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Sample records for aircraft engine inlet

  1. Cooling Air Inlet and Exit Geometries on Aircraft Engine Installations

    NASA Technical Reports Server (NTRS)

    Katz, Joseph; Corsiglia, Victor R.; Barlow, Philip R.

    1982-01-01

    A semispan wing and nacelle of a typical general aviation twin-engine aircraft was tested to evaluate the cooling capability and drag or several nacelle shapes; the nacelle shapes included cooling air inlet and exit variations. The tests were conducted in the Ames Research Center 40 x 80-ft Wind Tunnel. It was found that the cooling air inlet geometry of opposed piston engine installations has a major effect on inlet pressure recovery, but only a minor effect on drag. Exit location showed large effect on drag, especially for those locations on the sides of the nacelle where the suction characteristics were based on interaction with the wing surface pressures.

  2. Fiber optics for aircraft engine/inlet control

    NASA Technical Reports Server (NTRS)

    Baumbick, R. J.

    1981-01-01

    NASA programs that focus on the use of fiber optics for aircraft engine/inlet control are reviewed. Fiber optics for aircraft control is attractive because of its inherent immunity to EMI and RFI noise. Optical signals can be safely transmitted through areas that contain flammable or explosive materials. The use of optics also makes remote sensing feasible by eliminating the need for electrical wires to be connected between sensors and computers. Using low-level optical signals to control actuators is also feasible when power is generated at the actuator. Each application of fiber optics for aircraft control has different requirements for both the optical cables and the optical connectors. Sensors that measure position and speed by using slotted plates can use lossy cables and bundle connectors if data transfer is in the parallel mode. If position and speed signals are multiplexed, cable and connector requirements change. Other sensors that depend on changes in transmission through materials require dependable characteristics of both the optical cables and the optical connectors. A variety of sensor types are reviewed, including rotary position encoders, tachometers, temperature sensors, and blade tip clearance sensors for compressors and turbines. Research on a gallium arsenide photoswitch for optically switched actuators that operate at 250 C is also described.

  3. A One Dimensional, Time Dependent Inlet/Engine Numerical Simulation for Aircraft Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Garrard, Doug; Davis, Milt, Jr.; Cole, Gary

    1999-01-01

    The NASA Lewis Research Center (LeRC) and the Arnold Engineering Development Center (AEDC) have developed a closely coupled computer simulation system that provides a one dimensional, high frequency inlet/engine numerical simulation for aircraft propulsion systems. The simulation system, operating under the LeRC-developed Application Portable Parallel Library (APPL), closely coupled a supersonic inlet with a gas turbine engine. The supersonic inlet was modeled using the Large Perturbation Inlet (LAPIN) computer code, and the gas turbine engine was modeled using the Aerodynamic Turbine Engine Code (ATEC). Both LAPIN and ATEC provide a one dimensional, compressible, time dependent flow solution by solving the one dimensional Euler equations for the conservation of mass, momentum, and energy. Source terms are used to model features such as bleed flows, turbomachinery component characteristics, and inlet subsonic spillage while unstarted. High frequency events, such as compressor surge and inlet unstart, can be simulated with a high degree of fidelity. The simulation system was exercised using a supersonic inlet with sixty percent of the supersonic area contraction occurring internally, and a GE J85-13 turbojet engine.

  4. Active control of aircraft engine inlet noise using compact sound sources and distributed error sensors

    NASA Technical Reports Server (NTRS)

    Burdisso, Ricardo (Inventor); Fuller, Chris R. (Inventor); O'Brien, Walter F. (Inventor); Thomas, Russell H. (Inventor); Dungan, Mary E. (Inventor)

    1994-01-01

    An active noise control system using a compact sound source is effective to reduce aircraft engine duct noise. The fan noise from a turbofan engine is controlled using an adaptive filtered-x LMS algorithm. Single multi channel control systems are used to control the fan blade passage frequency (BPF) tone and the BPF tone and the first harmonic of the BPF tone for a plane wave excitation. A multi channel control system is used to control any spinning mode. The multi channel control system to control both fan tones and a high pressure compressor BPF tone simultaneously. In order to make active control of turbofan inlet noise a viable technology, a compact sound source is employed to generate the control field. This control field sound source consists of an array of identical thin, cylindrically curved panels with an inner radius of curvature corresponding to that of the engine inlet. These panels are flush mounted inside the inlet duct and sealed on all edges to prevent leakage around the panel and to minimize the aerodynamic losses created by the addition of the panels. Each panel is driven by one or more piezoelectric force transducers mounted on the surface of the panel. The response of the panel to excitation is maximized when it is driven at its resonance; therefore, the panel is designed such that its fundamental frequency is near the tone to be canceled, typically 2000-4000 Hz.

  5. Active control of aircraft engine inlet noise using compact sound sources and distributed error sensors

    NASA Technical Reports Server (NTRS)

    Burdisso, Ricardo (Inventor); Fuller, Chris R. (Inventor); O'Brien, Walter F. (Inventor); Thomas, Russell H. (Inventor); Dungan, Mary E. (Inventor)

    1996-01-01

    An active noise control system using a compact sound source is effective to reduce aircraft engine duct noise. The fan noise from a turbofan engine is controlled using an adaptive filtered-x LMS algorithm. Single multi channel control systems are used to control the fan blade passage frequency (BPF) tone and the BPF tone and the first harmonic of the BPF tone for a plane wave excitation. A multi channel control system is used to control any spinning mode. The multi channel control system to control both fan tones and a high pressure compressor BPF tone simultaneously. In order to make active control of turbofan inlet noise a viable technology, a compact sound source is employed to generate the control field. This control field sound source consists of an array of identical thin, cylindrically curved panels with an inner radius of curvature corresponding to that of the engine inlet. These panels are flush mounted inside the inlet duct and sealed on all edges to prevent leakage around the panel and to minimize the aerodynamic losses created by the addition of the panels. Each panel is driven by one or more piezoelectric force transducers mounted on the surface of the panel. The response of the panel to excitation is maximized when it is driven at its resonance; therefore, the panel is designed such that its fundamental frequency is near the tone to be canceled, typically 2000-4000 Hz.

  6. Inlet-engine matching for SCAR including application of a bicone variable geometry inlet. [Supersonic Cruise Aircraft Research

    NASA Technical Reports Server (NTRS)

    Wasserbauer, J. F.; Gerstenmaier, W. H.

    1978-01-01

    Airflow characteristics of variable cycle engines (VCE) designed for Mach 2.32 can have transonic airflow requirements as high as 1.6 times the cruise airflow. This is a formidable requirement for conventional, high performance, axisymmetric, translating centerbody mixed compression inlets. An alternate inlet is defined where the second cone of a two cone centerbody collapses to the initial cone angle to provide a large off-design airflow capability, and incorporates modest centerbody translation to minimize spillage drag. Estimates of transonic spillage drag are competitive with those of conventional translating centerbody inlets. The inlet's cruise performance exhibits very low bleed requirements with good recovery and high angle of attack capability.

  7. Apparatus and Method for Measuring Air Temperature Ahead of an Aircraft for Controlling a Variable Inlet/Engine Assembly

    NASA Technical Reports Server (NTRS)

    Gary, Bruce L. (Inventor)

    2001-01-01

    The apparatus and method employ remote sensing to measure the air temperature a sufficient distance ahead of the aircraft to allow time for a variable inlet/engine assembly to be reconfigured in response to the measured temperature, to avoid inlet unstart and/or engine compressor stall. In one embodiment, the apparatus of the invention has a remote sensor for measuring at least one air temperature ahead of the vehicle and an inlet control system for varying the inlet. The remote sensor determines a change in temperature value using at least one temperature measurement and prior temperature measurements corresponding to the location of the aircraft. The control system uses the change in air temperature value to vary the inlet configuration to maintain the position of the shock wave during the arrival of the measured air in the inlet. In one embodiment, the method of the invention includes measuring at least one air temperature ahead of the vehicle, determining an air temperature at the vehicle from prior air temperature measurements, determining a change in temperature value using the air temperature at the vehicle and the at least one air temperature measurement ahead of the vehicle, and using the change in temperature value to-reposition the airflow inlet, to cause the shock wave to maintain substantially the same position within the inlet as the airflow temperature changes within the inlet.

  8. Inlet Engineering Toolbox

    DTIC Science & Technology

    2014-10-31

    ADDRESS(ES) U.S. Army Engineer Research and Development Center,CIRP - The Coastal Inlets Research Program,3909 Halls Ferry Road,Vicksburg,MS,39180... Coastal Inlets Research Program Inlet Engineering Toolbox The Inlet Engineering Toolbox (IET) Work Unit develops desktop PC and web-based tools to...aid in studies of the consequences of engineering actions at coastal inlets and adjacent beaches. District scientists and engineers need rapid

  9. Advanced Methods for Aircraft Engine Thrust and Noise Benefits: Nozzle-Inlet Flow Analysis

    NASA Technical Reports Server (NTRS)

    Gilinsky, Mikhail; Morgan, Morris H.; Hardin, Jay C.; Mosiane, Lotlamoreng; Kaushal, Patel; Blankson, Isaiah M.

    2000-01-01

    In this project, we continue to develop the previous joint research between the Fluid Mechanics and Acoustics Laboratory (FM&AL) at Hampton University (HU) and the Jet Noise Team (JNT) at the NASA Langley Research Center (NASA LaRC). The FM&AL was established at Hampton University in June of 1996 and has conducted research under two NASA grants: NAG-1-1835 (1996-99), and NAG-1-1936 (1997-00). In addition, the FM&AL has jointly conducted research with the Central AeroHydrodynamics Institute (TsAGI, Moscow) in Russia under a Civilian Research and Development Foundation (CRDF) grant #RE2-136 (1996-99). The goals of the FM&AL programs are twofold: (1) to improve the working efficiency of the FM&AUs team in generating new innovative ideas and in conducting research in the field of fluid dynamics and acoustics, basically for improvement of supersonic and subsonic aircraft engines, and (2) to attract promising minority students to this research and training and, in cooperation with other HU departments, to teach them basic knowledge in Aerodynamics, Gas Dynamics, and Theoretical and Experimental Methods in Aeroacoustics and Computational Fluid Dynamics (CFD). The research at the HU FM&AL supports reduction schemes associated with the emission of engine pollutants for commercial aircraft and concepts for reduction of observables for military aircraft. These research endeavors relate to the goals of the NASA Strategic Enterprise in Aeronautics concerning the development of environmentally acceptable aircraft. It is in this precise area, where the US aircraft industry, academia, and Government are in great need of trained professionals and which is a high priority goal of the Minority University Research and Education (MUREP) Program, that the HU FM&AL can make its most important contribution. The main achievements for the reporting period in the development of concepts for noise reduction and improvement in efficiency for jet exhaust nozzles and inlets for aircraft engines

  10. Estimating Engine Airflow in Gas-Turbine Powered Aircraft with Clean and Distorted Inlet Flows

    NASA Technical Reports Server (NTRS)

    Williams, J. G.; Steenken, W. G.; Yuhas, A. J.

    1996-01-01

    The P404-GF-400 Powered F/A-18A High Alpha Research Vehicle (HARV) was used to examine the impact of inlet-generated total-pressure distortion on estimating levels of engine airflow. Five airflow estimation methods were studied. The Reference Method was a fan corrected airflow to fan corrected speed calibration from an uninstalled engine test. In-flight airflow estimation methods utilized the average, or individual, inlet duct static- to total-pressure ratios, and the average fan-discharge static-pressure to average inlet total-pressure ratio. Correlations were established at low distortion conditions for each method relative to the Reference Method. A range of distorted inlet flow conditions were obtained from -10 deg. to +60 deg. angle of attack and -7 deg. to +11 deg. angle of sideslip. The individual inlet duct pressure ratio correlation resulted in a 2.3 percent airflow spread for all distorted flow levels with a bias error of -0.7 percent. The fan discharge pressure ratio correlation gave results with a 0.6 percent airflow spread with essentially no systematic error. Inlet-generated total-pressure distortion and turbulence had no significant impact on the P404-GE400 engine airflow pumping. Therefore, a speed-flow relationship may provide the best airflow estimate for a specific engine under all flight conditions.

  11. The induction of water to the inlet air as a means of internal cooling in aircraft-engine cylinders

    NASA Technical Reports Server (NTRS)

    Rothrock, Addison M; Krsek, Alois, Jr; Jones, Anthony W

    1943-01-01

    Report presents the results of investigations conducted on a full-scale air-cooled aircraft-engine cylinder of 202-cubic inch displacement to determine the effects of internal cooling by water induction on the maximum permissible power and output of an internal-combustion engine. For a range of fuel-air and water-fuel ratios, the engine inlet pressure was increased until knock was detected aurally, the power was then decreased 7 percent holding the ratios constant. The data indicated that water was a very effective internal coolant, permitting large increases in engine power as limited by either knock or by cylinder temperatures.

  12. Advanced Methods for Aircraft Engine Thrust and Noise Benefits: Nozzle-Inlet Flow Analysis

    NASA Technical Reports Server (NTRS)

    Gilinsky, Mikhail; Morgan, Morris H.; Povitsky, Alex; Schkolnikov, Natalia; Njoroge, Norman; Coston, Calvin; Blankson, Isaiah M.

    2001-01-01

    The Fluid Mechanics and Acoustics Laboratory at Hampton University (HU/FM&AL) jointly with the NASA Glenn Research Center has conducted four connected subprojects under the reporting project. Basically, the HU/FM&AL Team has been involved in joint research with the purpose of theoretical explanation of experimental facts and creation of accurate numerical simulation techniques and prediction theory for solution of current problems in propulsion systems of interest to the NAVY and NASA agencies. This work is also supported by joint research between the NASA GRC and the Institute of Mechanics at Moscow State University (IM/MSU) in Russia under a CRDF grant. The research is focused on a wide regime of problems in the propulsion field as well as in experimental testing and theoretical and numerical simulation analyses for advanced aircraft and rocket engines. The FM&AL Team uses analytical methods, numerical simulations and possible experimental tests at the Hampton University campus. The fundamental idea uniting these subprojects is to use nontraditional 3D corrugated and composite nozzle and inlet designs and additional methods for exhaust jet noise reduction without essential thrust loss and even with thrust augmentation. These subprojects are: (1) Aeroperformance and acoustics of Bluebell-shaped and Telescope-shaped designs; (2) An analysis of sharp-edged nozzle exit designs for effective fuel injection into the flow stream in air-breathing engines: triangular-round, diamond-round and other nozzles; (3) Measurement technique improvement for the HU Low Speed Wind Tunnel; a new course in the field of aerodynamics, teaching and training of HU students; experimental tests of Mobius-shaped screws: research and training; (4) Supersonic inlet shape optimization. The main outcomes during this reporting period are: (l) Publications: The AIAA Paper #00-3170 was presented at the 36th AIAA/ASME/SAE/ASEE Joint Propulsion Conference, 17-19 June, 2000, Huntsville, AL. The AIAA

  13. Factors Affecting Inlet-Engine Compatibility During Aircraft Departures at High Angle of Attack for an F/A -18A Aircraft

    NASA Technical Reports Server (NTRS)

    Steenken, W. G.; Williams, J. G.; Yuhas, A. J.; Walsh, K. R.

    1999-01-01

    The F404-GE-400 engine powered F/A- 18A High Alpha Research Vehicle (HARV) was used to examine the quality of inlet airflow during departed flight maneuvers, that is, during flight outside the normal maneuvering envelope where control surfaces have little or no effectiveness. A series of six nose-left and six nose-right departures were initiated at Mach numbers between 0.3 and 0.4 at an altitude of 35 kft. The yaw rates at departure recovery were in the range of 40 to 90 degrees per second. Engine surges were encountered during three of the nose-left and one of the nose-right departures. Time-variant inlet-total-pressure distortion levels at the engine face were determined to not significantly exceed those measured at maximum angle-of-attack and - sideslip maneuvers during controlled flight. Surges as a result of inlet distortion levels were anticipated to initiate in the fan. Analysis revealed that the surges initiated in the compressor and were the result of a combination of high levels of inlet distortion and rapid changes in aircraft motion. These rapid changes in aircraft motion are indicative of a combination of engine mount and gyroscopic loads being applied to the engine structure that impact the aerodynamic stability of the compressor through changes in the rotor-to-case clearances.

  14. Water droplet impingement on airfoils and aircraft engine inlets for icing analysis

    NASA Technical Reports Server (NTRS)

    Papadakis, Michael; Elangovan, R.; Freund, George A., Jr.; Breer, Marlin D.

    1991-01-01

    This paper includes the results of a significant research program for verification of computer trajectory codes used in aircraft icing analysis. Experimental water droplet impingement data have been obtained in the NASA Lewis Research Center Icing Research Tunnel for a wide range of aircraft geometries and test conditions. The body whose impingement characteristics are required is covered at strategic locations by thin strips of moisture absorbing (blotter) paper and then exposed to an airstream containing a dyed-water spray cloud. Water droplet impingement data are extracted from the dyed blotter strips by measuring the optical reflectance of the dye deposit on the strips with an automated reflectometer. Impingement characteristics for all test geometries have also been calculated using two recently developed trajectory computer codes. Good agreement is obtained with experimental data. The experimental and analytical data show that maximum impingement efficiency and impingement limits increase with mean volumetric diameter for all geometries tested. For all inlet geometries tested, as the inlet mass flow is reduced, the maximum impingement efficiency is reduced and the location of the maximum impingement shifts toward the inlet inner cowl.

  15. Test-engine and inlet performance of an aircraft used for investigating flight effects on fan noise

    NASA Technical Reports Server (NTRS)

    Golub, R. A.; Preisser, J. S.

    1984-01-01

    As part of the NASA Flight Effects on Fan Noise Program, a Grumman OV-1B Mohawk aircraft was modified to carry a modified and instrumented Pratt & Whitney JT15D-1 turbofan engine. Onboard flight data, together with simultaneously measured farfield acoustic data, comprise a flight data base to which JT15D-1 static and wind-tunnel data are compared. The overall objective is to improve the ability to use ground-based facilities for the prediction of flight inlet radiated noise. This report describes the hardware and presents performance results for the research engine.

  16. Advanced Methods for Aircraft Engine Thrust and Noise Benefits: Nozzle-Inlet Flow Analysis

    NASA Technical Reports Server (NTRS)

    Morgan, Morris H., III; Gilinsky, Mikhail M.

    2004-01-01

    In this project on the first stage (2000-Ol), we continued to develop the previous joint research between the Fluid Mechanics and Acoustics Laboratory (FM&AL) at Hampton University (HU) and the Jet Noise Team (JNT) at the NASA Langley Research Center (NASA LaRC). At the second stage (2001-03), FM&AL team concentrated its efforts on solving of problems of interest to Glenn Research Center (NASA GRC), especially in the field of propulsion system enhancement. The NASA GRC R&D Directorate and LaRC Hyper-X Program specialists in a hypersonic technology jointly with the FM&AL staff conducted research on a wide region of problems in the propulsion field as well as in experimental testing and theoretical and numerical simulation analyses for advanced aircraft and rocket engines. The last year the Hampton University School of Engineering & Technology was awarded the NASA grant, for creation of the Aeropropulsion Center, and the FM&AL is a key team of the project fulfillment responsible for research in Aeropropulsion and Acoustics (Pillar I). This work is supported by joint research between the NASA GRC/ FM&AL and the Institute of Mechanics at Moscow State University (IMMSU) in Russia under a CRDF grant. The main areas of current scientific interest of the FM&AL include an investigation of the proposed and patented advanced methods for aircraft engine thrust and noise benefits. This is the main subject of our other projects, of which one is presented. The last year we concentrated our efforts to analyze three main problems: (a) new effective methods fuel injection into the flow stream in air-breathing engines; (b) new re-circulation method for mixing, heat transfer and combustion enhancement in propulsion systems and domestic industry application; (c) covexity flow The research is focused on a wide regime of problems in the propulsion field as well as in experimental testing and theoretical and numerical simulation analyses for advanced aircraft and rocket engines (see, for

  17. Theoretical evaluation of engine auxiliary inlet design for supersonic V/STOL aircraft

    NASA Technical Reports Server (NTRS)

    Boles, Michael A.; Heavner, Richard L.

    1988-01-01

    A higher order panel method is used to evaluate the potential flow of a two dimensional supersonic V/STOL inlet. A non-symmetric analytical inlet model is developed to closely match a wind tunnel model. The analytical inlet is analyzed for flow characteristics around the lower cowl lip and auxiliary inlets. The results are obtained from the output of a computer program that is based on the Hess Panel Method which determines source strengths of panels distributed over a three dimensional body. The analytical model was designed for the implementation of drooped/translated cowl lip and auxiliary inlets as flow improvement concepts. A 40 or 70 degree droop lip can be incorporated on the inlet to determine if these geometry modifications result in flow improvements which may reduce the propensity for flow separation on the interior portion of the lip. Auxiliary inlets are employed to decrease the mass flow over the inlet lip. Thus, the peak flow velocity is reduced at the lip which also lessens the likelihood of flow separation on the interior portion of the lip. A 2, 4, and 6 inch translated lip can be employed to also decrease mass flow over the inlet lower lip in the same manner as the auxiliary inlet. The performance results of the flow improvement concepts show that three possible inlet configurations provide a situation where separation is less likely to occur. A 70 degree droop lip maintains flow conditions such that attached flow over the lower cowl lip may exist for the entire angle of attack range studied. A 0 degree droop and translated lip combination provides similar results for the angle of attack range. The third configuration consists of a 0 degree droop and auxiliary inlet combination. This configuration provides slightly less favorable results than the other two, but still allows for conditions favorable to attached flow within the inlet.

  18. Theoretical evaluation of engine auxiliary inlet design for supersonic V/STOL aircraft

    NASA Technical Reports Server (NTRS)

    Boles, Michael A.; Heavner, Richard L.

    1991-01-01

    A higher order panel method is used to evaluate the potential flow of a 2-D supersonic V/STOL inlet. A nonsymmetric analytical inlet model is developed to closely match a wind tunnel model tested at NASA-Lewis. The analytical inlet used is analyzed for flow characteristics around the lower cowl lip and auxiliary inlets. The results for this analysis are obtained for the output of a computer program produced by the McDonnell Douglas Corp. This program is based on the Hess Panel Method which determines source strengths of panel distributed over a 3-D body. The analytical model was designed for the implementation of a drooped/translated cowl lip and auxiliary inlets as flow improvement concepts. A 40 or 70 deg droop lip can be incorporated on the inlet to determine if these geometry changes result in flow improvements which may reduce the propensity for flow separation on the interior portion of the lip. Auxiliary inlets are used to decrease the mass flow over the inlet lip; thus, the peak flow velocity is reduced at the lip which also lessens the likelihood of flow separation on the interior portion of the lip. A 2, 4, and 6 in. translated lip can be used to also decrease mass flow over the inlet lower lip in the same manner.

  19. Advanced Methods for Aircraft Engine Thrust and Noise Benefits: Nozzle-Inlet Flow Analysis

    NASA Technical Reports Server (NTRS)

    Morgan, Morris H.; Gilinsky, Mikhail; Patel, Kaushal; Coston, Calvin; Blankson, Isaiah M.

    2003-01-01

    The research is focused on a wide regime of problems in the propulsion field as well as in experimental testing and theoretical and numerical simulation analyses for advanced aircraft and rocket engines. Results obtained are based on analytical methods, numerical simulations and experimental tests at the NASA LaRC and Hampton University computer complexes and experimental facilities. The main objective of this research is injection, mixing and combustion enhancement in propulsion systems. The sub-projects in the reporting period are: (A) Aero-performance and acoustics of Telescope-shaped designs. The work included a pylon set application for SCRAMJET. (B) An analysis of sharp-edged nozzle exit designs for effective fuel injection into the flow stream in air-breathing engines: triangular-round and diamond-round nozzles. (C) Measurement technique improvements for the HU Low Speed Wind Tunnel (HU LSWT) including an automatic data acquisition system and a two component (drag-lift) balance system. In addition, a course in the field of aerodynamics was developed for the teaching and training of HU students.

  20. Advanced Methods for Aircraft Engine Thrust and Noise Benefits: Nozzle-Inlet Flow Analysis

    NASA Technical Reports Server (NTRS)

    Morgan, Morris H.; Gilinsky, Mikhail M.

    2001-01-01

    Three connected sub-projects were conducted under reported project. Partially, these sub-projects are directed to solving the problems conducted by the HU/FM&AL under two other NASA grants. The fundamental idea uniting these projects is to use untraditional 3D corrugated nozzle designs and additional methods for exhaust jet noise reduction without essential thrust lost and even with thrust augmentation. Such additional approaches are: (1) to add some solid, fluid, or gas mass at discrete locations to the main supersonic gas stream to minimize the negative influence of strong shock waves forming in propulsion systems; this mass addition may be accompanied by heat addition to the main stream as a result of the fuel combustion or by cooling of this stream as a result of the liquid mass evaporation and boiling; (2) to use porous or permeable nozzles and additional shells at the nozzle exit for preliminary cooling of exhaust hot jet and pressure compensation for non-design conditions (so-called continuous ejector with small mass flow rate; and (3) to propose and analyze new effective methods fuel injection into flow stream in air-breathing engines. Note that all these problems were formulated based on detailed descriptions of the main experimental facts observed at NASA Glenn Research Center. Basically, the HU/FM&AL Team has been involved in joint research with the purpose of finding theoretical explanations for experimental facts and the creation of the accurate numerical simulation technique and prediction theory for solutions for current problems in propulsion systems solved by NASA and Navy agencies. The research is focused on a wide regime of problems in the propulsion field as well as in experimental testing and theoretical and numerical simulation analysis for advanced aircraft and rocket engines. The F&AL Team uses analytical methods, numerical simulations, and possible experimental tests at the Hampton University campus. We will present some management activity

  1. Top-mounted inlet system feasibility for transonic-supersonic fighter aircraft. [V/STOL aircraft

    NASA Technical Reports Server (NTRS)

    Williams, T. L.; Hunt, B. L.; Smeltzer, D. B.; Nelms, W. P.

    1981-01-01

    The more salient findings are presented of recent top inlet performance evaluations aimed at assessing the feasibility of top-mounted inlet systems for transonic-supersonic fighter aircraft applications. Top inlet flow field and engine-inlet performance test data show the influence of key aircraft configuration variables-inlet longitudinal position, wing leading-edge extension planform area, canopy-dorsal integration, and variable incidence canards-on top inlet performance over the Mach range of 0.6 to 2.0. Top inlet performance data are compared with those or more conventional inlet/airframe integrations in an effort to assess the viability of top-mounted inlet systems relative to conventional inlet installations.

  2. Study of Bird Ingestions into Small Inlet Area, Aircraft Turbine Engines

    DTIC Science & Technology

    1989-12-01

    Statistical Analysis; ALF72 through the National Technical Bird Ingestion TFE731 Information Service, Springfield, Turbine Engine TPE331 Virginia 22161...Base C -- Statistical Methods Used J iii LIST OF ILLUSTRATIONS Figure Page 2.1 Engine Operations by Month and Engine Type 5 3.1 Engine Ingestions by...Ingestion Events 3.3 Summary Statistics for Ingested Bird Weights 10 4.1 Engine Ingestion Rate Estimates 18 4.2 Engine Ingestion Events and Rates by

  3. Study of Bird Ingestions into Small Inlet Area Aircraft Turbine Engines

    DTIC Science & Technology

    1990-12-01

    occurred on a civilian airplane resulting in the death of the copilot. Ingestion of birds into airplane engines is a safety problem for civil as well as... problem of engine damage resulting from bird ingestion is similar to that for windshield birdstrike, e.g., either design-consideration of the...well as the number of times it appears. The mode is a relevant measure of the bird ingestion problem . It represents the weight which will be

  4. Integral Engine Inlet Particle Separator. Volume 2. Design Guide

    DTIC Science & Technology

    1975-08-01

    herein will be used in the design of integral inlet particle separators for future Army aircraft gas turbine engines . Apprupriate technical personnel...OF INTEGRAL GAS TURBINE ENGINE SOLID PARTICLE INLET SEPARATORS, PHASE I, FEASIBILITY STUDY AND DESIGN, Pratt and Whitney Aircraft ; USAAVLABS Technical...USAAVLABS Technical Report 70-36, U.S. Army Aviation Materiel Laboratories, Fort Eustis, Virginia, August 1970 AD 876 584. 13. ENGINES , AIRCRAFT

  5. Wind tunnel tests of a zero length, slotted-lip engine air inlet for a fixed nacelle V/STOL aircraft

    NASA Technical Reports Server (NTRS)

    Woollett, R. R.; Beck, W. E., Jr.; Glasgow, E. R.

    1982-01-01

    Zero length, slotted lip inlet performance and associated fan blade stresses were determined during model tests using a 20 inch diameter fan simulator in the NASA-LeRC 9 by 15 foot low speed wind tunnel. The model configuration variables consisted of inlet contraction ratio, slot width, circumferential extent of slot fillers, and length of a constant area section between the inlet throat and fan face. The inlet performance was dependent on slot gap width and relatively independent of inlet throat/fan face spacer length and slot flow blockage created by 90 degree slot fillers. Optimum performance was obtained at a slot gap width of 0.36 inch. The zero length, slotted lip inlet satisfied all critical low speed inlet operating requirements for fixed horizontal nacelles subsonic V/STOL aircraft.

  6. 14 CFR 25.941 - Inlet, engine, and exhaust compatibility.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant General § 25.941 Inlet, engine, and exhaust compatibility. For airplanes using variable inlet or exhaust system geometry, or both... malfunctions) upon the aerodynamic control of the airplane may not result in any condition that would...

  7. 14 CFR 25.941 - Inlet, engine, and exhaust compatibility.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant General § 25.941 Inlet, engine, and exhaust compatibility. For airplanes using variable inlet or exhaust system geometry, or both... malfunctions) upon the aerodynamic control of the airplane may not result in any condition that would...

  8. 14 CFR 25.941 - Inlet, engine, and exhaust compatibility.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant General § 25.941 Inlet, engine, and exhaust compatibility. For airplanes using variable inlet or exhaust system geometry, or both... malfunctions) upon the aerodynamic control of the airplane may not result in any condition that would...

  9. 14 CFR 25.941 - Inlet, engine, and exhaust compatibility.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant General § 25.941 Inlet, engine, and exhaust compatibility. For airplanes using variable inlet or exhaust system geometry, or both... malfunctions) upon the aerodynamic control of the airplane may not result in any condition that would...

  10. 14 CFR 25.941 - Inlet, engine, and exhaust compatibility.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant General § 25.941 Inlet, engine, and exhaust compatibility. For airplanes using variable inlet or exhaust system geometry, or both... malfunctions) upon the aerodynamic control of the airplane may not result in any condition that would...

  11. Aircraft and Engine Development Testing

    DTIC Science & Technology

    1986-09-01

    Control in Flight * Integrated Inlet- engine * Power/weight Exceeds Unity F-lll * Advanced Engines * Augmented Turbofan * High Turbine Temperature...residence times). Also, fabrication of a small scale "hot" engine with rotating components such as compressors and turbines with cooled blades , is...capabil- ities are essential to meet the needs of current and projected aircraft and engine programs. The required free jet nozzles should be capable of

  12. Investigation of Flow Instabilities in the Inlet Ducts of DP-1C VTOL Aircraft

    NASA Technical Reports Server (NTRS)

    Lepicovsky, Jan

    2008-01-01

    An investigation of flow instabilities in the inlet ducts of a two-engine vertical takeoff and landing aircraft DP-1C is described in this report. Recent tests revealed that the engines stall during run ups while the aircraft is operating on the ground. These pop stalls occurred at relatively low power levels, sometimes as low as 60 percent of the engine full speed. Inability to run the engines up to the full speed level is attributed to in-ground effects associated with hot gas ingestion. Such pop stalls were never experienced when the aircraft was tested on a elevated grid platform, which ensured that the aircraft was operating in out-of-the-ground-effect conditions. Based on available information on problems experienced with other vertical takeoff and landing aircraft designs, it was assumed that the engine stalls were caused by partial ingestion of hot gases streaming forward from the main exit nozzle under the aircraft inlets, which are very close to the ground. It was also suggested that the nose wheel undercarriage, located between the inlets, may generate vortices or an unstable wake causing intense mixing of hot exit gases with incoming inlet flow, which would enhance the hot gas ingestion. After running a short three-day series of tests with fully instrumented engine inlets, it is now believed the most probable reason for engine pop stalls are random ingestions of a vortex generated between the two streams moving in opposite directions: outbound hot gas stream from the main nozzle close to the ground and inbound inlet flow above. Originally, the vortex is in a horizontal plane. However, at a certain velocity ratio of these two streams, the vortex attaches either to the ground or the aircraft surface at one end and the other end is swallowed by one of the aircraft inlets. Once the vortex enters the inlet duct, a puff of hot air can be sucked through the vortex core into the engine, which causes a serious inlet flow field distortion followed by an engine

  13. Vortex generator design for aircraft inlet distortion as a numerical optimization problem

    NASA Technical Reports Server (NTRS)

    Anderson, Bernhard H.; Levy, Ralph

    1991-01-01

    Aerodynamic compatibility of aircraft/inlet/engine systems is a difficult design problem for aircraft that must operate in many different flight regimes. Takeoff, subsonic cruise, supersonic cruise, transonic maneuvering, and high altitude loiter each place different constraints on inlet design. Vortex generators, small wing like sections mounted on the inside surfaces of the inlet duct, are used to control flow separation and engine face distortion. The design of vortex generator installations in an inlet is defined as a problem addressable by numerical optimization techniques. A performance parameter is suggested to account for both inlet distortion and total pressure loss at a series of design flight conditions. The resulting optimization problem is difficult since some of the design parameters take on integer values. If numerical procedures could be used to reduce multimillion dollar development test programs to a small set of verification tests, numerical optimization could have a significant impact on both cost and elapsed time to design new aircraft.

  14. Air-sampling inlet contamination by aircraft emissions on the NASA CV-990 aircraft

    NASA Technical Reports Server (NTRS)

    Condon, E. P.; Vedder, J. F.

    1984-01-01

    Results of an experimental investigation of the contamination of air sampling inlets by aircraft emissions from the NASA CV-990 research aircraft are presented. This four-engine jet aircraft is a NASA facility used for many different atmospheric and meteorological experiments, as well as for developing spacecraft instrumentation for remote measurements. Our investigations were performed to provide information on which to base the selection of sampling locations for a series of multi-instrument missions for measuring tropospheric trace gases. The major source of contamination is the exhaust from the jet engines, which generate many of the same gases that are of interest in atmospheric chemistry, as well as other gases that may interfere with sampling measurements. The engine exhaust contains these gases in mixing ratios many orders of magnitude greater than those that occur in the clean atmosphere which the missions seek to quantify. Pressurized samples of air were collected simultaneously from a scoop located forward of the engines to represent clean air and from other multiport scoops at various aft positions on the aircraft. The air samples were analyzed in the laboratory by gas chromatography for carbon monoxide, an abundant combustion by-product. Data are presented for various scoop locations under various flight conditions.

  15. Inlet Trade Study for a Low-Boom Aircraft Demonstrator

    NASA Technical Reports Server (NTRS)

    Heath, Christopher M.; Slater, John W.; Rallabhandi, Sriram K.

