observed in an advanced, low emissions combustor prototype installed in a NASA Glenn Research Center test stand. The instability produces pressure oscillations that grow with increasing fuel/air ratio, preventing full power operation. The instability behavior makes the combustor a potentially useful test bed for research into active control methods for combustion instability suppression. The instability behavior was characterized by operating the combustor at various pressures, temperatures, and fuel and air flows representative of operation within an aircraft gas turbine engine. Trends in instability behavior vs. operating condition have been identified and documented. A simulation developed at NASA Glenn captures the observed instability behavior. The physics-based simulation includes the relevant physical features of the combustor and test rig, employs a Sectored 1-D approach, includes simplified reaction equations, and provides time-accurate results. A computationally efficient method is used for area transitions, which decreases run times and allows the simulation to be used for parametric studies, including control method investigations. Simulation results show that the simulation exhibits a self-starting, self-sustained combustion instability and also replicates the experimentally observed instability trends vs. operating condition. Future plans are to use the simulation to investigate active control strategies to suppress combustion instabilities and then to experimentally demonstrate active instability suppression with the low emissions combustor prototype, enabling full power, stable operation.

  4. Advances in designs for Alzheimer's disease clinical trials.

    PubMed

    Cummings, Jeffrey; Gould, Heath; Zhong, Kate

    2012-01-01

    There is an urgent need to identify new treatments for the rapidly growing population of people with Alzheimer's disease (AD). Innovations in clinical trial designs many help to reduce development time, provide more definitive answers regarding drug efficacy, and facilitate prioritizing compounds to be advanced to Phase III clinical trials. Standard designs compare drug and placebo changes from baseline on a rating scale. Baysian adaptive clinical trials allow the use of data collected in the trial to modify doses, sample size, trial duration, and entry criteria in an ongoing way as the data are collected. Disease-modification is supported by findings on staggered start and delayed withdrawal designs. Futility designs can use historical controls and may shorten trial duration. Combination therapy designs may allow investigation of additive or synergistic treatment effects. Novel trial selection criteria allow investigation of treatment effects in asymptomatic or minimally symptomatic, prodromal AD populations. The Clinical Dementia Rating-Sum of Boxes (CDR-SOB) can be considered as a single trial outcome in early disease populations. Alternate forms of the Alzheimer's Disease Assessment Scale-Cognitive Portion (ADAS-cog), computerized measures, and pharmacoeconomic scales provide new and relevant information on drug effects. Comparative dose strategies are used in trials of symptomatic agents, and novel methods including withdrawal designs, symptom emergence analyses, and sequential designs are being utilized to assess the efficacy of putative psychotropic agents. The choice of trial design is driven by the question to be answered by the clinical trial; an increasing number of design approaches are available and may be useful in accelerating and refining AD drug development.

  5. Advances in designs for Alzheimer’s disease clinical trials

    PubMed Central

    Cummings, Jeffrey; Gould, Heath; Zhong, Kate

    2012-01-01

    There is an urgent need to identify new treatments for the rapidly growing population of people with Alzheimer’s disease (AD). Innovations in clinical trial designs many help to reduce development time, provide more definitive answers regarding drug efficacy, and facilitate prioritizing compounds to be advanced to Phase III clinical trials. Standard designs compare drug and placebo changes from baseline on a rating scale. Baysian adaptive clinical trials allow the use of data collected in the trial to modify doses, sample size, trial duration, and entry criteria in an ongoing way as the data are collected. Disease-modification is supported by findings on staggered start and delayed withdrawal designs. Futility designs can use historical controls and may shorten trial duration. Combination therapy designs may allow investigation of additive or synergistic treatment effects. Novel trial selection criteria allow investigation of treatment effects in asymptomatic or minimally symptomatic, prodromal AD populations. The Clinical Dementia Rating-Sum of Boxes (CDR-SOB) can be considered as a single trial outcome in early disease populations. Alternate forms of the Alzheimer’s Disease Assessment Scale-Cognitive Portion (ADAS-cog), computerized measures, and pharmacoeconomic scales provide new and relevant information on drug effects. Comparative dose strategies are used in trials of symptomatic agents, and novel methods including withdrawal designs, symptom emergence analyses, and sequential designs are being utilized to assess the efficacy of putative psychotropic agents. The choice of trial design is driven by the question to be answered by the clinical trial; an increasing number of design approaches are available and may be useful in accelerating and refining AD drug development. PMID:23383393

  6. Thermally-Choked Combustor Technology

    NASA Technical Reports Server (NTRS)

    Knuth, William H.; Gloyer, P.; Goodman, J.; Litchford, R. J.

    1993-01-01

    A program is underway to demonstrate the practical feasibility of thermally-choked combustor technology with particular emphasis on rocket propulsion applications. Rather than induce subsonic to supersonic flow transition in a geometric throat, the goal is to create a thermal throat by adding combustion heat in a diverging nozzle. Such a device would have certain advantages over conventional flow accelerators assuming that the pressure loss due to heat addition does not severely curtail propulsive efficiency. As an aid to evaluation, a generalized one-dimensional compressible flow analysis tool was constructed. Simplified calculations indicate that the process is fluid dynamically and thermodynamically feasible. Experimental work is also being carried out in an attempt to develop, assuming an array of practical issues are surmountable, a practical bench-scale demonstrator using high flame speed H2/O2 combustibles.

  7. Design and Numerical Simulation of Two Dimensional Ultra Compact Combustor Model Sections for Experimental Observation of Cavity-Vane Flow Interactions

    DTIC Science & Technology

    2005-09-01

    Solidworks 3.04 used to build the test rig structure database, Gridgen v15 used to construct an unstructured grid within the configuration database, and...to the interior of the area or volume being built by the grid solver. In Gridgen , a boundary decay of ‘0’ indicates no correlation between...baseline models were designed as shown in Figure 7, with the experimental model Gridgen basic structure database from Anisko used, and the 1.5-in cavity

  8. Advances in aircraft design: Multiobjective optimization and a markup language

    NASA Astrophysics Data System (ADS)

    Deshpande, Shubhangi

    Today's modern aerospace systems exhibit strong interdisciplinary coupling and require a multidisciplinary, collaborative approach. Analysis methods that were once considered feasible only for advanced and detailed design are now available and even practical at the conceptual design stage. This changing philosophy for conducting conceptual design poses additional challenges beyond those encountered in a low fidelity design of aircraft. This thesis takes some steps towards bridging the gaps in existing technologies and advancing the state-of-the-art in aircraft design. The first part of the thesis proposes a new Pareto front approximation method for multiobjective optimization problems. The method employs a hybrid optimization approach using two derivative free direct search techniques, and is intended for solving blackbox simulation based multiobjective optimization problems with possibly nonsmooth functions where the analytical formof the objectives is not known and/or the evaluation of the objective function(s) is very expensive (very common in multidisciplinary design optimization). A new adaptive weighting scheme is proposed to convert a multiobjective optimization problem to a single objective optimization problem. Results show that the method achieves an arbitrarily close approximation to the Pareto front with a good collection of well-distributed nondominated points. The second part deals with the interdisciplinary data communication issues involved in a collaborative mutidisciplinary aircraft design environment. Efficient transfer, sharing, and manipulation of design and analysis data in a collaborative environment demands a formal structured representation of data. XML, a W3C recommendation, is one such standard concomitant with a number of powerful capabilities that alleviate interoperability issues. A compact, generic, and comprehensive XML schema for an aircraft design markup language (ADML) is proposed here to provide a common language for data

  9. Design calculations for the ANS (Advanced Neutron Source) cold source

    SciTech Connect

    Lillie, R.A.; Alsmiller, R.G. Jr.