    2016-01-01

    Propulsion integration for low-boom supersonic aircraft requires careful inlet selection, placement, and tailoring to achieve acceptable propulsive and aerodynamic performance, without compromising vehicle sonic boom loudness levels. In this investigation, an inward-turning streamline-traced and axisymmetric spike inlet are designed and independently installed on a conceptual low-boom supersonic demonstrator aircraft. The airframe was pre-shaped to achieve a target ground under-track loudness of 76.4 PLdB at cruise using an adjoint-based design optimization process. Aircraft and inlet performance characteristics were obtained by solution of the steady-state Reynolds-averaged Navier-Stokes equations. Isolated cruise inlet performance including total pressure recovery and distortion were computed and compared against installed inlet performance metrics. Evaluation of vehicle near-field pressure signatures, along with under- and off-track propagated loudness levels is also reported. Results indicate the integrated axisymmetric spike design offers higher inlet pressure recovery, lower fan distortion, and reduced sonic boom. The vehicle with streamline-traced inlet exhibits lower external wave drag, which translates to a higher lift-to-drag ratio and increased range capability.

  16. Computational analysis of ramjet engine inlet interaction

    NASA Technical Reports Server (NTRS)

    Duncan, Beverly; Thomas, Scott

    1992-01-01

    A computational analysis of a ramjet engine at Mach 3.5 has been conducted and compared to results obtained experimentally. This study focuses on the behavior of the inlet both with and without combustor backpressure. Increased backpressure results in separation of the body side boundary layer and a resultant static pressure rise in the inlet throat region. The computational results compare well with the experimental data for static pressure distribution through the engine, inlet throat flow profiles, and mass capture. The computational analysis slightly underpredicts the thickness of the engine body surface boundary layer and the extent of the interaction caused by backpressure; however, the interaction is observed at approximately the same level of backpressure both experimentally and computationally. This study demonstrates the ability of two different Navier-Stokes codes, namely RPLUS and PARC, to calculate the flow features of this ramjet engine and to provide more detailed information on the process of inlet interaction and unstart.

  17. Aircraft Engine Emissions. [conference

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A conference on a aircraft engine emissions was held to present the results of recent and current work. Such diverse areas as components, controls, energy efficient engine designs, and noise and pollution reduction are discussed.

  18. Gas Turbine Engine Inlet Wall Design

    NASA Technical Reports Server (NTRS)

    Florea, Razvan Virgil (Inventor); Matalanis, Claude G. (Inventor); Stucky, Mark B. (Inventor)

    2016-01-01

    A gas turbine engine has an inlet duct formed to have a shape with a first ellipse in one half and a second ellipse in a second half. The second half has an upstream most end which is smaller than the first ellipse. The inlet duct has a surface defining the second ellipse which curves away from the first ellipse, such that the second ellipse is larger at an intermediate location. The second ellipse is even larger at a downstream end of the inlet duct leading into a fan.

  19. Gasdynamic Inlet Isolation in Rotating Detonation Engine

    DTIC Science & Technology

    2010-12-01

    ISOLATION IN ROTATING DETONATION ENGINE by Wei Han Eugene Lim December 2010 Thesis Co-Advisors: Jose O. Sinibaldi Christopher M. Brophy...COVERED Master’s Thesis 4. TITLE AND SUBTITLE Gasdynamic Inlet Isolation in Rotating Detonation Engine 6. AUTHOR(S) Wei Han Eugene Lim 5. FUNDING...DISTRIBUTION CODE 13. ABSTRACT (maximum 200 words) The Rotating Detonation Engine (RDE) concept represents the next-generation of detonation -based

  20. Calculation procedures for potential and viscous flow solutions for engine inlets

    NASA Technical Reports Server (NTRS)

    Albers, J. A.; Stockman, N. O.

    1973-01-01

    The method and basic elements of computer solutions for both potential flow and viscous flow calculations for engine inlets are described. The procedure is applicable to subsonic conventional (CTOL), short-haul (STOL), and vertical takeoff (VTOL) aircraft engine nacelles operating in a compressible viscous flow. The calculated results compare well with measured surface pressure distributions for a number of model inlets. The paper discusses the uses of the program in both the design and analysis of engine inlets, with several examples given for VTOL lift fans, acoustic splitters, and for STOL engine nacelles. Several test support applications are also given.

  1. Numerical and Test Investigation on an Aircraft Inlet Distortion

    NASA Astrophysics Data System (ADS)

    Zhang, Zhang; Hou, Anping; Chen, Yinxiu; Tuo, Wei; Xia, Aiguo

    2013-09-01

    Subscale wind tunnel test of an aircraft vehicle is performed at different Mach number, mass-flow and angle of attack. CFD model, corrected by test results, is also presented to predict inlet performance and total pressure distortion. The result shows total pressure recovery decreases and distortion level rises when Mach number increases from subsonic to supersonic speed, AOA is negative and mass-flow value is too large or too small. Compared linear interpolation based on test result of discrete probes, numerical simulation has advantages in showing inlet flow field predicting actual surface distortion level in AIP plane. Swirl distortion is induced by vortex near the fuselage and adjustable ramp and can strengthen total pressure distortion in AIP at negative AOA. And appropriate suction mass-flow coefficient (1.7% to 3%) is beneficial for inlet performance and total pressure distortion control.

  2. Energy efficient aircraft engines

    NASA Technical Reports Server (NTRS)

    Chamberlin, R.; Miller, B.

    1979-01-01

    The three engine programs that constitute the propulsion portion of NASA's Aircraft Energy Efficiency Program are described, their status indicated, and anticipated improvements in SFC discussed. The three engine programs are: (1) engine component improvement, directed at current engines, (2) energy efficient engine, directed at new turbofan engines, and (3) advanced turboprops, directed at technology for advanced turboprop-powered aircraft with cruise speeds to Mach 0.8. Unique propulsion system interactive ties to the airframe resulting from engine design features to reduce fuel consumption are discussed. Emphasis is placed on the advanced turboprop since it offers the largest potential fuel savings of the three propulsion programs and also has the strongest interactive ties to the airframe.

  3. Energy efficient aircraft engines

    NASA Technical Reports Server (NTRS)

    Chamberlin, R.; Miller, B.

    1979-01-01

    The three engine programs that constitute the propulsion portion of NASA's Aircraft Energy Efficiency Program are described, their status indicated, and anticipated improvements in SFC discussed. The three engine programs are (1) Engine Component Improvement--directed at current engines, (2) Energy Efficiency Engine directed at new turbofan engines, and (3) Advanced Turboprops--directed at technology for advanced turboprop--powered aircraft with cruise speeds to Mach 0.8. Unique propulsion system interactive ties to the airframe resulting from engine design features to reduce fuel consumption are discussed. Emphasis is placed on the advanced turboprop since it offers the largest potential fuel savings of the three propulsion programs and also has the strongest interactive ties to the airframe.

  4. Aircraft engines. II

    SciTech Connect

    Smith, M.G. Jr.

    1988-01-01

    An account is given of the design features and prospective performance gains of ultrahigh bypass subsonic propulsion configurations and various candidate supersonic commercial aircraft powerplants. The supersonic types, whose enhanced thermodynamic cycle efficiency is considered critical to the economic viability of a second-generation SST, are the variable-cycle engine, the variable stream control engine, the turbine-bypass engine, and the supersonic-throughflow fan. Also noted is the turboramjet concept, which will be applicable to hypersonic aircraft whose airframe structure materials can withstand the severe aerothermodynamic conditions of this flight regime.

  5. Aircraft engine pollution reduction

    NASA Technical Reports Server (NTRS)

    Rudey, R. A.

    1972-01-01

    The effect of engine operation on the types and levels of the major aircraft engine pollutants is described and the major factors governing the formation of these pollutants during the burning of hydrocarbon fuel are discussed. Methods which are being explored to reduce these pollutants are discussed and their application to several experimental research programs are pointed out. Results showing significant reductions in the levels of carbon monoxide, unburned hydrocarbons, and oxides of nitrogen obtained from experimental combustion research programs are presented and discussed to point out potential application to aircraft engines.

  6. An Inlet Distortion Assessment During Aircraft Departures at High Angle of Attack for an F/A-18A Aircraft

    NASA Technical Reports Server (NTRS)

    Steenken, William G.; Williams, John G.; Yuhas, Andrew J.; Walsh, Kevin R.

    1997-01-01

    The F404-GE-400-powered F/A-18A High Alpha Research Vehicle (HARV) was used to examine the quality of inlet airflow during departed flight maneuvers, that is, during flight outside the normal maneuvering envelope where control surfaces have little or no effectiveness. Six nose-left and six nose-right departures were initiated at Mach numbers between 0.3 and 0.4 at an altitude of 35 kft. The entry yaw rates were approximately 40 to 90 deg/sec. Engine surges were encountered during three of the nose-left and one of the nose-right departures. Time-variant inlet-total-pressure distortion levels at the engine face did not significantly exceed those at maximum angle-of-attack and sideslip maneuvers during controlled flight. Surges caused by inlet distortion levels resulted from a combination of high levels of inlet distortion and rapid changes in aircraft position. These rapid changes indicate a combination of engine support and gyroscopic loads being applied to the engine structure that impact the aerodynamic stability of the compressor through changes in the rotor-to-case clearances. This document presents the slides from an oral presentation.

  7. Aircraft engine mathematical model - linear system approach

    NASA Astrophysics Data System (ADS)

    Rotaru, Constantin; Roateşi, Simona; Cîrciu, Ionicǎ

    2016-06-01

    This paper examines a simplified mathematical model of the aircraft engine, based on the theory of linear and nonlinear systems. The dynamics of the engine was represented by a linear, time variant model, near a nominal operating point within a finite time interval. The linearized equations were expressed in a matrix form, suitable for the incorporation in the MAPLE program solver. The behavior of the engine was included in terms of variation of the rotational speed following a deflection of the throttle. The engine inlet parameters can cover a wide range of altitude and Mach numbers.

  8. DEVELOPMENT OF A SUPERSONIC TRANSPORT AIRCRAFT ENGINE - PHASE II-A.

    DTIC Science & Technology

    JET TRANSPORT PLANES, *SUPERSONIC AIRCRAFT ) (U) TURBOJET ENGINES , PERFORMANCE( ENGINEERING ), TURBOFAN ENGINES , AFTERBURNING, SPECIFICATIONS...COMPRESSORS, GEOMETRY, TURBOJET INLETS, COMBUSTION, TEST EQUIPMENT, TURBINE BLADES , HEAT TRANSFER, AIRFOILS , CASCADE STRUCTURES, EVAPOTRANSPIRATION, PLUG NOZZLES, ANECHOIC CHAMBERS, BEARINGS, SEALS, DESIGN, FATIGUE(MECHANICS)

  9. Aircraft studies of size-dependent aerosol sampling through inlets

    NASA Technical Reports Server (NTRS)

    Porter, J. N.; Clarke, A. D.; Ferry, G.; Pueschel, R. F.

    1992-01-01

    Representative measurement of aerosol from aircraft-aspirated systems requires special efforts in order to maintain near isokinetic sampling conditions, estimate aerosol losses in the sample system, and obtain a measurement of sufficient duration to be statistically significant for all sizes of interest. This last point is especially critical for aircraft measurements which typically require fast response times while sampling in clean remote regions. This paper presents size-resolved tests, intercomparisons, and analysis of aerosol inlet performance as determined by a custom laser optical particle counter. Measurements discussed here took place during the Global Backscatter Experiment (1988-1989) and the Central Pacific Atmospheric Chemistry Experiment (1988). System configurations are discussed including (1) nozzle design and performance, (2) system transmission efficiency, (3) nonadiabatic effects in the sample line and its effect on the sample-line relative humidity, and (4) the use and calibration of a virtual impactor.

  10. Optics in aircraft engines

    NASA Astrophysics Data System (ADS)

    Vachon, James; Malhotra, Subhash

    The authors describe optical IR&D (independent research and development) programs designed to demonstrate and evaluate optical technologies for incorporation into next-generation military and commercial aircraft engines. Using a comprehensive demonstration program to validate this technology in an on-engine environment, problems encountered can be resolved early and risk can be minimized. In addition to specific activities related to the optics demonstration on the fighter engine, there are other optical programs underway, including a solenoid control system, a light off detection system, and an optical communication link. Research is also underway in simplifying opto-electronics and exploiting multiplexing to further reduce cost and weight.

  11. Aircraft Engine Systems

    NASA Technical Reports Server (NTRS)

    Veres, Joseph

    2001-01-01

    This report outlines the detailed simulation of Aircraft Turbofan Engine. The objectives were to develop a detailed flow model of a full turbofan engine that runs on parallel workstation clusters overnight and to develop an integrated system of codes for combustor design and analysis to enable significant reduction in design time and cost. The model will initially simulate the 3-D flow in the primary flow path including the flow and chemistry in the combustor, and ultimately result in a multidisciplinary model of the engine. The overnight 3-D simulation capability of the primary flow path in a complete engine will enable significant reduction in the design and development time of gas turbine engines. In addition, the NPSS (Numerical Propulsion System Simulation) multidisciplinary integration and analysis are discussed.

  12. Fuel conservative aircraft engine technology

    NASA Technical Reports Server (NTRS)

    Nored, D. L.

    1978-01-01

    Technology developments for more fuel-efficiency subsonic transport aircraft are reported. Three major propulsion projects were considered: (1) engine component improvement - directed at current engines; (2) energy efficient engine - directed at new turbofan engines; and (3) advanced turboprops - directed at technology for advanced turboprop-powered aircraft. Each project is reviewed and some of the technologies and recent accomplishments are described.

  13. Inlet and airframe compatibility for a V/STOL fighter/attack aircraft with top-mounted inlets

    NASA Technical Reports Server (NTRS)

    Durston, D. A.; Smeltzer, D. B.

    1982-01-01

    Aerodynamic force and inlet-pressure data were obtained for 9.5% force and pressure models of a V/STOL fighter/attack aircraft configuration with top-mounted twin inlets. Data are presented from wind tunnel tests conducted at Mach numbers of 0.6, 0.9, and 1.2 at angles of attack up to 27-deg and angles of sideslip up to 12-deg. Trimmed aerodynamic characteristics and inlet performance were compared for three different leading-edge extension (LEX) configurations. The effects of wing leading- and trailing-edge flaps on the inlet were also determined. Maneuver performance was calculated from combined force and inlet-pressure data. The largest of the three LEX sizes tested gave the best airplane maneuver performance. Wing flap deflections improved inlet recovery at all Mach numbers.

  14. Inlet and airframe compatibility for a V/STOL fighter/attack aircraft with top-mounted inlets

    NASA Technical Reports Server (NTRS)

    Durston, D. A.; Smeltzer, D. B.

    1982-01-01

    Aerodynamic force and inlet pressure data are obtained for 9.5% force and pressure models of a V/STOL fighter/attack aircraft configuration with top mounted twin inlets. Data are presented from tests conducted in the Ames Unitary Wind Tunnels at Mach numbers of 0.6, 0.9, and 1.2 at angles of attack up to 27 deg. and angles of sideslip up to 12 deg. Trimmed aerodynamic characteristics and inlet performance are compared for three different leading edge extension (LEX) configurations. The effects of wing leading and trailing-edge flaps on the inlet are also determined. Maneuver perfromance is calculated form combined force and inlet pressure data. The largest of the three LEX sizes tested gives the best airplane maneuver performance. Wing flap deflections improved inlet recovery at all Mach numbers.

  15. Computer code for estimating installed performance of aircraft gas turbine engines. Volume 2: Users manual

    NASA Technical Reports Server (NTRS)

    Kowalski, E. J.

    1979-01-01

    A computerized method which utilizes the engine performance data and estimates the installed performance of aircraft gas turbine engines is presented. This installation includes: engine weight and dimensions, inlet and nozzle internal performance and drag, inlet and nacelle weight, and nacelle drag. A user oriented description of the program input requirements, program output, deck setup, and operating instructions is presented.

  16. Computer code for estimating installed performance of aircraft gas turbine engines. Volume 1: Final report

    NASA Technical Reports Server (NTRS)

    Kowalski, E. J.

    1979-01-01

    A computerized method which utilizes the engine performance data is described. The method estimates the installed performance of aircraft gas turbine engines. This installation includes: engine weight and dimensions, inlet and nozzle internal performance and drag, inlet and nacelle weight, and nacelle drag.

  17. Microelectrical Mechanical Systems Flow Control Used to Manage Engine Face Distortion in Compact Inlet Systems

    NASA Technical Reports Server (NTRS)

    Anderson, Bernhard H.; Miller, Daniel N.

    1999-01-01

    Turbofan engine-face flow distortion is one of the most troublesome and least understood problems for designers of modern engine inlet systems. One concern is that there are numerous sources of flow-field distortion that are ingested by the inlet or generated within the inlet duct itself. Among these are: (1) flow separation at the cowl lip during in-flight maneuvering, (2) flow separation on the compression surfaces due to shock-wave/boundary layer interactions, (3) spillage of the fuselage boundary layer into the inlet duct, (4) ingestion of aircraft vortices and wakes emanating from upstream disturbances, and (5) strong secondary flow gradients and flow separation induced by wall curvature within the inlet duct itself. Most developing aircraft (including the B70, F-111, F-14, Mig-25, Tornado, and Airbus A300) have experienced one or more of these types of problems, particularly at high Mach numbers and/or extreme maneuver conditions when flow distortion at the engine face exceeded the allowable limits of the engine.

  18. Experimental, water droplet impingement data on two-dimensional airfoils, axisymmetric inlet and Boeing 737-300 engine inlet

    NASA Technical Reports Server (NTRS)

    Papadakis, M.; Elangovan, E.; Freund, G. A., Jr.; Breer, M. D.

    1987-01-01

    An experimental method has been developed to determine the droplet impingement characteristics on two- and three-dimensional bodies. The experimental results provide the essential droplet impingement data required to validate particle trajectory codes, used in aircraft icing analyses and engine inlet particle separator analyses. A body whose water droplet impingement characteristics are required is covered at strategic locations by thin strips of moisture absorbing (blotter) paper, and then exposed to an air stream containing a dyed-water spray cloud. Water droplet impingement data are extracted from the dyed blotter strips, by measuring the optical reflectance of the dye deposit on the strips, using an automated reflectometer. Impingement efficiency data obtained for a NACA 65(2)015 airfoil section, a supercritical airfoil section, and Being 737-300 and axisymmetric inlet models are presented in this paper.

  19. Survey of inlet noise reduction concepts for gas turbine engines

    NASA Technical Reports Server (NTRS)

    Lansing, D. L.; Chestnutt, D.

    1976-01-01

    An overview is given of advanced concepts for the suppression of noise in the inlets of gas turbine engines. Inlet geometric and operating parameters are presented and design criteria for suppression methods are discussed. Noise suppression concepts are described, the directions of current research are reviewed. Problem areas requiring further work are indicated. Well established approaches to inlet noise reduction - namely, acoustic liners and high subsonic Mach number inlets which are the focus of considerable current research activity are considered along with the acoustic absorption and watet vapor injection.

  20. Computer code for estimating installed performance of aircraft gas turbine engines. Volume 3: Library of maps

    NASA Technical Reports Server (NTRS)

    Kowalski, E. J.

    1979-01-01

    A computerized method which utilizes the engine performance data and estimates the installed performance of aircraft gas turbine engines is presented. This installation includes: engine weight and dimensions, inlet and nozzle internal performance and drag, inlet and nacelle weight, and nacelle drag. The use of two data base files to represent the engine and the inlet/nozzle/aftbody performance characteristics is discussed. The existing library of performance characteristics for inlets and nozzle/aftbodies and an example of the 1000 series of engine data tables is presented.

  1. Should we attempt global (inlet engine airframe) control design?

    NASA Technical Reports Server (NTRS)

    Carlin, C. M.

    1980-01-01

    The feasibility of multivariable design of the entire airplane control system is briefly addressed. An intermediate step in that direction is to design a control for an inlet engine augmentor system by using multivariable techniques. The supersonic cruise large scale inlet research program is described which will provide an opportunity to develop, integrate, and wind tunnel test a control for a mixed compression inlet and variable cycle engine. The integrated propulsion airframe control program is also discussed which will introduce the problem of implementing MVC within a distributed processing avionics architecture, requiring real time decomposition of the global design into independent modules in response to hardware communication failures.

  2. Electro-impulse de-icing of a turbofan engine inlet

    NASA Technical Reports Server (NTRS)

    Zumwalt, G. W.

    1985-01-01

    The application of electromagnetic impulse deicing (EIDI) systems to turbofan engine inlets on business aircraft has been investigated experimentally. The tests were performed in the Icing Research Tunnel at NASA's Lewis Research Center. The deicing system testbed was a Falcon Fanjet 20 engine nacelle. The effectiveness of various deicing coil configurations and mount designs were compared, and design parameters were developed specifically for EIDI systems in turbofan engines. Flight tests were also carried out at altitudes in the range 3000-6000 ft corresponding to a temperature range of -3 to -8 C. It is shown that the ice particles removed from the engine inlet by the deicing system were small enough for the engine to ingest. Tentative design specifications are given with respect to the optimum coil configuration, and operating power of a EIDI production candidate.

  3. Alloy design for aircraft engines

    NASA Astrophysics Data System (ADS)

    Pollock, Tresa M.

    2016-08-01

    Metallic materials are fundamental to advanced aircraft engines. While perceived as mature, emerging computational, experimental and processing innovations are expanding the scope for discovery and implementation of new metallic materials for future generations of advanced propulsion systems.

  4. A Finite Element Computation of the Electromagnetic Fields within an Engine Inlet Model.

    DTIC Science & Technology

    1982-12-01

    Configuration," Proceedings of the 1980 Radar Camouflage Symposium , sponsored by the USAF Avionics Laboratory and Martin Marietta Corp. (November 1980 ). 4...Skolnik, Merrill I. Introduction to Radar Systems (Second Edition). New York: McGraw-Hill Book Company, 1980 . 2. Moll, John W. and Rolf G. Seecamp...engine inlet provides a significant contribution to the overall radar cross section of a modern aircraft. Before this contribu- ticn can be effectively

  5. Variable geometry inlet design for scram jet engine

    NASA Technical Reports Server (NTRS)

    Guinan, Daniel P. (Inventor); Drake, Alan (Inventor); Andreadis, Dean (Inventor); Beckel, Stephen A. (Inventor)

    2005-01-01

    The present invention relates to an improved variable geometry inlet for a scram jet engine having at least one combustor module. The variable geometry inlet comprises each combustor module having two sidewalls. Each of the sidewalls has a central portion with a thickness and a tapered profile forward of the central portion. The tapered profile terminates in a sharp leading edge. The variable geometry inlet further comprises each module having a lower wall and a movable cowl flap positioned forward of the lower wall. The movable cowl flap has a leading edge and the leading edges of the sidewalls intersect the leading edge of the cowl flap.

  6. Summary of investigations of engine response to distorted inlet conditions

    NASA Technical Reports Server (NTRS)

    Biesiadny, T. J.; Braithwaite, W. M.; Soeder, R. H.; Abdelwahab, M.

    1986-01-01

    A survey is presented of experimental and analytical experience of the NASA Lewis Research Center in engine response to inlet temperature and pressure distortions. This includes a description of the hardware and techniques employed, and a summary of the highlights of experimental investigations and analytical modeling. Distortion devices successfully simulated inlet distortion, and knowledge was gained about compression system response to different types of distortion. A list of NASA research references is included.

  7. Force and pressure characteristics for a series of nose inlets at Mach numbers from 1.59 to 1.99 V : analysis and comparison on basis of ram-jet aircraft range and operational characteristics

    NASA Technical Reports Server (NTRS)

    Howard, E; Luidens, R W; Allen, J L

    1951-01-01

    Performance of four experimentally investigated axially symmetric spike-type nose inlets is compared on basis of ram-jet-engine aircraft range and operational problems. At design conditions, calculated peak engine efficiencies varied 25 percent from the highest value which indicates importance of inlet design. Calculations for a typical supersonic aircraft indicate possible increase in range if engine is flown at moderate angle of attack and result in engine lift utilized. For engines with fixed exhaust nozzle, propulsive thrust increases with increasing heat addition in subcritical flow region in spite of increasing additive drag. For the perforated inlet there is a range of increasing total-temperature ratios in subcritical flow region that does not yield an increase in propulsive thrust. Effects of inlet characteristics on speed stability of a typical aircraft for three types of fuel control is discussed.

  8. Performance of a Supersonic Over-Wing Inlet with Application to a Low-Sonic-Boom Aircraft

    NASA Technical Reports Server (NTRS)

    Trefny, Charles J.; Hirt, Stefanie M.; Anderson, Bernhard H.; Fink, Lawrence E.; Magee, Todd E.

    2014-01-01

    Development of commercial supersonic aircraft has been hindered by many related factors including fuel-efficiency, economics, and sonic-boom signatures that have prevented over-land flight. Materials, propulsion, and flight control technologies have developed to the point where, if over-land flight were made possible, a commercial supersonic transport could be economically viable. Computational fluid dynamics, and modern optimization techniques enable designers to reduce the boom signature of candidate aircraft configurations to acceptable levels. However, propulsion systems must be carefully integrated with these low-boom configurations in order that the signatures remain acceptable. One technique to minimize the downward propagation of waves is to mount the propulsion systems above the wing, such that the wing provides shielding from shock waves generated by the inlet and nacelle. This topmounted approach introduces a number of issues with inlet design and performance especially with the highly-swept wing configurations common to low-boom designs. A 1.79%-scale aircraft model was built and tested at the NASA Glenn Research Center's 8-by 6-Foot Supersonic Wind Tunnel (8x6 SWT) to validate the configuration's sonic boom signature. In order to evaluate performance of the top-mounted inlets, the starboard flow-through nacelle on the aerodynamic model was replaced by a 2.3%-scale operational inlet model. This integrated configuration was tested at the 8x6 SWT from Mach 0.25 to 1.8 over a wide range of angles-of-attack and yaw. The inlet was also tested in an isolated configuration over a smaller range of angles-of-attack and yaw. A number of boundary-layer bleed configurations were investigated and found to provide a substantial positive impact on pressure recovery and distortion. Installed inlet performance in terms of mass capture, pressure recovery, and distortion over the Mach number range at the design angle-of-attack of 4-degrees is presented herein and compared

  9. Inlet Distortion for an F/A-18A Aircraft During Steady Aerodynamic Conditions up to 60 deg Angle of Attack

    NASA Technical Reports Server (NTRS)

    Walsh, Kevin R.; Yuhas, Andrew J.; Williams, John G.; Steenken, William G.

    1997-01-01

    The effects of high-angle-of-attack flight on aircraft inlet aerodynamic characteristics were investigated at NASA Dryden Flight Research Center, Edwards, California, as part of NASA's High Alpha Technology Program. The highly instrumented F/A-18A High Alpha Research Vehicle was used for this research. A newly designed inlet total-pressure rake was installed in front of the starboard F404-GE-400 engine to measure inlet recovery and distortion characteristics. One objective was to determine inlet total-pressure characteristics at steady high-angle-of-attack conditions. Other objectives include assessing whether significant differences exist in inlet distortion between rapid angle-of-attack maneuvers and corresponding steady aerodynamic conditions, assessing inlet characteristics during aircraft departures, providing data for developing and verifying computational fluid dynamic codes, and calculating engine airflow using five methods. This paper addresses the first objective by summarizing results of 79 flight maneuvers at steady aerodynamic conditions, ranging from -10 deg to 60 deg angle of attack and from -8 deg to 11 deg angle of sideslip at Mach 0.3 and 0.4. These data and the associated database have been rigorously validated to establish a foundation for understanding inlet characteristics at high angle of attack.

  10. HINCOF-1: a Code for Hail Ingestion in Engine Inlets

    NASA Technical Reports Server (NTRS)

    Gopalaswamy, N.; Murthy, S. N. B.

    1995-01-01

    One of the major concerns during hail ingestion into an engine is the resulting amount and space- and time-wise distribution of hail at the engine face for a given geometry of inlet and set of atmospheric and flight conditions. The appearance of hail in the capture streamtube is invariably random in space and time, with respect to size and momentum. During the motion of a hailstone through an inlet, a hailstone undergoes several processes, namely impact with other hailstones and material surfaces of the inlet and spinner, rolling and rebound following impact; heat and mass transfer; phase change; and shattering, the latter three due to friction and impact. Taking all of these factors into account, a numerical code, designated HINCOF-I, has been developed for determining the motion hailstones from the atmosphere, through an inlet, and up to the engine face. The numerical procedure is based on the Monte-Carlo method. The report presents a description of the code, along with several illustrative cases. The code can be utilized to relate the spinner geometry - conical or, more effective, elliptical - to the possible diversion of hail at the engine face into the bypass stream. The code is also useful for assessing the influence of various hail characteristics on the ingestion and distribution of hailstones over the engine face.

  11. QCGAT aircraft/engine design for reduced noise and emissions

    NASA Technical Reports Server (NTRS)

    Lanson, L.; Terrill, K. M.

    1980-01-01

    The high bypass ratio QCGAT engine played an important role in shaping the aircraft design. The aircraft which evolved is a sleek, advanced design, six-place aircraft with 3538 kg (7,800 lb) maximum gross weight. It offers a 2778 kilometer (1500 nautical mile) range with cruise speed of 0.5 Mach number and will take-off and land on the vast majority of general aviation airfields. Advanced features include broad application of composite materials and a supercritical wing design with winglets. Full-span fowler flaps were introduced to improve landing capability. Engines are fuselage-mounted with inlets over the wing to provide shielding of fan noise by the wing surfaces. The design objectives, noise, and emission considerations, engine cycle and engine description are discussed as well as specific design features.

  12. Microphone Boom for Aircraft-Engine Monitoring

    NASA Technical Reports Server (NTRS)

    Cohn, R.; Economu, M.; Albrecht, W.

    1986-01-01

    Microphone for measuring aircraft engine noise mounted on lengthwise boom supported away from fuselage and engine. This configuration minimizes boundary-layer effects and pressure doubling that is present if microphone were mounted in aircraft fuselage.

  13. Fretting in aircraft turbine engines

    NASA Technical Reports Server (NTRS)

    Johnson, R. L.; Bill, R. C.

    1974-01-01

    The problem of fretting in aircraft turbine engines is discussed. Critical fretting can occur on fan, compressor, and turbine blade mountings, as well as on splines, rolling element bearing races, and secondary sealing elements of face type seals. Structural fatigue failures have been shown to occur at fretted areas on component parts. Methods used by designers to reduce the effects of fretting are given.

  14. Sea level static calibration of a compact multimission aircraft propulsion simulator with inlet flow distortion

    NASA Technical Reports Server (NTRS)

    Won, Mark J.

    1990-01-01

    Wind tunnel tests of propulsion-integrated aircraft models have identified inlet flow distortion as a major source of compressor airflow measurement error in turbine-powered propulsion simulators. Consequently, two Compact Multimission Aircraft Propulsion Simulator (CMAPS) units were statically tested at sea level ambient conditions to establish simulator operating performance characteristics and to calibrate the compressor airflow against an accurate bellmouth flowmeter in the presence of inlet flow distortions. The distortions were generated using various-shaped wire mesh screens placed upstream of the compressor. CMAPS operating maps and performance envelopes were obtained for inlet total pressure distortions (ratio of the difference between the maximum and minimum total pressures to the average total pressure) up to 35 percent, and were compared to baseline simulator operating characteristics for a uniform inlet. Deviations from CMAPS baseline performance were attributed to the coupled variation of both compressor inlet-flow distortion and Reynolds number index throughout the simulator operating envelope for each screen configuration. Four independent methods were used to determine CMAPS compressor airflow; direct compressor inlet and discharge measurements, an entering/exiting flow-balance relationships, and a correlation between the mixer pressure and the corrected compressor airflow. Of the four methods, the last yielded the least scatter in the compressor flow coefficient, approximately + or - 3 percent over the range of flow distortions.

  15. Physics of Acoustic Radiation from Jet Engine Inlets

    NASA Technical Reports Server (NTRS)

    Tam, Christopher K. W.; Parrish, Sarah A.; Envia, Edmane; Chien, Eugene W.

    2012-01-01

    Numerical simulations of acoustic radiation from a jet engine inlet are performed using advanced computational aeroacoustics (CAA) algorithms and high-quality numerical boundary treatments. As a model of modern commercial jet engine inlets, the inlet geometry of the NASA Source Diagnostic Test (SDT) is used. Fan noise consists of tones and broadband sound. This investigation considers the radiation of tones associated with upstream propagating duct modes. The primary objective is to identify the dominant physical processes that determine the directivity of the radiated sound. Two such processes have been identified. They are acoustic diffraction and refraction. Diffraction is the natural tendency for an acoustic wave to follow a curved solid surface as it propagates. Refraction is the turning of the direction of propagation of sound waves by mean flow gradients. Parametric studies on the changes in the directivity of radiated sound due to variations in forward flight Mach number and duct mode frequency, azimuthal mode number, and radial mode number are carried out. It is found there is a significant difference in directivity for the radiation of the same duct mode from an engine inlet when operating in static condition and in forward flight. It will be shown that the large change in directivity is the result of the combined effects of diffraction and refraction.

  16. Engine Performance and Knock Rating of Fuels for High-output Aircraft Engines

    NASA Technical Reports Server (NTRS)

    Rothbrock, A M; Biermann, Arnold E

    1938-01-01

    Data are presented to show the effects of inlet-air pressure, inlet-air temperature, and compression ratio on the maximum permissible performance obtained on a single-cylinder test engine with aircraft-engine fuels varying from a fuel of 87 octane number to one 100 octane number plus 1 ml of tetraethyl lead per gallon. The data were obtained on a 5-inch by 5.75-inch liquid-cooled engine operating at 2,500 r.p.m. The compression ratio was varied from 6.50 to 8.75. The inlet-air temperature was varied from 120 to 280 F. and the inlet-air pressure from 30 inches of mercury absolute to the highest permissible. The limiting factors for the increase in compression ratio and in inlet-air pressure was the occurrence of either audible or incipient knock. The data are correlated to show that, for any one fuel,there is a definite relationship between the limiting conditions of inlet-air temperature and density at any compression ratio. This relationship is dependent on the combustion-gas temperature and density relationship that causes knock. The report presents a suggested method of rating aircraft-engine fuels based on this relationship. It is concluded that aircraft-engine fuels cannot be satisfactorily rated by any single factor, such as octane number, highest useful compression ratio, or allowable boost pressure. The fuels should be rated by a curve that expresses the limitations of the fuel over a variety of engine conditions.

  17. Aircraft Engine Sump Fire Mitigation

    NASA Technical Reports Server (NTRS)

    Rosenlieb, J. W.

    1973-01-01

    An investigation was performed of the conditions in which fires can result and be controlled within the bearing sump simulating that of a gas turbine engine; Esso 4040 Turbo Oil, Mobil Jet 2, and Monsanto MCS-2931 lubricants were used. Control variables include the oil inlet temperature, bearing temperature, oil inlet and scavenge rates, hot air inlet temperature and flow rate, and internal sump baffling. In addition to attempting spontaneous combustion, an electric spark and a rub (friction) mechanism were employed to ignite fires. Spontaneous combustion was not obtained; however, fires were readily ignited with the electric spark while using each of the three test lubricants. Fires were also ignited using the rub mechanism with the only test lubricant evaluated, Esso 4040. Major parameters controlling ignitions were: Sump configuration; Bearing and oil temperatures, hot air temperature and flow and bearing speed. Rubbing between stationary parts and rotating parts (eg. labyrinth seal and mating rub strip) is a very potent fire source suggesting that observed accidental fires in gas turbine sumps may well arise from this cause.

  18. Aircraft Engine Sump Fire Mitigation, Phase 2

    NASA Technical Reports Server (NTRS)

    Rosenlieb, J. W.