    1988-01-01

    The calculation procedure, based on discrete ordinates transport methods, that is being used to carry out design calculations for the Advanced Neutron Source cold source is described. Calculated results on the gain in cold neutron flux produced by a liquid deuterium cold source are compared with experimental data and with calculated data previously obtained by P. Ageron et al., at the Institute Max von Laue-Paul Langevin in Grenoble, France. Calculated results are also presented that indicated how the flux of cold neutrons vary with cold source parameters. 23 refs., 5 figs., 3 tabs.

  10. Advanced Crew Interface Designs for Safer Air Travel

    NASA Technical Reports Server (NTRS)

    1998-01-01

    NASA is developing advanced crew interface designs to improve performance for safe air travel. NASA's goal is to provide enabling technologies that will increase aviation safety by a factor of five within 10 years, and by a factor of ten within 25 years. This research is part of NASA's Aeronautics and Space Transportation Technology (ASTT) Enterprise's strategy to sustain U.S. leadership in aeronautics and space. The Enterprise has set bold goals that are grouped into Three Pillars: Global Civil Aviation, Revolutionary Technology Leaps and Access to Space.

  11. Advanced Cryo-Tanks Structural Design Investigated in CHATT

    NASA Astrophysics Data System (ADS)

    Sippel, Martin; Kopp, Alexander; Mattsson, David; Koussios, Sotiris

    2014-06-01

    An EU-funded study called CHATT (Cryogenic Hypersonic Advanced Tank Technologies) has been initiated early 2012 and recently passed its mid-term milestone. The project CHATT is part of the European Commission's Seventh Framework Programme and run on behalf of the Commission by DLR-SART in a multinational collaboration. One of the core objectives is to investigate Carbon Fiber Reinforced Plastic (CFRP) cryogenic pressure tanks. Four different subscale CFRP-tanks are planned to be designed, manufactured, and tested.The paper outlines the study logic of CHATT, gives a presentation of the technology development tasks, and summarizes available research results on the liner testing and CFRP-tank manufacturing.

  12. Optical measurement and visualization in high-pressure high-temperature aviation gas turbine combustors

    NASA Astrophysics Data System (ADS)

    Hicks, Yolanda R.; Locke, Randy J.; Anderson, Robert C.

    2000-08-01

    Planar laser-induced fluorescence (PLIF), planar Mie scattering (Pmie), and linear)1-D) spontaneous Raman scattering are applied to flame tube and sector combustors that burn Jet-A fuel at a range of inlet temperatures and pressures that simulate conditions expected in future high-performance civilian gas turbine engines. Chemiluminescence arising from C2 in the flame was also imaged. Flame spectral emissions measurements were obtained using a scanning spectrometer. Several different advanced concept fuel injectors were examined. First-ever PLIF and chemiluminescence data are presented from the 60-atm gas turbine combustor facility.

  13. Optical Measurement and Visualization in High-Pressure, High-Temperature, Aviation Gas Turbine Combustors

    NASA Technical Reports Server (NTRS)

    Hicks, Yolanda R.; Anderson, Robert C.; Locke, Randy J.

    2000-01-01

    Planar laser-induced fluorescence (PLIF), planar Mie scattering (PMie), and linear (1-D) spontaneous Raman scattering are applied to flame tube and sector combustors that burn Jet-A fuel at a range of inlet temperatures and pressures that simulate conditions expected in future high-performance civilian gas turbine engines. Chemiluminescence arising from C2 in the flame was also imaged. Flame spectral emissions measurements were obtained using a scanning spectrometer. Several different advanced concept fuel injectors were examined. First-ever PLIF and chemiluminescence data are presented from the 60-atm Gas turbine combustor facility.

  14. A methanol/oxygen burning combustor for an aircraft auxiliary emergency power unit

    SciTech Connect

    Carr, E.; Todd, H. , Burnley, Lancashire )

    1989-01-01

    The development of advanced single-engine aircraft with reduced stability and Fly-by-Wire control systems requires the provision of emergency hydraulic and electrical power from a stored energy system. The desire to achieve this objective using readily available fluids of low toxicity has led to the development of a methanol/oxygen burning combustor to provide a hot gas stream to drive a small turbine. The paper describes the performance of a 300 kW output combustor, which is cooled by the methanol consumed.

  15. Low NOx heavy fuel combustor concept program, phase 1

    NASA Technical Reports Server (NTRS)

    Cutrone, M. B.

    1981-01-01

    Combustion tests were completed with seven concepts, including three rich/lean concepts, three lean/lean concepts, and one catalytic combustor concept. Testing was conducted with ERBS petroleum distillate, petroleum residual, and SRC-II coal-derived liquid fuels over a range of operating conditions for the 12:1 pressure ratio General Electric MS7001E heavy-duty turbine. Blends of ERBS and SRC-II fuels were used to vary fuel properties over a wide range. In addition, pyridine was added to the ERBS and residual fuels to vary nitrogen level while holding other fuel properties constant. Test results indicate that low levels of NOx and fuel-bound nitrogen conversion can be achieved with the rich/lean combustor concepts for fuels with nitrogen contents up to 1.0% by weight. Multinozzle rich/lean Concept 2 demonstrated dry low Nox emissions within 10-15% of the EPA New Source Performance Standards goals for SRC-II fuel, with yields of approximately 15%, while meeting program goals for combustion efficiency, pressure drop, and exhaust gas temperature profile. Similar, if not superior, potential was demonstrated by Concept 3, which is a promising rich/lean combustor design.

  16. Combustor assembly in a gas turbine engine

    DOEpatents

    Wiebe, David J; Fox, Timothy A

    2013-02-19

    A combustor assembly in a gas turbine engine. The combustor assembly includes a combustor device coupled to a main engine casing, a first fuel injection system, a transition duct, and an intermediate duct. The combustor device includes a flow sleeve for receiving pressurized air and a liner disposed radially inwardly from the flow sleeve. The first fuel injection system provides fuel that is ignited with the pressurized air creating first working gases. The intermediate duct is disposed between the liner and the transition duct and defines a path for the first working gases to flow from the liner to the transition duct. An intermediate duct inlet portion is associated with a liner outlet and allows movement between the intermediate duct and the liner. An intermediate duct outlet portion is associated with a transition duct inlet section and allows movement between the intermediate duct and the transition duct.

  17. Experimental clean combustor program, phase 2

    NASA Technical Reports Server (NTRS)

    Roberts, R.; Peduzzi, A.; Vitti, G. E.

    1976-01-01

    The alternate fuels investigation objective was to experimentally determine the impacts, if any, on exhaust emissions, performance, and durability characteristics of the hybrid and vorbix low pollution combustor concepts when operated on test fuels which simulate composition and property changes which might result from future broadened aviation turbine fuel specifications or use of synthetically derived crude feedstocks. Results of the program indicate a significant increase in CO and small NOX increase in emissions at idle for both combustor concepts, and an increase in THC for the vorbix concept. Minimal impact was observed on gaseous emissions at high power. The vorbix concept exhibited significant increase in exhaust smoke with increasing fuel aromatic content. Altitude stability was not affected for the vorbix combustor, but was substantially reduced for the hybrid concept. Severe carbon deposition was observed in both combustors following limited endurance testing with No. 2 home heat fuel. Liner temperature levels were insensitive to variations in aromatic content over the range of conditions investigated.

  18. Planar measurement of flow field parameters in a nonreacting supersonic combustor using laser-induced iodine fluorescence

    NASA Technical Reports Server (NTRS)

    Hartfield, Roy J., Jr.; Hollo, Steven D.; Mcdaniel, James C.

    1990-01-01

    A nonintrusive optical technique, laser-induced iodine fluorescence, has been used to obtain planar measurements of flow field parameters in the supersonic mixing flow field of a nonreacting supersonic combustor. The combustor design used in this work was configured with staged transverse sonic injection behind a rearward-facing step into a Mach 2.07 free stream. A set of spatially resolved measurements of temperature and injectant mole fraction has been generated. These measurements provide an extensive and accurate experimental data set required for the validation of computational fluid dynamic codes developed for the calculation of highly three-dimensional combustor flow fields.

  19. Pollution emissions from single swirl-can combustor modules at parametric test conditions

    NASA Technical Reports Server (NTRS)

    Mularz, E. J.; Wear, J. D.; Verbulecz, P. W.

    1975-01-01

    Exhaust pollutant emissions were measured from single swirl-can combustor modules operating over a pressure range of 69 to 276 N/sq cm (100 to 400 psia), over a fuel-air ratio range of 0.01 to 0.04, at an inlet air temperature of 733 K (860 F), and at a constant reference velocity of 23.2 m/sec). Many swirl-can module designs were evaluated; the 11 most promising designs exhibited oxides of nitrogen emission levels lower than that from conventional gas-turbine combustors. Although these single module test results are not necessarily indicative of the performance characteristics of a large array of modules, the results are very promixing and offer a number of module designs that should be tested in a full combustor.

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

    SciTech Connect

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

    2007-10-01

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

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

    NASA Technical Reports Server (NTRS)

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

    1984-01-01

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

  2. Design of vibration compensation interferometer for Experimental Advanced Superconducting Tokamak

    NASA Astrophysics Data System (ADS)

    Yang, Y.; Li, G. S.; Liu, H. Q.; Jie, Y. X.; Ding, W. X.; Brower, D. L.; Zhu, X.; Wang, Z. X.; Zeng, L.; Zou, Z. Y.; Wei, X. C.; Lan, T.

    2014-11-01

    A vibration compensation interferometer (wavelength at 0.532 μm) has been designed and tested for Experimental Advanced Superconducting Tokamak (EAST). It is designed as a sub-system for EAST far-infrared (wavelength at 432.5 μm) poloarimeter/interferometer system. Two Acoustic Optical Modulators have been applied to produce the 1 MHz intermediate frequency. The path length drift of the system is lower than 2 wavelengths within 10 min test, showing the system stability. The system sensitivity has been tested by applying a periodic vibration source on one mirror in the system. The vibration is measured and the result matches the source period. The system is expected to be installed on EAST by the end of 2014.

  3. Optimal design application on the advanced aeroelastic rotor blade

    NASA Technical Reports Server (NTRS)

    Wei, F. S.; Jones, R.

    1985-01-01

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

  4. Conceptual design of the advanced marine reactor MRX

    NASA Astrophysics Data System (ADS)

    1991-02-01

    Design studies on the advanced marine reactors have been done continuously since 1983 at the Japan Atomic Energy Research Institute (JAERI) in order to develop attractive marine reactors for the next generation. At present, two marine reactor concepts are being formulated. One is 100 MWt MRX (Marine Reactor X) for an icebreaker and the other is 300 kWe DRX (Deep-sea Reactor X) for a deep-sea research vessel. They are characterized by an integral type pressurized water reactor (PWR) built-in type control rod drive mechanisms, a water-filled container and a passive decay heat removal system, which realize highly passive safe and compact reactors. This paper is a detailed report including all major results of the MRX design study.

  5. Operational Characteristics of an Ultra Compact Combustor

    DTIC Science & Technology

    2014-03-27

    recirculation conditions. If fuel is mixed into core flows too quickly or escapes into cold spots of a combustor liner , then it will remain...of fuel like a cylinder in a cross flow as it circulates about the cavity. The impact of the flow upon these cylindrical plumes creates a stagnation...combustor liner or the entrainment of cavity flow into core flow within a UCC. Therefore, the test matrix in Table 3.5 was built to highlight changes to

  6. Multiducted Inlet Combustor Research and Development.

    DTIC Science & Technology

    1982-10-01

    qualitative data from the multi-ducted inlet combustor configuration for flow analysis and matematical modeling purposes. The major portion of the support...data on multi-ducted inlet combustor configurations. These efforts will provide the information necessary to perform flow field analysis and aid in the...instrumentation, test program, data reduction, data presentation, flow field analysis and math modelling efforts, and conclusions and recommendations. SECTION 2

  7. Effect of broad properties fuel on injector performance in a reverse flow combustor

    NASA Technical Reports Server (NTRS)

    Raddlebaugh, S. M.; Norgren, C. T.

    1983-01-01

    The effect of fuel type on the performance of various fuel injectors was investigated in a reverse flow combustor. Combustor performance and emissions are documented for simplex pressure atomizing, spill flow, and airblast fuel injectors using a broad properties fuel and compared with performance using Jet A fuel. Test conditions simulated a range of flight conditions including sea level take off, low and high altitude cruise, as well as a parametric evaluation of the effect of increased combustor loading. The baseline simplex injector produced higher emission levels with corresponding lower combustion efficiency with the broad properties fuel. There was little or not loss in performance by the two advanced concept injectors with the broad properties fuel. The airblast injector proved to be especially insensitive to fuel type.

  8. Aerodynamic optimization by simultaneously updating flow variables and design parameters with application to advanced propeller designs

    NASA Technical Reports Server (NTRS)

    Rizk, Magdi H.

    1988-01-01

    A scheme is developed for solving constrained optimization problems in which the objective function and the constraint function are dependent on the solution of the nonlinear flow equations. The scheme updates the design parameter iterative solutions and the flow variable iterative solutions simultaneously. It is applied to an advanced propeller design problem with the Euler equations used as the flow governing equations. The scheme's accuracy, efficiency and sensitivity to the computational parameters are tested.

  9. Techniques for enhancing durability and equivalence ratio control in a rich-lean, three-stage ground power gas turbine combustor

    NASA Technical Reports Server (NTRS)

    Schultz, D. F.

    1982-01-01

    Rig tests of a can-type combustor were performed to demonstrate two advanced ground power engine combustor concepts: steam cooled rich-burn combustor primary zones for enhanced durability; and variable combustor geometry for three stage combustion equivalence ratio control. Both concepts proved to be highly successful in achieving their desired objectives. The steam cooling reduced peak liner temperatures to less than 800 K. This offers the potential of both long life and reduced use of strategic materials for liner fabrication. Three degrees of variable geometry were successfully implemented to control airflow distribution within the combustor. One was a variable blade angle axial flow air swirler to control primary airflow while the other two consisted of rotating bands to control secondary and tertiary or dilution air flow.