    1978-01-01

    The effect of changes in the input parameters (air leakage flow rate and temperature and lubricating oil inlet flow rate and temperature) over a specified range on the flammability conditions within an aircraft engine bearing sump was investigated. An analytical study was performed to determine the effect of various parameters on the generation rate of oil vapor from oil droplets in a hot air stream flowing in a cylindrical tube. The ignition of the vapor-air mixture by an ignition source was considered. The experimental investigation demonstrated that fires would be ignited by a spark ignitor over the full range of air and oil flow rates and air temperatures evaluated. However, no fires could be ignited when the oil inlet temperature was maintained below 41.7 K (290 F). The severity of the fires ignited were found to be directly proportional to the hot air flow rate. Reasonably good correlation was found between the mixture temperature in the sump at the ignitor location and the flammability limits as defined by flammability theory; thus a fairly reliable experimental method of determining flammable conditions within a sump was demonstrated. The computerized mathematical model shows that oil droplet size and air temperature have the greatest influence on the generation rate of oil vapor.

  19. Adaptive Optimization of Aircraft Engine Performance Using Neural Networks

    NASA Technical Reports Server (NTRS)

    Simon, Donald L.; Long, Theresa W.

    1995-01-01

    Preliminary results are presented on the development of an adaptive neural network based control algorithm to enhance aircraft engine performance. This work builds upon a previous National Aeronautics and Space Administration (NASA) effort known as Performance Seeking Control (PSC). PSC is an adaptive control algorithm which contains a model of the aircraft's propulsion system which is updated on-line to match the operation of the aircraft's actual propulsion system. Information from the on-line model is used to adapt the control system during flight to allow optimal operation of the aircraft's propulsion system (inlet, engine, and nozzle) to improve aircraft engine performance without compromising reliability or operability. Performance Seeking Control has been shown to yield reductions in fuel flow, increases in thrust, and reductions in engine fan turbine inlet temperature. The neural network based adaptive control, like PSC, will contain a model of the propulsion system which will be used to calculate optimal control commands on-line. Hopes are that it will be able to provide some additional benefits above and beyond those of PSC. The PSC algorithm is computationally intensive, it is valid only at near steady-state flight conditions, and it has no way to adapt or learn on-line. These issues are being addressed in the development of the optimal neural controller. Specialized neural network processing hardware is being developed to run the software, the algorithm will be valid at steady-state and transient conditions, and will take advantage of the on-line learning capability of neural networks. Future plans include testing the neural network software and hardware prototype against an aircraft engine simulation. In this paper, the proposed neural network software and hardware is described and preliminary neural network training results are presented.

  20. 19 CFR 10.183 - Duty-free entry of civil aircraft, aircraft engines, ground flight simulators, parts, components...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Duty-free entry of civil aircraft, aircraft engines, ground flight simulators, parts, components, and... aircraft, aircraft engines, and ground flight simulators, including their parts, components, and... United States Coast Guard, aircraft, aircraft engines, and ground flight simulators, including...

  1. 19 CFR 10.183 - Duty-free entry of civil aircraft, aircraft engines, ground flight simulators, parts, components...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Duty-free entry of civil aircraft, aircraft engines, ground flight simulators, parts, components, and... aircraft, aircraft engines, and ground flight simulators, including their parts, components, and... United States Coast Guard, aircraft, aircraft engines, and ground flight simulators, including...

  2. 19 CFR 10.183 - Duty-free entry of civil aircraft, aircraft engines, ground flight simulators, parts, components...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Duty-free entry of civil aircraft, aircraft engines, ground flight simulators, parts, components, and... aircraft, aircraft engines, and ground flight simulators, including their parts, components, and... United States Coast Guard, aircraft, aircraft engines, and ground flight simulators, including...

  3. 19 CFR 10.183 - Duty-free entry of civil aircraft, aircraft engines, ground flight simulators, parts, components...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Duty-free entry of civil aircraft, aircraft engines, ground flight simulators, parts, components, and... aircraft, aircraft engines, and ground flight simulators, including their parts, components, and... United States Coast Guard, aircraft, aircraft engines, and ground flight simulators, including...

  4. 19 CFR 10.183 - Duty-free entry of civil aircraft, aircraft engines, ground flight simulators, parts, components...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Duty-free entry of civil aircraft, aircraft engines, ground flight simulators, parts, components, and... aircraft, aircraft engines, and ground flight simulators, including their parts, components, and... United States Coast Guard, aircraft, aircraft engines, and ground flight simulators, including...

  5. 75 FR 32315 - Airworthiness Directives; Various Aircraft Equipped With Rotax Aircraft Engines 912 A Series Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-08

    ..., 912 F, and 912 S series engines. Versions of the 912 F series and 912 S series engines are type... not have an engine type certificate; instead, the engine is part of the aircraft type design. You may... Equipped With Rotax Aircraft Engines 912 A Series Engines AGENCY: Federal Aviation Administration...

  6. FORTRAN program to generate engine inlet flow contour maps and distortion parameters

    NASA Technical Reports Server (NTRS)

    Dicus, J. H.

    1974-01-01

    A computer program is presented and described that generates jet engine inlet flow contour maps and inlet flow distortion parameters. The program input consists of an array of measurements describing the flow conditions at the engine inlet. User-defined distortion parameters may be calculated.

  7. Highly integrated digital electronic control: Digital flight control, aircraft model identification, and adaptive engine control

    NASA Technical Reports Server (NTRS)

    Baer-Riedhart, Jennifer L.; Landy, Robert J.

    1987-01-01

    The highly integrated digital electronic control (HIDEC) program at NASA Ames Research Center, Dryden Flight Research Facility is a multiphase flight research program to quantify the benefits of promising integrated control systems. McDonnell Aircraft Company is the prime contractor, with United Technologies Pratt and Whitney Aircraft, and Lear Siegler Incorporated as major subcontractors. The NASA F-15A testbed aircraft was modified by the HIDEC program by installing a digital electronic flight control system (DEFCS) and replacing the standard F100 (Arab 3) engines with F100 engine model derivative (EMD) engines equipped with digital electronic engine controls (DEEC), and integrating the DEEC's and DEFCS. The modified aircraft provides the capability for testing many integrated control modes involving the flight controls, engine controls, and inlet controls. This paper focuses on the first two phases of the HIDEC program, which are the digital flight control system/aircraft model identification (DEFCS/AMI) phase and the adaptive engine control system (ADECS) phase.

  8. Prediction of sound radiated from different practical jet engine inlets

    NASA Technical Reports Server (NTRS)

    Zinn, B. T.; Meyer, W. L.

    1980-01-01

    Existing computer codes for calculating the far field radiation patterns surrounding various practical jet engine inlet configurations under different excitation conditions were upgraded. The computer codes were refined and expanded so that they are now more efficient computationally by a factor of about three and they are now capable of producing accurate results up to nondimensional wave numbers of twenty. Computer programs were also developed to help generate accurate geometrical representations of the inlets to be investigated. This data is required as input for the computer programs which calculate the sound fields. This new geometry generating computer program considerably reduces the time required to generate the input data which was one of the most time consuming steps in the process. The results of sample runs using the NASA-Lewis QCSEE inlet are presented and comparison of run times and accuracy are made between the old and upgraded computer codes. The overall accuracy of the computations is determined by comparison of the results of the computations with simple source solutions.

  9. Experimental Water Droplet Impingement Data on Airfoils, Simulated Ice Shapes, an Engine Inlet and a Finite Wing

    NASA Technical Reports Server (NTRS)

    Papadakis, M.; Breer, M.; Craig, N.; Liu, X.

    1994-01-01

    An experimental method has been developed to determine the water droplet impingement characteristics on two- and three-dimensional aircraft surfaces. The experimental water droplet impingement data are used to validate particle trajectory analysis codes that are used in aircraft icing analyses and engine inlet particle separator analyses. The aircraft surface is covered with thin strips of blotter paper in areas of interest. The surface is then exposed to an airstream that contains a dyed-water spray cloud. The water droplet impingement data are extracted from the dyed blotter paper strips by measuring the optical reflectance of each strip with an automated reflectometer. Experimental impingement efficiency data represented for a NLF (1)-0414 airfoil, a swept MS (1)-0317 airfoil, a Boeing 737-300 engine inlet model, two simulated ice shapes and a swept NACA 0012 wingtip. Analytical impingement efficiency data are also presented for the NLF (1)-0414 airfoil and the Boeing 737-300 engine inlet model.

  10. Lightweight diesel aircraft engines for general aviation

    NASA Technical Reports Server (NTRS)

    Berenyi, S. G.; Brouwers, A. P.

    1980-01-01

    A methodical design study was conducted to arrive at new diesel engine configurations and applicable advanced technologies. Two engines are discussed and the description of each engine includes concept drawings. A performance analysis, stress and weight prediction, and a cost study were also conducted. This information was then applied to two airplane concepts, a six-place twin and a four-place single engine aircraft. The aircraft study consisted of installation drawings, computer generated performance data, aircraft operating costs and drawings of the resulting airplanes. The performance data shows a vast improvement over current gasoline-powered aircraft. At the completion of this basic study, the program was expanded to evaluate a third engine configuration. This third engine incorporates the best features of the original two, and its design is currently in progress. Preliminary information on this engine is presented.

  11. Active Combustion Control for Aircraft Gas Turbine Engines

    NASA Technical Reports Server (NTRS)

    DeLaat, John C.; Breisacher, Kevin J.; Saus, Joseph R.; Paxson, Daniel E.

    2000-01-01

    Lean-burning combustors are susceptible to combustion instabilities. Additionally, due to non-uniformities in the fuel-air mixing and in the combustion process, there typically exist hot areas in the combustor exit plane. These hot areas limit the operating temperature at the turbine inlet and thus constrain performance and efficiency. Finally, it is necessary to optimize the fuel-air ratio and flame temperature throughout the combustor to minimize the production of pollutants. In recent years, there has been considerable activity addressing Active Combustion Control. NASA Glenn Research Center's Active Combustion Control Technology effort aims to demonstrate active control in a realistic environment relevant to aircraft engines. Analysis and experiments are tied to aircraft gas turbine combustors. Considerable progress has been shown in demonstrating technologies for Combustion Instability Control, Pattern Factor Control, and Emissions Minimizing Control. Future plans are to advance the maturity of active combustion control technology to eventual demonstration in an engine environment.

  12. Smart actuation of inlet guide vanes for small turbine engine

    NASA Astrophysics Data System (ADS)

    Rusovici, Razvan; Kwok Choon, Stephen T.; Sepri, Paavo; Feys, Joshuo

    2011-04-01

    Unmanned Aerial Vehicles (UAVs) have gained popularity over the past few years to become an indispensable part of aerial missions that include reconnaissance, surveillance, and communication [1]. As a result, advancements in small jet-engine performance are needed to increase the performance (range, payload and efficiency) of the UAV. These jet engines designed especially for UAV's are characterized by thrust force on the order of 100N and due to their size and weight limitations, may lack advanced flow control devices such as IGV [2]. The goal of the current study was to present a conceptual design of an IGV smart-material based actuation mechanism that would be simple, compact and lightweight. The compressor section of an engine increases the pressure and conditions the flow before the air enters the combustion chamber [3]. The airflow entering the compressor is often turbulent due to the high angle of incidence between engine inlet and free-stream velocity, or existing atmospheric turbulence. Actuated IGV are used to help control the relative angle of incidence of the flow that enters the engine compressor, thereby preventing flow separation, compressor stall and thus extending the compressor's operating envelope [4]. Turbine jet- engines which employ variable IGV were developed by Rolls Royce (Trent DR-900) and General Electric (J79).

  13. A survey of inlet/engine distortion compatibility

    NASA Technical Reports Server (NTRS)

    Bowditch, D. N.; Coltrin, R. E.

    1983-01-01

    The history of distortion analysis is traced back to its origin in parallel compressor theory which was initially proposed in the late fifties. The development of this theory is reviewed up to its inclusion in the complex computer codes of today. It is found to be a very useful tool to guide development but not quantitative enough to predict compatibility. Dynamic or instantaneous distortion methodology is also reviewed from its origins in the sixties, to its current application in the eighties. Many of the requirements for interpreting instantaneous distortion are considered and illustrated. Statistical methods for predicting the peak distortion are described, and their limitations and advantages discussed. Finally, some Reynolds number and scaling considerations for inlet testing are considered. It is concluded that the deterministic instantaneous distortion methodology combined with distortion testing of engines with screens will remain the primary method of predicting compatibility for the near future. However, parallel compressor analysis and statistical peak distortion prediction will be important tools employed during the development of inlet/engine compatibility.

  14. Research on hypersonic aircraft using pre-cooled turbojet engines

    NASA Astrophysics Data System (ADS)

    Taguchi, Hideyuki; Kobayashi, Hiroaki; Kojima, Takayuki; Ueno, Atsushi; Imamura, Shunsuke; Hongoh, Motoyuki; Harada, Kenya

    2012-04-01

    Systems analysis of a Mach 5 class hypersonic aircraft is performed. The aircraft can fly across the Pacific Ocean in 2 h. A multidisciplinary optimization program for aerodynamics, structure, propulsion, and trajectory is used in the analysis. The result of each element model is improved using higher accuracy analysis tools. The aerodynamic performance of the hypersonic aircraft is examined through hypersonic wind tunnel tests. A thermal management system based on the data of the wind tunnel tests is proposed. A pre-cooled turbojet engine is adopted as the propulsion system for the hypersonic aircraft. The engine can be operated continuously from take-off to Mach 5. This engine uses a pre-cooling cycle using cryogenic liquid hydrogen. The high temperature inlet air of hypersonic flight would be cooled by the same liquid hydrogen used as fuel. The engine is tested under sea level static conditions. The engine is installed on a flight test vehicle. Both liquid hydrogen fuel and gaseous hydrogen fuel are supplied to the engine from a tank and cylinders installed within the vehicle. The designed operation of major components of the engine is confirmed. A large amount of liquid hydrogen is supplied to the pre-cooler in order to make its performance sufficient for Mach 5 flight. Thus, fuel rich combustion is adopted at the afterburner. The experiments are carried out under the conditions that the engine is mounted upon an experimental airframe with both set up either horizontally or vertically. As a result, the operating procedure of the pre-cooled turbojet engine is demonstrated.

  15. Technology for reducing aircraft engine pollution

    NASA Technical Reports Server (NTRS)

    Rudey, R. A.; Kempke, E. E., Jr.

    1975-01-01

    Programs have been initiated by NASA to develop and demonstrate advanced technology for reducing aircraft gas turbine and piston engine pollutant emissions. These programs encompass engines currently in use for a wide variety of aircraft from widebody-jets to general aviation. Emission goals for these programs are consistent with the established EPA standards. Full-scale engine demonstrations of the most promising pollutant reduction techniques are planned within the next three years. Preliminary tests of advanced technology gas turbine engine combustors indicate that significant reductions in all major pollutant emissions should be attainable in present generation aircraft engines without adverse effects on fuel consumption. Fundamental-type programs are yielding results which indicate that future generation gas turbine aircraft engines may be able to utilize extremely low pollutant emission combustion systems.

  16. Wind-Tunnel Investigation of Air Inlet and Outlet Openings for Aircraft, Special Report

    NASA Technical Reports Server (NTRS)

    Rogallo, Francis M.; Gauvain, William E.

    1938-01-01

    An investigation was made in the NACA 5-foot vertical wind tunnel of a large variety of duct inlets and outlets to obtain information relative to their design for the cooling or the ventilation systems on aircraft. Most of the tests were of openings in a flat plate but, in order to determine the best locations and the effects of interference, a few tests were made of openings in an airfoil. The best inlet location for a system not including a blower was found to be at the forward stagnation point; for one including a blower, the best location was found to be in the region of lowest total head, probably in the boundary layer near the trailing edge. Design recommendations are given, and it is shown that correct design demands a knowledge of the external flow and of the internal requirements in addition to that obtained from the results of the wind tunnel tests.

  17. Coupled Analysis of an Inlet and Fan for a Quiet Supersonic Aircraft

    NASA Technical Reports Server (NTRS)

    Chima, Rodrick V.; Conners, Timothy R.; Wayman, Thomas R.

    2009-01-01

    A computational analysis of a Gulfstream isentropic external compression supersonic inlet coupled to a Rolls-Royce fan was completed. The inlet was designed for a small, low sonic boom supersonic vehicle with a design cruise condition of M = 1.6 at 45,000 feet. The inlet design included an annular bypass duct that routed flow subsonically around an engine-mounted gearbox and diverted flow with high shock losses away from the fan tip. Two Reynolds-averaged Navier-Stokes codes were used for the analysis: an axisymmetric code called AVCS for the inlet and a 3-D code called SWIFT for the fan. The codes were coupled at a mixing plane boundary using a separate code for data exchange. The codes were used to determine the performance of the inlet/fan system at the design point and to predict the performance and operability of the system over the flight profile. At the design point the core inlet had a recovery of 96 percent, and the fan operated near its peak efficiency and pressure ratio. A large hub radial distortion generated in the inlet was not eliminated by the fan and could pose a challenge for subsequent booster stages. The system operated stably at all points along the flight profile. Reduced stall margin was seen at low altitude and Mach number where flow separated on the interior lips of the cowl and bypass ducts. The coupled analysis gave consistent solutions at all points on the flight profile that would be difficult or impossible to predict by analysis of isolated components.

  18. Improvements in teaching aircraft engine design

    SciTech Connect

    Mattingly, J.D.; Heiser, W.H. Tennessee, University, Tullahoma )

    1992-07-01

    Aircraft gas turbine analysis and design pedagogy can be enriched through the incorporation improved preliminary engine thrust and fuel consumption models, novel computer programs for both aircraft system analysis and turbomechanical design, and a new perspective for engine-cycle analysis. Four computer programs have been developed for preliminary engine design; two of these automate aircraft system analysis, while another designs multistage axial-flow compressors and the last designs multistage axial-flow turbines. Student confusion with 'design-point' and 'off-design' concepts is by these means reduced. 6 refs.

  19. Supersonic fan engines for military aircraft

    NASA Technical Reports Server (NTRS)

    Franciscus, L. C.

    1983-01-01

    Engine performance and mission studies were performed for turbofan engines with supersonic through-flow fans. A Mach 2.4 CTOL aircraft was used in the study. Two missions were considered: a long range penetrator mission and a long range intercept mission. The supersonic fan engine is compared with an augmented mixed flow turbofan in terms of mission radius for a fixed takeoff gross weight of 75,000 lbm. The mission radius of aircraft powered by supersonic fan engines could be 15 percent longer than aircraft powered with conventional turbofan engines at moderate thrust to gross weight ratios. The climb and acceleration performance of the supersonic fan engines is better than that of the conventional turbofan engines.

  20. On the inlet vortex system. [preventing jet engine damage caused by debris pick-up

    NASA Technical Reports Server (NTRS)

    Bissinger, N. C.; Braun, G. W.

    1974-01-01

    The flow field of a jet engine with an inlet vortex, which can pick up heavy debris from the ground and damage the engine, was simulated in a small water tunnel by means of the hydrogen bubble technique. It was found that the known engine inlet vortex is accompained by a vortex system, consisting of two inlet vortices (the ground based and the trailing one), secondary vortices, and ground vortices. Simulation of the ground effect by an inlet image proved that the inlet vortex feeds on free stream vorticity and can exist without the presence of a ground boundary layer. The structural form of the inlet vortex system was explained by a simple potential flow model, which showed the number, location, and the importance of the stagnation points. A retractable horizontal screen or an up-tilt of the engine is suggested as countermeasure against debris ingestion.

  1. Integrated engine generator for aircraft secondary power

    NASA Technical Reports Server (NTRS)

    Secunde, R. R.

    1972-01-01

    An integrated engine-generator for aircraft secondary power generation is described. The concept consists of an electric generator located inside a turbojet or turbofan engine and both concentric with and driven by one of the main engine shafts. The electric power conversion equipment and generator controls are located in the aircraft. When properly rated, the generator serves as an engine starter as well as a source of electric power. This configuration reduces or eliminates the need for an external gear box on the engine and permits reduction in the nacelle diameter.

  2. Cycle Counting Methods of the Aircraft Engine

    ERIC Educational Resources Information Center

    Fedorchenko, Dmitrii G.; Novikov, Dmitrii K.

    2016-01-01

    The concept of condition-based gas turbine-powered aircraft operation is realized all over the world, which implementation requires knowledge of the end-of-life information related to components of aircraft engines in service. This research proposes an algorithm for estimating the equivalent cyclical running hours. This article provides analysis…

  3. Top-mounted inlet performance for a V/STOL fighter/attack aircraft configuration

    NASA Technical Reports Server (NTRS)

    Smeltzer, Donald B.

    1987-01-01

    Inlet flow-field and compressor-face performance data were obtained for a 0.095-scale model of vertical/short take-off landing (V/STOL) fighter/attack aircraft configuration with twin top-mounted inlets. Tests were conducted at Mach numbers from 0.6 to 2.0 and angles of attack and sideslip up to 27 deg. and 12 deg., respectively. Reynolds number was held constant at 9.8 x 10 to the 6th power per meter. The effects of inlet location, wing leading-edge extension (LEX) planform area, canopy-dorsal integration, variable incidence canards, and wing leading- and trailing-edge flap deflections were determined. The results show that at Mach numbers up to 0.9, distortion is relatively low (20% or less) at all angles of attack and sideslip. However, at Mach numbers of 1.2 and above, operation may be restricted because of either high distortion or low pressure recovery (80% or less), or both. These difficulties may be overcome with alterations to the LEX/canopy/body juncture.

  4. Interference Effects of Fuselage-Stored Missiles on Inlet Duct Model of an Interceptor-Type Aircraft at Mach Numbers 1.5 to 1.9

    NASA Technical Reports Server (NTRS)

    Piercy, T. G.; Davis, O. H.

    1957-01-01

    The effect of missile armament on the performance of an interceptor-type aircraft model has been determined at Mach numbers 1.5, 1.7, and 1.9 and at angles of attack to 19 deg. With this configuration missiles were carried in a bay located on the bottom of the aircraft fuselage and mounted to a rotatable missile door. Rotation of the door then brought the missiles into the external or firing position. The aircraft model was characterized by triangular-shaped normal-shock inlets located at the wing roots. Relatively short and curved subsonic diffusers fed simulated twin side-by-side turbojet engines. Inasmuch as the missile bay extended considerably ahead of the inlet station, rotation of the missile door created considerable disturbance of the flow entering the inlets. In comparison with the internal missile arrangement, the external missile configurations increased the model lift, drag, and pitching moment. While the diffuser-exit flow distortion and static-pressure fluctuations were not greatly affected, diffuser total-pressure recovery was reduced as much as 0.058 at Mach number 1.9 for one missile configuration. The most detrimental effect of missile-door rotation occurred at the transient door positions, or with the door halfwzy between the missiles-in and -out conditions. At this door position the flow into the inlets was highly asymmetrical. Although the performance of both left and right ducts was generally reduced, the inlet duct on the cavity side of the missile door was most severely penalized, becoming unstable recovery losses and increases in flow distortion. The installation of fuselage fences along the missile bay was only partially effective in reducing these losses.

  5. Review of Aircraft Engine Fan Noise Reduction

    NASA Technical Reports Server (NTRS)

    VanZante, Dale

    2008-01-01

    Aircraft turbofan engines incorporate multiple technologies to enhance performance and durability while reducing noise emissions. Both careful aerodynamic design of the fan and proper installation of the fan into the system are requirements for achieving the performance and acoustic objectives. The design and installation characteristics of high performance aircraft engine fans will be discussed along with some lessons learned that may be applicable to spaceflight fan applications.

  6. Ice Protection of Turbojet Engines by Inertia Separation of Water III : Annular Submerged Inlets

    NASA Technical Reports Server (NTRS)

    Von Glahn, Uwe

    1948-01-01

    Aerodynamic and icing studies were conducted on a one-half-scale model of an annular submerged inlet for use with axial-flow turbojet engines. Pressure recoveries, screen radial-velocity profiles, circumferential mass-flow variations, and icing characteristics were determined at the compressor inlet. In order to be effective in maintaining water-free induction air, the inlet gap must be extremely small and ram-pressure recoveries consequently are low, the highest achieved being 65 percent at inlet-velocity ratio of 0.86. All inlets exhibited considerable screen icing. Severe mass-flow shifts occurred at angles of attack.

  7. Aircraft

    DTIC Science & Technology

    2002-01-01

    Company, Washington, DC Boeing Commercial Aircraft Division, Seattle, WA and Long Beach, CA Boeing Military Aircraft and Missile Division, St. Louis, MO and... aircraft ; military fixed-wing aircraft ; rotorcraft (helicopters and tiltrotor aircraft ); and aircraft jet engines. Two companies dominate the commercial... aircraft business, Boeing and Airbus. Four companies dominate the military fixed-wing market, Boeing, Lockheed Martin, BAE Systems, and European

  8. Dynamics of a supersonic inlet-engine combination subjected to disturbances in fuel flow and inlet overboard bypass airflow

    NASA Technical Reports Server (NTRS)

    Wallhagen, R. E.; Paulovich, F. J.; Geyser, L. C.

    1972-01-01

    An axisymmetric mixed-compression supersonic inlet and a single-spool turbojet engine were dynamically tested at Mach 2.5. The propulsion system was subjected to sweep-frequency sinusoidal disturbances of either inlet overboard bypass airflow. The disturbances were at a logarithmic sweep rate of 1 decade per minute. Dynamic responses were taken of signals throughout the propulsion system. Selected signals were reduced relative to the prime propulsion system parameters. The experimental data are presented in Bode plots. Most of the plots are for a frequency range of 1.0 to 50 hertz.

  9. Lightweight diesel aircraft engines for general aviation

    NASA Technical Reports Server (NTRS)

    Berenyi, S. G.

    1983-01-01

    Two different engines were studied. The advantages of a diesel to general aviation were reduced to fuel consumption, reduced operating costs, and reduced fire and explosion hazard. There were no ignition mixture control or inlet icing problems. There are fewer controls and no electrical interference problems.

  10. Engine selection for transport and combat aircraft

    NASA Technical Reports Server (NTRS)

    Dugan, J. F., Jr.

    1972-01-01

    The procedures that are used to select engines for transport and combat aircraft are discussed. In general, the problem is to select the engine parameters including engine size in such a way that all constraints are satisfied and airplane performance is maximized. This is done for four different classes of aircraft: (1) a long haul conventional takeoff and landing (CTOL) transport, (2) a short haul vertical takeoff and landing (VTOL) transport, (3) a long range supersonic transport (SST), and (4) a fighter aircraft. For the commercial airplanes the critical constraints have to do with noise while for the fighter, maneuverability requirements define the engine. Generally, the resultant airplane performance (range or payload) is far less than that achievable without these constraints and would suffer more if nonoptimum engines were selected.

  11. 77 FR 44429 - Airworthiness Directives; Various Aircraft Equipped With Rotax Aircraft Engines 912 A Series Engine

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-30

    ... this AD: Aeromot AMT 300 Turbo Super Ximango and Stemme S10 VT have a Rotax 914 engine installed, not a... certificate holder Aircraft model Engine model Aeromot-Ind stria AMT-200 912 A2 Mec nico- Metal rgica...

  12. 77 FR 39623 - Airworthiness Standards: Aircraft Engines; Technical Amendment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-05

    ... Part 33 [Amendment No. 33-33] Airworthiness Standards: Aircraft Engines; Technical Amendment AGENCY... amendment clarifies aircraft engine vibration test requirements in the airworthiness standards. The clarification is in response to inquiries from applicants requesting FAA engine type certifications...

  13. Mechanical characteristics of stability-bleed valves for a supersonic inlet. [for the YF-12 aircraft

    NASA Technical Reports Server (NTRS)

    Neiner, G. H.; Dustin, M. O.; Cole, G. L.

    1977-01-01

    Mechanical characteristics of a set of direct-operated relief valves used in a throat-bypass stability-bleed system designed for the YF-12 aircraft inlet are described. A comparison of data taken before and after the windtunnel tests (at room temperature) showed that both the effective spring rate and the piston friction had decreased during the wind tunnel tests. In neither the effective spring rate nor the piston friction was the magnitude of change great enough to cause significant impairment of overall system effectiveness. No major valve mechanical problems were encountered in any of the tests. During high temperature bench tests, piston frictional drag increased. The friction returned to its initial room temperature value when the stability-bleed valve was disassembled and reassembled. The problem might be solved by using a different material for the piston sleeve bearing and the piston rings.

  14. Investigation of Aerodynamic and Icing Characteristics of Water-Inertia-Separation Inlets for Turbojet Engines

    NASA Technical Reports Server (NTRS)

    VonGlahn, Uwe; Blatz, R. E.

    1950-01-01

    The results of an investigation of several internal water-inertia-separation inlets consisting of a main duct and an alternate duct designed to prevent automatically the entrance of large quantities of water into a turbojet engine in icing conditions are presented. Total-pressure losses and icing characteristics for a direct-ram inlet and the inertia-separation inlets are compared at similar aerodynamic and simulated icing conditions. Complete ice protection for inlet guide vanes could not be achieved with the inertia-separation inlets investigated. Approximately 8 percent of the volume of water entering the nacelles remained. In the air passing into the compressor inlet. Heavy alternate-duct-elbow ice formations caused by secondary inertia separation resulted in rapid total-pressure losses and decreases in mass flow. The duration in an icing condition for an inertia-separation- inlet, without local surface heating, was increased approximately four times above that for a direct-ram inlet with a compressor-inlet screen. For normal nonicing operation, the inertia-separation- inlet total-pressure losses were comparable to a direct-ram installation. The pressure losses and the circumferential uniformity of the mass flow in all the inlets were relatively independent of angle of attack. Use of an inertia-separation inlet would in most cases require a larger diameter nacelle than a direct-ram inlet in order to obtain an alternate duct sufficiently large to pass the required engine air flow at duct Mach numbers below 1.0 at the minimum area.

  15. 75 FR 70098 - Airworthiness Directives; Various Aircraft Equipped With Rotax Aircraft Engines 912 A Series Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-17

    ... crankcase surface to remove any oil. (ii) Warm up the engine to a minimum oil temperature of 50 degrees C (120 degrees F). Information about warming up the engine can be found in the applicable line... Aircraft Engines 912 A series engine with a crankcase assembly S/N up to and including S/N...

  16. Testing of the NASA Hypersonics Project Combined Cycle Engine Large Scale Inlet Mode Transition Experiment (CCE LlMX)

    NASA Technical Reports Server (NTRS)

    Saunders, J. D.; Stueber, T. J.; Thomas, S. R.; Suder, K. L.; Weir, L. J.; Sanders, B. W.

    2012-01-01

    Status on an effort to develop Turbine Based Combined Cycle (TBCC) propulsion is described. This propulsion technology can enable reliable and reusable space launch systems. TBCC propulsion offers improved performance and safety over rocket propulsion. The potential to realize aircraft-like operations and reduced maintenance are additional benefits. Among most the critical TBCC enabling technologies are: 1) mode transition from turbine to scramjet propulsion, 2) high Mach turbine engines and 3) TBCC integration. To address these TBCC challenges, the effort is centered on a propulsion mode transition experiment and includes analytical research. The test program, the Combined-Cycle Engine Large Scale Inlet Mode Transition Experiment (CCE LIMX), was conceived to integrate TBCC propulsion with proposed hypersonic vehicles. The goals address: (1) dual inlet operability and performance, (2) mode-transition sequences enabling a switch between turbine and scramjet flow paths, and (3) turbine engine transients during transition. Four test phases are planned from which a database can be used to both validate design and analysis codes and characterize operability and integration issues for TBCC propulsion. In this paper we discuss the research objectives, features of the CCE hardware and test plans, and status of the parametric inlet characterization testing which began in 2011. This effort is sponsored by the NASA Fundamental Aeronautics Hypersonics project

  17. A 727 airplane center duct inlet low speed performance confirmation model test for refanned JT8D engines, phase 2

    NASA Technical Reports Server (NTRS)

    Kaldschmidt, G.; Syltebo, B. E.; Ting, C. T.

    1973-01-01

    The results from testing of a 0.3 scale model center duct inlet (S duct) for the Pratt and Whitney Aircraft JT8D-100 engines are presented. The objective of this test was to demonstrate that the required airflow of the JT8D-100 engine (480 lb/sec as compared to 334 lb/sec for JT8D-15) can be achieved with minimum modifications to the existing 727 airplane structure at acceptable levels of total pressure recovery and distortion. Steady-state pressure recovery, steady-state pressure distortion, and dynamic pressure measurements were taken at the engine face station. Surface static pressure measurements were taken along the duct. Test results indicated that the required airflow was achieved with acceptable pressure recovery (comparable to the current 727-200 S duct). Inlet inflow angle variation within the 727 airplane operating regime (minus 5 to 5 degrees) had no effect on the inlet performance. Pressure distortion at static and forward speed at takeoff airflow conditions are within P and WA limits for the Phase II duct when equipped with vortex generators. Static crosswind operation between 10 knots and 25 knots appears feasible at full takeoff power.

  18. Effects of fan inlet temperature disturbances on the stability of a turbofan engine

    NASA Technical Reports Server (NTRS)

    Abdelwahab, M.

    1981-01-01

    The effects of steady-state and time-dependent fan inlet total temperature disturbances on the stability of a TF30-P-3 turbofan engine were determined. Disturbances were induced by a gaseous-hydrogen-fueled burner system installed upstream of the fan inlet. Data were obtained at a fan inlet Reynolds number index of 0.50 and at a low-pressure-rotor corrected speed of 90 percent of military speed. All tests were conducted with a 90 deg extent of the fan inlet circumference exposed to above-average temperatures.

  19. Sonic inlet noise attenuation and performance with a J-85 turbojet engine as a noise source

    NASA Technical Reports Server (NTRS)

    Groth, H. W.

    1974-01-01

    A static test program was conducted to investigate aerodynamic and acoustic performance of a sonic inlet used as a noise suppressor. A translating centerbody type inlet with radial vanes was tested ahead of a J85-GE-13 turbojet engine. The inlet when fully choked, maintained high recovery with low distortions while dramatically reducing noise emanating from the compressor. Recoveries of 98.1% at simulated takeoff and 95% at approach were attained with associated sound attenuation of 40 db and 38 db respectively. Inlet lip shape was found to have significant effects on noise attenuation at these static conditions.

  20. Dropping aircraft-deployable GPS stations on Scar Inlet and Pine Island Glacier.

    NASA Astrophysics Data System (ADS)

    Hilmar Gudmundsson, G.; Jones, David

    2013-04-01

    There remains areas of scientific interest that heavy crevassing makes difficult or impossible to reach by ground via overland treks or an aircraft landing. We have developed an alternative strategy for instrumenting these regions: a sensor probe that can be dropped from an aircraft, partially bury itself in the snow whilst keeping its antennas protruding high above the surface to ensure a long operating life. Our probe has a 2.5m, 10kg missile-shaped design and can be deployed through a standard sonar-buoy launch tube. In order to achieve a consistent impact depth in different snow densities the case is fitted with fold-out fins one metre from the nose cone. This ensures a large step-change in impact surface area when the device is embedded to the correct depth. A small disk-gap-band parachute improves the angle of impact while damping any probe oscillations. We are now able to achieve near-vertical impact angles and a consistent snow penetration depth of one metre. The sensor is cheap to make (approximately £1000) and has a minimal environmental impact. This year we have used a large network of these sensors to instrument previously inaccessible parts of Scar Inlet and Pine Island Glacier.

  1. Shock Position Control for Mode Transition in a Turbine Based Combined Cycle Engine Inlet Model

    NASA Technical Reports Server (NTRS)

    Csank, Jeffrey T.; Stueber, Thomas J.