  10. Advances in molecular design and synthesis of regioregular polythiophenes.

    PubMed

    Osaka, Itaru; McCullough, Richard D

    2008-09-01

    Regioregular poly(3-alkylthiophene)s (rrP3ATs) are an important class of pi-conjugated polymers that can be used in plastic electronic devices such as solar cells and field-effect transistors. rrP3ATs can be ordered in three dimensions: conformational ordering along the backbone, pi-stacking of flat polymer chains, and lamellar stacking between chains. All of these features lead to the excellent electrical properties of these materials. Creative molecular design and advanced synthesis are critical in controlling the properties of the materials as well as their device performance. This Account reports the advances in molecular design of new functional polythiophenes as well as the associated polymerization methods. Many functionalized regioregular polythiophenes have been designed and synthesized and show fascinating properties such as high conductivity, mobility, chemosensitivity, liquid crystallinity, or chirality. The methods for the synthesis of rrP3ATs are also applicable to other functional side chains. Di- and triblock copolymers consisting of rrP3AT and polyacrylate or polystyrene have also been successfully synthesized, which can facilitate the assembly of the polythiophene segments. The synthesis of rrP3ATs has evolved into a simple and economical system in which the synthesis can be carried out quickly at room temperature and is thus suitable for large-scale manufacturing. Intensive study has revealed that the regioregular polymerization of 3-alkylthiophenes proceeds by a chain-growth mechanism and can be made into a living system. This feature enables precise control of the molecular weight and facile end-group functionalization of the polymer chains, leading to tailor-made regioregular polythiophenes for specific applications. In addition, researchers have recently designed and synthesized regiosymmetric polythiophenesthese are regioregular but not coupled in a head-to-tail fashionby various methods. These reports indicate that these regiosymmetric

  11. Design of Test Support Hardware for Advanced Space Suits

    NASA Technical Reports Server (NTRS)

    Watters, Jeffrey A.; Rhodes, Richard

    2013-01-01

    As a member of the Space Suit Assembly Development Engineering Team, I designed and built test equipment systems to support the development of the next generation of advanced space suits. During space suit testing it is critical to supply the subject with two functions: (1) cooling to remove metabolic heat, and (2) breathing air to pressurize the space suit. The objective of my first project was to design, build, and certify an improved Space Suit Cooling System for manned testing in a 1-G environment. This design had to be portable and supply a minimum cooling rate of 2500 BTU/hr. The Space Suit Cooling System is a robust, portable system that supports very high metabolic rates. It has a highly adjustable cool rate and is equipped with digital instrumentation to monitor the flowrate and critical temperatures. It can supply a variable water temperature down to 34 deg., and it can generate a maximum water flowrate of 2.5 LPM. My next project was to design and build a Breathing Air System that was capable of supply facility air to subjects wearing the Z-2 space suit. The system intakes 150 PSIG breathing air and regulates it to two operating pressures: 4.3 and 8.3 PSIG. It can also provide structural capabilities at 1.5x operating pressure: 6.6 and 13.2 PSIG, respectively. It has instrumentation to monitor flowrate, as well as inlet and outlet pressures. The system has a series of relief valves to fully protect itself in case of regulator failure. Both projects followed a similar design methodology. The first task was to perform research on existing concepts to develop a sufficient background knowledge. Then mathematical models were developed to size components and simulate system performance. Next, mechanical and electrical schematics were generated and presented at Design Reviews. After the systems were approved by the suit team, all the hardware components were specified and procured. The systems were then packaged, fabricated, and thoroughly tested. The next step

  12. Rolling contact mounting arrangement for a ceramic combustor

    DOEpatents

    Boyd, Gary L.; Shaffer, James E.

    1995-01-01

    A combustor assembly having a preestablished rate of thermal expansion is mounted within a gas turbine engine housing having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the combustor assembly. The combustor assembly is constructed of a inlet end portion, a outlet end portion and a plurality of combustor ring segments positioned between the end portions. A mounting assembly is positioned between the combustor assembly and the gas turbine engine housing to allow for the difference in the rate of thermal expansion while maintaining axially compressive force on the combustor assembly to maintain contact between the separate components.

  13. Rolling contact mounting arrangement for a ceramic combustor

    DOEpatents

    Boyd, G.L.; Shaffer, J.E.

    1995-10-17

    A combustor assembly having a preestablished rate of thermal expansion is mounted within a gas turbine engine housing having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the combustor assembly. The combustor assembly is constructed of a inlet end portion, a outlet end portion and a plurality of combustor ring segments positioned between the end portions. A mounting assembly is positioned between the combustor assembly and the gas turbine engine housing to allow for the difference in the rate of thermal expansion while maintaining axially compressive force on the combustor assembly to maintain contact between the separate components. 3 figs.

  14. NOx Emissions Characteristics and Correlation Equations of Two P and W's Axially Staged Sector Combustors Developed Under NASA Environmentally Responsible Aviation (ERA) Project

    NASA Technical Reports Server (NTRS)

    He, Zhuohui J.

    2017-01-01

    Two P&W (Pratt & Whitney)'s axially staged sector combustors have been developed under NASA's Environmentally Responsible Aviation (ERA) project. One combustor was developed under ERA Phase I, and the other was developed under ERA Phase II. Nitrogen oxides (NOx) emissions characteristics and correlation equations for these two sector combustors are reported in this article. The Phase I design was to optimize the NOx emissions reduction potential, while the Phase II design was more practical and robust. Multiple injection points and fuel staging strategies are used in the combustor design. Pilot-stage injectors are located on the front dome plate of the combustor, and main-stage injectors are positioned on the top and bottom (Phase I) or on the top only (Phase II) of the combustor liners downstream. Low power configuration uses only pilot-stage injectors. Main-stage injectors are added to high power configuration to help distribute fuel more evenly and achieve lean burn throughout the combustor yielding very low NOx emissions. The ICAO (International Civil Aviation Organization) landing-takeoff NOx emissions are verified to be 88 percent (Phase I) and 76 percent (Phase II) under the ICAO CAEP/6 (Committee on Aviation Environmental Protection 6th Meeting) standard, exceeding the ERA project goal of 75 percent reduction, and the combustors proved to have stable combustion with room to maneuver on fuel flow splits for operability.

  15. Swirl-can combustor performance to near-stoichiometric fuel-air ratio

    NASA Technical Reports Server (NTRS)

    Diehl, L. A.; Biaglow, J. A.

    1976-01-01

    Emissions and performance characteristics were determined for full-annulus swirl-can modular combustors operated to near stoichiometric fuel air ratios. The purposes of the tests were to obtain stoichiometric data at inlet air temperatures up to 894 K and to determine the effect of module number by investigating 120 and 72 module swirl-can combustors. The maximum average exit temperature obtained with the 120-module swirl-can combustor was 2465 K with a combustion efficiency of 95 percent at an inlet-air temperature of 894 K. The 72-module swirl-can combustor reached a maximum average exit temperature of 2306 K with a combustion efficiency of 92 percent at an inlet air temperature of 894 K. At a constant inlet air temperature, maximum oxides of nitrogen emission index values occurred at a fuel-air ratio of 0.037 for the 72-module design and 0.044 for the 120-module design. The combustor average exit temperature and combustion efficiency were calculated from emissions measurements. The measured emissions included carbon monoxide, unburned hydrocarbons, oxides of nitrogen, and smoke.

  16. Factors that limit control effectiveness in self-excited noise driven combustors

    NASA Astrophysics Data System (ADS)

    Crawford, Jackie H., III

    This thesis considers what limits control effectiveness in self-excited, noise driven, combustors using a full Strouhal number thermo-acoustic model with the ultimate aim of learning how to design combustors to be responsive to feedback control of combustion instabilities. The inclusion of time delays in the volumetric heat release perturbation models create unique behavioral characteristics which are not properly reproduced within current low Strouhal number thermo-acoustic models used for feedback control. New analysis tools using probability density functions are introduced in this thesis which enable exact expressions for the statistics of a time delayed system. Additionally, preexisting tools from applied mathematics and control theory for spectral analysis of time delay systems are introduced to the combustion community. These new analysis tools can be used to extend sensitivity function analysis used in control theory to explain limits to control effectiveness in self-excited combustors. The control effectiveness of self-excited combustors with actuator constraints are found to be most sensitive to the location of non-minimum phase zeros. Modeling the non-minimum phase zeros correctly require accurate volumetric heat release perturbation models. Designs that removes non-minimum phase zeros are more likely to have poles in the right hand complex plane. As a result, unstable combustors are inherently more responsive to feedback control.

  17. Suppression of Combustor-Inlet Interaction in a Scramjet Engine under Mach 4 Flight Conditions

    NASA Astrophysics Data System (ADS)

    Kobayashi, Kan; Kanda, Takeshi; Tomioka, Sadatake; Tani, Kouichiro; Sakuranaka, Noboru; Mitani, Tohru

    A sidewall-compression-type scramjet engine was tested under Mach 4 flight conditions. The tested engine had an inlet, a constant cross-sectional area isolator, a constant cross-sectional area combustor, a diverging combustor, and an internal nozzle. In a previous study under the same flight conditions, the maximum thrust increment using fuel injection within the constant-area combustor was 1,380 N at an equivalence ratio of 0.31, and further fuel injection resulted in combustor-inlet interaction (designated as CII). To suppress the CII in the present study, we attempted (1) two-stage fuel injection within the constant-area combustor and the diverging combustor and (2) a boundary layer bleed on the top wall. The former was to suppress heat release around the first-stage fuel injectors in the constant-area combustor, and the latter was to decrease interaction length by decreasing the boundary layer thickness on the top wall. In the case of two-stage fuel injection, the maximum thrust increment was 2,230 N at an equivalence ratio of 0.63. In the case of the boundary layer bleed, on the other hand, the maximum thrust increment was 2,300 N at an equivalence ratio of 0.66. Thus, two-stage fuel injection and boundary layer bleed led to 62% and 67% higher maximum thrust increments than that obtained in the previous study, respectively. Finally, both the two-stage fuel injection and boundary layer bleed were applied simultaneously to obtain the best thrust performance, and the maximum thrust increment was 2,560 N at an equivalence ratio of 0.95. As a result, we obtained an 86% higher maximum thrust increment than that in the previous study. The thrust achievement factor, which was defined as the ratio of the maximum thrusts obtained from experiment and theoretical prediction, under this condition was estimated as 70%.

  18. Flow interaction in the combustor-diffusor system of industrial gas turbines

    SciTech Connect

    Agrawal, A.K.; Kapat, J.S.; Yang, T.

    1996-05-01

    This paper presents an experimental/computational study of cold flow in the combustor-diffuser system of industrial gas turbines to address issues relating to flow interactions and pressure losses in the pre- and dump diffusers. The present configuration with can annular combustors differs substantially from the aircraft engines which typically use a 360 degree annular combustor. Experiments were conducted in a one-third scale, annular 360-degree model using several can combustors equispaced around the turbine axis. A 3-D computational fluid dynamics analysis employing the multidomain procedure was performed to supplement the flow measurements. The measured data correlated well with the computations. The airflow in the dump diffuser adversely affected the prediffuser flow by causing it to accelerate in the outer region at the prediffuser exit. This phenomenon referred to as the sink-effect also caused a large fraction of the flow to bypass much of the dump diffuser and go directly from the prediffuser exit to the bypass air holes on the combustor casing, thereby, rendering the dump diffuser ineffective in diffusing the flow. The dump diffuser was occupied by a large recirculation region which dissipated the flow kinetic energy. Approximately 1.2 dynamic head at the prediffuser inlet was lost in the combustor-diffuser system; much of it in the dump diffuser where the fluid passed through the narrow gaps and pathways. Strong flow interactions in the combustor-diffuser system indicate the need for design modifications which could not be addressed by empirical correlations based on simple flow configurations.

  19. Coal-fired MHD combustor development project: Phase IIIB. First quarterly technical progress report, 13 January-30 April 1982

    SciTech Connect

    1982-05-20

    The first quarterly technical progress report of the Coal-Fired MHD Combustor Development Project (Phase IIIB) presents the accomplishments during the period 13 January to 30 April, 1982. The scope of work covered by this quarterly report relates to those tasks associated with preparing the TRW 20 MW/sub t/ MHD coal combustor for delivery to AERL for integrated power tests and the work associated with the preliminary design of a 50 MW/sub t/ coal-fired combustor. Progress during this reporting period is described. All new 20 MW/sub t/ hardware was designed and fabricated. Interface coordination meetings were conducted with AERL and DOE. Interface control drawings were completed and a 20 MW/sub t/ coal combustion User's manual was delivered to AERL. The User's manual contained a shipping plan, a crew training plan, an assembly manual, interface documentation and recommended operating procedures. Facility/combustor set-up was completed and the pre-delivery 20 MW/sub t/ coal combustor qualification test series was completed. The 50 MW/sub t/ coal-fired MHD combustor preliminary designs were finalized and the DOE preliminary design review (PDR) was successfully completed.

  20. Interim Service ISDN Satellite (ISIS) hardware experiment design for advanced ISDN satellite design and experiments

    NASA Technical Reports Server (NTRS)

    Pepin, Gerard R.

    1992-01-01

    The Interim Service Integrated Services Digital Network (ISDN) Satellite (ISIS) Hardware Experiment Design for Advanced Satellite Designs describes the design of the ISDN Satellite Terminal Adapter (ISTA) capable of translating ISDN protocol traffic into time division multiple access (TDMA) signals for use by a communications satellite. The ISTA connects the Type 1 Network Termination (NT1) via the U-interface on the line termination side of the CPE to the V.35 interface for satellite uplink. The same ISTA converts in the opposite direction the V.35 to U-interface data with a simple switch setting.

  1. LDV measurements in an annular combustor model. M.S. Thesis

    NASA Technical Reports Server (NTRS)

    Barron, Dean A.

    1986-01-01

    The design and setup of a Laser Doppler Velocimeter (LDV) system used to take velocity measurements in an annular combustor model are covered. The annular combustor model is of contemporary design using 60 degree flat vane swirlers, producing a strong recirculation zone. Detailed measurements are taken of the swirler inlet air flow and of the downstream enclosed swirling flow. The laser system used is a two color, two component system set up in forward scatter. Detailed are some of the special considerations needed for LDV use in the confined turbulent flow of the combustor model. The LDV measurements in a single swirler rig indicated that the flow changes radically in the first duct height. After this, a flow profile is set up and remains constant in shape. The magnitude of the velocities gradually decays due to viscous damping.

  2. Performance of a Model Rich Burn-quick Mix-lean Burn Combustor at Elevated Temperature and Pressure

    NASA Technical Reports Server (NTRS)

    Peterson, Christopher O.; Sowa, William A.; Samuelsen, G. S.

    2002-01-01

    As interest in pollutant emission from stationary and aero-engine gas turbines increases, combustor engineers must consider various configurations. One configuration of increasing interest is the staged, rich burn - quick mix - lean burn (RQL) combustor. This report summarizes an investigation conducted in a recently developed high pressure gas turbine combustor facility. The model RQL combustor was plenum fed and modular in design. The fuel used for this study is Jet-A which was injected from a simplex atomizer. Emission (CO2, CO, O2, UHC, NOx) measurements were obtained using a stationary exit plane water-cooled probe and a traversing water-cooled probe which sampled from the rich zone exit and the lean zone entrance. The RQL combustor was operated at inlet temperatures ranging from 367 to 700 K, pressures ranging from 200 to 1000 kPa, and combustor reference velocities ranging from 10 to 20 m/s. Variations were also made in the rich zone and lean zone equivalence ratios. Several significant trends were observed. NOx production increased with reaction temperature, lean zone equivalence ratio and residence time and decreased with increased rich zone equivalence ratio. NOx production in the model RQL combustor increased to the 0.4 power with increased pressure. This correlation, compared to those obtained for non-staged combustors (0.5 to 0.7), suggests a reduced dependence on NOx on pressure for staged combustors. Emissions profiles suggest that rich zone mixing is not uniform and that the rich zone contributes on the order of 16 percent to the total NOx produced.