    2013-01-01

    A dual flow-path inlet for a turbine based combined cycle (TBCC) propulsion system is to be tested in order to evaluate methodologies for performing a controlled inlet mode transition. Prior to experimental testing, simulation models are used to test, debug, and validate potential control algorithms which are designed to maintain shock position during inlet disturbances. One simulation package being used for testing is the High Mach Transient Engine Cycle Code simulation, known as HiTECC. This paper discusses the development of a mode transition schedule for the HiTECC simulation that is analogous to the development of inlet performance maps. Inlet performance maps, derived through experimental means, describe the performance and operability of the inlet as the splitter closes, switching power production from the turbine engine to the Dual Mode Scram Jet. With knowledge of the operability and performance tradeoffs, a closed loop system can be designed to optimize the performance of the inlet. This paper demonstrates the design of the closed loop control system and benefit with the implementation of a Proportional-Integral controller, an H-Infinity based controller, and a disturbance observer based controller; all of which avoid inlet unstart during a mode transition with a simulated disturbance that would lead to inlet unstart without closed loop control.

  2. 14 CFR 21.6 - Manufacture of new aircraft, aircraft engines, and propellers.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Manufacture of new aircraft, aircraft..., DEPARTMENT OF TRANSPORTATION AIRCRAFT CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS General § 21.6 Manufacture of new aircraft, aircraft engines, and propellers. (a) Except as specified in paragraphs (b)...

  3. 14 CFR 21.6 - Manufacture of new aircraft, aircraft engines, and propellers.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Manufacture of new aircraft, aircraft..., DEPARTMENT OF TRANSPORTATION AIRCRAFT CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS General § 21.6 Manufacture of new aircraft, aircraft engines, and propellers. (a) Except as specified in paragraphs (b)...

  4. 14 CFR 21.6 - Manufacture of new aircraft, aircraft engines, and propellers.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Manufacture of new aircraft, aircraft..., DEPARTMENT OF TRANSPORTATION AIRCRAFT CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS General § 21.6 Manufacture of new aircraft, aircraft engines, and propellers. (a) Except as specified in paragraphs (b)...

  5. Method of vibration isolating an aircraft engine

    NASA Technical Reports Server (NTRS)

    Bender, Stanley I. (Inventor); Butler, Lawrence (Inventor); Dawes, Peter W. (Inventor)

    1991-01-01

    A method for coupling an engine to a support frame for mounting to a fuselage of an aircraft using a three point vibration isolating mounting system in which the load reactive forces at each mounting point are statically and dynamically determined. A first vibration isolating mount pivotably couples a first end of an elongated support beam to a stator portion of an engine with the pivoting action of the vibration mount being oriented such that it is pivotable about a line parallel to a center line of the engine. An aft end of the supporting frame is coupled to the engine through an additional pair of vibration isolating mounts with the mounts being oriented such that they are pivotable about a circumference of the engine. The aft mounts are symmetrically spaced to each side of the supporting frame by 45 degrees. The relative orientation between the front mount and the pair of rear mounts is such that only the rear mounts provide load reactive forces parallel to the engine center line, in support of the engine to the aircraft against thrust forces. The forward mount is oriented so as to provide only radial forces to the engine and some lifting forces to maintain the engine in position adjacent a fuselage. Since each mount is connected to provide specific forces to support the engine, forces required of each mount are statically and dynamically determinable.

  6. 78 FR 54385 - Airworthiness Directives; Various Aircraft Equipped With Rotax Aircraft Engines 912 A Series Engine

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-04

    ... condition exists and is likely to exist or develop on other products of the same type design. FAA's.... Table 1 of Paragraph (c)--Affected Airplanes Type certificate holder Aircraft model Engine model Aeromot-Ind stria AMT-200 912 A2 Mec nico- Metal rgica Ltda. Diamond Aircraft Industries...... HK 36 R...

  7. Aircraft Engineering Conference 1934 - Full Scale Tunnel

    NASA Technical Reports Server (NTRS)

    1934-01-01

    Gathered together in the only facility big enough to hold them, attendees at Langleys 1934 aircraft Engineering Conference pose in the Full Scale Wind Tunnel underneath a Boeing P-26A Peashooter. Present, among other notables, were Orville Wright, Charles Lindbergh, and Howard Hughes.

  8. Electronic materials testing in commercial aircraft engines

    NASA Astrophysics Data System (ADS)

    Brand, Dieter

    A device for the electronic testing of materials used in commercial aircraft engines is described. The instrument can be used for ferromagnetic, ferrimagnetic, and nonferromagnetic metallic materials, and it functions either optically or acoustically. The design of the device is described and technical data are given. The device operates under the principle of controlled self-inductivity. Its mode of operation is described.

  9. Flow Forming of Aircraft Engine Components

    DTIC Science & Technology

    2006-05-01

    Canada 1000 Marie Victorin, Longueuil Québec J4G 1A1 CANADA jean.Savoie@pwc.ca ABSTRACT Aircraft engine components are often an assembly of...1000 Marie Victorin, Longueuil Québec J4G 1A1 CANADA 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES

  10. Aircraft Piston Engine Exhaust Emission Symposium

    NASA Technical Reports Server (NTRS)

    1976-01-01

    A 2-day symposium on the reduction of exhaust emissions from aircraft piston engines was held on September 14 and 15, 1976, at the Lewis Research Center in Cleveland, Ohio. Papers were presented by both government organizations and the general aviation industry on the status of government contracts, emission measurement problems, data reduction procedures, flight testing, and emission reduction techniques.

  11. De-Icing of Aircraft Turbine Engine Inlets

    DTIC Science & Technology

    1988-06-01

    this report. Technical Rope"t Documentation Pal* 2.Roag e Govemmassf Acesesion Me. 3 . Rkeump....,g C0141011 M.. DOT/FAA/C T-87/37 I________ 4.~~~S Tifs...5 2- 3 Combination of Hot Air, Oil and Electrical Ice Protection in L Turbojet Installation...19 ICE ACCRETION AND DR-ICING EVALUATION 3 -1 Four-Point Bend Loading ......................................... 20 3 -2 Rheological Model for Dynamic

  12. Engineering and Technical Configuration Aspects of HIAPER, the new NSF/NCAR Research Aircraft

    NASA Astrophysics Data System (ADS)

    Friesen, R.; Laursen, K.

    2002-12-01

    The High-performance Instrumented Airborne Platform for Environmental Research, or HIAPER, is the new research aircraft presently being developed at the National Center for Atmospheric Research (NCAR) to serve the environmental research needs of the National Science Foundation (NSF) for the next several decades. The basic aircraft -- a Gulfstream V (G-V) business jet -- has been completed and will shortly undergo extensive modification to prepare it for future deployments in support of a variety of geosciences research missions. This presentation will focus on the many design and engineering considerations that have been made and are yet to come in converting a "green" business jet into a versatile research aircraft to serve the environmental research community. The project teams composed of engineers and scientists from NCAR and the scientific community at large are faced with trade offs involving costs of modifications, airframe structural integrity, aircraft performance (e.g. weight, drag), cabin environment, locations of inlet and sampling ports and FAA certification requirements. Many of the specific engineering specifications and modifications that have been made to date will be presented by way of engineering drawings, graphical depictions and actual photographs of the aircraft structure. Additionally, projected performance data of the modified-for-research aircraft will be presented along with some of the analyses performed to arrive at critical decisions (e.g. CFD airflow analysis). Finally, some of the details of the aircraft "infrastructure" such as signal and power wiring, generic cabin layout and data acquisition will be discussed.

  13. 14 CFR 21.128 - Tests: aircraft engines.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Tests: aircraft engines. 21.128 Section 21... engines. (a) Each person manufacturing aircraft engines under a type certificate only shall subject each engine (except rocket engines for which the manufacturer must establish a sampling technique) to...

  14. 14 CFR 21.128 - Tests: aircraft engines.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Tests: aircraft engines. 21.128 Section 21... engines. (a) Each person manufacturing aircraft engines under a type certificate only shall subject each engine (except rocket engines for which the manufacturer must establish a sampling technique) to...

  15. Advanced aircraft engine materials trends

    NASA Technical Reports Server (NTRS)

    Dreshfield, R. L.; Gray, H. R.; Levine, S. R.; Signorelli, R.

    1981-01-01

    Recent activities of the Lewis Research Center are reviewed which are directed toward developing materials for rotating hot section components for aircraft gas turbines. Turbine blade materials activities are directed at increasing metal temperatures approximately 100 C compared to current directionally solidified alloys by use of oxide dispersion strengthening or tungsten alloy wire reinforcement of nickel or iron base superalloys. The application of thermal barrier coatings offers a promise of increasing gas temperatures an additional 100 C with current cooling technology. For turbine disk alloys, activities are directed toward reducing the cost of turbine disks by 50 percent through near net shape fabrication of prealloyed powders as well as towards improved performance. In addition, advanced alloy concepts and fabrication methods for dual alloy disks are being studied as having potential for improving the life of future high performance disks and reducing the amount of strategic materials required in these components.

  16. Improving the performance of a compression ignition engine by directing flow of inlet air

    NASA Technical Reports Server (NTRS)

    Kemper, Carlton

    1946-01-01

    The object of this report is to present the results of tests performed by the National Advisory Committee for Aeronautics to determine the effect on engine performance of directing the flow of the inlet air to a 5-inch by 7-inch cylinder, solid injection, compression ignition engine, After a few preliminary tests, comparative runs were made at a speed of 1500 r.p.m. with and without directed air flow. It was found that directing the flow of the inlet air toward the fuel injection valve gave steadier engine operation, and an appreciable increase in power, and decreased fuel consumption. The results indicate the possibility of improving the performance of a given type of combustion chamber without changing its shape and with no change in valve timing. They would also seem to prove that directional turbulence, set up before the inlet valve of a four-stroke cycle engine, continues in the engine cylinder throughout the compression stroke.

  17. Diesel engine catalytic combustor system. [aircraft engines

    NASA Technical Reports Server (NTRS)

    Ream, L. W. (Inventor)

    1984-01-01

    A low compression turbocharged diesel engine is provided in which the turbocharger can be operated independently of the engine to power auxiliary equipment. Fuel and air are burned in a catalytic combustor to drive the turbine wheel of turbine section which is initially caused to rotate by starter motor. By opening a flapper value, compressed air from the blower section is directed to catalytic combustor when it is heated and expanded, serving to drive the turbine wheel and also to heat the catalytic element. To start, engine valve is closed, combustion is terminated in catalytic combustor, and the valve is then opened to utilize air from the blower for the air driven motor. When the engine starts, the constituents in its exhaust gas react in the catalytic element and the heat generated provides additional energy for the turbine section.

  18. Effects of inlet distortion on a static pressure probe mounted on the engine hub in an F-15 airplane

    NASA Technical Reports Server (NTRS)

    Hughes, D. L.; Myers, L. P.; Mackall, K. G.

    1985-01-01

    An inlet static pressure (PS2) probe was mounted on the hub of an F100 engine in an F-15 airplane. Flight test results showed that for low distortion conditions, the ratio of engine-face total pressure to static pressure agreed well with previous altitude facility data. Off-schedule operation of the inlet third ramp angle caused increased distortion of the inlet airflow during steady-state flight conditions. Data are shown for inlet third ramp excursions leading to engine stall. The relationships of inlet face total to static pressure ratio as a function of several distortion descriptors are also described.

  19. Analysis of Porous Media as Inlet Concept for Rotating Detonation Engines

    NASA Astrophysics Data System (ADS)

    Grogan, Kevin; Ihme, Matthias; Department of Mechanical Engineering Team

    2016-11-01

    Rotating detonation engines combust reactive gas mixtures with a high-speed, annularly-propagating detonation wave, which provides many advantages including a stagnation pressure gain and a compact, lightweight design. However, the optimal design of the inlet to the combustion chamber inlet is a moot topic since improper design can significantly reduce detonability and increase pressure losses. The highly diffusive properties of porous media could make it an ideal material to prevent the flashback of the detonation wave and therefore, allow the inlet gas to be premixed. Motivated by this potential, this work employs simulation to evaluate the application of porous media to the inlet of a rotating detonation engine as a novel means to stabilize a detonation wave while reducing the pressure losses incurred by non-ideal mixing strategies. Department of the Air Force.

  20. Performance and surge limits of a TF30-P-3 turbofan engine/axisymmetric mixed-compression inlet propulsion system at Mach 2.5

    NASA Technical Reports Server (NTRS)

    Wasserbauer, J. F.; Neumann, H. E.; Shaw, R. J.

    1985-01-01

    Steady-state performance and inlet-engine compatibility were investigated with a low-bleed inlet. The inlet had minimum internal contraction, consistent with high total pressure recovery and low cowl drag. The inlet-engine combination displayed good performance with only about 2% of inlet performance bleed. The inlet-engine combination had 5.58 deg angle-of-attack capability with 6% bleed.

  1. Prediction of sound radiation from different practical jet engine inlets

    NASA Technical Reports Server (NTRS)

    Meyer, W. L.; Zinn, B. T.

    1982-01-01

    Computer codes which were based upon a special integral representation of the external solutions of the Helmholtz equation were upgraded so that they would yield accurate results for the acoustic radiation patterns in the field surrounding an axisymmetric body for nondimensional wave numbers, based on duct radius, of up to twenty. The accuracy of these computer programs was checked by the use of the point source method for the generation of exact solutions and then by comparison with the results of other experimental and theoretical studies. These computer codes were used in a parametric study of the dependence of the radiated sound field on input modal distribution, wave number, and inlet lip shape. The results of this study show that: (1) as the wave number (i.e., cut off ratio) is increased for a given input modal distribution that the acoustic radiation peak moves towards the inlet centerline and becomes more compact (i.e., narrows); (2) as the input mode number is increased for a given cut off ratio the acoustic radiation peak moves away from the inlet centerline and becomes more compact.

  2. Response of a small-turboshaft-engine compression system to inlet temperature distortion

    NASA Technical Reports Server (NTRS)

    Biesiadny, T. J.; Klann, G. A.; Little, J. K.

    1984-01-01

    An experimental investigation was conducted into the response of a small-turboshaft-engine compression system to steady-state and transient inlet temperature distortions. Transient temperature ramps range from less than 100 K/sec to above 610 K/sec and generated instantaneous temperatures to 420 K above ambient. Steady-state temperature distortion levels were limited by the engine hardware temperature list. Simple analysis of the steady-state distortion data indicated that a particle separator at the engine inlet permitted higher levels of temperature distortion before onset of compressor surge than would be expected without the separator.

  3. An engine trade study for a supersonic STOVL fighter-attack aircraft, volume 1

    NASA Technical Reports Server (NTRS)

    Beard, B. B.; Foley, W. H.

    1982-01-01

    The best main engine for an advanced STOVL aircraft flight demonstrator was studied. The STOVL aircraft uses ejectors powered by engine bypass flow together with vectored core exhaust to achieve vertical thrust capability. Bypass flow and core flow are exhausted through separate nozzles during wingborne flight. Six near term turbofan engines were examined for suitability for this aircraft concept. Fan pressure ratio, thrust split between bypass and core flow, and total thrust level were used to compare engines. One of the six candidate engines was selected for the flight demonstrator configuration. Propulsion related to this aircraft concept was studied. A preliminary candidate for the aircraft reaction control system for hover attitude control was selected. A mathematical model of transfer of bypass thrust from ejectors to aft directed nozzle during the transition to wingborne flight was developed. An equation to predict ejector secondary air flow rate and ram drag is derived. Additional topics discussed include: nozzle area control, ejector to engine inlet reingestion, bypass/core thrust split variation, and gyroscopic behavior during hover.

  4. Analysis of Effects of Inlet Pressure Losses on Performance of Axial-Flow Type Turbojet Engine

    NASA Technical Reports Server (NTRS)

    Sanders, Newell D; Palasics, John

    1948-01-01

    The experimentally determined performance characteristics of an axial-flow turbojet engine have been used to estimate the effects of inlet total-pressure losses on net thrust and specific fuel consumption at a constant engine speed. At low altitudes and flight Mach numbers, inlet pressure losses cause an increase in engine discharge temperature and it is possible that the maximum allowable turbine temperature maybe exceeded. An inlet absolute total-pressure loss of 10 percent will result in a thrust loss of 14 percent and a 15-percent increase in specific fuel consumption based on net thrust. At high altitudes and flight Mach numbers, choking conditions exist in the exhaust nozzle and the inlet pressure losses do not affect the discharge temperatures. Under these conditions, a 10-percent loss in inlet absolute total pressure produces a 22-percent loss in net thrust and a 16-percent increase in specific fuel consumption. If the exhaust-nozzle-outlet area is adjusted to compensate for the effect of inlet losses on discharge temperature in the nonchoking cases (low altitude and Mach numbers), the thrust and fuel consumption will be changed in a manner similar to the results obtained in the choking cases.

  5. Particle trajectory computation on a 3-dimensional engine inlet. Final Report Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Kim, J. J.

    1986-01-01

    A 3-dimensional particle trajectory computer code was developed to compute the distribution of water droplet impingement efficiency on a 3-dimensional engine inlet. The computed results provide the essential droplet impingement data required for the engine inlet anti-icing system design and analysis. The droplet trajectories are obtained by solving the trajectory equation using the fourth order Runge-Kutta and Adams predictor-corrector schemes. A compressible 3-D full potential flow code is employed to obtain a cylindrical grid definition of the flowfield on and about the engine inlet. The inlet surface is defined mathematically through a system of bi-cubic parametric patches in order to compute the droplet impingement points accurately. Analysis results of the 3-D trajectory code obtained for an axisymmetric droplet impingement problem are in good agreement with NACA experimental data. Experimental data are not yet available for the engine inlet impingement problem analyzed. Applicability of the method to solid particle impingement problems, such as engine sand ingestion, is also demonstrated.

  6. Helping Aircraft Engines Lighten Up

    NASA Technical Reports Server (NTRS)

    2004-01-01

    High-temperature polyimide/carbon fiber matrix composites are developed by the Polymers Branch at NASA's Glenn Research Center. These materials can withstand high temperatures and have good processing properties, which make them particularly useful for jet and rocket engines and for components such as fan blades, bushings, and duct segments. Applying polyimide composites as components for aerospace structures can lead to substantial vehicle weight reductions. A typical polyimide composite is made up of layers of carbon or glass fibers glued together by a high-temperature polymer to make the material strong, stiff, and lightweight. Organic molecules containing carbon, nitrogen, oxygen, and hydrogen within the polyimide keep the material s density low, resulting in the light weight. The strength of a component or part made from a polyimide comes mainly from the reinforcing high-strength fibers. The strength of the carbon fibers coupled with the stiffness of polyimides allows engineers to make a very rigid structure without it being massive. Another benefit of a polyimide s suitability for aerospace applications is its reduced need for machining. When polyimide parts are removed from a mold, they are nearly in their final shape. Usually, very little machining is needed before a part is ready for use.

  7. Modal analysis of an aircraft engine fan noise

    NASA Astrophysics Data System (ADS)

    Gorodkova, Natalia; Chursin, Valeriy; Bersenev, Yuliy; Burdakov, Ruslan; Siner, Aleksandr; Viskova, Tatiana

    2016-10-01

    The fan is one of the main noise sources of an aircraft engine. To reduce fan noise and provide liner optimization in the inlet it is necessary to research modal structure of the fan noise. The present paper contains results of acoustic tests on installation for mode generation that consists of 34-channel generator and the inlet updated for mounting of 100 microphones, the experiments were provided in new anechoic chamber of Perm National Research Polytechnic University, the engine with the same inlet was also tested in the open test bench conditions, and results of the fan noise modal structure are presented. For modal structure educting, all 100 channels were synchronously registered in a given frequency range. The measured data were analyzed with PULSE analyzer using fast Fourier transform with a frequency resolution 8..16 Hz. Single modes with numbers from 0 to 35 at frequencies 500; 630; 800; 1000; 1250; 1600 Hz and different combinations of modes at frequencies 1000, 1600, 2000, 2500 Hz were set during tests. Modes with small enough numbers are generated well on the laboratory installation, high-number modes generate additional modes caused by a complicated interference pattern of sound field in the inlet. Open test bench results showed that there are also a lot of harmonic components at frequencies lower than fan BPF. Under 0.65 of cut off there is only one distinct mode, other modes with close and less numbers appear from 0.7 of cut off and above. At power regimes 0.76 and 0.94 of cut off the highest mode also changes from positive to negative mode number area. Numbers of the highest modes change smoothly enough with the growth of power regime. At power regimes with Mach>1 (0.7 of cut off and above) on circumference of blade wheel there is a well-defined noise of shock waves at rotor frequency harmonics that appears at the range between the first rotor frequency and fan blade passing frequency (BPF). It is planned to continue researching of sound field

  8. Aircraft Engine Exhaust Nozzle System for Jet Noise Reduction

    NASA Technical Reports Server (NTRS)

    Thomas, Russell H. (Inventor); Czech, Michael J. (Inventor); Elkoby, Ronen (Inventor)

    2014-01-01

    The aircraft exhaust engine nozzle system includes a fan nozzle to receive a fan flow from a fan disposed adjacent to an engine disposed above an airframe surface of the aircraft, a core nozzle disposed within the fan nozzle and receiving an engine core flow, and a pylon structure connected to the core nozzle and structurally attached with the airframe surface to secure the engine to the aircraft.

  9. Further Evaluation of Blast Tests of an Engine Inlet.

    DTIC Science & Technology

    1979-03-31

    hip (1000 lbf) ne..on WN 4..0 222 X E 43 hip /inch 2 (kni) kilo ponil (hI~a) 6.894 757 XC E +3 ktap ncwton-occond/m 2 (N-sis’) 1.00n 000 x F +2...pressure in blastward inlet at M4ach 0.70. Shock Tube 2. Shock overpressure 2.7 psi ( niom ). 91 1 .60 1 .40 1.20 C CJ 1.00 ~ 0.80 0.60 a. Run 8, W2R-FS =304

  10. Dynamics of the inlet system of a four-stroke engine

    NASA Technical Reports Server (NTRS)

    Boden, R H; Schecter, Harry

    1944-01-01

    Tests were run on a single-cylinder and a multicylinder four-stroke engine in order to determine the effect of the dynamics of the inlet system upon indicated mean effective pressure. Tests on the single-cylinder engine were made at various speeds, inlet valve timings, and inlet pipe lengths. These tests indicated that the indicated mean effective pressure could be raised considerably at any one speed by the use of a suitably long inlet pipe. Tests at other speeds with this length of pipe showed higher indicated mean effective pressure than with a very short pipe, although not so high as could be obtained with the pipe length adjusted for each speed. A general relation was discovered between optimum time of inlet valve closing and pipe length; namely, that longer pipes require later inlet valve closing in order to be fully effective. Tests were also made on three cylinders connected to a single pipe. With this arrangement, increased volumetric efficiency at low speed was obtainable by using a long pipe, but only with a sacrifice of volumetric efficiency at high speed. Volumetric efficiency at high speed was progressively lower as the pipe length was increased.

  11. Theoretical surface velocity distributions on acoustic splitter geometries for an engine inlet

    NASA Technical Reports Server (NTRS)

    Albers, J. A.; Breunlin, D. C.

    1974-01-01

    The potential-flow velocity distributions on several splitter geometries in an engine inlet and their variation with different splitter leading-edge shapes and distances from the inlet highlight were analyzed. The velocity distributions on the inner and outer surfaces of the splitters are presented for low-speed and cruise conditions. At zero incidence angle, the splitter with the 4-to-1 elliptical leading edge had lower peak velocities and velocity gradients than the splitter with the 2-to-1 elliptical leading edge. The velocity gradients decreased as the distance from the inlet highlight to the splitter leading edge was increased. For a given distance, the peak velocity on the splitter inner surface increased with increasing inlet incidence angle. At an incidence angle of 50 deg, the velocity level and gradients on the inner surface of the splitter in the forward position were sufficiently severe to suggest local separation.

  12. Ice Nuclei in Mid-Latitude Cirrus: Preliminary Results from a New Counterflow Virtual Impactor (CVI) Aircraft Inlet

    NASA Astrophysics Data System (ADS)

    Froyd, K. D.; Cziczo, D. J.; Murphy, D. M.; Kulkarni, G.; Lawson, P.

    2011-12-01

    Cirrus cloud properties are strongly governed by the mechanism of ice particle formation and by the number and effectiveness of ambient ice nuclei. Airborne measurements of ice nuclei reveal new nucleation mechanisms, provide constraints on microphysical models, and guide laboratory investigations. For over two decades the Counterflow Virtual Impactor (CVI) inlet has remained the prevailing approach for sampling cloud particles to measure ice nuclei from an aircraft platform. However, traditional CVI inlets have fundamental limitations when operating on high speed aircraft, where only a small fraction of ambient cloud particles are typically sampled. A novel 'folded' CVI was constructed and deployed during the NASA MACPEX 2011 campaign. The flow design of this inlet effectively doubles the CVI length and thereby increases the size range of captured cirrus particles. Additional design elements such as an internal vortex flow, a neon carrier gas, and an infrared laser further improve the capture and evaporation of ice crystals. Preliminary results of ice nuclei composition measured by the PALMS single-particle mass spectrometer are presented from the MACPEX campaign. Examples of ice nuclei from mid-latitude cirrus are shown, including mineral dust, organic-rich aerosol with amine and diacid components, and lead-containing aerosol.

  13. Tribological systems as applied to aircraft engines

    NASA Technical Reports Server (NTRS)

    Buckley, D. H.

    1985-01-01

    Tribological systems as applied to aircraft are reviewed. The importance of understanding the fundamental concepts involved in such systems is discussed. Basic properties of materials which can be related to adhesion, friction and wear are presented and correlated with tribology. Surface processes including deposition and treatment are addressed in relation to their present and future application to aircraft components such as bearings, gears and seals. Lubrication of components with both liquids and solids is discussed. Advances in both new liquid molecular structures and additives for those structures are reviewed and related to the needs of advanced engines. Solids and polymer composites are suggested for increasing use and ceramic coatings containing fluoride compounds are offered for the extreme temperatures encountered in such components as advanced bearings and seals.

  14. Fluid dynamic modeling of junctions in internal combustion engine inlet and exhaust systems

    NASA Astrophysics Data System (ADS)

    Chalet, David; Chesse, Pascal

    2010-10-01

    The modeling of inlet and exhaust systems of internal combustion engine is very important in order to evaluate the engine performance. This paper presents new pressure losses models which can be included in a one dimensional engine simulation code. In a first part, a CFD analysis is made in order to show the importance of the density in the modeling approach. Then, the CFD code is used, as a numerical test bench, for the pressure losses models development. These coefficients depend on the geometrical characteristics of the junction and an experimental validation is made with the use of a shock tube test bench. All the models are then included in the engine simulation code of the laboratory. The numerical calculation of unsteady compressible flow, in each pipe of the inlet and exhaust systems, is made and the calculated engine torque is compared with experimental measurements.

  15. Study of unconventional aircraft engines designed for low energy consumption

    NASA Technical Reports Server (NTRS)

    Gray, D. E.

    1976-01-01

    Declining U.S. oil reserves and escalating energy costs underline the need for reducing fuel consumption in aircraft engines. The most promising unconventional aircraft engines based on their potential for fuel savings and improved economics are identified. The engines installed in both a long-range and medium-range aircraft were evaluated. Projected technology advances are identified and evaluated for their state-of-readiness for application to a commercial transport. Programs are recommended for developing the necessary technology.

  16. Aero-Thermo-Structural Analysis of Inlet for Rocket Based Combined Cycle Engines

    NASA Technical Reports Server (NTRS)

    Shivakumar, K. N.; Challa, Preeti; Sree, Dave; Reddy, Dhanireddy R. (Technical Monitor)

    2000-01-01

    NASA has been developing advanced space transportation concepts and technologies to make access to space less costly. One such concept is the reusable vehicles with short turn-around times. The NASA Glenn Research Center's concept vehicle is the Trailblazer powered by a rocket-based combined cycle (RBCC) engine. Inlet is one of the most important components of the RBCC engine. This paper presents fluid flow, thermal, and structural analysis of the inlet for Mach 6 free stream velocity for fully supersonic and supercritical with backpressure conditions. The results concluded that the fully supersonic condition was the most severe case and the largest stresses occur in the ceramic matrix composite layer of the inlet cowl. The maximum tensile and the compressive stresses were at least 3.8 and 3.4, respectively, times less than the associated material strength.

  17. Damage Propagation Modeling for Aircraft Engine Prognostics

    NASA Technical Reports Server (NTRS)

    Saxena, Abhinav; Goebel, Kai; Simon, Don; Eklund, Neil

    2008-01-01

    This paper describes how damage propagation can be modeled within the modules of aircraft gas turbine engines. To that end, response surfaces of all sensors are generated via a thermo-dynamical simulation model for the engine as a function of variations of flow and efficiency of the modules of interest. An exponential rate of change for flow and efficiency loss was imposed for each data set, starting at a randomly chosen initial deterioration set point. The rate of change of the flow and efficiency denotes an otherwise unspecified fault with increasingly worsening effect. The rates of change of the faults were constrained to an upper threshold but were otherwise chosen randomly. Damage propagation was allowed to continue until a failure criterion was reached. A health index was defined as the minimum of several superimposed operational margins at any given time instant and the failure criterion is reached when health index reaches zero. Output of the model was the time series (cycles) of sensed measurements typically available from aircraft gas turbine engines. The data generated were used as challenge data for the Prognostics and Health Management (PHM) data competition at PHM 08.

  18. 77 FR 1626 - Airworthiness Directives; Various Aircraft Equipped With Rotax Aircraft Engines 912 A Series Engine

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-11

    ... determined the unsafe condition exists and is likely to exist or develop on other products of the same type... 40507; and (2) Certificated in any category. Table 1--Affected Airplanes Type certificate holder Aircraft model Engine model Aeromot-Ind stria AMT-200 912 A2 Mec nico- Metal rgica Ltda. Diamond...

  19. Turboelectric Distributed Propulsion Engine Cycle Analysis for Hybrid-Wing-Body Aircraft

    NASA Technical Reports Server (NTRS)

    Felder, James L.; Kim, Hyun Dae; Brown, Gerald V.

    2009-01-01

    possibilities. The Boeing N2 hybrid-wing-body (HWB) is used as a baseline aircraft for this study. The two pylon mounted conventional turbofans are replaced by two wing-tip mounted turboshaft engines, each driving a superconducting generator. Both generators feed a common electrical bus which distributes power to an array of superconducting motor-driven fans in a continuous nacelle centered along the trailing edge of the upper surface of the wing-body. A key finding was that traditional inlet performance methodology has to be modified when most of the air entering the inlet is boundary layer air. A very thorough and detailed propulsion/airframe integration (PAI) analysis is required at the very beginning of the design process since embedded engine inlet performance must be based on conditions at the inlet lip rather than freestream conditions. Examination of a range of fan pressure ratios yielded a minimum Thrust-specific-fuel-consumption (TSFC) at the aerodynamic design point of the vehicle (31,000 ft /Mach 0.8) between 1.3 and 1.35 FPR. We deduced that this was due to the higher pressure losses prior to the fan inlet as well as higher losses in the 2-D inlets and nozzles. This FPR is likely to be higher than the FPR that yields a minimum TSFC in a pylon mounted engine. 1

  20. Parametric Data from a Wind Tunnel Test on a Rocket-Based Combined-Cycle Engine Inlet

    NASA Technical Reports Server (NTRS)

    Fernandez, Rene; Trefny, Charles J.; Thomas, Scott R.; Bulman, Mel J.

    2001-01-01

    A 40-percent scale model of the inlet to a rocket-based combined-cycle (RBCC) engine was tested in the NASA Glenn Research Center 1- by 1-Foot Supersonic Wind Tunnel (SWT). The full-scale RBCC engine is scheduled for test in the Hypersonic Tunnel Facility (HTF) at NASA Glenn's Plum Brook Station at Mach 5 and 6. This engine will incorporate the configuration of this inlet model which achieved the best performance during the present experiment. The inlet test was conducted at Mach numbers of 4.0, 5.0, 5.5, and 6.0. The fixed-geometry inlet consists of an 8 deg.. forebody compression plate, boundary layer diverter, and two compressive struts located within 2 parallel sidewalls. These struts extend through the inlet, dividing the flowpath into three channels. Test parameters investigated included strut geometry, boundary layer ingestion, and Reynolds number (Re). Inlet axial pressure distributions and cross-sectional Pitot-pressure surveys at the base of the struts were measured at varying back-pressures. Inlet performance and starting data are presented. The inlet chosen for the RBCC engine self-started at all Mach numbers from 4 to 6. Pitot-pressure contours showed large flow nonuniformity on the body-side of the inlet. The inlet provided adequate pressure recovery and flow quality for the RBCC cycle even with the flow separation.

  1. Status of the Combined-Cycle Engine Large-Scale Inlet Mode Transition Experiment

    NASA Technical Reports Server (NTRS)

    Slater, John W.; Saunders, J. Dave

    2011-01-01

    The Large-Scale Inlet Mode Transition (LIMX) experiment is currently being conducted in the 10x10 foot supersonic wind tunnel at the NASA Glenn Research Center. The experiment has involved the efforts of a team for over four years to get to the first phase of testing, which is examining the aerodynamic characteristics of the inlet. The LIMX inlet involves dual flowpaths: one to provide flow to a turbine engine and one to provide flow to a dual-mode ramjet/scramjet. A rotating splitter cowl can close off the turbine flowpath, which would occur as the propulsion system transitions from turbine power to ramjet/scramjet power at Mach 4. The first phase of the experiment will simulate the turbine and ramjet/scramjet flows using cold pipes with flow rates controlled by mass-flow plugs. Much of the testing will characterize the performance of the turbine flowpath (total pressure recovery and distortion at the engine face location) as factors such as bleed rates and configuration and vortex generators are varied during the inlet mode transition. The performance of the inlet will also be examined at off-design Mach numbers (2.5-3.0) and at angle-of-attack.

  2. 77 FR 22187 - Technical Amendment; Airworthiness Standards-Aircraft Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-13

    ... Federal Aviation Administration 14 CFR Part 33 Technical Amendment; Airworthiness Standards--Aircraft.... SUMMARY: This amendment corrects a number of errors in the airworthiness standards for aircraft engine... additional burden on any person. List of Subjects 14 CFR Part 33 Air transportation, Aircraft,...

  3. Effect of spatial inlet temperature and pressure distortion on turbofan engine stability

    NASA Technical Reports Server (NTRS)

    Mehalic, Charles M.

    1988-01-01

    The effects of circumferential and radial inlet temperature distortion, circumferential pressure distortion, and combined temperature and pressure distortion on the stability of an advanced turbofan engine were investigated experimentally at simulated altitude conditions. With circumferential and radial inlet temperature distortion, a flow instability generated by the fan operating near stall caused the high-pressure compressor to surge at, or near, the same time as the fan. The effect of combined distortion was dependent on the relative location of the high-temperature and low-pressure regions; high-pressure compressor stalls occurred when the regions coincided, and fan stalls occurred with the regions separated.

  4. Investigation of the stall-induced shock wave (hammershock) at the inlet to the engine

    NASA Technical Reports Server (NTRS)

    Kurkov, A. P.; Soeder, R. H.; Moss, J. E.

    1974-01-01

    The peak static pressures measured at the inlet to the engine during stall are presented for a turbojet and two turbofan engines. It is shown for one turbofan and the turbojet that the static pressure ratio across the hammershock does not exceed significantly the normal shock pressure ratio necessary to stop the flow. The second turbofan engine did not follow this rule. Possible reasons for the departure are discussed. For the two turbofan engines the influence of the stall method on the hammershock intensity was investigated. Data related to the spatial distribution of pressure in the hammershock are also presented.

  5. Integrated engine-generator concept for aircraft electric secondary power

    NASA Technical Reports Server (NTRS)

    Secunde, R. R.; Macosko, R. P.; Repas, D. S.

    1972-01-01

    The integrated engine-generator concept of locating an electric generator inside an aircraft turbojet or turbofan engine concentric with, and driven by, one of the main engine shafts is discussed. When properly rated, the generator can serve as an engine starter as well as a generator of electric power. The electric power conversion equipment and generator controls are conveniently located in the aircraft. Preliminary layouts of generators in a large engine together with their physical sizes and weights indicate that this concept is a technically feasible approach to aircraft secondary power.

  6. 78 FR 65554 - Exhaust Emission Standards for New Aircraft Turbine Engines and Identification Plate for Aircraft...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-01

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Parts 34 and 45 RIN 2120-AK15 Exhaust Emission Standards for New Aircraft Turbine Engines and Identification Plate for Aircraft Engines Correction In rule document 2013-24712, appearing on pages 63015-63017...

  7. Advanced Shock Position Control for Mode Transition in a Turbine Based Combined Cycle Engine Inlet Model

    NASA Technical Reports Server (NTRS)

    Csank, Jeffrey T.; Stueber, Thomas J.

    2013-01-01

    A dual flow-path inlet system is being tested to evaluate methodologies for a Turbine Based Combined Cycle (TBCC) propulsion system to perform a controlled inlet mode transition. Prior to experimental testing, simulation models are used to test, debug, and validate potential control algorithms. One simulation package being used for testing is the High Mach Transient Engine Cycle Code simulation, known as HiTECC. This paper discusses the closed loop control system, which utilizes a shock location sensor to improve inlet performance and operability. Even though the shock location feedback has a coarse resolution, the feedback allows for a reduction in steady state error and, in some cases, better performance than with previous proposed pressure ratio based methods. This paper demonstrates the design and benefit with the implementation of a proportional-integral controller, an H-Infinity based controller, and a disturbance observer based controller.

  8. Effects of Inlet Icing on Performance of Axial-flow Turbojet Engine in Natural Icing Conditions

    NASA Technical Reports Server (NTRS)

    Acker, Loren W; Kleinknecht, Kenneth S

    1950-01-01

    A flight investigation in natural icing conditions was conducted to determine the effect of inlet ice formations on the performance of axial-flow turbojet engines. The results are presented for icing conditions ranging from a liquid-water content of 0.1 to 0.9 gram per cubic meter and water-droplet size from 10 to 27 microns at ambient-air temperature from 13 to 26 degrees F. The data show time histories of jet thrust, air flow, tail-pipe temperature, compressor efficiency, and icing parameters for each icing encounter. The effect of inlet-guide-vane icing was isolated and shown to account for approximately one-half the total reduction in performance caused by inlet icing.

  9. Shuttle Centaur engine cooldown evaluation and effects of expanded inlets on start transient

    NASA Technical Reports Server (NTRS)

    1987-01-01

    As part of the integration of the RL10 engine into the Shuttle Centaur vehicle, a satisfactory method of conditioning the engine to operating temperatures had to be established. This procedure, known as cooldown, is different from the existing Atlas Centaur due to vehicle configuration and mission profile differenced. The program is described, and the results of a Shuttle Centaur cooldown program are reported. Mission peculiarities cause substantial variation in propellant inlet conditions between the substantiated Atlas Centaur and Shuttle Centaur with the Shuttle Centaur having much larger variation in conditions. A test program was conducted to demonstrate operation of the RL10 engine over the expanded inlet conditions. As a result of this program, the Shuttle Centaur requirements were proven satisfactory. Minor configuration changes incorporated as a result of this program provide substantial reduction in cooldown propellant consumption.

  10. A study on vortex flow control of inlet distortion in the re-engined 727-100 center inlet duct using computational fluid dynamics

    NASA Technical Reports Server (NTRS)

    Anderson, Bernhard H.; Huang, Pao S.; Paschal, William A.; Cavatorta, Enrico

    1992-01-01

    Computational fluid dynamics was used to investigate the management of inlet distortion by the introduction of discrete vorticity sources at selected locations in the inlet for the purpose of controlling secondary flow. These sources of vorticity were introduced by means of vortex generators. A series of design observations were made concerning the importance of various vortex generator design parameters in minimizing engine face circumferential distortion. The study showed that vortex strength, generator scale, and secondary flow field structure have a complicated and interrelated influence on the engine face distortion, over and above the initial geometry and arrangement of the generators. The installed vortex generator performance was found to be a function of three categories of variables: the inflow conditions, the aerodynamic characteristics associated with the inlet duct, and the design parameters related to the geometry, arrangement, and placement of the vortex generators within the outlet duct itself.

  11. A study on vortex flow control on inlet distortion in the re-engined 727-100 center inlet duct using computational fluid dynamics

    NASA Technical Reports Server (NTRS)

    Anderson, Bernhard H.; Huang, Pao S.; Paschal, William A.; Cavatorta, Enrico

    1992-01-01

    Computational fluid dynamics was used to investigate the management of inlet distortion by the introduction of discrete vorticity sources at selected locations in the inlet for the purpose of controlling secondary flow. These sources of vorticity were introduced by means of vortex generators. A series of design observations were made concerning the importance of various vortex generator design parameters in minimizing engine face circumferential distortion. The study showed that vortex strength, generator scale, and secondary flow field structure have a complicated and interrelated influence on the engine face distortion, over and above the initial geometry and arrangement of the generators. The installed vortex generator performance was found to be a function of three categories of variables: the inflow conditions, the aerodynamic characteristics associated with the inlet duct, and the design parameters related to the geometry, arrangement, and placement of the vortex generators within the outlet duct itself.

  12. Noise suppression by an acoustically treated three-ring inlet on a TF-34 engine

    NASA Technical Reports Server (NTRS)

    Minner, G. L.; Goldman, R. G.; Heidelberg, L. J.

    1976-01-01

    Acoustic performance tests were conducted with a three-ring inlet noise suppressor designed for a TF-34 engine. For all tests the aft noise sources were highly suppressed. The measured inlet suppression was large, reaching levels greater than 30 db at the peak. Comparisons of the data and the performance predictions were in reasonably good agreement. The frequency of peak attenuation was well predicted; the magnitude and spectral shape were reasonably well predicted. Agreement was best when the distribution of sound energy across the inlet was taken into account in the performance predictions. Tests in which the length of treatment was varied showed an orderly progression of attenuation with length; performance predictions for the different lengths also showed an orderly progression with length. At the highest speed of the engine, multiple pure tones were present throughout the spectrum in the source noise signature. These tones were effectively suppressed by the inlet liner, even at low frequencies, although the liner was designed to work best at the blade-passing frequency.

  13. Microfog lubrication for aircraft engine bearings

    NASA Technical Reports Server (NTRS)

    Rosenlieb, J. W.

    1976-01-01

    An analysis and system study was performed to provide design information regarding lubricant and coolant flow rates and flow paths for effective utilization of the lubricant and coolant in a once through bearing oil mist (microfog) and coolant air system. Both static and dynamic tests were performed. Static tests were executed to evaluate and calibrate the mist supply system. A total of thirteen dynamic step speed bearing tests were performed using four different lubricants and several different mist and air supply configurations. The most effective configuration consisted of supplying the mist and the major portion of the cooling air axially through the bearing. The results of these tests have shown the feasibility of using a once through oil mist and cooling air system to lubricate and cool a high speed, high temperature aircraft engine mainshaft bearing.

  14. Rocket-Based Combined Cycle Engine Technology Development: Inlet CFD Validation and Application

    NASA Technical Reports Server (NTRS)

    DeBonis, J. R.; Yungster, S.

    1996-01-01

    A CFD methodology has been developed for inlet analyses of Rocket-Based Combined Cycle (RBCC) Engines. A full Navier-Stokes analysis code, NPARC, was used in conjunction with pre- and post-processing tools to obtain a complete description of the flow field and integrated inlet performance. This methodology was developed and validated using results from a subscale test of the inlet to a RBCC 'Strut-Jet' engine performed in the NASA Lewis 1 x 1 ft. supersonic wind tunnel. Results obtained from this study include analyses at flight Mach numbers of 5 and 6 for super-critical operating conditions. These results showed excellent agreement with experimental data. The analysis tools were also used to obtain pre-test performance and operability predictions for the RBCC demonstrator engine planned for testing in the NASA Lewis Hypersonic Test Facility. This analysis calculated the baseline fuel-off internal force of the engine which is needed to determine the net thrust with fuel on.

  15. 76 FR 72128 - Airworthiness Directives; Thielert Aircraft Engines GmbH (TAE) Reciprocating Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-22

    ... Directives; Thielert Aircraft Engines GmbH (TAE) Reciprocating Engines AGENCY: Federal Aviation... engines installed on, but not limited to, Diamond Aircraft Industries Model DA 42 airplanes. The existing... the PPRV, part number (P/N) 05-7212- E002801, on TAE 125-02-99 engines, from 300 hours to 600...

  16. Computational Fluid Dynamics Analysis Method Developed for Rocket-Based Combined Cycle Engine Inlet

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Renewed interest in hypersonic propulsion systems has led to research programs investigating combined cycle engines that are designed to operate efficiently across the flight regime. The Rocket-Based Combined Cycle Engine is a propulsion system under development at the NASA Lewis Research Center. This engine integrates a high specific impulse, low thrust-to-weight, airbreathing engine with a low-impulse, high thrust-to-weight rocket. From takeoff to Mach 2.5, the engine operates as an air-augmented rocket. At Mach 2.5, the engine becomes a dual-mode ramjet; and beyond Mach 8, the rocket is turned back on. One Rocket-Based Combined Cycle Engine variation known as the "Strut-Jet" concept is being investigated jointly by NASA Lewis, the U.S. Air Force, Gencorp Aerojet, General Applied Science Labs (GASL), and Lockheed Martin Corporation. Work thus far has included wind tunnel experiments and computational fluid dynamics (CFD) investigations with the NPARC code. The CFD method was initiated by modeling the geometry of the Strut-Jet with the GRIDGEN structured grid generator. Grids representing a subscale inlet model and the full-scale demonstrator geometry were constructed. These grids modeled one-half of the symmetric inlet flow path, including the precompression plate, diverter, center duct, side duct, and combustor. After the grid generation, full Navier-Stokes flow simulations were conducted with the NPARC Navier-Stokes code. The Chien low-Reynolds-number k-e turbulence model was employed to simulate the high-speed turbulent flow. Finally, the CFD solutions were postprocessed with a Fortran code. This code provided wall static pressure distributions, pitot pressure distributions, mass flow rates, and internal drag. These results were compared with experimental data from a subscale inlet test for code validation; then they were used to help evaluate the demonstrator engine net thrust.

  17. Development of the Junkers-diesel Aircraft Engine

    NASA Technical Reports Server (NTRS)

    Gasterstadt,

    1930-01-01

    The working process of the Junkers engine has resulted from a series of attempts to attain high performance and to control the necessarily rapid and complete combustion at extremely high speeds. The two main problems of Diesel engines in aircraft are addressed; namely, incomplete combustion and the greater weight of Diesel engine parts compared to gasoline engines.

  18. Combined Cycle Engine Large-Scale Inlet for Mode Transition Experiments: System Identification Rack Hardware Design

    NASA Technical Reports Server (NTRS)

    Thomas, Randy; Stueber, Thomas J.

    2013-01-01

    The System Identification (SysID) Rack is a real-time hardware-in-the-loop data acquisition (DAQ) and control instrument rack that was designed and built to support inlet testing in the NASA Glenn Research Center 10- by 10-Foot Supersonic Wind Tunnel. This instrument rack is used to support experiments on the Combined-Cycle Engine Large-Scale Inlet for Mode Transition Experiment (CCE? LIMX). The CCE?LIMX is a testbed for an integrated dual flow-path inlet configuration with the two flow paths in an over-and-under arrangement such that the high-speed flow path is located below the lowspeed flow path. The CCE?LIMX includes multiple actuators that are designed to redirect airflow from one flow path to the other; this action is referred to as "inlet mode transition." Multiple phases of experiments have been planned to support research that investigates inlet mode transition: inlet characterization (Phase-1) and system identification (Phase-2). The SysID Rack hardware design met the following requirements to support Phase-1 and Phase-2 experiments: safely and effectively move multiple actuators individually or synchronously; sample and save effector control and position sensor feedback signals; automate control of actuator positioning based on a mode transition schedule; sample and save pressure sensor signals; and perform DAQ and control processes operating at 2.5 KHz. This document describes the hardware components used to build the SysID Rack including their function, specifications, and system interface. Furthermore, provided in this document are a SysID Rack effectors signal list (signal flow); system identification experiment setup; illustrations indicating a typical SysID Rack experiment; and a SysID Rack performance overview for Phase-1 and Phase-2 experiments. The SysID Rack described in this document was a useful tool to meet the project objectives.

  19. Laser Doppler techniques for the combined measurement of inlet flow and valve motion in IC engines

    NASA Astrophysics Data System (ADS)

    Gasparetti, M.; Paone, N.; Tomasini, E. P.

    1996-04-01

    A measurement methodology and a test set-up for the experimental investigation of internal combustion engines are presented. This system is based on a laser Doppler anemometer and a laser Doppler vibrometer which measure in a co-ordinated or simultaneous mode both the velocity of the intake flow and the motion of the inlet poppet valve. A synchronized data acquisition procedure allows the use of two optical instruments to analyse the effects of valve jumps and bounces on the inlet flow field. At high rpm, anomalous valve behaviour may appear. Fluid velocity measurements are taken inside the cylinder and the manifold of a motored automotive engine head at different rpm, up to a speed at which anomalous valve behaviour regularly occurs. Velocity data are processed in both time and frequency domains. This measurement system also represents a valuable tool to study resonance phenomena in ducts.

  20. Application of rotor mounted pressure transducers to analysis of inlet turbulence. [flow distortion in turbofan engine inlet

    NASA Technical Reports Server (NTRS)

    Hanson, D. B.

    1976-01-01

    Miniature pressure transducers installed near the leading edge of a fan blade were used to diagnose the non-uniform flow entering a subsonic tip speed turbofan on a static test stand. The pressure response of the blade to the inlet flow variations was plotted in a form which shows the space-time history of disturbances ingested by the rotor. Also, periodically sampled data values were auto- and cross-correlated as if they had been acquired from fixed hot wire anemometers at 150 equally spaced angles around the inlet. With a clean inlet and low wind, evidence of long, narrow turbulence eddies was easily found both in the boundary layer of the fan duct and outside the boundary layer. The role of the boundary layer was to follow and amplify disturbances in the outer flow. These eddies frequently moved around the inlet with a corkscrew motion as they passed through.

  1. Summary of recent investigations of inlet flow distortion effect on engine stability

    NASA Technical Reports Server (NTRS)

    Graber, E. J., Jr.; Braithwaite, W. M.

    1974-01-01

    A review is presented of recent experimental results, analytical procedures and test techniques employed to evaluate the effects of inlet flow distortion on the stability characteristics of representative afterburning turbofan and turbojet compression systems. Circumferential distortions of pressure and temperature, separately and in combination are considered. Resulting engine sensitivity measurements are compared with predictions based on simplified parallel compressor models and with several distortion descriptor parameters.

  2. Determination of the passing efficiency for aerosol chemical species through a typical aircraft-mounted, diffuser-type aerosol inlet system

    NASA Astrophysics Data System (ADS)

    Sheridan, Patrick J.; Norton, Richard B.

    1998-04-01

    To assess the particle transmission efficiency of a conventional aircraft-mounted, diffuser-type inlet (CI), a new design inlet containing an internal filter basket assembly (aerosol filter inlet, or AFI) was constructed. All interior surfaces of the AFI were covered with filter material, and air was actively pulled through these filter walls during aerosol sampling. The AFI was demonstrated in the laboratory to trap nearly all particles entering its nozzle orifice, so it was considered usable as a baseline to judge the performance of other inlets. Wind tunnel studies were conducted at three different wind velocities that approximated typical research aircraft speeds. As wind velocity increased, particle transmission through the CI relative to the AFI decreased, as evidenced by chemical analysis of the filter deposits. Aircraft studies of the two inlets showed that particle transmission varied significantly with the measured species. Typical coarse-particle species such as Ca++, Mg++, Na+ and K+ showed 50-90% mass losses through a conventional diffuser-type inlet/curved intake tube system. Predominantly fine particle species such as SO4= and NH4+ passed the CI system with much higher efficiencies, with aerosol mass losses of 0-26% for most flights. Since the AFI traps nearly all particles aspirated into its nozzle orifice, these values indicate that on average, 80-90% of the SO4= and NH4+ aerosol mass passes through the CI and curved intake tube during airborne sampling. This finding suggests that the capability to sample fine (i.e., submicrometer) aerosols from aircraft is perhaps not as bad as has been previously reported, given that adequate attention is paid to inlet design, location, and orientation issues.

  3. 78 FR 47228 - Airworthiness Directives; Thielert Aircraft Engines GmbH Reciprocating Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-05

    ... Engines GmbH Reciprocating Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of... Thielert Aircraft Engines GmbH TAE 125-01 reciprocating engines. This proposed AD was prompted by a report of engine power loss due to engine coolant contaminating the engine clutch. The design of the...

  4. Computerized systems analysis and optimization of aircraft engine performance, weight, and life cycle costs

    NASA Technical Reports Server (NTRS)

    Fishbach, L. H.

    1979-01-01

    The computational techniques utilized to determine the optimum propulsion systems for future aircraft applications and to identify system tradeoffs and technology requirements are described. The characteristics and use of the following computer codes are discussed: (1) NNEP - a very general cycle analysis code that can assemble an arbitrary matrix fans, turbines, ducts, shafts, etc., into a complete gas turbine engine and compute on- and off-design thermodynamic performance; (2) WATE - a preliminary design procedure for calculating engine weight using the component characteristics determined by NNEP; (3) POD DRG - a table look-up program to calculate wave and friction drag of nacelles; (4) LIFCYC - a computer code developed to calculate life cycle costs of engines based on the output from WATE; and (5) INSTAL - a computer code developed to calculate installation effects, inlet performance and inlet weight. Examples are given to illustrate how these computer techniques can be applied to analyze and optimize propulsion system fuel consumption, weight, and cost for representative types of aircraft and missions.

  5. The 727 airplane side inlet low-speed performance confirmation model test for refanned JT8D engines

    NASA Technical Reports Server (NTRS)

    Schuehle, A. L.

    1974-01-01

    The results of a low-speed wind tunnel test of a 0.3 scale model 727 airplane side inlet for JT8D-100 engines are presented. The objectives of the test were to develop lines for a full-scale flightworthy inlet, to evaluate inlet total pressure recovery and steady-state total pressure distortion, and to obtain model-scale distortion data which can be used in the assessment of the compatibility of the inlet with the JT8D-100 series engines. A secondary objective was to obtain internal/external cowl static pressures for the determination of nacelle loads. Two basic inlet models were tested at static, forward speed, angle-of-attack (inflow angle), and cross-wind conditions. One model was with and one without an acoustic ring. Two modifications to the models were also tested, one with the ring closer to the inlet throat and one with a larger lip. Test measurements consisted of inlet surface static pressure, engine face total pressure, inlet airflow, tunnel total pressure, tunnel total temperature and tunnel velocity. Total pressure traverses were taken directly behind the ring and strut. No dynamic measurements were taken.

  6. Supersonic through-flow fan engine and aircraft mission performance

    NASA Technical Reports Server (NTRS)

    Franciscus, Leo C.; Maldonado, Jaime J.

    1989-01-01

    A study was made to evaluate potential improvement to a commercial supersonic transport by powering it with supersonic through-flow fan turbofan engines. A Mach 3.2 mission was considered. The three supersonic fan engines considered were designed to operate at bypass ratios of 0.25, 0.5, and 0.75 at supersonic cruise. For comparison a turbine bypass turbojet was included in the study. The engines were evaluated on the basis of aircraft takeoff gross weight with a payload of 250 passengers for a fixed range of 5000 N.MI. The installed specific fuel consumption of the supersonic fan engines was 7 to 8 percent lower than that of the turbine bypass engine. The aircraft powered by the supersonic fan engines had takeoff gross weights 9 to 13 percent lower than aircraft powered by turbine bypass engines.

  7. Digital integrated control of a Mach 2.5 mixed-compression supersonic inlet and an augmented mixed-flow turbofan engine

    NASA Technical Reports Server (NTRS)

    Batterton, P. G.; Arpasi, D. J.; Baumbick, R. J.

    1974-01-01

    A digitally implemented integrated inlet-engine control system was designed and tested on a mixed-compression, axisymmetric, Mach 2.5, supersonic inlet with 45 percent internal supersonic area contraction and a TF30-P-3 augmented turbofan engine. The control matched engine airflow to available inlet airflow. By monitoring inlet terminal shock position and over-board bypass door command, the control adjusted engine speed so that in steady state, the shock would be at the desired location and the overboard bypass doors would be closed. During engine-induced transients, such as augmentor light-off and cutoff, the inlet operating point was momentarily changed to a more supercritical point to minimize unstarts. The digital control also provided automatic inlet restart. A variable inlet throat bleed control, based on throat Mach number, provided additional inlet stability margin.

  8. Supercharged two-cycle engines employing novel single element reciprocating shuttle inlet valve mechanisms and with a variable compression ratio

    NASA Technical Reports Server (NTRS)

    Wiesen, Bernard (Inventor)

    2008-01-01

    This invention relates to novel reciprocating shuttle inlet valves, effective with every type of two-cycle engine, from small high-speed single cylinder model engines, to large low-speed multiple cylinder engines, employing spark or compression ignition. Also permitting the elimination of out-of-phase piston arrangements to control scavenging and supercharging of opposed-piston engines. The reciprocating shuttle inlet valve (32) and its operating mechanism (34) is constructed as a single and simple uncomplicated member, in combination with the lost-motion abutments, (46) and (48), formed in a piston skirt, obviating the need for any complex mechanisms or auxiliary drives, unaffected by heat, friction, wear or inertial forces. The reciprocating shuttle inlet valve retains the simplicity and advantages of two-cycle engines, while permitting an increase in volumetric efficiency and performance, thereby increasing the range of usefulness of two-cycle engines into many areas that are now dominated by the four-cycle engine.

  9. Re-engining - The sound case for aircraft noise reduction

    NASA Astrophysics Data System (ADS)

    Goddard, K.

    1991-06-01

    The paper reviews the history of legislation to reduce jet-powered aircraft noise, particularly in the U.S.A. Recently introduced legislation is discussed and the paper goes on to explain the fundamental advantage of re-engining as a means of reducing aircraft noise. Th Rolls-Royce Tay engine is introduced and the two re-engine programs already launched are described. The expected large reductions in noise level which result from re-engining are illustrated. The paper concludes with a discussion on new programs, on the current airline business scene and on some aspects of the economics of re-engining.

  10. The 300 H.P. Benz Aircraft Engine

    NASA Technical Reports Server (NTRS)

    Heller, A

    1921-01-01

    A description is given of the Benz 12-cylinder aircraft engine. The 300 H.P. engine, with the cylinders placed at an angle of 60 degrees not only realizes a long-cherished conception, but has received refinement in detail. It may be described as a perfect example of modern German aircraft engine construction. Here, a detailed description is given of the construction of this engine. Emphasis is placed on the design and construction of the cylinders, pistons, and connecting rods. Also discussed are engine fitting, lubrication, oil pumps, bearings, the oil tank, fuel pump, carburetors, and cooling system.

  11. Analysis of the flow field generated near an aircraft engine operating in reverse thrust. M.S. Thesis

    NASA Technical Reports Server (NTRS)

    Ledwith, W. A., Jr.

    1972-01-01

    A computer solution is developed to the exhaust gas reingestion problem for aircraft operating in the reverse thrust mode on a crosswind-free runway. The computer program determines the location of the inlet flow pattern, whether the exhaust efflux lies within the inlet flow pattern or not, and if so, the approximate time before the reversed flow reaches the engine inlet. The program is written so that the user is free to select discrete runway speeds or to study the entire aircraft deceleration process for both the far field and cross-ingestion problems. While developed with STOL applications in mind, the solution is equally applicable to conventional designs. The inlet and reversed jet flow fields involved in the problem are assumed to be noninteracting. The nacelle model used in determining the inlet flow field is generated using an iterative solution to the Neuman problem from potential flow theory while the reversed jet flow field is adapted using an empirical correlation from the literature. Sample results obtained using the program are included.

  12. Numerical Investigation of Engine Inlet Vane Hot-Air Anti-Icing System with Surface Air Film

    NASA Astrophysics Data System (ADS)

    Ma, Hui; Chen, Weijian; Zhang, Dalin

    The inlet vane of aircraft engine needs to be equipped with anti-icing system to prevent ice accretion on the leading edge due to flight safety requirements, and the engine bleed hot-air is mostly used to heat the vane surface in anti-icing system. In order to save the energy consumption, a new anti-icing structure was developed and investigated with numerical simulation. Besides the use of small tunnels to enhance the heat transfer characteristics, a narrow gap was opened and assigned on the vane surface at the end of the anti-icing tunnels, and the exhaust hot-air was released from the gap to form an air film on the outside surface, which was supposed to prevent the droplets from impinging to the surface and sweep the droplets away. The droplets impingement on the vane surface was investigated by solving the 3D Eulerian air/droplets twophase model, and the impingement results were compared with the original system. Meanwhile, the thermodynamic analysis of the anti-icing system was presented in this paper. The results indicate that the air film is effective to decrease the droplets impingement area, and the new structure could provide more heat flux for anti-icing than the regular anti-icing structure.

  13. 14 CFR 21.128 - Tests: aircraft engines.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Tests: aircraft engines. 21.128 Section 21.128 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS Production Under Type Certificate § 21.128 Tests:...

  14. 14 CFR 21.128 - Tests: aircraft engines.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Tests: aircraft engines. 21.128 Section 21.128 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS Production Under Type Certificate § 21.128 Tests:...

  15. 14 CFR 21.128 - Tests: aircraft engines.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Tests: aircraft engines. 21.128 Section 21.128 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS Production Under Type Certificate § 21.128 Tests:...

  16. Experimental Measurement of Transonic Fan Wake Response to Uniform and Simulated Boundary Layer Ingesting Inlet Flows

    NASA Technical Reports Server (NTRS)

    O'Brien, Walter F.; Ferrar, Anthony M.; Arend, David

    2011-01-01

    BWB Aircraft with embedded engines and BLI inlets offer attractive advantages in terms of reduced noise from engines and increased range and fuel economy. The BLI inlet produces inlet distortion patterns that can reduce fan performance and stall margin, and can produce undesirable forced responses. Knowledge of the dynamic response of fan flow when subjected to flow distortions of the type produced by BLI inlets is important for the design of distortion tolerant fans. This project is investigating fan response to flow distortion by measuring the response of the fan of a JT15D engine to a flow pattern following the results of the NASA Inlet A BLI wind tunnel tests.

  17. 76 FR 68636 - Airworthiness Directives; Thielert Aircraft Engines GmbH (TAE) Reciprocating Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-07

    ...-01] RIN 2120-AA64 Airworthiness Directives; Thielert Aircraft Engines GmbH (TAE) Reciprocating Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule; request for comments. SUMMARY: We are superseding an existing airworthiness directive (AD) for Thielert Aircraft Engines...

  18. The design and flight test of an engine inlet bulk acoustic liner

    NASA Technical Reports Server (NTRS)

    Lester, H. C.; Preisser, J. S.; Parrott, T. L.

    1983-01-01

    This paper summarizes the design, fabrication and flight evaluation of a Kevlar acoustic liner configuration for a JT15D turbofan engine. The liner was designed to suppress, by a measurable amount, a dominant (13,0) BPF tone. This tone or spinning mode was produced for research purposes by installing 41 circumferentially distributed small diameter rods upstream of the 28 fan blades. Duct liner attenuations calculated by a finite element procedure were compared to far field power (insertion) losses deduced from flight data. The finite element program modeled the variable geometry of the JT15D inlet and used a uniform flow with a boundary layer roll-off to model the inlet flow field. Calculated liner losses were generally conservative. That is, measured far field power losses were generally greater than attenuations calculated by the finite element computer program.

  19. Comparison of Engine/Inlet Distortion Measurements with MEMS and ESP Pressure Sensors

    NASA Technical Reports Server (NTRS)

    Soto, Hector L.; Hernandez, Corey D.

    2004-01-01

    A study of active-flow control in a small-scale boundary layer ingestion inlet was conducted at the NASA Langley Basic Aerodynamic Research Tunnel (BART). Forty MEMS pressure sensors, in a rake style configuration, were used to examine both the mean (DC) and high frequency (AC) components of the total pressure across the inlet/engine interface plane. The mean component was acquired and used to calculate pressure distortion. The AC component was acquired separately, at a high sampling rate, and is used to study the unsteady effects of the active-flow control. An identical total pressure rake, utilizing an Electronically Scanned Pressure (ESP) system, was also used to calculate distortion; a comparison of the results obtained using the two rakes is presented.

  20. Flutter of aircraft engine turbine blades

    NASA Astrophysics Data System (ADS)

    Panovsky, Josef, Jr.

    1997-11-01

    The goal of this research is to eliminate occurrences of flutter of low-pressure turbine blades in aircraft engines. Fundamental unsteady aerodynamic experiments in an annular cascade plus correlating analyses are conducted to improve the understanding of the flutter mechanism in these blades and to identify the key flutter parameters. The use of two- and three-dimensional linearized Euler methods for the calculation of the unsteady pressures due to the blade motion are validated through detailed comparison with the experimental data. Unexpected features of the steady and unsteady flows are also investigated using these computational tools. The validated computer codes are used to extend the range of the experimental data in a series of parametric studies, where the influence of mode shape, reduced frequency, and blade loading are investigated. Mode shape is identified as the most important contributor to determining the stability of a blade design. A new stability parameter is introduced to gain additional insight into the key contributors to flutter. This stability parameter is derived from the influence coefficient representation of the cascade, and includes only contributions from the reference blade and its immediate neighbors. This has the effect of retaining the most important contributions while filtering out terms of less significance. Design rules for the preliminary concept phase and procedures for the detailed analysis phase of the typical blade design process are defined. Utilization of these procedures will lead to blade designs which are free of flutter.

  1. Calculation of odour emissions from aircraft engines at Copenhagen Airport.

    PubMed

    Winther, Morten; Kousgaard, Uffe; Oxbøl, Arne

    2006-07-31

    In a new approach the odour emissions from aircraft engines at Copenhagen Airport are calculated using actual fuel flow and emission measurements (one main engine and one APU: Auxiliary Power Unit), odour panel results, engine specific data and aircraft operational data for seven busy days. The calculation principle assumes a linear relation between odour and HC emissions. Using a digitalisation of the aircraft movements in the airport area, the results are depicted on grid maps, clearly reflecting aircraft operational statistics as single flights or total activity during a whole day. The results clearly reflect the short-term temporal fluctuations of the emissions of odour (and exhaust gases). Aircraft operating at low engine thrust (taxiing, queuing and landing) have a total odour emission share of almost 98%, whereas the shares for the take off/climb out phases (2%) and APU usage (0.5%) are only marginal. In most hours of the day, the largest odour emissions occur, when the total amount of fuel burned during idle is high. However, significantly higher HC emissions for one specific engine cause considerable amounts of odour emissions during limited time periods. The experimentally derived odour emission factor of 57 OU/mg HC is within the range of 23 and 110 OU/mg HC used in other airport odour studies. The distribution of odour emission results between aircraft operational phases also correspond very well with the results for these other studies. The present study uses measurement data for a representative engine. However, the uncertainties become large when the experimental data is used to estimate the odour emissions for all aircraft engines. More experimental data is needed to increase inventory accuracy, and in terms of completeness it is recommended to make odour emission estimates also for engine start and the fuelling of aircraft at Copenhagen Airport in the future.

  2. Design-of-experiments to Reduce Life-cycle Costs in Combat Aircraft Inlets

    NASA Technical Reports Server (NTRS)

    Anderson, Bernhard H.; Baust, Henry D.; Agrell, Johan

    2003-01-01

    It is the purpose of this study to demonstrate the viability and economy of Design- of-Experiments (DOE), to arrive at micro-secondary flow control installation designs that achieve optimal inlet performance for different mission strategies. These statistical design concepts were used to investigate the properties of "low unit strength" micro-effector installation. "Low unit strength" micro-effectors are micro-vanes, set a very low angle-of incidence, with very long chord lengths. They are designed to influence the neat wall inlet flow over an extended streamwise distance. In this study, however, the long chord lengths were replicated by a series of short chord length effectors arranged in series over multiple bands of effectors. In order to properly evaluate the performance differences between the single band extended chord length installation designs and the segmented multiband short chord length designs, both sets of installations must be optimal. Critical to achieving optimal micro-secondary flow control installation designs is the understanding of the factor interactions that occur between the multiple bands of micro-scale vane effectors. These factor interactions are best understood and brought together in an optimal manner through a structured DOE process, or more specifically Response Surface Methods (RSM).

  3. Fiber-Optic Circuits For Aircraft Engine Controls

    NASA Astrophysics Data System (ADS)

    Glomb, Walter L.

    1987-12-01

    This paper describes environmental effects which impact the design of interfaces to fiber-optic sensors and data buses in aircraft engine controls. Emphasis is placed on selection of components and designs which maintain their performance and reliability in the harsh environment of an electronics enclosure mounted on a modern aircraft turbine engine. Particular attention is given to the effects of temperature on electro-optical component and system performance. The main conclusion is that electro-optical interfaces to a variety of fiber-optic systems can be installed in an engine-mounted control if the designs and components are selected after careful analysis of the effects of the engine environment.

  4. Effects on inlet technology on cruise speed selection

    NASA Technical Reports Server (NTRS)

    Bangert, L. H.; Santman, D. M.; Horie, G.; Miller, L. D.

    1980-01-01

    The impact of cruise speed on technology level for certain aircraft components is examined. External-compression inlets were compared with mixed compression, self starting inlets at cruise Mach numbers of 2.0 and 2.3. Inlet engine combinations that provided the greatest aircraft range were identified. Results show that increased transonic to cruise corrected air flow ratio gives decreased range for missions dominated by supersonic cruise. It is also found important that inlets be designed to minimize spillage drag at subsonic cruise, because of the need for efficient performance for overland operations. The external compression inlet emerged as the probable first choice at Mach 2.0, while the self starting inlet was the probable first choice at Mach 2.3. Airframe propulsion system interference effects were significant, and further study is needed to assess the existing design methods and to develop improvements.

  5. A Roadmap for Aircraft Engine Life Extending Control

    NASA Technical Reports Server (NTRS)

    Guo, Ten-Huei

    2001-01-01

    The concept of Aircraft Engine Life Extending Control is introduced. A brief description of the tradeoffs between performance and engine life are first explained. The overall goal of the life extending controller is to reduce the engine operating cost by extending the on-wing engine life while improving operational safety. The research results for NASA's Rocket Engine life extending control program are also briefly described. Major building blocks of the Engine Life Extending Control architecture are examined. These blocks include: life prediction models, engine operation models, stress and thermal analysis tools, control schemes, and intelligent control systems. The technology areas that would likely impact the successful implementation of an aircraft engine life extending control are also briefly described. Near, intermediate, and long term goals of NASA's activities are also presented.