  3. Exploration of Advanced Probabilistic and Stochastic Design Methods

    NASA Technical Reports Server (NTRS)

    Mavris, Dimitri N.

    2003-01-01

    The primary objective of the three year research effort was to explore advanced, non-deterministic aerospace system design methods that may have relevance to designers and analysts. The research pursued emerging areas in design methodology and leverage current fundamental research in the area of design decision-making, probabilistic modeling, and optimization. The specific focus of the three year investigation was oriented toward methods to identify and analyze emerging aircraft technologies in a consistent and complete manner, and to explore means to make optimal decisions based on this knowledge in a probabilistic environment. The research efforts were classified into two main areas. First, Task A of the grant has had the objective of conducting research into the relative merits of possible approaches that account for both multiple criteria and uncertainty in design decision-making. In particular, in the final year of research, the focus was on the comparison and contrasting between three methods researched. Specifically, these three are the Joint Probabilistic Decision-Making (JPDM) technique, Physical Programming, and Dempster-Shafer (D-S) theory. The next element of the research, as contained in Task B, was focused upon exploration of the Technology Identification, Evaluation, and Selection (TIES) methodology developed at ASDL, especially with regards to identification of research needs in the baseline method through implementation exercises. The end result of Task B was the documentation of the evolution of the method with time and a technology transfer to the sponsor regarding the method, such that an initial capability for execution could be obtained by the sponsor. Specifically, the results of year 3 efforts were the creation of a detailed tutorial for implementing the TIES method. Within the tutorial package, templates and detailed examples were created for learning and understanding the details of each step. For both research tasks, sample files and

  4. Sandia Advanced MEMS Design Tools, Version 2.2.5

    SciTech Connect

    Yarberry, Victor; Allen, James; Lantz, Jeffery; Priddy, Brian; & Westling, Belinda

    2010-01-19

    The Sandia National Laboratories Advanced MEMS Design Tools, Version 2.2.5, is a collection of menus, prototype drawings, and executables that provide significant productivity enhancements when using AutoCAD to design MEMS components. This release is designed for AutoCAD 2000i, 2002, or 2004 and is supported under Windows NT 4.0, Windows 2000, or XP. SUMMiT V (Sandia Ultra planar Multi level MEMS Technology) is a 5 level surface micromachine fabrication technology, which customers internal and external to Sandia can access to fabricate prototype MEMS devices. This CD contains an integrated set of electronic files that: a) Describe the SUMMiT V fabrication process b) Facilitate the process of designing MEMS with the SUMMiT process (prototype file, Design Rule Checker, Standard Parts Library) New features in this version: AutoCAD 2004 support has been added. SafeExplode ? a new feature that explodes blocks without affecting polylines (avoids exploding polylines into objects that are ignored by the DRC and Visualization tools). Layer control menu ? a pull-down menu for selecting layers to isolate, freeze, or thaw. Updated tools: A check has been added to catch invalid block names. DRC features: Added username/password validation, added a method to update the user?s password. SNL_DRC_WIDTH ? a value to control the width of the DRC error lines. SNL_BIAS_VALUE ? a value use to offset selected geometry SNL_PROCESS_NAME ? a value to specify the process name Documentation changes: The documentation has been updated to include the new features. While there exist some files on the CD that are used in conjunction with software package AutoCAD, these files are not intended for use independent of the CD. Note that the customer must purchase his/her own copy of AutoCAD to use with these files.

  5. Automatic differentiation of advanced CFD codes for multidisciplinary design

    SciTech Connect

    Bischof, C.; Corliss, G.; Griewank, A.; Green, L.; Haigler, K.; Newman, P.

    1992-12-31

    Automated multidisciplinary design of aircraft and other flight vehicles requires the optimization of complex performance objectives with respect to a number of design parameters and constraints. The effect of these independent design variables on the system performance criteria can be quantified in terms of sensitivity derivatives which must be calculated and propagated by the individual discipline simulation codes. Typical advanced CFD analysis codes do not provide such derivatives as part of a flow solution; these derivatives are very expensive to obtain by divided (finite) differences from perturbed solutions. It is shown here that sensitivity derivatives can be obtained accurately and efficiently using the ADIFOR source translator for automatic differentiation. In particular, it is demonstrated that the 3-D, thin-layer Navier-Stokes, multigrid flow solver called TLNS3D is amenable to automatic differentiation in the forward mode even with its implicit iterative solution algorithm and complex turbulence modeling. It is significant that using computational differentiation, consistent discrete nongeometric sensitivity derivatives have been obtained from an aerodynamic 3-D CFD code in a relatively short time, e.g. O(man-week) not O(man-year).

  6. Automatic differentiation of advanced CFD codes for multidisciplinary design

    SciTech Connect

    Bischof, C.; Corliss, G.; Griewank, A. ); Green, L.; Haigler, K.; Newman, P. . Langley Research Center)

    1992-01-01

    Automated multidisciplinary design of aircraft and other flight vehicles requires the optimization of complex performance objectives with respect to a number of design parameters and constraints. The effect of these independent design variables on the system performance criteria can be quantified in terms of sensitivity derivatives which must be calculated and propagated by the individual discipline simulation codes. Typical advanced CFD analysis codes do not provide such derivatives as part of a flow solution; these derivatives are very expensive to obtain by divided (finite) differences from perturbed solutions. It is shown here that sensitivity derivatives can be obtained accurately and efficiently using the ADIFOR source translator for automatic differentiation. In particular, it is demonstrated that the 3-D, thin-layer Navier-Stokes, multigrid flow solver called TLNS3D is amenable to automatic differentiation in the forward mode even with its implicit iterative solution algorithm and complex turbulence modeling. It is significant that using computational differentiation, consistent discrete nongeometric sensitivity derivatives have been obtained from an aerodynamic 3-D CFD code in a relatively short time, e.g. O(man-week) not O(man-year).

  7. An advanced teleoperator control system - Design and evaluation

    NASA Technical Reports Server (NTRS)

    Lee, Sukhan; Lee, Hahk S.

    1992-01-01

    The design goal of an advanced teleoperator control system is twofold: 1) to allow the operator's manual control to be robust to system nonlinearities such as time delays and operator's control errors, and 2) to support the high performance of teleoperation while reducing the operator's control burden by providing the master and slave arms with desirable dynamic properties and by allowing the slave arm to automatically perform such control tasks as compliance and force control in the form of task sharing. The authors present a novel teleoperator control system achieving the above design goal by taking the following into consideration: the human dynamics involved in generating control command based on visual and forced feedback is modeled and incorporated into the controller design and evaluation; the dynamic characteristics of slave and master arms are actively modified in such a way as to implement the desirable dynamic characteristics; and the force feedback is redefined in terms of the combination of opposition and force discrepancies in order to establish the required man/machine dynamic coordination under shared control. The proposed control system with human dynamics in the control loop is simulated and compared with a number of conventional methods in the presence of human control errors and time delays.

  8. Aerospace Engineering Systems and the Advanced Design Technologies Testbed Experience

    NASA Technical Reports Server (NTRS)

    VanDalsem, William R.; Livingston, Mary E.; Melton, John E.; Torres, Francisco J.; Stremel, Paul M.