  6. Effect of inlet disturbances on fan inlet noise during a static test

    NASA Technical Reports Server (NTRS)

    Bekofske, K. L.; Sheer, R. E., Jr.; Wang, J. C. F.

    1977-01-01

    Measurements of fan rotor inlet noise taken during static test situations are at variance with aircraft engine flight data. In particular, static tests generally yield a significantly higher tone at blade passage frequency than that measured during flight. To explain this discrepancy, the extent of the influence of inlet ground vortices and large-scale inlet turbulence on the forward-radiated fan noise measured at a static test facility was investigated. While such inlet disturbances were generated intentionally in an anechoic test chamber, far-field acoustic measurements and inlet flow-field hot-film mappings of a fan rotor were obtained. Experimental results indicate that the acoustic effect of such disturbances appears to be less severe for supersonic than for subsonic tip speeds. Further, a reverse flow that occurs on the exterior cowl in static test facilities appears to be an additional prime candidate for creating inlet disturbances and causing variance between flight and static acoustic data.

  7. Dynamic and Transient Performance of Turbofan/Turboshaft Convertible Engine With Variable Inlet Guide Vanes

    NASA Technical Reports Server (NTRS)

    McArdle, Jack G.; Barth, Richard L.; Wenzel, Leon M.; Biesiadny, Thomas J.

    1996-01-01

    A convertible engine called the CEST TF34, using the variable inlet guide vane method of power change, was tested on an outdoor stand at the NASA Lewis Research Center with a waterbrake dynamometer for the shaft load. A new digital electronic system, in conjunction with a modified standard TF34 hydromechanical fuel control, kept engine operation stable and safely within limits. All planned testing was completed successfully. Steady-state performance and acoustic characteristics were reported previously and are referenced. This report presents results of transient and dynamic tests. The transient tests measured engine response to several rapid changes in thrust and torque commands at constant fan (shaft) speed. Limited results from dynamic tests using the pseudorandom binary noise technique are also presented. Performance of the waterbrake dynamometer is discussed in an appendix.

  8. Development of the HIDEC inlet integration mode. [Highly Integrated Digital Electronic Control

    NASA Technical Reports Server (NTRS)

    Chisholm, J. D.; Nobbs, S. G.; Stewart, J. F.

    1990-01-01

    The Highly Integrated Digital Electronic Control (HIDEC) development program conducted at NASA-Ames/Dryden will use an F-15 test aircraft for flight demonstration. An account is presently given of the HIDEC Inlet Integration mode's design concept, control law, and test aircraft implementation, with a view to its performance benefits. The enhancement of performance is a function of the use of Digital Electronic Engine Control corrected engine airflow computations to improve the scheduling of inlet ramp positions in real time; excess thrust can thereby be increased by 13 percent at Mach 2.3 and 40,000 ft. Aircraft supportability is also improved through the obviation of inlet controllers.

  9. Aerodynamic and acoustic behavior of a YF-12 inlet at static conditions

    NASA Technical Reports Server (NTRS)

    Bangert, L. H.; Feltz, E. P.; Godby, L. A.; Miller, L. D.

    1981-01-01

    An aeroacoustic test program to determine the cause of YF-12 inlet noise suppression was performed with a YF-12 aircraft at ground static conditions. Data obtained over a wide range of engine speeds and inlet configurations are reported. Acoustic measurements were made in the far field and aerodynamic and acoustic measurements were made inside the inlet. The J-58 test engine was removed from the aircraft and tested separately with a bellmouth inlet. The far field noise level was significantly lower for the YF-12 inlet than for the bellmouth inlet at engine speeds above 5500 rpm. There was no evidence that noise suppression was caused by flow choking. Multiple pure tones were reduced and the spectral peak near the blade passing frequency disappeared in the region of the spike support struts at engine speeds between 6000 and 6600 rpm.

  10. 78 FR 70216 - Airworthiness Directives; Thielert Aircraft Engines GmbH Reciprocating Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-25

    ... Engines GmbH Reciprocating Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: We are adopting a new airworthiness directive (AD) for all Thielert Aircraft Engines GmbH TAE 125-01 reciprocating engines. This AD requires applying sealant to close the engine clutch...

  11. Intelligent Life-Extending Controls for Aircraft Engines Studied

    NASA Technical Reports Server (NTRS)

    Guo, Ten-Huei

    2005-01-01

    Current aircraft engine controllers are designed and operated to provide desired performance and stability margins. Except for the hard limits for extreme conditions, engine controllers do not usually take engine component life into consideration during the controller design and operation. The end result is that aircraft pilots regularly operate engines under unnecessarily harsh conditions to strive for optimum performance. The NASA Glenn Research Center and its industrial and academic partners have been working together toward an intelligent control concept that will include engine life as part of the controller design criteria. This research includes the study of the relationship between control action and engine component life as well as the design of an intelligent control algorithm to provide proper tradeoffs between performance and engine life. This approach is expected to maintain operating safety while minimizing overall operating costs. In this study, the thermomechanical fatigue (TMF) of a critical component was selected to demonstrate how an intelligent engine control algorithm can significantly extend engine life with only a very small sacrifice in performance. An intelligent engine control scheme based on modifying the high-pressure spool speed (NH) was proposed to reduce TMF damage from ground idle to takeoff. The NH acceleration schedule was optimized to minimize the TMF damage for a given rise-time constraint, which represents the performance requirement. The intelligent engine control scheme was used to simulate a commercial short-haul aircraft engine.

  12. Lightweight, low compression aircraft diesel engine. [converting a spark ignition engine to the diesel cycle

    NASA Technical Reports Server (NTRS)

    Gaynor, T. L.; Bottrell, M. S.; Eagle, C. D.; Bachle, C. F.

    1977-01-01

    The feasibility of converting a spark ignition aircraft engine to the diesel cycle was investigated. Procedures necessary for converting a single cylinder GTS10-520 are described as well as a single cylinder diesel engine test program. The modification of the engine for the hot port cooling concept is discussed. A digital computer graphics simulation of a twin engine aircraft incorporating the diesel engine and Hot Fort concept is presented showing some potential gains in aircraft performance. Sample results of the computer program used in the simulation are included.

  13. Icing tunnel tests of Electro-Impulse De-Icing of an engine inlet and high-speed wings

    NASA Technical Reports Server (NTRS)

    Zumwalt, G. W.

    1985-01-01

    A brief review is given of four earlier tests in the NASA Lewis Icing Research Tunnel and of flight tests in NASA's Icing Research Aircraft and in a Cessna 206 airplane. Details are given of recent icing tunnel tests of thicker-skinned wings, a Gates Learjet, a composite leading edge, and a Boeing 767, and of a Falcon Fanjet engine inlet. These were tested at speeds from 87 to 220 knots, air temperatures from -2 to -15 C, LWC values of 0.6 to 2.4 grams/cu meter, and median droplet diameters from 12 to 20 microns. Energy requirements are reported, as well as conclusions from comparisons of several Electro-Impulse De-Icing coil system designs. Fundamental studies of the structural dynamics and ice shedding of a 12.7 cm (5 inch) diameter semicylinder are described. Some potential problem areas are discussed: fatigue of skin and coil mountings, system weight and cost, electro-magnetic interference and noise.

  14. A Turbine Based Combined Cycle Engine Inlet Model and Mode Transition Simulation Based on HiTECC Tool

    NASA Technical Reports Server (NTRS)

    Csank, Jeffrey; Stueber, Thomas

    2012-01-01

    An inlet system is being tested to evaluate methodologies for a turbine based combined cycle propulsion system to perform a controlled inlet mode transition. Prior to wind tunnel based hardware testing of controlled mode transitions, simulation models are used to test, debug, and validate potential control algorithms. One candidate simulation package for this purpose is the High Mach Transient Engine Cycle Code (HiTECC). The HiTECC simulation package models the inlet system, propulsion systems, thermal energy, geometry, nozzle, and fuel systems. This paper discusses the modification and redesign of the simulation package and control system to represent the NASA large-scale inlet model for Combined Cycle Engine mode transition studies, mounted in NASA Glenn s 10-foot by 10-foot Supersonic Wind Tunnel. This model will be used for designing and testing candidate control algorithms before implementation.

  15. A Turbine Based Combined Cycle Engine Inlet Model and Mode Transition Simulation Based on HiTECC Tool

    NASA Technical Reports Server (NTRS)

    Csank, Jeffrey T.; Stueber, Thomas J.

    2012-01-01

    An inlet system is being tested to evaluate methodologies for a turbine based combined cycle propulsion system to perform a controlled inlet mode transition. Prior to wind tunnel based hardware testing of controlled mode transitions, simulation models are used to test, debug, and validate potential control algorithms. One candidate simulation package for this purpose is the High Mach Transient Engine Cycle Code (HiTECC). The HiTECC simulation package models the inlet system, propulsion systems, thermal energy, geometry, nozzle, and fuel systems. This paper discusses the modification and redesign of the simulation package and control system to represent the NASA large-scale inlet model for Combined Cycle Engine mode transition studies, mounted in NASA Glenn s 10- by 10-Foot Supersonic Wind Tunnel. This model will be used for designing and testing candidate control algorithms before implementation.

  16. Integrated engine-generator for aircraft secondary power.

    NASA Technical Reports Server (NTRS)

    Secunde, R. R.

    1972-01-01

    The integrated engine-generator concept consists of an electric generator located inside a turbojet or turbofan engine and both concentric with and driven by one of the main engine shafts. The electric power-conversion equipment and generator controls are conveniently located in the aircraft. When properly rated, the generator serves as an engine starter as well as a source of electric power. The available generating capacity permits use of electrically driven engine accessories. This reduces or eliminates the need for an external gearbox on the engine, thereby simplifying the engine and nacelle assembly and increasing aircraft design flexibility. The nacelle diameter can then be decreased, resulting in less aerodynamic drag and reduced takeoff gross weight.

  17. 76 FR 82110 - Airworthiness Directives; Thielert Aircraft Engines GmbH Reciprocating Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-30

    ...-30-AD; Amendment 39-16906; AD 2010-06-12R1] RIN 2120-AA64 Airworthiness Directives; Thielert Aircraft.... SUMMARY: We are revising an existing airworthiness directive (AD) for Thielert Aircraft Engines GmbH models TAE 125-02-99 and TAE 125-01 reciprocating engines. That AD currently requires replacing...

  18. Further studies of methods for reducing community noise around airports. [aircraft noise - aircraft engines

    NASA Technical Reports Server (NTRS)

    Petersen, R. H.; Barry, D. J.; Kline, D. M.

    1975-01-01

    A simplified method of analysis was used in which all flights at a 'simulated' airport were assumed to operate from one runway in a single direction. For this simulated airport, contours of noise exposure forecast were obtained and evaluated. A flight schedule of the simulated airport which is representative of the 23 major U. S. airports was used. The effect of banning night-time operations by four-engine, narrow-body aircraft in combination with other noise reduction options was studied. The reductions in noise which would occur of two- and three-engine, narrow-body aircraft equipped with a refanned engine was examined. A detailed comparison of the effects of engine cutback on takeoff versus the effects of retrofitting quiet nacelles for narrow-body aircraft was also examined. A method of presenting the effects of various noise reduction options was treated.

  19. Lifecycle Information of Aircraft Engine Components

    DTIC Science & Technology

    2010-04-14

    commercial aircraft, the industry generated a number of potential RFID-based applications for airlines, air- freight carriers, aircraft maintenance and...adoption of RFID technologies to track serially controlled items requires careful planning and design. Data overload and data noise also affect the...performance of RFID systems. Data overload results from continuously scanning the RFID tags within reader range and sending the repeated information

  20. 77 FR 58301 - Technical Amendment; Airworthiness Standards: Aircraft Engines; Correction

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-20

    ... technical amendment, the FAA clarified aircraft engine vibration test requirements in the airworthiness... amendment, the FAA intended to clarify vibration test requirements in Sec. 33.83 of 14 Code of Federal... read as follows: Sec. 33.83 Vibration test. (a) Each engine must undergo vibration surveys to...

  1. Condensed data on the aircraft engines of the world

    NASA Technical Reports Server (NTRS)

    Fliedner, C S

    1929-01-01

    This compilation of the outstanding characteristics of the available aircraft engines of the world was prepared as a compact ready reference for desk use. It does not pretend to be anything but a skeleton outline of the characteristics of engines reported in the technical press as being in either the experimental, development, or production stage.

  2. Unsteady Reynolds-averaged Navier-Stokes simulations of inlet distortion in the fan system of a gas-turbine aero-engine

    NASA Astrophysics Data System (ADS)

    Spotts, Nathan

    As modern trends in commercial aircraft design move toward high-bypass-ratio fan systems of increasing diameter with shorter, nonaxisymmetric nacelle geometries, inlet distortion is becoming common in all operating regimes. The distortion may induce aerodynamic instabilities within the fan system, leading to catastrophic damage to fan blades, should the surge margin be exceeded. Even in the absence of system instability, the heterogeneity of the flow affects aerodynamic performance significantly. Therefore, an understanding of fan-distortion interaction is critical to aircraft engine system design. This thesis research elucidates the complex fluid dynamics and fan-distortion interaction by means of computational fluid dynamics (CFD) modeling of a complete engine fan system; including rotor, stator, spinner, nacelle and nozzle; under conditions typical of those encountered by commercial aircraft. The CFD simulations, based on a Reynolds-averaged Navier-Stokes (RANS) approach, were unsteady, three-dimensional, and of a full-annulus geometry. A thorough, systematic validation has been performed for configurations from a single passage of a rotor to a full-annulus system by comparing the predicted flow characteristics and aerodynamic performance to those found in literature. The original contributions of this research include the integration of a complete engine fan system, based on the NASA rotor 67 transonic stage and representative of the propulsion systems in commercial aircraft, and a benchmark case for unsteady RANS simulations of distorted flow in such a geometry under realistic operating conditions. This study is unique in that the complex flow dynamics, resulting from fan-distortion interaction, were illustrated in a practical geometry under realistic operating conditions. For example, the compressive stage is shown to influence upstream static pressure distributions and thus suppress separation of flow on the nacelle. Knowledge of such flow physics is

  3. Workshop on Aerosols and Particulates from Aircraft Gas Turbine Engines

    NASA Technical Reports Server (NTRS)

    Wey, Chown Chou (Compiler)

    1999-01-01

    In response to the National Research Council (NRC) recommendations, the Workshop on Aerosols and Particulates from Aircraft Gas Turbine Engines was organized by the NASA Lewis Research Center and held on July 29-30, 1997 at the Ohio Aerospace Institute in Cleveland, Ohio. The objective is to develop consensus among experts in the field of aerosols from gas turbine combustors and engines as to important issues and venues to be considered. Workshop participants' expertise included engine and aircraft design, combustion processes and kinetics, atmospheric science, fuels, and flight operations and instrumentation.

  4. Control Design for a Generic Commercial Aircraft Engine

    NASA Technical Reports Server (NTRS)

    Csank, Jeffrey; May, Ryan D.

    2010-01-01

    This paper describes the control algorithms and control design process for a generic commercial aircraft engine simulation of a 40,000 lb thrust class, two spool, high bypass ratio turbofan engine. The aircraft engine is a complex nonlinear system designed to operate over an extreme range of environmental conditions, at temperatures from approximately -60 to 120+ F, and at altitudes from below sea level to 40,000 ft, posing multiple control design constraints. The objective of this paper is to provide the reader an overview of the control design process, design considerations, and justifications as to why the particular architecture and limits have been chosen. The controller architecture contains a gain-scheduled Proportional Integral controller along with logic to protect the aircraft engine from exceeding any limits. Simulation results illustrate that the closed loop system meets the Federal Aviation Administration s thrust response requirements

  5. Improved Finite Element Modeling of the Turbofan Engine Inlet Radiation Problem

    NASA Technical Reports Server (NTRS)

    Roy, Indranil Danda; Eversman, Walter; Meyer, H. D.

    1993-01-01

    Improvements have been made in the finite element model of the acoustic radiated field from a turbofan engine inlet in the presence of a mean flow. The problem of acoustic radiation from a turbofan engine inlet is difficult to model numerically because of the large domain and high frequencies involved. A numerical model with conventional finite elements in the near field and wave envelope elements in the far field has been constructed. By employing an irrotational mean flow assumption, both the mean flow and the acoustic perturbation problem have been posed in an axisymmetric formulation in terms of the velocity potential; thereby minimizing computer storage and time requirements. The finite element mesh has been altered in search of an improved solution. The mean flow problem has been reformulated with new boundary conditions to make it theoretically rigorous. The sound source at the fan face has been modeled as a combination of positive and negative propagating duct eigenfunctions. Therefore, a finite element duct eigenvalue problem has been solved on the fan face and the resulting modal matrix has been used to implement a source boundary condition on the fan face in the acoustic radiation problem. In the post processing of the solution, the acoustic pressure has been evaluated at Gauss points inside the elements and the nodal pressure values have been interpolated from them. This has significantly improved the results. The effect of the geometric position of the transition circle between conventional finite elements and wave envelope elements has been studied and it has been found that the transition can be made nearer to the inlet than previously assumed.

  6. Noise simulation of aircraft engine fans by the boundary element method

    NASA Astrophysics Data System (ADS)

    Pyatunin, K. R.; Arkharova, N. V.; Remizov, A. E.

    2016-07-01

    Numerical simulation results of the civil aircraft engine fan stage noise in the far field are presented. Non-steady-state rotor-stator interaction is calculated the commercial software that solves the Navier-Stokes equations using differentturbulence models. Noise propagation to the far acoustic field is calculated by the boundary element method using acoustic Lighthill analogies without taking into account the mean current in the air inlet duct. The calculated sound pressure levels at points 50 m from the engine are presented, and the directional patterns of the acoustic radiation are shown. The use of the eddy resolving turbulence model to calculate rotor-stator interaction increases the accuracy in predicting fan stage noise.

  7. Exergo-Economic Analysis of an Experimental Aircraft Turboprop Engine Under Low Torque Condition

    NASA Astrophysics Data System (ADS)

    Atilgan, Ramazan; Turan, Onder; Aydin, Hakan

    Exergo-economic analysis is an unique combination of exergy analysis and cost analysis conducted at the component level. In exergo-economic analysis, cost of each exergy stream is determined. Inlet and outlet exergy streams of the each component are associated to a monetary cost. This is essential to detect cost-ineffective processes and identify technical options which could improve the cost effectiveness of the overall energy system. In this study, exergo-economic analysis is applied to an aircraft turboprop engine. Analysis is based on experimental values at low torque condition (240 N m). Main components of investigated turboprop engine are the compressor, the combustor, the gas generator turbine, the free power turbine and the exhaust. Cost balance equations have been formed for all components individually and exergo-economic parameters including cost rates and unit exergy costs have been calculated for each component.

  8. Aircraft anti-insect system

    NASA Technical Reports Server (NTRS)

    Spiro, Clifford Lawrence (Inventor); Fric, Thomas Frank (Inventor); Leon, Ross Michael (Inventor)

    1997-01-01

    Insect debris is removed from or prevented from adhering to insect impingement areas of an aircraft, particularly on an inlet cowl of an engine, by heating the area to 180.degree.-500.degree. C. An apparatus comprising a means to bring hot air from the aircraft engine to a plenum contiguous to the insect impingement area provides for the heating of the insect impingement areas to the required temperatures. The plenum can include at least one tube with a plurality of holes contained in a cavity within the inlet cowl. It can also include an envelope with a plurality of holes on its surface contained in a cavity within the inlet cowl.

  9. Aircraft stress sequence development: A complex engineering process made simple

    NASA Technical Reports Server (NTRS)

    Schrader, K. H.; Butts, D. G.; Sparks, W. A.

    1994-01-01

    Development of stress sequences for critical aircraft structure requires flight measured usage data, known aircraft loads, and established relationships between aircraft flight loads and structural stresses. Resulting cycle-by-cycle stress sequences can be directly usable for crack growth analysis and coupon spectra tests. Often, an expert in loads and spectra development manipulates the usage data into a typical sequence of representative flight conditions for which loads and stresses are calculated. For a fighter/trainer type aircraft, this effort is repeated many times for each of the fatigue critical locations (FCL) resulting in expenditure of numerous engineering hours. The Aircraft Stress Sequence Computer Program (ACSTRSEQ), developed by Southwest Research Institute under contract to San Antonio Air Logistics Center, presents a unique approach for making complex technical computations in a simple, easy to use method. The program is written in Microsoft Visual Basic for the Microsoft Windows environment.

  10. Rankline-Brayton engine powered solar thermal aircraft

    SciTech Connect

    Bennett, Charles L

    2012-03-13

    A solar thermal powered aircraft powered by heat energy from the sun. A Rankine-Brayton hybrid cycle heat engine is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller or other mechanism for enabling sustained free flight. The Rankine-Brayton engine has a thermal battery, preferably containing a lithium-hydride and lithium mixture, operably connected to it so that heat is supplied from the thermal battery to a working fluid. A solar concentrator, such as reflective parabolic trough, is movably connected to an optically transparent section of the aircraft body for receiving and concentrating solar energy from within the aircraft. Concentrated solar energy is collected by a heat collection and transport conduit, and heat transported to the thermal battery. A solar tracker includes a heliostat for determining optimal alignment with the sun, and a drive motor actuating the solar concentrator into optimal alignment with the sun based on a determination by the heliostat.

  11. Rankine-Brayton engine powered solar thermal aircraft

    SciTech Connect

    Bennett, Charles L.

    2009-12-29

    A solar thermal powered aircraft powered by heat energy from the sun. A Rankine-Brayton hybrid cycle heat engine is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller or other mechanism for enabling sustained free flight. The Rankine-Brayton engine has a thermal battery, preferably containing a lithium-hydride and lithium mixture, operably connected to it so that heat is supplied from the thermal battery to a working fluid. A solar concentrator, such as reflective parabolic trough, is movably connected to an optically transparent section of the aircraft body for receiving and concentrating solar energy from within the aircraft. Concentrated solar energy is collected by a heat collection and transport conduit, and heat transported to the thermal battery. A solar tracker includes a heliostat for determining optimal alignment with the sun, and a drive motor actuating the solar concentrator into optimal alignment with the sun based on a determination by the heliostat.

  12. Analytical Modeling of Herschel-Quincke Concept Applied to Inlet Turbofan Engines

    NASA Technical Reports Server (NTRS)

    Hallez, Raphael F.; Burdisso, Ricardo A.; Gerhold, Carl H. (Technical Monitor)

    2002-01-01

    This report summarizes the key results obtained by the Vibration and Acoustics Laboratories at Virginia Tech over the period from January 1999 to December 2000 on the project 'Investigation of an Adaptive Herschel-Quincke Tube Concept for the Reduction of Tonal and Broadband Noise from Turbofan Engines', funded by NASA Langley Research Center. The Herschel-Quincke (HQ) tube concept is a developing technique the consists of circumferential arrays of tubes around the duct. The analytical model is developed to provide prediction and design guidelines for application of the HQ concept to turbofan engine inlets. An infinite duct model is developed and used to provide insight into attenuation mechanisms and design strategies. Based on this early model, the NASA-developed TBIEM3D code is modified for the HQ system. This model allows for investigation of the HQ system combined with a passive liner.

  13. Surface cooling of scramjet engine inlets using heat pipe, transpiration, and film cooling

    SciTech Connect

    Modlin, J.M.; Colwell, G.T. Georgia Institute of Technology, Atlanta )

    1992-09-01

    This article reports the results of applying a finite-difference-based computational technique to the problem of predicting the transient thermal behavior of a scramjet engine inlet exposed to a typical hypersonic flight aerodynamic surface heating environment, including type IV shock interference heating. The leading-edge cooling model utilized incorporates liquid metal heat pipe cooling with surface transpiration and film cooling. Results include transient structural temperature distributions, aerodynamic heat inputs, and surface coolant distributions. It seems that these cooling techniques may be used to hold maximum skin temperatures to near acceptable values during the severe aerodynamic and type IV shock interference heating effects expected on the leading edge of a hypersonic aerospace vehicle scramjet engine. 15 refs.

  14. Conceptual design of single turbofan engine powered light aircraft

    NASA Technical Reports Server (NTRS)

    Snyder, F. S.; Voorhees, C. G.; Heinrich, A. M.; Baisden, D. N.

    1977-01-01

    The conceptual design of a four place single turbofan engine powered light aircraft was accomplished utilizing contemporary light aircraft conventional design techniques as a means of evaluating the NASA-Ames General Aviation Synthesis Program (GASP) as a preliminary design tool. In certain areas, disagreement or exclusion were found to exist between the results of the conventional design and GASP processes. Detail discussion of these points along with the associated contemporary design methodology are presented.

  15. Effects of Structural Flexibility on Aircraft-Engine Mounts

    NASA Technical Reports Server (NTRS)

    Phillips, W. H.

    1986-01-01

    Analysis extends technique for design of widely used type of vibration-isolating mounts for aircraft engines, in which rubber mounting pads located in plane behind center of gravity of enginepropeller combination. New analysis treats problem in statics. Results of simple approach useful in providing equations for design of vibrationisolating mounts. Equations applicable in usual situation in which engine-mount structure itself relatively light and placed between large mass of engine and other heavy components of airplane.

  16. Aircraft Turbine Engine Control Research at NASA Glenn Research Center

    NASA Technical Reports Server (NTRS)

    Garg, Sanjay

    2014-01-01

    This lecture will provide an overview of the aircraft turbine engine control research at NASA (National Aeronautics and Space Administration) Glenn Research Center (GRC). A brief introduction to the engine control problem is first provided with a description of the current state-of-the-art control law structure. A historical aspect of engine control development since the 1940s is then provided with a special emphasis on the contributions of GRC. The traditional engine control problem has been to provide a means to safely transition the engine from one steady-state operating point to another based on the pilot throttle inputs. With the increased emphasis on aircraft safety, enhanced performance and affordability, and the need to reduce the environmental impact of aircraft, there are many new challenges being faced by the designers of aircraft propulsion systems. The Controls and Dynamics Branch (CDB) at GRC is leading and participating in various projects in partnership with other organizations within GRC and across NASA, other government agencies, the U.S. aerospace industry, and academia to develop advanced propulsion controls and diagnostics technologies that will help meet the challenging goals of NASA programs under the Aeronautics Research Mission. The second part of the lecture provides an overview of the various CDB technology development activities in aircraft engine control and diagnostics, both current and some accomplished in the recent past. The motivation for each of the research efforts, the research approach, technical challenges and the key progress to date are summarized. The technologies to be discussed include system level engine control concepts, gas path diagnostics, active component control, and distributed engine control architecture. The lecture will end with a futuristic perspective of how the various current technology developments will lead to an Intelligent and Autonomous Propulsion System requiring none to very minimum pilot interface

  17. Multi-fuel rotary engine for general aviation aircraft

    NASA Technical Reports Server (NTRS)

    Jones, C.; Ellis, D. R.; Meng, P. R.

    1983-01-01

    Design studies of advanced multifuel general aviation and commuter aircraft rotary stratified charge engines are summarized. Conceptual design studies were performed at two levels of technology, on advanced general aviation engines sized to provide 186/250 shaft kW/hp under cruise conditions at 7620 (25000 m/ft) altitude. A follow on study extended the results to larger (2500 hp max.) engine sizes suitable for applications such as commuter transports and helicopters. The study engine designs were derived from relevant engine development background including both prior and recent engine test results using direct injected unthrottled rotary engine technology. Aircraft studies, using these resultant growth engines, define anticipated system effects of the performance and power density improvements for both single engine and twin engine airplanes. The calculated results indicate superior system performance and 27 to 33 percent fuel economy improvement for the rotary engine airplanes as compared to equivalent airframe concept designs with current baseline engines. The research and technology activities required to attain the projected engine performance levels are also discussed.

  18. A new modeling approach of pressure waves at the inlet of internal combustion engines

    NASA Astrophysics Data System (ADS)

    Chalet, David; Mahé, Alexandre; Hétet, Jean-François; Migaud, Jérôme

    2011-06-01

    This paper presents a new model used to describe the propagation of pressure waves at the inlet systems of internal combustion engine. In the first part, an analogy is made between the compressible air in a pipe and a mechanical ideal mass damper spring system. A new model is then presented and the parameters of this model are determined by the use of an experimental setup (shock tube test bench). With this model, a transfer function is defined in order to link directly the pressure and the air mass flow rate. In the second part, the model is included into an internal combustion engine simulation code. The results obtained with this code are compared to experimental ones which are measured on a one-cylinder engine test bench. This last one is driven by an electric motor in order to study only the effect of the pressure waves on the engine behavior. A good agreement is obtained between the experimental results and the numerical ones and the new approach is an alternative method for modeling the pressure wave phenomena in an internal combustion engine manifold.

  19. The Aerothermodynamics of Aircraft Gas Turbine Engines

    DTIC Science & Technology

    1978-07-01

    line and staggered tube ~ anks . Another way to get the coolant out of the trailing edge is to use drilled holes. These are normally calculated using...Pittsburgh, PA, 1976. 20.35 Butze, H. F., and Ehlers , R. C., "Effect of FUel Properties on Performance of a Single Aircraft Turbojet Combustor," NASA-Tl~-X...20.75 Butze, H. F .. and Ehlers , R. C., "Effect of Fuel Properties on Performance of A Single Aircraft Turboj et Combustor," NASA-TM-X-71789

  20. 77 FR 13488 - Airworthiness Directives; Thielert Aircraft Engines GmbH (TAE) Reciprocating Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-07

    ... Engines GmbH (TAE) Reciprocating Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final... TAE 125-02-99 reciprocating engines installed on, but not limited to, Diamond Aircraft Industries...-E002801, on TAE 125-02-99 engine. This AD was prompted by TAE increasing the life of the PPRV, part...

  1. 78 FR 1733 - Airworthiness Directives; Thielert Aircraft Engines GmbH Reciprocating Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-09

    ... Engines GmbH Reciprocating Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: We are superseding an existing airworthiness directive (AD) for all Thielert Aircraft Engines GmbH models TAE 125-01, TAE 125-02- 99, and TAE 125-02-114 reciprocating engines. That AD...

  2. 77 FR 4217 - Airworthiness Directives; Thielert Aircraft Engines GmbH Reciprocating Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-27

    ... Engines GmbH Reciprocating Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: We are adopting a new airworthiness directive (AD) for all Thielert Aircraft Engines GmbH (TAE) ] TAE 125-02-99 and TAE 125-02-114 reciprocating engines. This AD was prompted by in-flight...

  3. 78 FR 1728 - Airworthiness Directives; Thielert Aircraft Engines GmbH Reciprocating Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-09

    ... Engines GmbH Reciprocating Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: We are adopting a new airworthiness directive (AD) for all Thielert Aircraft Engines GmbH (TAE) TAE 125-02-99 and TAE 125-02-114 reciprocating engines. This AD requires inspection of the oil...

  4. Aircraft Turbine Engine Control Research at NASA Glenn Research Center

    NASA Technical Reports Server (NTRS)

    Garg, Sanjay

    2013-01-01

    This paper provides an overview of the aircraft turbine engine control research at the NASA Glenn Research Center (GRC). A brief introduction to the engine control problem is first provided with a description of the state-of-the-art control law structure. A historical aspect of engine control development since the 1940s is then provided with a special emphasis on the contributions of GRC. With the increased emphasis on aircraft safety, enhanced performance, and affordability, as well as the need to reduce the environmental impact of aircraft, there are many new challenges being faced by the designers of aircraft propulsion systems. The Controls and Dynamics Branch (CDB) at GRC is leading and participating in various projects to develop advanced propulsion controls and diagnostics technologies that will help meet the challenging goals of NASA Aeronautics Research Mission programs. The rest of the paper provides an overview of the various CDB technology development activities in aircraft engine control and diagnostics, both current and some accomplished in the recent past. The motivation for each of the research efforts, the research approach, technical challenges, and the key progress to date are summarized.

  5. Real-Time Aircraft Engine-Life Monitoring

    NASA Technical Reports Server (NTRS)

    Klein, Richard

    2014-01-01

    This project developed an inservice life-monitoring system capable of predicting the remaining component and system life of aircraft engines. The embedded system provides real-time, inflight monitoring of the engine's thrust, exhaust gas temperature, efficiency, and the speed and time of operation. Based upon this data, the life-estimation algorithm calculates the remaining life of the engine components and uses this data to predict the remaining life of the engine. The calculations are based on the statistical life distribution of the engine components and their relationship to load, speed, temperature, and time.

  6. Some aspects of aircraft jet engine fuels

    NASA Technical Reports Server (NTRS)

    Bekiesinski, R.

    1979-01-01

    Technologies are reviewed for improving the thermal stability of jet fuels, with reference to the overheating of fuel tanks in supersonic aircraft. Consideration is given to the development of a jet fuel with high thermal stability by the Polish petroleum industry.

  7. Combat aircraft jet engine noise studies

    NASA Astrophysics Data System (ADS)

    Lewy, S.; Fournier, G.; Pianko, M.

    Methods of noise prediction and attenuation, based on results obtained in civil applications are presented. Input data for directivity and radiation forecasts are given by measurements of vane and blade pressure fluctuations, and by modal analysis of the spinning waves propagating in the inlet duct. Attention is given to sound generation mechanisms for subsonic and supersonic single jets and bypass jets. Prediction methods, based on Lighthill's equation (tensor due to the turbulence), are discussed, and the various means of jet noise reduction are reviewed. The CEPRA 19 anechoic wind tunnel, which is primarily designed for studying the jet noise radiated in the far field with flight effects is described.

  8. Recent Progress in Engine Noise Reduction for Commercial Aircraft Applications

    NASA Technical Reports Server (NTRS)

    Huff, Dennis L.

    2003-01-01

    Considerable progress has been made over the past ten years developing technologies for reducing aircraft noise. Engine noise continues to be a dominate source, particularly for aircraft departing from airports. Research efforts have concentrated on developing noise prediction methods, experimental validation, and developing noise reduction concepts that have been verified through model scale and static engine tests. Most of the work has concentrated on fan and jet components for commercial turbofan engines. In this seminar, an overview of the engine noise reduction work that was sponsored by NASA s Advanced Subsonic Technology Noise Reduction Program will be given, along with background information on turbofan noise sources and certification procedures. Concepts like "chevron" nozzles for jet noise reduction and swept stators for fan noise reduction will be highlighted. A preliminary assessment on how the new technologies will impact future engines will be given.

  9. Characterization of chemical and particulate emissions from aircraft engines

    NASA Astrophysics Data System (ADS)

    Agrawal, Harshit; Sawant, Aniket A.; Jansen, Karel; Wayne Miller, J.; Cocker, David R.

    2008-06-01

    This paper presents a series of measurements from four on-wing, commercial aircraft engines, including two newer CFM56-7 engines and two earlier CFM56-3 engines. Samples were collected from each engine using a probe positioned behind the exhaust nozzle of the aircraft, chocked on a concrete testing pad. The emission factors for particulate matter mass, elemental and organic carbon, carbonyls, polycyclic aromatic hydrocarbons, n-alkanes, dioxins, metals and ions are reported for four different engine power setting modes. The emissions indices of particulate matter, elemental and organic carbon are highly power dependent for these engines. Particulate matter emission indices (g kg-1 fuel) are found to increase from 1.1E-02 to 2.05E-01 with increase in power from idle to 85%. The elemental carbon to organic carbon varies from 0.5 to 3.8 with change in power from idle to 85%. The carbonyl emissions are dominated by formaldehyde. The emission index of formaldehyde ranges from 2.3E-01 to 4.8E-01 g kg-1 fuel. The distribution of metals depends on the difference in the various engines. The dioxin emissions from the aircraft engines are observed to be below detection limit.

  10. Advanced control for airbreathing engines, volume 2: General Electric aircraft engines

    NASA Technical Reports Server (NTRS)

    Bansal, Indar

    1993-01-01

    The application of advanced control concepts to air breathing engines may yield significant improvements in aircraft/engine performance and operability. Screening studies of advanced control concepts for air breathing engines were conducted by three major domestic aircraft engine manufacturers to determine the potential impact of concepts on turbine engine performance and operability. The purpose of the studies was to identify concepts which offered high potential yet may incur high research and development risk. A target suite of proposed advanced control concepts was formulated and evaluated in a two phase study to quantify each concept's impact on desired engine characteristics. To aid in the evaluation specific aircraft/engine combinations were considered: a Military High Performance Fighter mission, a High Speed Civil Transport mission, and a Civil Tiltrotor mission. Each of the advanced control concepts considered in the study are defined and described. The concept potential impact on engine performance was determined. Relevant figures of merit on which to evaluate the concepts are determined. Finally, the concepts are ranked with respect to the target aircraft/engine missions. A final report describing the screening studies was prepared by each engine manufacturer. Volume 2 of these reports describes the studies performed by GE Aircraft Engines.

  11. Multi-Fuel Rotary Engine for General Aviation Aircraft

    NASA Technical Reports Server (NTRS)

    Jones, C.; Ellis, D. R.; Meng, P. R.

    1983-01-01

    Design studies, conducted for NASA, of Advanced Multi-fuel General Aviation and Commuter Aircraft Rotary Stratified Charge Engines are summarized. Conceptual design studies of an advanced engine sized to provide 186/250 shaft KW/HP under cruise conditions at 7620/25,000 m/ft. altitude were performed. Relevant engine development background covering both prior and recent engine test results of the direct injected unthrottled rotary engine technology, including the capability to interchangeably operate on gasoline, diesel fuel, kerosene, or aviation jet fuel, are presented and related to growth predictions. Aircraft studies, using these resultant growth engines, define anticipated system effects of the performance and power density improvements for both single engine and twin engine airplanes. The calculated results indicate superior system performance and 30 to 35% fuel economy improvement for the Rotary-engine airplanes as compared to equivalent airframe concept designs with current baseline engines. The research and technology activities required to attain the projected engine performance levels are also discussed.

  12. Organic positive ions in aircraft gas-turbine engine exhaust

    NASA Astrophysics Data System (ADS)

    Sorokin, Andrey; Arnold, Frank

    Volatile organic compounds (VOCs) represent a significant fraction of atmospheric aerosol. However the role of organic species emitted by aircraft (as a consequence of the incomplete combustion of fuel in the engine) in nucleation of new volatile particles still remains rather speculative and requires a much more detailed analysis of the underlying mechanisms. Measurements in aircraft exhaust plumes have shown the presence of both different non-methane VOCs (e.g. PartEmis project) and numerous organic cluster ions (MPIK-Heidelberg). However the link between detected organic gas-phase species and measured mass spectrum of cluster ions is uncertain. Unfortunately, up to now there are no models describing the thermodynamics of the formation of primary organic cluster ions in the exhaust of aircraft engines. The aim of this work is to present first results of such a model development. The model includes the block of thermodynamic data based on proton affinities and gas basicities of organic molecules and the block of non-equilibrium kinetics of the cluster ions evolution in the exhaust. The model predicts important features of the measured spectrum of positive ions in the exhaust behind aircraft. It is shown that positive ions emitted by aircraft engines into the atmosphere mostly consist of protonated and hydrated organic cluster ions. The developed model may be explored also in aerosol investigations of the background atmosphere as well as in the analysis of the emission of fine aerosol particles by automobiles.

  13. Water Misting and Injection of Commercial Aircraft Engines to Reduce Airport NOx

    NASA Technical Reports Server (NTRS)

    Daggett, David L.; Hendricks, Robert C. (Technical Monitor)

    2004-01-01

    This report provides the first high level look at system design, airplane performance, maintenance, and cost implications of using water misting and water injection technology in aircraft engines for takeoff and climb-out NOx emissions reduction. With an engine compressor inlet water misting rate of 2.2 percent water-to-air ratio, a 47 percent NOx reduction was calculated. Combustor water injection could achieve greater reductions of about 85 percent, but with some performance penalties. For the water misting system on days above 59 F, a fuel efficiency benefit of about 3.5 percent would be experienced. Reductions of up to 436 F in turbine inlet temperature were also estimated, which could lead to increased hot section life. A 0.61 db noise reduction will occur. A nominal airplane weight penalty of less than 360 lb (no water) was estimated for a 305 passenger airplane. The airplane system cost is initially estimated at $40.92 per takeoff giving an attractive NOx emissions reduction cost/benefit ratio of about $1,663/ton.

  14. F-15 inlet/engine test techniques and distortion methodologies studies. Volume 1: Technical discussion

    NASA Technical Reports Server (NTRS)

    Stevens, C. H.; Spong, E. D.; Hammock, M. S.

    1978-01-01

    Peak distortion data taken from a subscale inlet model were studied to determine if the data can be used to predict peak distortion levels for a full scale flight test vehicle, and to provide a better understanding of the time variant total pressure distortion and the attendant effects of Reynolds number/scale and frequency content. The data base used to accomplish this goal covered a range from Mach 0.4 to 2.5 and an angle of attack range from -10 degrees to +12 degrees. Data are presented which show that: (1) increasing the Reynolds number increases total pressure recovery, decreases peak distortion, and decreases turbulence, (2) increasing the filter cutoff frequency increases both peak distortion and turbulence, and (3) the effect of engine presence on total pressure recovery, peak distortion, and turbulence is small but favorable.

  15. Analytical investigation of adaptive control of radiated inlet noise from turbofan engines

    NASA Technical Reports Server (NTRS)

    Risi, John D.; Burdisso, Ricardo A.

    1994-01-01

    An analytical model has been developed to predict the resulting far field radiation from a turbofan engine inlet. A feedforward control algorithm was simulated to predict the controlled far field radiation from the destructive combination of fan noise and secondary control sources. Numerical results were developed for two system configurations, with the resulting controlled far field radiation patterns showing varying degrees of attenuation and spillover. With one axial station of twelve control sources and error sensors with equal relative angular positions, nearly global attenuation is achieved. Shifting the angular position of one error sensor resulted in an increase of spillover to the extreme sidelines. The complex control inputs for each configuration was investigated to identify the structure of the wave pattern created by the control sources, giving an indication of performance of the system configuration. It is deduced that the locations of the error sensors and the control source configuration are equally critical to the operation of the active noise control system.

  16. A Systems Engineering Approach to Aircraft Kinetic Kill Countermeasures Technology: Development of an Active Aircraft Defense System for the C/KC-135 Aircraft. Volume 1

    DTIC Science & Technology

    1995-12-01

    AFIT/GSE/ENY/95D-01 A SYSTEMS ENGINEERING APPROACH TO AIRCRAFT KINETIC KILL COUNTERMEASURE TECHNOLOGY: DEVELOPMENT OF AN ACTIVE AIR DEFENSE SYSTEM...AFIT/GSE/ENY/95D-01 A SYSTEMS ENGINEERING APPROACH TO AIRCRAFT KINETIC KILL COUNTERMEASURE TECHNOLOGY: DEVELOPMENT OF AN ACTIVE AIR DEFENSE SYSTEM FOR...THE C/KC-135 AIRCRAFT THESIS (1 of2) Presented to the Faculty of the Graduate School of Engineering of the Air Force Institute of Technology Air

  17. Review of the Rhein-Flugzeugbau Wankel powered aircraft program. [ducted fan engines

    NASA Technical Reports Server (NTRS)

    Riethmueller, M.

    1978-01-01

    The development of light aircraft with special emphasis on modern propulsion systems and production is discussed in terms of the application of rotary engines to aircraft. Emphasis is placed on the integrated ducted-fan propulsion system using rotary engines.

  18. Active Control of Inlet Noise on the JT15D Turbofan Engine

    NASA Technical Reports Server (NTRS)

    Smith, Jerome P.; Hutcheson, Florence V.; Burdisso, Ricardo A.; Fuller, Chris R.

    1999-01-01

    This report presents the key results obtained by the Vibration and Acoustics Laboratories at Virginia Tech over the year from November 1997 to December 1998 on the Active Noise Control of Turbofan Engines research project funded by NASA Langley Research Center. The concept of implementing active noise control techniques with fuselage-mounted error sensors is investigated both analytically and experimentally. The analytical part of the project involves the continued development of an advanced modeling technique to provide prediction and design guidelines for application of active noise control techniques to large, realistic high bypass engines of the type on which active control methods are expected to be applied. Results from the advanced analytical model are presented that show the effectiveness of the control strategies, and the analytical results presented for fuselage error sensors show good agreement with the experimentally observed results and provide additional insight into the control phenomena. Additional analytical results are presented for active noise control used in conjunction with a wavenumber sensing technique. The experimental work is carried out on a running JT15D turbofan jet engine in a test stand at Virginia Tech. The control strategy used in these tests was the feedforward Filtered-X LMS algorithm. The control inputs were supplied by single and multiple circumferential arrays of acoustic sources equipped with neodymium iron cobalt magnets mounted upstream of the fan. The reference signal was obtained from an inlet mounted eddy current probe. The error signals were obtained from a number of pressure transducers flush-mounted in a simulated fuselage section mounted in the engine test cell. The active control methods are investigated when implemented with the control sources embedded within the acoustically absorptive material on a passively-lined inlet. The experimental results show that the combination of active control techniques with fuselage

  19. 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%.

  20. NO(x) reduction additives for aircraft gas turbine engines

    NASA Technical Reports Server (NTRS)

    Adelman, Henry G.; Menees, Gene P.; Cambier, Jean-Luc

    1993-01-01

    The reduction of oxides of nitrogen (NO(x)) emissions from aircraft gas turbine engines is a vital part of the NASA High Speed Research Program. Emissions reductions are critical to the feasibility of future High Speed Civil Transports which operate at supersonic speeds in the stratosphere. It is believed that large fleets of such aircraft using conventional gas turbine engines would emit levels of NO(x) that would be harmful to the stratospheric ozone layer. Previous studies have shown that NO(x) emissions can be reduced from stationary powerplant exhausts by the addition of additives such as ammonia to the exhaust gases. Since the exhaust residence times, pressures and temperatures may be different for aircraft gas turbines, a study has been made of additive effectiveness for high speed, high altitude flight.

  1. Energy efficient engine flight propulsion system: Aircraft/engine integration evaluation

    NASA Technical Reports Server (NTRS)

    Patt, R. F.

    1980-01-01

    Results of aircraft/engine integration studies conducted on an advanced flight propulsion system are reported. Economic evaluations of the preliminary design are included and indicate that program goals will be met. Installed sfc, DOC, noise, and emissions were evaluated. Aircraft installation considerations and growth were reviewed.

  2. Energy efficient engine flight propulsion system: Aircraft/engine integration evaluation

    SciTech Connect

    Patt, R.F.

    1980-06-01

    Results of aircraft/engine integration studies conducted on an advanced flight propulsion system are reported. Economic evaluations of the preliminary design are included and indicate that program goals will be met. Installed sfc, DOC, noise, and emissions were evaluated. Aircraft installation considerations and growth were reviewed.

  3. Buzz-saw noise : propagation of shock waves in aero-engine inlet ducts

    NASA Astrophysics Data System (ADS)

    Fernando, Rasika; Marchiano, Régis; Coulouvrat, François; Druon, Yann

    2008-06-01

    For supersonic flows relative to turbo-engine fan blades, measured acoustic spectra near the inlet present tones at fan blade passing frequency (BPF), engine shaft rotation frequency, or Engine Order (EO), and their respective harmonics. The latter are responsible for the Buzz-saw noise and are thus referred to as "Buzz-saw" or "multiple pure" tones. This work first attempts to reformulate McAlpine and Fisher's frequency domain model (2001) for the propagation of a unidimensional sawtooth waveform spiralling inside a hard-walled cylindrical duct in the presence of a uniform flow. The non-dissipative Burgers equation is solved using a shock fitting method, and modal attenuation and dispersion are added using a split-step computational method. In practice, shocks do not only occur at blade tips but on a significant portion of the blade span. The plane wave hypothesis being no longer valid, a new three dimensional model is required. This model is based on the computation of the axially varying amplitudes of the modal solutions, in order to take into account the nonlinear modal interactions.

  4. Calculation of the pressures on aircraft engine bearings

    NASA Technical Reports Server (NTRS)

    Steigenberger, O

    1929-01-01

    For aircraft engines the three principal operating conditions are idling speed, cruising speed, and diving with the engine stopped. In what follows, we will discuss a method which affords a good idea of the course of pressure for the above mentioned operating conditions. The pressures produced in the driving gear are of three kinds; namely, the pressure due to gases, the pressure due to the inertia of the rotating masses, and the pressure due to the inertia of the reciprocating masses.

  5. Combustion system CFD modeling at GE Aircraft Engines

    NASA Technical Reports Server (NTRS)

    Burrus, D.; Mongia, H.; Tolpadi, Anil K.; Correa, S.; Braaten, M.

    1995-01-01

    This viewgraph presentation discusses key features of current combustion system CFD modeling capabilities at GE Aircraft Engines provided by the CONCERT code; CONCERT development history; modeling applied for designing engine combustion systems; modeling applied to improve fundamental understanding; CONCERT3D results for current production combustors; CONCERT3D model of NASA/GE E3 combustor; HYBRID CONCERT CFD/Monte-Carlo modeling approach; and future modeling directions.

  6. Optimal Discrete Event Supervisory Control of Aircraft Gas Turbine Engines

    NASA Technical Reports Server (NTRS)

    Litt, Jonathan (Technical Monitor); Ray, Asok

    2004-01-01

    This report presents an application of the recently developed theory of optimal Discrete Event Supervisory (DES) control that is based on a signed real measure of regular languages. The DES control techniques are validated on an aircraft gas turbine engine simulation test bed. The test bed is implemented on a networked computer system in which two computers operate in the client-server mode. Several DES controllers have been tested for engine performance and reliability.

  7. Exhaust emissions reduction for intermittent combustion aircraft engines

    NASA Technical Reports Server (NTRS)

    Rezy, B. J.; Stuckas, K. J.; Tucker, J. R.; Meyers, J. E.

    1982-01-01

    Three concepts which, to an aircraft piston engine, provide reductions in exhaust emissions of hydrocarbons and carbon monoxide while simultaneously improving fuel economy. The three chosen concepts, (1) an improved fuel injection system, (2) an improved cooling cylinder head, and (3) exhaust air injection, when combined, show a synergistic relationship in achieving these goals. In addition, the benefits of variable ignition timing were explored and both dynamometer and flight testing of the final engine configuration were accomplished.

  8. Energy efficient engine: Propulsion system-aircraft integration evaluation

    NASA Technical Reports Server (NTRS)

    Owens, R. E.

    1979-01-01

    Flight performance and operating economics of future commercial transports utilizing the energy efficient engine were assessed as well as the probability of meeting NASA's goals for TSFC, DOC, noise, and emissions. Results of the initial propulsion systems aircraft integration evaluation presented include estimates of engine performance, predictions of fuel burns, operating costs of the flight propulsion system installed in seven selected advanced study commercial transports, estimates of noise and emissions, considerations of thrust growth, and the achievement-probability analysis.

  9. Advanced materials research for long-haul aircraft turbine engines

    NASA Technical Reports Server (NTRS)

    Signorelli, R. A.; Blankenship, C. P.

    1978-01-01

    The status of research efforts to apply low to intermediate temperature composite materials and advanced high temperature materials to engine components is reviewed. Emerging materials technologies and their potential benefits to aircraft gas turbines were emphasized. The problems were identified, and the general state of the technology for near term use was assessed.

  10. Computational study of inlet injection for a Pre-Mixed, Shock-Induced Combustion (PM/SIC) engine

    NASA Technical Reports Server (NTRS)

    Gonzalez, D. E.

    1995-01-01

    A computational simulation of reacting 2-D and 3-D flowfields in a model inlet section of a Pre-Mixed, Shock-Induced Combustion (PM/SIC) engine concept was performed. LARCK, a multi-dimensional Navier-Stokes code with finite-rate kinetics chemistry developed at NASA LaRC by J.A. White, was adapted for this simulation. The flow conditions in the simulation match those envisioned for the PM/SIC engine experiments currently planned at LaRC. The reacting flowfields were Mach 6.3 freestream air and Mach 2 hydrogen at various pressure and temperature conditions injected through a slot injector at the base of the inlet section. In the PM/SIC engine, fuel is injected at the inlet section upstream of the combustor, and reaction is initiated by the shock wave at the inlet which increases the gas temperature and pressure beyond the kinetic limits for reaction. Many challenges exist prior to establishing shock-controlled combustion as a practical engine concept. These challenges include fuel injection schemes that can provide proper fuel-air mixing without creating large losses in the inlet section, and control of the combustion process so that early ignition or combustion propagation through the inlet boundary layer does not occur. For this project, a parametrics study was carried out to model the fuel injection of hydrogen at different flow conditions. It was found that, as the fuel temperature and pressure were increased, the potential for pre-ignition was high at a short distance downstream of the slot injector. The next stage of this work will investigate injection techniques for enhancing mixing of fuel and air in a manner that prevents or reduces the potential for premature ignition observed numerically.

  11. The Power of Aircraft Engines at Altitude

    NASA Technical Reports Server (NTRS)

    Ragazzi, Paolo

    1939-01-01

    The subject of the present paper is confined to the investigations and methods employed by the Fiat company in their studies on the altitude performance of an air-cooled engine of the production type. The experimental set-up as well as test engine data are provided.

  12. 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.

  13. Swirling-flow jet noise suppressors for aircraft engines

    NASA Technical Reports Server (NTRS)

    Schwartz, I. R.

    1976-01-01

    Experimental investigations of the effects of swirling the jet exhausts of small turbofan and turbojet engines have indicated significant progress towards predicting and attaining substantial jet noise abatement with minimum thrust losses in large aircraft engines. Systematic variations of the important swirl vane and swirling flow parameters were conducted to determine their effects on jet noise reduction and engine performance. Since swirling flow becomes more effective in reducing jet noise as the density and temperature gradients increase, the significant trends in noise reduction and engine performance that were established by these parametric studies could be projected into potentially greater reductions of sound pressure levels with minimum thrust losses by controlled swirling of the jets of high thrust engines. The density and temperature gradients in the jet exhausts of high thrust engines are larger by comparison with gradients in small engines.

  14. Stratified charge rotary aircraft engine technology enablement program

    NASA Technical Reports Server (NTRS)

    Badgley, P. R.; Irion, C. E.; Myers, D. M.

    1985-01-01

    The multifuel stratified charge rotary engine is discussed. A single rotor, 0.7L/40 cu in displacement, research rig engine was tested. The research rig engine was designed for operation at high speeds and pressures, combustion chamber peak pressure providing margin for speed and load excursions above the design requirement for a high is advanced aircraft engine. It is indicated that the single rotor research rig engine is capable of meeting the established design requirements of 120 kW, 8,000 RPM, 1,379 KPA BMEP. The research rig engine, when fully developed, will be a valuable tool for investigating, advanced and highly advanced technology components, and provide an understanding of the stratified charge rotary engine combustion process.

  15. Study of advanced rotary combustion engines for commuter aircraft

    NASA Technical Reports Server (NTRS)

    Berkowitz, M.; Jones, C.; Myers, D.

    1983-01-01

    Performance, weight, size, and maintenance data for advanced rotary aircraft engines suitable for comparative commuter aircraft system evaluation studies of alternate engine candidates are provided. These are turbocharged, turbocompounded, direct injected, stratified charge rotary engines. Hypothetical engines were defined (an RC4-74 at 895 kW and an RC6-87 at 1490 kW) based on the technologies and design approaches used in the highly advanced engine of a study of advanced general aviation rotary engines. The data covers the size range of shaft power from 597 kW (800 hp) to 1865 kW (2500 hp) and is in the form of drawings, tables, curves and written text. These include data on internal geometry and configuration, installation information, turbocharging and turbocompounding arrangements, design features and technologies, engine cooling, fuels, scaling for weight size BSFC and heat rejection for varying horsepower, engine operating and performance data, and TBO and maintenance requirements. The basic combustion system was developed and demonstrated; however the projected power densities and performance efficiencies require increases in engine internal pressures, thermal loading, and rotative speed.

  16. A 150 and 300 kW lightweight diesel aircraft engine design study

    NASA Technical Reports Server (NTRS)

    Brouwers, A. P.

    1980-01-01

    The diesel engine was reinvestigated as an aircraft powerplant through design study conducted to arrive at engine configurations and applicable advanced technologies. Two engines are discussed, a 300 kW six-cylinder engine for twin engine general aviation aircraft and a 150 kW four-cylinder engine for single engine aircraft. Descriptions of each engine include concept drawings, a performance analysis, stress and weight data, and a cost study. This information was used to develop two airplane concepts, a six-place twin and a four-place single engine aircraft. The aircraft study consists of installation drawings, computer generated performance data, aircraft operating costs, and drawings of the resulting airplanes. The performance data show a vast improvement over current gasoline-powered aircraft.

  17. Aircraft Turbine Engine Reliability and Inspection Investigations

    DTIC Science & Technology

    1993-10-01

    controls and accessories typically produced the largest number of in-flight flameouts, compressor stalls , and engine shutdowns. In addition to the actuarial...typically produced the largest number of in-flight flameouts, compressor stalls , and engine shutdowns. Diagnostic troubleshooting procedures for controls...airfoils suffer because these * materials are damaged during compressor stalls when cooling air flows are disrupted. 3. Fuel/oil system failures are

  18. Cabin Noise Control for Twin Engine General Aviation Aircraft

    NASA Technical Reports Server (NTRS)

    Vaicaitis, R.; Slazak, M.

    1982-01-01

    An analytical model based on modal analysis was developed to predict the noise transmission into a twin-engine light aircraft. The model was applied to optimize the interior noise to an A-weighted level of 85 dBA. To achieve the required noise attenuation, add-on treatments in the form of honeycomb panels, damping tapes, acoustic blankets, septum barriers and limp trim panels were added to the existing structure. The added weight of the noise control treatment is about 1.1 percent of the total gross take-off weight of the aircraft.

  19. Toward improved durability in advanced aircraft engine hot sections

    NASA Technical Reports Server (NTRS)

    Sokolowski, Daniel E. (Editor)

    1989-01-01

    The conference on durability improvement methods for advanced aircraft gas turbine hot-section components discussed NASA's Hot Section Technology (HOST) project, advanced high-temperature instrumentation for hot-section research, the development and application of combustor aerothermal models, and the evaluation of a data base and numerical model for turbine heat transfer. Also discussed are structural analysis methods for gas turbine hot section components, fatigue life-prediction modeling for turbine hot section materials, and the service life modeling of thermal barrier coatings for aircraft gas turbine engines.

  20. The comparative performance of an aviation engine at normal and high inlet air temperatures

    NASA Technical Reports Server (NTRS)

    Gardiner, Arthur W; Schey, Oscar W

    1928-01-01

    This report presents some results obtained during an investigation to determine the effect of high inlet air temperature on the performance of a Liberty 12 aviation engine. The purpose of this investigation was to ascertain, for normal service carburetor adjustments and a fixed ignition advance, the relation between power and temperature for the range of carburetor air temperatures that may be encountered when supercharging to sea level pressure at altitudes of over 20,000 feet and without intercooling when using plain aviation gasoline and mixtures of benzol and gasoline. The results show that for the conditions of test, both the brake and indicated power decrease with increase in air temperature at a faster rate than given by the theoretical assumption that power varies inversely as the square root of the absolute temperature. On a brake basis, the order of the difference in power for a temperature difference of 120 degrees F. Is 3 to 5 per cent. The observed relation between power and temperature when using the 30-70 blend was found to be linear. But, although these differences are noted, the above theoretical assumption may be considered as generally applicable except where greater precision over a wide range of temperatures is desired, in which case it appears necessary to test the particular engine under the given conditions. (author)

  1. Characterization of lubrication oil emissions from aircraft engines.

    PubMed

    Yu, Zhenhong; Liscinsky, David S; Winstead, Edward L; True, Bruce S; Timko, Michael T; Bhargava, Anuj; Herndon, Scott C; Miake-Lye, Richard C; Anderson, Bruce E

    2010-12-15

    In this first ever study, particulate matter (PM) emitted from the lubrication system overboard breather vent for two different models of aircraft engines has been systematically characterized. Lubrication oil was confirmed as the predominant component of the emitted particulate matter based upon the characteristic mass spectrum of the pure oil. Total particulate mass and size distributions of the emitted oil are also investigated by several high-sensitivity aerosol characterization instruments. The emission index (EI) of lubrication oil at engine idle is in the range of 2-12 mg kg(-1) and increases with engine power. The chemical composition of the oil droplets is essentially independent of engine thrust, suggesting that engine oil does not undergo thermally driven chemical transformations during the ∼4 h test window. Volumetric mean diameter is around 250-350 nm for all engine power conditions with a slight power dependence.

  2. Aircraft

    DOEpatents

    Hibbs, B.D.; Lissaman, P.B.S.; Morgan, W.R.; Radkey, R.L.

    1998-09-22

    This disclosure provides a solar rechargeable aircraft that is inexpensive to produce, is steerable, and can remain airborne almost indefinitely. The preferred aircraft is a span-loaded flying wing, having no fuselage or rudder. Travelling at relatively slow speeds, and having a two-hundred foot wingspan that mounts photovoltaic cells on most all of the wing`s top surface, the aircraft uses only differential thrust of its eight propellers to turn. Each of five sections of the wing has one or more engines and photovoltaic arrays, and produces its own lift independent of the other sections, to avoid loading them. Five two-sided photovoltaic arrays, in all, are mounted on the wing, and receive photovoltaic energy both incident on top of the wing, and which is incident also from below, through a bottom, transparent surface. The aircraft is capable of a top speed of about ninety miles per hour, which enables the aircraft to attain and can continuously maintain altitudes of up to sixty-five thousand feet. Regenerative fuel cells in the wing store excess electricity for use at night, such that the aircraft can sustain its elevation indefinitely. A main spar of the wing doubles as a pressure vessel that houses hydrogen and oxygen gases for use in the regenerative fuel cell. The aircraft has a wide variety of applications, which include weather monitoring and atmospheric testing, communications, surveillance, and other applications as well. 31 figs.

  3. Aircraft

    DOEpatents

    Hibbs, Bart D.; Lissaman, Peter B. S.; Morgan, Walter R.; Radkey, Robert L.

    1998-01-01

    This disclosure provides a solar rechargeable aircraft that is inexpensive to produce, is steerable, and can remain airborne almost indefinitely. The preferred aircraft is a span-loaded flying wing, having no fuselage or rudder. Travelling at relatively slow speeds, and having a two-hundred foot wingspan that mounts photovoltaic cells on most all of the wing's top surface, the aircraft uses only differential thrust of its eight propellers to turn. Each of five sections of the wing has one or more engines and photovoltaic arrays, and produces its own lift independent of the other sections, to avoid loading them. Five two-sided photovoltaic arrays, in all, are mounted on the wing, and receive photovoltaic energy both incident on top of the wing, and which is incident also from below, through a bottom, transparent surface. The aircraft is capable of a top speed of about ninety miles per hour, which enables the aircraft to attain and can continuously maintain altitudes of up to sixty-five thousand feet. Regenerative fuel cells in the wing store excess electricity for use at night, such that the aircraft can sustain its elevation indefinitely. A main spar of the wing doubles as a pressure vessel that houses hydrogen and oxygen gasses for use in the regenerative fuel cell. The aircraft has a wide variety of applications, which include weather monitoring and atmospheric testing, communications, surveillance, and other applications as well.

  4. Liquid lubricants for advanced aircraft engines

    NASA Technical Reports Server (NTRS)

    Loomis, William R.; Fusaro, Robert L.

    1992-01-01

    An overview of liquid lubricants for use in current and projected high performance turbojet engines is discussed. Chemical and physical properties are reviewed with special emphasis placed on the oxidation and thermal stability requirements imposed upon the lubrication system. A brief history is given of the development of turbine engine lubricants which led to the present day synthetic oils with their inherent modification advantages. The status and state of development of some eleven candidate classes of fluids for use in advanced turbine engines are discussed. Published examples of fundamental studies to obtain a better understanding of the chemistry involved in fluid degradation are reviewed. Alternatives to high temperature fluid development are described. The importance of continuing work on improving current high temperature lubricant candidates and encouraging development of new and improved fluid base stocks are discussed.

  5. Liquid lubricants for advanced aircraft engines

    SciTech Connect

    Loomis, W.R.; Fusaro, R.L.

    1992-08-01

    An overview of liquid lubricants for use in current and projected high performance turbojet engines is discussed. Chemical and physical properties are reviewed with special emphasis placed on the oxidation and thermal stability requirements imposed upon the lubrication system. A brief history is given of the development of turbine engine lubricants which led to the present day synthetic oils with their inherent modification advantages. The status and state of development of some eleven candidate classes of fluids for use in advanced turbine engines are discussed. Published examples of fundamental studies to obtain a better understanding of the chemistry involved in fluid degradation are reviewed. Alternatives to high temperature fluid development are described. The importance of continuing work on improving current high temperature lubricant candidates and encouraging development of new and improved fluid base stocks are discussed.

  6. Liquid lubricants for advanced aircraft engines

    NASA Technical Reports Server (NTRS)

    Loomis, William R.; Fusaro, Robert L.

    1993-01-01

    An overview of liquid lubricants for use in current and projected high performance turbojet engines is discussed. Chemical and physical properties are reviewed with special emphasis placed on the oxidation and thermal stability requirements imposed upon the lubrication system. A brief history is given of the development of turbine engine lubricants which led to the present day synthetic oils with their inherent modification advantages. The status and state of development of some eleven candidate classes of fluids for use in advanced turbine engines are discussed. Published examples of fundamental studies to obtain a better understanding of the chemistry involved in fluid degradation are reviewed. Alternatives to high temperature fluid development are described. The importance of continuing work on improving current high temperature lubricant candidates and encouraging development of new and improved fluid base stocks are discussed.

  7. Two-Dimensional Bifurcated Inlet/Engine Tests Completed in 10- by 10-Foot Supersonic Wind Tunnel

    NASA Technical Reports Server (NTRS)

    Saunders, John D.

    1999-01-01

    A Two-Dimensional Bifurcated (2DB) Inlet was successfully tested in NASA Lewis Research Center s 10- by 10-Foot Supersonic Wind Tunnel. These tests were the culmination of a collaborative effort between the Boeing Company, General Electric, Pratt & Whitney, and Lewis. Extensive support in-house at Lewis contributed significantly to the progress and accomplishment of this test. The results, which met or exceeded many of the High-Speed Research (HSR) Program goals, were used to revise system studies within the HSR Program. The HSR Program is focused on developing low-noise, low-polluting, high-efficiency supersonic commercial aircraft. A supersonic inlet is an important component of an efficient, low-noise vehicle.

  8. Test data report, low speed wind tunnel tests of a full scale lift/cruise-fan inlet, with engine, at high angles of attack

    NASA Technical Reports Server (NTRS)

    Shain, W. M.

    1978-01-01

    A low speed wind tunnel test of a fixed lip inlet with engine, was performed. The inlet was close coupled to a Hamilton Standard 1.4 meter, variable pitch fan driven by a lycoming T55-L-11A engine. Tests were conducted with various combinations of inlet angle of attack freestream velocities, and fan airflows. Data were recorded to define the inlet airflow separation boundaries, performance characteristics, and fan blade stresses. The test model, installation, instrumentation, test, data reduction and final data are described.

  9. Effectiveness of combined aircraft engine noise suppressors

    NASA Astrophysics Data System (ADS)

    Khaletskiy, Yu. D.

    2012-07-01

    We consider the design features of fan noise suppressors in application to air intakes and the bypass duct of a turbofan engine. A combined liner is developed that has increased acoustic efficiency in comparison to conventional honeycomb liner. We demonstrate the important role of the area of the sound-absorbing liner between fan Rotor and Stator ensuring significant noise reduction.

  10. Engine Conceptual Design Studies for a Hybrid Wing Body Aircraft

    NASA Technical Reports Server (NTRS)

    Tong, Michael T.; Jones, Scott M.; Haller, William J.; Handschuh, Robert F.

    2009-01-01

    Worldwide concerns of air quality and climate change have made environmental protection one of the most critical issues in aviation today. NASA's current Fundamental Aeronautics research program is directed at three generations of aircraft in the near, mid and far term, with initial operating capability around 2015, 2020, and 2030, respectively. Each generation has associated goals for fuel burn, NOx, noise, and field-length reductions relative to today's aircrafts. The research for the 2020 generation is directed at enabling a hybrid wing body (HWB) aircraft to meet NASA's aggressive technology goals. This paper presents the conceptual cycle and mechanical designs of the two engine concepts, podded and embedded systems, which were proposed for a HWB cargo freighter. They are expected to offer significant benefits in noise reductions without compromising the fuel burn.

  11. NASA Glenn's Contributions to Aircraft Engine Noise Research

    NASA Technical Reports Server (NTRS)

    Huff, Dennis L.

    2013-01-01

    This report reviews all engine noise research conducted at the NASA Glenn Research Center over the past 70 years. This report includes a historical perspective of the Center and the facilities used to conduct the research. Major noise research programs are highlighted to show their impact on industry and on the development of aircraft noise reduction technology. Noise reduction trends are discussed, and future aircraft concepts are presented. Since the 1960s, research results show that the average perceived noise level has been reduced by about 20 decibels (dB). Studies also show that, depending on the size of the airport, the aircraft fleet mix, and the actual growth in air travel, another 15 to 17 dB reduction will be required to achieve NASA's long-term goal of providing technologies to limit objectionable noise to the boundaries of an average airport.

  12. NASA Glenn's Contributions to Aircraft Engine Noise Research

    NASA Technical Reports Server (NTRS)

    Huff, Dennis L.

    2014-01-01

    This presentation reviews engine noise research conducted at the NASA Glenn Research Center over the past 70 years. This report includes a historical perspective of the Center and the facilities used to conduct the research. Major noise research programs are highlighted to show their impact on industry and on the development of aircraft noise reduction technology. Noise reduction trends are discussed, and future aircraft concepts are presented. Since the 1960s, research results show that the average perceived noise level has been reduced by about 20 decibels (dB). Studies also show that, depending on the size of the airport, the aircraft fleet mix, and the actual growth in air travel, another 15 to 17 dB reduction will be required to achieve NASAs long-term goal of providing technologies to limit objectionable noise to the boundaries of an average airport.

  13. Aircraft Engine Technology for Green Aviation to Reduce Fuel Burn

    NASA Technical Reports Server (NTRS)

    Hughes, Christopher E.; VanZante, Dale E.; Heidmann, James D.

    2013-01-01

    The NASA Fundamental Aeronautics Program Subsonic Fixed Wing Project and Integrated Systems Research Program Environmentally Responsible Aviation Project in the Aeronautics Research Mission Directorate are conducting research on advanced aircraft technology to address the environmental goals of reducing fuel burn, noise and NOx emissions for aircraft in 2020 and beyond. Both Projects, in collaborative partnerships with U.S. Industry, Academia, and other Government Agencies, have made significant progress toward reaching the N+2 (2020) and N+3 (beyond 2025) installed fuel burn goals by fundamental aircraft engine technology development, subscale component experimental investigations, full scale integrated systems validation testing, and development validation of state of the art computation design and analysis codes. Specific areas of propulsion technology research are discussed and progress to date.