    1999-01-01

    Continuous improvement of aerospace product development processes is a driving requirement across much of the aerospace community. As up to 90% of the cost of an aerospace product is committed during the first 10% of the development cycle, there is a strong emphasis on capturing, creating, and communicating better information (both requirements and performance) early in the product development process. The community has responded by pursuing the development of computer-based systems designed to enhance the decision-making capabilities of product development individuals and teams. Recently, the historical foci on sharing the geometrical representation and on configuration management are being augmented: 1) Physics-based analysis tools for filling the design space database; 2) Distributed computational resources to reduce response time and cost; 3) Web-based technologies to relieve machine-dependence; and 4) Artificial intelligence technologies to accelerate processes and reduce process variability. The Advanced Design Technologies Testbed (ADTT) activity at NASA Ames Research Center was initiated to study the strengths and weaknesses of the technologies supporting each of these trends, as well as the overall impact of the combination of these trends on a product development event. Lessons learned and recommendations for future activities are reported.

  9. Design related aspects in advanced nuclear fission plants

    NASA Astrophysics Data System (ADS)

    Hoffelner, Wolfgang

    2011-02-01

    Important issues to be considered for design of future reactors are: extrapolation of stress rupture data, creep-fatigue, negligible creep, damage monitoring. The paper highlights some new developments taking examples from a martensitic steel (mod 9% Cr), oxide dispersion strengthened (ODS) steels and nickel-base superalloys. Traditional approaches to extrapolation of (thermal) stress rupture data like Larson-Miller Parameter or Monkman-Grant rule seem to be valid concepts also for advanced reactors. However, a significant influence of cyclic softening on creep rates and stress rupture data can be expected as shown for grade 91. This is particularly true for creep-fatigue interactions. Based on cyclic stress-strain behaviour it is also possible to get very good life-time predictions under creep-fatigue with a strain range separation (inelastic fatigue and creep ranges) technique which could replace the currently used linear life fraction rule. Results from in-beam irradiation creep reveal no significant influence of dispersoid size. It can be assumed that irradiation creep is a matrix property. Finally it is shown that micro-sample testing of exposed material could be used as an advanced method for damage assessment in future nuclear power plants.

  10. Advanced Single-Aisle Transport Propulsion Design Options Revisited

    NASA Technical Reports Server (NTRS)

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

    2013-01-01

    Future propulsion options for advanced single-aisle transports have been investigated in a number of previous studies by the authors. These studies have examined the system level characteristics of aircraft incorporating ultra-high bypass ratio (UHB) turbofans (direct drive and geared) and open rotor engines. During the course of these prior studies, a number of potential refinements and enhancements to the analysis methodology and assumptions were identified. This paper revisits a previously conducted UHB turbofan fan pressure ratio trade study using updated analysis methodology and assumptions. The changes incorporated have decreased the optimum fan pressure ratio for minimum fuel consumption and reduced the engine design trade-offs between minimizing noise and minimizing fuel consumption. Nacelle drag and engine weight are found to be key drivers in determining the optimum fan pressure ratio from a fuel efficiency perspective. The revised noise analysis results in the study aircraft being 2 to 4 EPNdB (cumulative) quieter due to a variety of reasons explained in the paper. With equal core technology assumed, the geared engine architecture is found to be as good as or better than the direct drive architecture for most parameters investigated. However, the engine ultimately selected for a future advanced single-aisle aircraft will depend on factors beyond those considered here.

  11. Design and analysis of advanced flight planning concepts

    NASA Technical Reports Server (NTRS)

    Sorensen, John A.

    1987-01-01

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

  12. The role of reactant unmixedness, strain rate, and length scale on premixed combustor performance

    SciTech Connect

    Samuelsen, S.; LaRue, J.; Vilayanur, S.; Guillaume, D.

    1995-12-31

    Lean premixed combustion provides a means to reduce pollutant formation and increase combustion efficiency. However, fuel-air mixing is rarely uniform in space and time. This nonuniformity in concentration will lead to relative increases in pollutant formation and decreases in combustion efficiency. The nonuniformity of the concentration at the exit of the premixer has been defined by Lyons (1981) as the ``unmixedness.`` Although turbulence properties such as length scales and strain rate are known to effect unmixedness, the exact relationship is unknown. Evaluating this relationship and the effect of unmixedness in premixed combustion on pollutant formation and combustion efficiency are an important part of the overall goal of US Department of Energy`s Advanced Turbine System (ATS) program and are among the goals of the program described herein. The information obtained from ATS is intended to help to develop and commercialize gas turbines. The contributions to the program which the University of California (Irvine) Combustion Lab (UCICL) will provide are: (1) establish the relationship of inlet unmixedness, length scales, and mean strain rate to performance, (2) determine the optimal levels of inlet unmixedness, length scales, and mean strain rates to maximize combustor performance, and (3) identify efficient premixing methods for achieving the necessary inlet conditions. The program during this reporting period is focused on developing a means to measure and qualify different degrees of temporal and spatial unmixedness. Laser diagnostic methods for planer unmixedness measurements are being developed and preliminary results are presented herein. These results will be used to (1), aid in the design of experimental premixers, and (2), determine the unmixedness which will be correlated with the emissions of the combustor. This measure of unmixedness coupled with length scale, strain rate and intensity information is required to attain the UCI goals.

  13. Status and design of the Advanced Photon Source control system

    SciTech Connect

    McDowell, W.; Knott, M.; Lenkszus, F.; Kraimer, M.; Arnold, N.; Daly, R.

    1993-06-01

    This paper presents the current status of the Advanced Photon Source (APS) control system. It will discuss the design decisions which led us to use industrial standards and collaborations with other laboratories to develop the APS control system. The system uses high performance graphic workstations and the X-windows Graphical User Interface (GUI) at the operator interface level. It connects to VME/VXI-based microprocessors at the field level using TCP/IP protocols over high performance networks. This strategy assures the flexibility and expansibility of the control system. A defined interface between the system components will allow the system to evolve with the direct addition of future, improved equipment and new capabilities.

  14. Status and design of the Advanced Photon Source control system

    SciTech Connect

    McDowell, W.; Knott, M.; Lenkszus, F.; Kraimer, M.; Arnold, N.; Daly, R.

    1993-01-01

    This paper presents the current status of the Advanced Photon Source (APS) control system. It will discuss the design decisions which led us to use industrial standards and collaborations with other laboratories to develop the APS control system. The system uses high performance graphic workstations and the X-windows Graphical User Interface (GUI) at the operator interface level. It connects to VME/VXI-based microprocessors at the field level using TCP/IP protocols over high performance networks. This strategy assures the flexibility and expansibility of the control system. A defined interface between the system components will allow the system to evolve with the direct addition of future, improved equipment and new capabilities.

  15. High-Pressure Design of Advanced BN-Based Materials.

    PubMed

    Kurakevych, Oleksandr O; Solozhenko, Vladimir L

    2016-10-20

    The aim of the present review is to highlight the state of the art in high-pressure design of new advanced materials based on boron nitride. Recent experimental achievements on the governing phase transformation, nanostructuring and chemical synthesis in the systems containing boron nitride at high pressures and high temperatures are presented. All these developments allowed discovering new materials, e.g., ultrahard nanocrystalline cubic boron nitride (nano-cBN) with hardness comparable to diamond, and superhard boron subnitride B13N₂. Thermodynamic and kinetic aspects of high-pressure synthesis are described based on the data obtained by in situ and ex situ methods. Mechanical and thermal properties (hardness, thermoelastic equations of state, etc.) are discussed. New synthetic perspectives, combining both soft chemistry and extreme pressure-temperature conditions are considered.

  16. Frequency Domain Analysis of a Gas Fired Mechanically Valved Pulse Combustor

    NASA Astrophysics Data System (ADS)

    Neumeier, Yedidia

    1993-01-01

    This study presents an analysis of a mechanically valved pulse combustor in the frequency domain. The pulse combustor is treated as a feedback system. The forward branch of the system consists of the acoustic resonator, while the feedback loop consists of the combustion heat release process and the heat loss through the pulse combustor walls. The model of the acoustic resonator is based upon an analysis of the conservation equation for the combustion chamber energy oscillations and the tail pipe acoustics. The present study utilizes a phenomenological approach to model the periodic heat release process in the combustor. The model accounts for the mixing of cold reactants with hot products, flame extinction due to high velocities during the injection time, and the kinetics of the chemical reaction. The results of this study indicate that a high periodic heat transfer must take place in the combustion zone of mechanically valved pulse combustors. The intensity of this oscillating heat transfer is an order of magnitude larger than has been observed until the present study. The results imply that the unsteady heat transfer contributes vital feedback that stabilizes the limit cycle of the pulse combustor. The study was extended to include preliminary experimental evidence for the existence of a very high wall heat losses in the combustion zone, as predicted by the model. No model of pulse combustor that fails to account for unsteady heat transfer in the combustion zone can be considered fully accurate. A calibration procedure is developed to optimize the model prediction. This calibration process is oriented to provide an accurate prediction of the important parameters; namely, the pressure level and the operating frequency, at the cost of less accuracy in predicting relatively less important parameters. The model developed in the study has been used to develop a software package application for design and analysis of pulse combustors. The use of the software for pulse

  17. Estimating the uncertainty in thermochemical calculations for oxygen-hydrogen combustors

    NASA Astrophysics Data System (ADS)

    Sims, Joseph David

    The thermochemistry program CEA2 was combined with the statistical thermodynamics program PAC99 in a Monte Carlo simulation to determine the uncertainty in several CEA2 output variables due to uncertainty in thermodynamic reference values for the reactant and combustion species. In all, six typical performance parameters were examined, along with the required intermediate calculations (five gas properties and eight stoichiometric coefficients), for three hydrogen-oxygen combustors: a main combustor, an oxidizer preburner and a fuel preburner. The three combustors were analyzed in two different modes: design mode, where, for the first time, the uncertainty in thermodynamic reference values---taken from the literature---was considered (inputs to CEA2 were specified and so had no uncertainty); and data reduction mode, where inputs to CEA2 did have uncertainty. The inputs to CEA2 were contrived experimental measurements that were intended to represent the typical combustor testing facility. In design mode, uncertainties in the performance parameters were on the order of 0.1% for the main combustor, on the order of 0.05% for the oxidizer preburner and on the order of 0.01% for the fuel preburner. Thermodynamic reference values for H2O were the dominant sources of uncertainty, as was the assigned enthalpy for liquid oxygen. In data reduction mode, uncertainties in performance parameters increased significantly as a result of the uncertainties in experimental measurements compared to uncertainties in thermodynamic reference values. Main combustor and fuel preburner theoretical performance values had uncertainties of about 0.5%, while the oxidizer preburner had nearly 2%. Associated experimentally-determined performance values for all three combustors were 3% to 4%. The dominant sources of uncertainty in this mode were the propellant flowrates. These results only apply to hydrogen-oxygen combustors and should not be generalized to every propellant combination. Species for

  18. The Advanced Technology Solar Telescope: design and early construction

    NASA Astrophysics Data System (ADS)

    McMullin, Joseph P.; Rimmele, Thomas R.; Keil, Stephen L.; Warner, Mark; Barden, Samuel; Bulau, Scott; Craig, Simon; Goodrich, Bret; Hansen, Eric; Hegwer, Steve; Hubbard, Robert; McBride, William; Shimko, Steve; Wöger, Friedrich; Ditsler, Jennifer

    2012-09-01

    The National Solar Observatory’s (NSO) Advanced Technology Solar Telescope (ATST) is the first large U.S. solar telescope accessible to the worldwide solar physics community to be constructed in more than 30 years. The 4-meter diameter facility will operate over a broad wavelength range (0.35 to 28 μm ), employing adaptive optics systems to achieve diffraction limited imaging and resolve features approximately 20 km on the Sun; the key observational parameters (collecting area, spatial resolution, spectral coverage, polarization accuracy, low scattered light) enable resolution of the theoretically-predicted, fine-scale magnetic features and their dynamics which modulate the radiative output of the sun and drive the release of magnetic energy from the Sun’s atmosphere in the form of flares and coronal mass ejections. In 2010, the ATST received a significant fraction of its funding for construction. In the subsequent two years, the project has hired staff and opened an office on Maui. A number of large industrial contracts have been placed throughout the world to complete the detailed designs and begin constructing the major telescope subsystems. These contracts have included the site development, AandE designs, mirrors, polishing, optic support assemblies, telescope mount and coudé rotator structures, enclosure, thermal and mechanical systems, and high-level software and controls. In addition, design development work on the instrument suite has undergone significant progress; this has included the completion of preliminary design reviews (PDR) for all five facility instruments. Permitting required for physically starting construction on the mountaintop of Haleakalā, Maui has also progressed. This paper will review the ATST goals and specifications, describe each of the major subsystems under construction, and review the contracts and lessons learned during the contracting and early construction phases. Schedules for site construction, key factory testing of

  19. Exhaust gas measurements in a propane fueled swirl stabilized combustor

    NASA Technical Reports Server (NTRS)

    Aanad, M. S.

    1982-01-01

    Exhaust gas temperature, velocity, and composition are measured and combustor efficiencies are calculated in a lean premixed swirl stabilized laboratory combustor. The radial profiles of the data between the co- and the counter swirl cases show significant differences. Co-swirl cases show evidence of poor turbulent mixing across the combustor in comparison to the counter-swirl cases. NO sub x levels are low in the combustor but substantial amounts of CO are present. Combustion efficiencies are low and surprisingly constant with varying outer swirl in contradiction to previous results under a slightly different inner swirl condition. This difference in the efficiency trends is expected to be a result of the high sensitivity of the combustor to changes in the inner swirl. Combustor operation is found to be the same for propane and methane fuels. A mechanism is proposed to explain the combustor operation and a few important characteristics determining combustor efficiency are identified.

  20. Emission Characteristics of A P and W Axially Staged Sector Combustor

    NASA Technical Reports Server (NTRS)

    He, Zhuohui J.; Wey, Changlie; Chang, Clarence T.; Lee, Chi Ming; Surgenor, Angela D.; Kopp-Vaughan, Kristin; Cheung, Albert

    2016-01-01

    Emission characteristics of a three-cup P and W Axially Controlled Stoichiometry (ACS) sector combustor are reported in this article. Multiple injection points and fuel staging strategies are used in this combustor design. Pilot-stage injectors are located on the front dome plate of the combustor, and main-stage injectors are positioned on the top and bottom of the combustor liners downstream. Low power configuration uses only pilot-stage injectors. Main-stage injectors are added to high power configuration to help distribute fuel more evenly and achieve overall lean burn yielding very low NOx emissions. Combustion efficiencies at four ICAO LTO conditions were all above 99%. Three EINOx emissions correlation equations were developed based on the experimental data to describe the NOx emission trends of this combustor concept. For the 7% and 30% engine power conditions, NOx emissions are obtained with the low power configuration, and the EINOx values are 6.16 and 6.81. The high power configuration was used to assess 85% and 100% engine power NOx emissions, with measured EINOx values of 4.58 and 7.45, respectively. The overall landing-takeoff cycle NOx emissions are about 12% relative to ICAO CAEP/6 level.