  14. Engine Conceptual Design Studies for a Hybrid Wing Body Aircraft

    NASA Technical Reports Server (NTRS)

    Tong, Michael T.; Jones, Scott M.; Haller, William J.; Handschuh, Robert F.

    2009-01-01

    Worldwide concerns of air quality and climate change have made environmental protection one of the most critical issues in aviation today. NASA s current Fundamental Aeronautics Research program is directed at three generations of aircraft in the near, mid and far term, with initial operating capability around 2015, 2020, and 2030, respectively. Each generation has associated goals for fuel burn, NOx, noise, and field-length reductions relative to today s aircrafts. The research for the 2020 generation is directed at enabling a hybrid wing body (HWB) aircraft to meet NASA s aggressive technology goals. This paper presents the conceptual cycle and mechanical designs of the two engine concepts, podded and embedded systems, which were proposed for a HWB cargo freighter. They are expected to offer significant benefits in noise reductions without compromising the fuel burn.

  15. Computational Analysis of a Low-Boom Supersonic Inlet

    NASA Technical Reports Server (NTRS)

    Chima, Rodrick V.

    2011-01-01

    A low-boom supersonic inlet was designed for use on a conceptual small supersonic aircraft that would cruise with an over-wing Mach number of 1.7. The inlet was designed to minimize external overpressures, and used a novel bypass duct to divert the highest shock losses around the engine. The Wind-US CFD code was used to predict the effects of capture ratio, struts, bypass design, and angles of attack on inlet performance. The inlet was tested in the 8-ft by 6-ft Supersonic Wind Tunnel at NASA Glenn Research Center. Test results showed that the inlet had excellent performance, with capture ratios near one, a peak core total pressure recovery of 96 percent, and a stable operating range much larger than that of an engine. Predictions generally compared very well with the experimental data, and were used to help interpret some of the experimental results.

  16. Aircraft Turbine Engine Monitoring Experience: Implications for the F100 Engine Diagnostic System Program

    DTIC Science & Technology

    1979-04-01

    malfunction re- port data were obtained from the Program Office. -8- EHMS (T-38 / J85 ) ACTIVITY OUTCOMES JULY 76 - MAY 77 INSTRUMENTED ENGINES CONTROL...interesting to note that the J85 was a mature engine and that the number of engine problems encountered was not very great. Also, the EHMS was not a new...copyright notation hereon. Library of Congress Cataloging In PObNiation Data Birkier, John L Aircraft turbine engine monitoring experience. ([Report

  17. Coastal Inlets Research Program

    DTIC Science & Technology

    2015-02-09

    FEB 2015 2. REPORT TYPE 3. DATES COVERED 00-00-2015 to 00-00-2015 4. TITLE AND SUBTITLE Coastal Inlets Research Program 5a. CONTRACT NUMBER...S) AND ADDRESS(ES) U.S. Army Engineer Research and Development Center,CIRP - The Coastal Inlets Research Program,3909 Halls Ferry Road,Vicksburg,MS...CIRP.aspx Coastal Inlets Research Program The Coastal Inlets Research Program (CIRP) is a R&D Program funded through the Operations & Maintenance

  18. A Study on Aircraft Structure and Jet Engine

    NASA Astrophysics Data System (ADS)

    Park, Gil Moon; Park, Hwan Kyu; Kim, Jong Il; Kim, Jin Won; Kim, Jin Heung; Lee, Moo Seok; Chung, Nak Kyu

    1985-12-01

    The one of critical factor in gas turbine engine performance is high turbine inlet gas temperature. Therefore, the turbine rotor has so many problems which must be considered such as the turbine blade cooling, thermal stress of turbine disk due to severe temperature gradient, turbine rotor tip clearance, under the high operation temperature. The purpose of this study is to provide the temperature distribution and heat flux in turbine disk which is required to considered premensioned problem by the Finite Difference Method and the Finite Element Methods on the steady state condition.

  19. Quiet Clean Short-Haul Experimental Engine (QCSEE) aerodynamic characteristics of 30.5 centimeter diameter inlets

    NASA Technical Reports Server (NTRS)

    Paul, D. L.

    1975-01-01

    A low speed test program was conducted in a 9- by 15-foot V/STOL wind tunnel to investigate internal performance characteristics and determine key design features required for an inlet to meet the demanding operational conditions of the QCSEE application. Four models each having a design average throat Mach number of 0.79 were tested over a range of incidence angle, throat Mach number, and freestream velocity. Principal design variable was internal lip diameter ratio. Stable, efficient inlet performance was found to be feasible at and beyond the 50 deg incidence angle required by the QCSEE application at its 41.2 m/sec (80 knot) nominal takeoff velocity, through suitably designed inlet lip and diffuser components. Forebody design was found to significantly impact flow stability via nose curvature. Measured inlet wall pressures were used to select a location for the inlet throat Mach number control's static pressure port that properly balanced the conflicting demands of relative insensitivity to flow incidence and sufficiently high response to changes in engine flow demand.

  20. An Extended Combustion Model for the Aircraft Turbojet Engine

    NASA Astrophysics Data System (ADS)

    Rotaru, Constantin; Andres-Mihăilă, Mihai; Matei, Pericle Gabriel

    2014-08-01

    The paper consists in modelling and simulation of the combustion in a turbojet engine in order to find optimal characteristics of the burning process and the optimal shape of combustion chambers. The main focus of this paper is to find a new configuration of the aircraft engine combustion chambers, namely an engine with two main combustion chambers, one on the same position like in classical configuration, between compressor and turbine and the other, placed behind the turbine but not performing the role of the afterburning. This constructive solution could allow a lower engine rotational speed, a lower temperature in front of the first stage of the turbine and the possibility to increase the turbine pressure ratio by extracting the flow stream after turbine in the inner nozzle. Also, a higher thermodynamic cycle efficiency and thrust in comparison to traditional constant-pressure combustion gas turbine engines could be obtained.

  1. Primary VOC emissions from Commercial Aircraft Jet Engines

    NASA Astrophysics Data System (ADS)

    Kilic, Dogushan; Huang, Rujin; Slowik, Jay; Brem, Benjamin; Durdina, Lukas; Rindlisbacher, Theo; Baltensperger, Urs; Prevot, Andre

    2014-05-01

    Air traffic is growing continuously [1]. The increasing number of airplanes leads to an increase of aviation emissions giving rise to environmental concerns globally by high altitude emissions and, locally on air quality at the ground level [2]. The overall impact of aviation emissions on the environment is likely to increase when the growing air transportation trend [2] is considered. The Aviation Particle Regulatory Instrumentation Demonstration Experiment (APRIDE)-5 campaign took place at Zurich Airport in 2013. In this campaign, aircraft exhaust is sampled during engine acceptance tests after engine overhaul at the facilities of SR Technics. Direct sampling from the engine core is made possible due to the unique fixed installation of a retractable sampling probe and the use of a standardized sampling system designed for the new particulate matter regulation in development for aircraft engines. Many of the gas-phase aircraft emissions, e.g. CO2, NOX, CO, SO2, hydrocarbons, and volatile organic compounds (VOC) were detected by the instruments in use. This study, part of the APRIDE-5 campaign, focuses on the primary VOC emissions in order to produce emission factors of VOC species for varying engine operating conditions which are the surrogates for the flight cycles. Previously, aircraft plumes were sampled in order to quantify VOCs by a proton transfer reaction quadrupole mass spectrometer (PTR-MS) [3]. This earlier study provided a preliminary knowledge on the emission of species such as methanol, acetaldehyde, acetone, benzene and toluene by varying engine thrust levels. The new setup was (i) designed to sample from the diluted engine exhaust and the new tool and (ii) used a high resolution time of flight PTR-MS with higher accuracy for many new species, therefore providing a more detailed and accurate inventory. We will present the emission factors for species that were quantified previously, as well as for many additional VOCs detected during the campaign

  2. Cobalt: A vital element in the aircraft engine industry

    NASA Technical Reports Server (NTRS)

    Stephens, J. R.

    1981-01-01

    Recent trends in the United States consumption of cobalt indicate that superalloys for aircraft engine manufacture require increasing amounts of this strategic element. Superalloys consume a lion's share of total U.S. cobalt usage which was about 16 million pounds in 1980. In excess of 90 percent of the cobalt used in this country was imported, principally from the African countries of Zaire and Zambia. Early studies on the roles of cobalt as an alloying element in high temperature alloys concentrated on the simple Ni-Cr and Nimonic alloy series. The role of cobalt in current complex nickel base superalloys is not well defined and indeed, the need for the high concentration of cobalt in widely used nickel base superalloys is not firmly established. The current cobalt situation is reviewed as it applies to superalloys and the opportunities for research to reduce the consumption of cobalt in the aircraft engine industry are described.

  3. Carbureting conditions characteristics of aircraft engines

    NASA Technical Reports Server (NTRS)

    Tice, Percival S

    1920-01-01

    Tests were conducted at the altitude laboratory erected at the Bureau of Standards for the National Advisory Committee for Aeronautics to determine the changes in engine performance with changes in atmospheric temperature and pressure at various levels above the earth's surface, with special reference to (a) the variables affecting the functioning of the carburetor and (b) the changes in performance resulting from variables in the carburetor itself. This report constitutes a concise statement of the difficulties to be encountered in this branch of carburetion.

  4. Rapid Measurement of Emissions From Military Aircraft Turbine Engines by Downstream Extractive Sampling of Aircraft on the Ground: Results for C-130 and F-15 Aircraft (POSTPRINT)

    DTIC Science & Technology

    2009-02-01

    engines were tested using indoor engine test facilities (F110, F101, J85 -GE-5M, PT6A-68, TF41-A2, TF30-P103 and TF30- P109), while others were studied while...afterburning). Engine T56-A-15 F100-PW-100 F110 F101 J85 -GE-5M PT6A-68 TF-39-1C CFM-56-3 TF41-A2 TF30-P103 TF30-P109 Misc. Type Turboprop Turbofan...AIRCRAFT TURBINE ENGINES BY DOWNSTREAM EXTRACTIVE SAMPLING OF AIRCRAFT ON THE GROUND: RESULTS FOR C-130 AND F-15 AIRCRAFT Chester Spicer and

  5. Acoustic performance of inlet suppressors on an engine generating a single mode

    NASA Technical Reports Server (NTRS)

    Heidelberg, L. J.; Rice, E. J.; Homyak, L.

    1981-01-01

    Three single degree of freedom liners with different open area ratio face sheets were designed for a single spinning mode in order to evaluate an inlet suppressor design method based on mode cutoff ratio. This mode was generated by placing 41 rods in front of the 28 blade fan of a JT15D turbofan engine. At the liner design this near cutoff mode has a theoretical maximum attenuation of nearly 200 dB per L/D. The data show even higher attenuations at the design condition than predicted by the theory for dissipation of a single mode within the liner. This additional attenuation is large for high open area ratios and should be accounted for in the theory. The data show the additional attenuation to be inversely proportional to acoustic resistance. It was thought that the additional attenuation could be caused by reflection and modal scattering at the hard to soft wall interface. A reflection model was developed, and then modified to fit the data. This model was checked against independent (multiple pure tone) data with good agreement.

  6. Neural net controller for inlet pressure control of rocket engine testing

    NASA Technical Reports Server (NTRS)

    Trevino, Luis C.

    1994-01-01

    Many dynamic systems operate in select operating regions, each exhibiting characteristic modes of behavior. It is traditional to employ standard adjustable gain proportional-integral-derivative (PID) loops in such systems where no apriori model information is available. However, for controlling inlet pressure for rocket engine testing, problems in fine tuning, disturbance accommodation, and control gains for new profile operating regions (for research and development) are typically encountered. Because of the capability of capturing I/O peculiarities, using NETS, a back propagation trained neural network is specified. For select operating regions, the neural network controller is simulated to be as robust as the PID controller. For a comparative analysis, the higher order moment neural array (HOMNA) method is used to specify a second neural controller by extracting critical exemplars from the I/O data set. Furthermore, using the critical exemplars from the HOMNA method, a third neural controller is developed using NETS back propagation algorithm. All controllers are benchmarked against each other.

  7. 76 FR 19903 - Special Conditions: Diamond Aircraft Industry Model DA-40NG; Diesel Cycle Engine

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-11

    ... Conditions: Diamond Aircraft Industry Model DA-40NG; Diesel Cycle Engine AGENCY: Federal Aviation... conditions are issued for the Diamond Aircraft Industry (DAI) GmbH model DA-40NG the Austro Engine GmbH model... the postcard and mail it back to you. Background On May 11, 2010 Diamond Aircraft Industry...

  8. Computation of Engine Noise Propagation and Scattering Off an Aircraft

    NASA Technical Reports Server (NTRS)

    Xu, J.; Stanescu, D.; Hussaini, M. Y.; Farassat, F.

    2003-01-01

    The paper presents a comparison of experimental noise data measured in flight on a two-engine business jet aircraft with Kulite microphones placed on the suction surface of the wing with computational results. Both a time-domain discontinuous Galerkin spectral method and a frequency-domain spectral element method are used to simulate the radiation of the dominant spinning mode from the engine and its reflection and scattering by the fuselage and the wing. Both methods are implemented in computer codes that use the distributed memory model to make use of large parallel architectures. The results show that trends of the noise field are well predicted by both methods.

  9. TCM aircraft piston engine emission reduction program

    NASA Technical Reports Server (NTRS)

    Rezy, B. J.

    1976-01-01

    The technology necessary to safely reduce general aviation piston engine exhaust emissions to meet the EPA 1980 Emission Standards with minimum adverse effects on cost, weight, fuel economy, and performance was demonstrated. A screening and assessment of promising emission reduction concepts was provided, and the preliminary design and development of those concepts was established. A system analysis study and a decision making procedure were used by TCM to evaluate, trade off, and rank the candidate concepts from a list of 14 alternatives. Cost, emissions, and 13 other design criteria considerations were defined and traded off against each candidate concept to establish its merit and emission reduction usefulness. A computer program was used to aid the evaluators in making the final choice of three concepts.

  10. 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.

  11. Altitude-Wind-Tunnel Investigation of a 3000-Pound-Thrust Axial-Flow Turbojet Engine. 6; Analysis of Effects of Inlet Pressure Losses

    NASA Technical Reports Server (NTRS)

    Sanders, Newell D.; Palasics, John

    1948-01-01

    The losses in the inlet air ducts, the diffusers, and the de-icing equipment associated with turbojet engine installations cause a reduction in the total pressure at the inlet of the engine and result in reduced thrust and increased specific fuel consumption. An analytical evaluation of the effects of inlet losses on the net thrust and the fuel economy of a 3000-pound-thrust axial flow turbojet engine with a two-stage turbine is presented. The analysis is based on engine performance characteristics that were determined from experiments in the NACA Cleveland altitude wind tunnel. The experimental investigation did not include tests in which inlet losses were systematically varied, but the effects of these losses can be accurately estimated from the experimentally determined performance characteristics of the engine.

  12. Hypersonic aircraft design

    NASA Technical Reports Server (NTRS)

    Alkamhawi, Hani; Greiner, Tom; Fuerst, Gerry; Luich, Shawn; Stonebraker, Bob; Wray, Todd

    1990-01-01

    A hypersonic aircraft is designed which uses scramjets to accelerate from Mach 6 to Mach 10 and sustain that speed for two minutes. Different propulsion systems were considered and it was decided that the aircraft would use one full scale turbofan-ramjet. Two solid rocket boosters were added to save fuel and help the aircraft pass through the transonic region. After considering aerodynamics, aircraft design, stability and control, cooling systems, mission profile, and landing systems, a conventional aircraft configuration was chosen over that of a waverider. The conventional design was chosen due to its landing characteristics and the relative expense compared to the waverider. Fuel requirements and the integration of the engine systems and their inlets are also taken into consideration in the final design. A hypersonic aircraft was designed which uses scramjets to accelerate from Mach 6 to Mach 10 and sustain that speed for two minutes. Different propulsion systems were considered and a full scale turbofan-ramjet was chosen. Two solid rocket boosters were added to save fuel and help the aircraft pass through the transonic reqion. After the aerodynamics, aircraft design, stability and control, cooling systems, mission profile, landing systems, and their physical interactions were considered, a conventional aircraft configuration was chosen over that of a waverider. The conventional design was chosen due to its landing characteristics and the relative expense compared to the waverider. Fuel requirements and the integration of the engine systems and their inlets were also considered in the designing process.

  13. CFD simulations of the flow control performance applied for inlet of low drag high-bypass turbofan engine at cross flow regimes

    NASA Astrophysics Data System (ADS)

    Kursakov, I. A.; Kazhan, E. V.; Lysenkov, A. V.; Savelyev, A. A.

    2016-10-01

    Paper describes the optimization procedure for low cruise drag inlet of high-bypass ratio turbofan engine (HBRE). The critical cross-flow velocity when the flow separation on the lee side of the inlet channel occurs is determined. The effciency of different flow control devices used to improve the flow parameters at inlet section cross flow regime is analyzed. Boundary layer suction, bypass slot and vortex generators are considered. It is shown that flow control devices enlarge the stability range of inlet performance at cross flow regimes.

  14. Experimental Investigation of Water Droplet Impingement on Airfoils, Finite Wings, and an S-duct Engine Inlet

    NASA Technical Reports Server (NTRS)

    Papadakis, Michael; Hung, Kuohsing E.; Vu, Giao T.; Yeong, Hsiung Wei; Bidwell, Colin S.; Breer, Martin D.; Bencic, Timothy J.

    2002-01-01

    Validation of trajectory computer codes, for icing analysis, requires experimental water droplet impingement data for a wide range of aircraft geometries as well as flow and icing conditions. This report presents improved experimental and data reduction methods for obtaining water droplet impingement data and provides a comprehensive water droplet impingement database for a range of test geometries including an MS(1)-0317 airfoil, a GLC-305 airfoil, an NACA 65(sub 2)-415 airfoil, a commercial transport tail section, a 36-inch chord natural laminar flow NLF(1)-0414 airfoil, a 48-inch NLF(1)-0414 section with a 25 percent chord simple flap, a state-of-the-art three-element high lift system, a NACA 64A008 finite span swept business jet tail, a full-scale business jet horizontal tail section, a 25 percent-scale business jet empennage, and an S-duct turboprop engine inlet. The experimental results were obtained at the NASA Glenn Icing Research Tunnel (IRT) for spray clouds with median volumetric diameter (MVD) of 11, 11.5, 21, 92, and 94 microns and for a range of angles of attack. The majority of the impingement experiments were conducted at an air speed of 175 mph corresponding to a Reynolds number of approximately 1.6 million per foot. The maximum difference of repeated tests from the average ranged from 0.24 to 12 percent for most of the experimental results presented. This represents a significant improvement in test repeatability compared to previous experimental studies. The increase in test repeatability was attributed to improvements made to the experimental and data reduction methods. Computations performed with the LEWICE-2D and LEWICE-3D computer codes for all test configurations are presented in this report. For the test cases involving median volumetric diameters of 11 and 21 microns, the correlation between the analytical and experimental impingement efficiency distributions was good. For the median volumetric diameters of 92 and 94-micron cases, however

  15. A study of external fuel vaporization. [for aircraft gas turbine engines

    NASA Technical Reports Server (NTRS)

    Szetela, E. J.; Chiappetta, L.; Baker, C. E.

    1981-01-01

    Candidate external vaporizer designs for an aircraft gas turbine engine are evaluated with respect to fuel thermal stability, integration of the vaporizer system into the aircraft engine, engine and vaporizer dynamic response, startup and altitude restart, engine performance, control requirements, safety, and maintenance. The selected concept is shown to offer potential gains in engine performance in terms of reduced specific fuel consumption and improved engine thrust/weight ratio. The thrust/weight improvement can be traded against vaporization system weight.

  16. Characterization of emissions from commercial aircraft engines during the Aircraft Particle Emissions eXperiment (APEX) 1 to 3

    EPA Science Inventory

    The fine particulate matter emissions from aircraft operations at large airports located in areas of the U. S. designated as non-attainment for the National Ambient Air Quality Standard for PM-2.5 are of major environmental concern. PM emissions data for commercial aircraft engin...

  17. 76 FR 45011 - Control of Air Pollution From Aircraft and Aircraft Engines; Proposed Emission Standards and Test...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-27

    ... Environmental Protection Agency 40 CFR Parts 87 and 1068 Control of Air Pollution From Aircraft and Aircraft... AGENCY 40 CFR Parts 87 and 1068 [EPA-HQ-OAR-2010-0687; FRL-9437-2] RIN 2060-AO70 Control of Air Pollution... engines which in her judgment causes or contributes to air pollution that may reasonably be anticipated...

  18. 77 FR 65823 - Control of Air Pollution From Aircraft and Aircraft Engines; Emission Standards and Test Procedures

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-31

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY 40 CFR Parts 87 RIN 2060-AO70 Control of Air Pollution From Aircraft and Aircraft Engines; Emission Standards and Test Procedures Correction In rule document 2012-13828 appearing on pages...

  19. 77 FR 36341 - Control of Air Pollution From Aircraft and Aircraft Engines; Emission Standards and Test Procedures

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-18

    ... nitrogen (NO X ), compliance flexibilities, and other regulatory requirements for aircraft turbofan or... Exposure to Ozone, PM and NO X a. Deposition of Nitrogen b. Visibility Effects c. Plant and Ecosystem... nitrogen (NO X ) emission standards for aircraft engines with rated thrusts greater than 26.7 kN...

  20. Internal flow characteristics of a multistage compressor with inlet pressure distortion. [J85-13 turbojet engine studies

    NASA Technical Reports Server (NTRS)

    Debogdan, C. E.; Moss, J. E., Jr.; Braithwaite, W. M.

    1977-01-01

    The measured distribution of compressor interstage pressures and temperatures resulting from a 180 deg inlet-total-pressure distortion for a J85-13 turbojet engine is reported. Extensive inner stage instrumentation combined with stepwise rotation of the inlet distortion gave data of high circumferential resolution. The steady-state pressures and temperatures along with the amplitude, extent, and location of the distorted areas are given. Data for 80, 90, and 100 percent of rotor design speed are compared with clean (undistorted) inlet flow conditions to show pressure and temperature behavior within the compressor. Both overall and stagewise compressor performances vary only slightly when clean and distorted inlet conditions are compared. Total and static pressure distortions increase in amplitude in the first few stages of the compressor and then attenuate fairly uniformly to zero at the discharge. Total-temperature distortion induced by the pressure distortion reached a maximum amplitude by the first two stages and decayed only a little through the rest of the compressor. Distortion amplitude tended to peak in line with the screen edges, and, except for total and static pressure in the tip zone, there was little swirl in the axial direction.

  1. Aerodynamic analysis of several high throat Mach number inlets for the quiet clean short-haul experimental engine

    NASA Technical Reports Server (NTRS)

    Albers, J. A.; Stockman, N. O.; Hirn, J. J.

    1975-01-01

    The results of an analytical study to investigate internal and external surface Mach numbers on several inlet geometries for possible application to the nacelle of the Quiet Clean Short-Haul Experimental Engine (QCSEE) are presented. The effects of external forebody geometry and internal lip geometry were illustrated at both low-speed and cruise conditions. Boundary-layer analyses were performed on several geometries to determine if lip flow separation might exist. The results indicated that inner-surface Mach number level and gradient could be reduced with inlets at a 50 deg incidence angle by blunting the external forebody geometry. The external Mach numbers at cruise conditions indicated that a compromise in the external forebody bluntness might be required to satisfy both low-speed and cruise conditions. For a fixed value of bluntness parameter, no lip flow separation was indicated for the 1.46- and 1.57-area-contraction-ratio inlets at low-speed conditions. However, a lip separation condition was obtained with the 1.37-contraction-ratio inlet. The QCSEE nacelle design takeoff operating condition (incidence angle of 50 deg and free-stream Mach number of 0.12) resulted in higher peak surface Mach numbers than the design crosswind (incidence angle of 90 deg and free-stream Mach number of 0.05) or static condition.

  2. A study of engine variable geometry systems for an advanced high subsonic long range commercial aircraft

    NASA Technical Reports Server (NTRS)

    Compagnon, M. A.

    1973-01-01

    Several variable geometry high Mach inlet concepts, aimed at meeting a system noise objective of 15 EPNdB below FAR part 36, for a long range, Mach 0.9 advanced commercial transport are assessed and compared to a fixed geometry inlet with multiple splitters. The effects of a variable exhaust nozzle (mixed exhaust engine) on noise, inlet geometry requirements, and economics are also presented. The best variable geometry inlet configuration identified is a variable cowl design which relies on a high throat Mach number for additional inlet noise suppression only at takeoff, and depends entirely on inlet wall treatment for noise suppression at approach power. Relative economic penalties as a function of noise level are also presented.

  3. Aircraft Engine Noise Scattering - A Discontinuous Spectral Element Approach

    NASA Technical Reports Server (NTRS)

    Stanescu, D.; Hussaini, M. Y.; Farassat, F.

    2002-01-01

    The paper presents a time-domain method for computation of sound radiation from aircraft engine sources to the far-field. The effects of nonuniform flow around the aircraft and scattering of sound by fuselage and wings are accounted for in the formulation. Our approach is based on the discretization of the inviscid flow equations through a collocation form of the Discontinuous Galerkin spectral element method. An isoparametric representation of the underlying geometry is used in order to take full advantage of the spectral accuracy of the method. Largescale computations are made possible by a parallel implementation based on message passing. Results obtained for radiation from an axisymmetric nacelle alone are compared with those obtained when the same nacelle is installed in a generic con.guration, with and without a wing.

  4. Aircraft Engine Gas Path Diagnostic Methods: Public Benchmarking Results

    NASA Technical Reports Server (NTRS)

    Simon, Donald L.; Borguet, Sebastien; Leonard, Olivier; Zhang, Xiaodong (Frank)

    2013-01-01

    Recent technology reviews have identified the need for objective assessments of aircraft engine health management (EHM) technologies. To help address this issue, a gas path diagnostic benchmark problem has been created and made publicly available. This software tool, referred to as the Propulsion Diagnostic Method Evaluation Strategy (ProDiMES), has been constructed based on feedback provided by the aircraft EHM community. It provides a standard benchmark problem enabling users to develop, evaluate and compare diagnostic methods. This paper will present an overview of ProDiMES along with a description of four gas path diagnostic methods developed and applied to the problem. These methods, which include analytical and empirical diagnostic techniques, will be described and associated blind-test-case metric results will be presented and compared. Lessons learned along with recommendations for improving the public benchmarking processes will also be presented and discussed.

  5. Control of Inflow Distortion in a Scarf Inlet

    NASA Technical Reports Server (NTRS)

    Gerhold, Carl H.; Clark, Lorenzo R.; Biedron, Robert T.

    2002-01-01

    The scarf inlet has the potential to reduce aircraft inlet noise radiation to the ground by reflecting it into the space above the engine. Without forward motion of the engine, the non-symmetry of the inlet causes inflow distortion which generates noise that is greater than the noise reduction of the scarf. However, acoustic evaluations of aircraft engines are often done on static test stands. A method to reduce inflow distortion by boundary layer suction is proposed and evaluated using a model of a high bypass ratio engine located in an anechoic chamber. The design goal of the flow control system is to make the inflow to the inlet circumferentially uniform and to eliminate reversed flow. This minimizes the inflow distortion and allows for acoustic evaluation of the scarf inlet on a static test stand. The inlet boundary layer suction effectiveness is evaluated both by aerodynamic and by acoustic measurements. Although the design goal is not met, the control system is found to have a beneficial effect on the engine operation, reducing blade stall and speed variation. This is quantified by two acoustic benefits, reduction both of the variability of tone noise and of the low frequency wideband noise due to the inflow distortion. It is felt that a compromise in the manufacture of the control hardware contributes to the inability of the control system to perform as expected from the analysis. The control system with sufficient authority is felt to have the potential to permit reliable acoustic testing in a static configuration of engines with non-symmetric inlets. Because the control system can improve operation of the engine, it may also have the potential to reduce noise and vibration and enhance engine longevity during low speed ground operations in the terminal area.

  6. Lightweight diesel engine designs for commuter type aircraft

    NASA Technical Reports Server (NTRS)

    Brouwers, A. P.

    1981-01-01

    Conceptual designs and performance of advanced technology lightweight diesel engines, suitable for commuter type aircraft power plants are defined. Two engines are discussed, a 1491 kW (2000 SHP) eight-cylinder engine and a 895 kW (1200 SHP) six-cylinder engine. High performance and related advanced technologies are proposed such as insulated cylinders, very high injection pressures and high compressor and turbine efficiencies. The description of each engine includes concept drawings, a performance analysis, and weight data. Fuel flow data are given for full and partial power up to 7620m altitude. The performance data are also extrapolated over a power range from 671 kW(900SHP) to 1864 kW (2500 SHP). The specific fuel consumption of the 1491 kW (2000 SHP) engine is 182 g/hWh (.299 lb/HPh) at cruise altitude, its weight 620 kg (1365 lb.) and specific weight .415 kg/kW (.683 lb/HP). The specific fuel consumption of the 895 kW (1200 SHP) engine is 187 g/hWh (.308 lb/HPh) at cruise altitude, its weight 465 kg (1025 lb.) and specific weight .520 kg/kW (.854 lb/HP).

  7. Performance of 4600-pound-thrust centrifugal-flow-type turbojet engine with water-alcohol injection at inlet

    NASA Technical Reports Server (NTRS)

    Glasser, Philip W

    1950-01-01

    An experimental investigation of the effects of injecting a water-alcohol mixture of 2:1 at the compressor inlet of a centrifugal-flow type turbojet engine was conducted in an altitude test chamber at static sea-level conditions and at an altitude of 20,000 feet with a flight Mach number of 0.78 with an engine operating at rated speed. The net thrust was augmented by 0.16 for both flight conditions with a ratio of injected liquid to air flow of 0.05. Further increases in the liquid-air ratio did not give comparable increases in thrust.

  8. The knocking characteristics of fuels in relation to maximum permissible performance of aircraft engines

    NASA Technical Reports Server (NTRS)

    Rothrock, A M; Biermann, Arnold E

    1939-01-01

    An analysis is presented of the relationship of various engine factors to knock in preignition in an aircraft engine. From this analysis and from the available experimental data, a method of evaluating the knocking characteristics of the fuel in an aircraft-engine cylinder is suggested.

  9. Life-Extending Control for Aircraft Engines Studied

    NASA Technical Reports Server (NTRS)

    Guo, Te-Huei

    2002-01-01

    Current aircraft engine controllers are designed and operated to provide both performance and stability margins. However, the standard method of operation results in significant wear and tear on the engine and negatively affects the on-wing life--the time between cycles when the engine must be physically removed from the aircraft for maintenance. The NASA Glenn Research Center and its industrial and academic partners have been working together toward a new control concept that will include engine life usage as part of the control function. The resulting controller will be able to significantly extend the engine's on-wing life with little or no impact on engine performance and operability. The new controller design will utilize damage models to estimate and mitigate the rate and overall accumulation of damage to critical engine parts. The control methods will also provide a means to assess tradeoffs between performance and structural durability on the basis of mission requirements and remaining engine life. Two life-extending control methodologies were studied to reduce the overall life-cycle cost of aircraft engines. The first methodology is to modify the baseline control logic to reduce the thermomechanical fatigue (TMF) damage of cooled stators during acceleration. To accomplish this, an innovative algorithm limits the low-speed rotor acceleration command when the engine has reached a threshold close to the requested thrust. This algorithm allows a significant reduction in TMF damage with only a very small increase in the rise time to reach the commanded rotor speed. The second methodology is to reduce stress rupture/creep damage to turbine blades and uncooled stators by incorporating an engine damage model into the flight mission. Overall operation cost is reduced by an optimization among the flight time, fuel consumption, and component damages. Recent efforts have focused on applying life-extending control technology to an existing commercial turbine engine

  10. A Study of Bird Ingestions Into Large High Bypass Ratio Turbine Aircraft Engines.

    DTIC Science & Technology

    1983-03-01

    into large high bypass ratio turbine aircraft engines on a worldwide basis and what damage , if any, resulted. This interim report presents a summary...operations. These aircraft experienced 289 engine ingestion events during the initial contract * period, May 1961 through April 1982. The FAA is...Airports involved 88 3. Total events 289 4. hngine damage , minor and/or major 188 5. Multiple engine ingestions per aircraft 11 6. MuLtiple bird

  11. Experimental Studies of Coal and Biomass Fuel Synthesis and Flame Characterization for Aircraft Engines

    DTIC Science & Technology

    2012-03-31

    Synthesis and Flame Characterization for Aircraft Engines 5a. CONTRACT NUMBER 5b. GRANT NUMBER FA9550-10-1-0344 5c. PROGRAM ELEMENT NUMBER 61102F... Flame Characterization for Aircraft Engines AFOSR Grant Number: FA9550-10-1-0344 Final Performance Report Report Period: September 1, 2008 to... Flame Characterization for Aircraft Engines (Final Performance Report) Project Period: September 1, 2008 to March 31, 2012 Report Period

  12. Comparison of the Aeroacoustics of Two Small-Scale Supersonic Inlets

    NASA Technical Reports Server (NTRS)

    Ng, Wing

    1996-01-01

    An aerodynamic and acoustic investigation was performed on two small-scale supersonic inlets to determine which inlet would be more suitable for a High Speed Civil Transport (HSCT) aircraft during approach and takeoff flight conditions. The comparison was made between an axisymmetric supersonic P inlet and a bifurcated two-dimensional supersonic inlet. The 1/14 scale model supersonic inlets were used in conjunction with a 4.1 in (10.4 cm) turbofan engine simulator. A bellmouth was utilized on each inlet to eliminate lip separation commonly associated with airplane engine inlets that are tested under static conditions. Steady state measurements of the aerodynamic flowfield and acoustic farfield were made in order to evaluate the aeroacoustic performance of the inlets. The aerodynamic results show the total pressure recovery of the two inlets to be nearly identical, 99% at the approach condition and 98% at the takeoff condition. At the approach fan speed (60% design speed), there was no appreciable difference in the acoustic performance of either inlet over the entire 0 deg to 110 deg farfield measurement sector. The inlet flow field results at the takeoff fan speed (88% design speed), show the average inlet throat Mach number for the P inlet (Mach 0.52) to be approximately 2 times that of the 2D inlet (Mach 0.26). The difference in the throat Mach number is a result of the smaller throughflow area of the P inlet. This reduced area resulted in a 'soft choking' of the P inlet which lowered the tone and overall sound pressure levels of the simulator in the forward sector by an average of 9 dB and 3 dB, respectively, when compared to the 2D inlet.

  13. Preliminary Results of the Determination of Inlet-Pressure Distortion Effects on Compressor Stall and Altitude Operating Limits of the J57-P-1 Turbojet Engine

    NASA Technical Reports Server (NTRS)

    Wallner, L. E.; Lubick, R. J.; Chelko, L. J.

    1955-01-01

    During an investigation of the J57-P-1 turbojet engine in the Lewis altitude wind tunnel, effects of inlet-flow distortion on engine stall characteristics and operating limits were determined. In addition to a uniform inlet-flow profile, the inlet-pressure distortions imposed included two radial, two circumferential, and one combined radial-circumferential profile. Data were obtained over a range of compressor speeds at an altitude of 50,000 and a flight Mach number of 0.8; in addition, the high- and low-speed engine operating limits were investigated up to the maximum operable altitude. The effect of changing the compressor bleed position on the stall and operating limits was determined for one of the inlet distortions. The circumferential distortions lowered the compressor stall pressure ratios; this resulted in less fuel-flow margin between steady-state operation and compressor stall. Consequently, the altitude operating Limits with circumferential distortions were reduced compared with the uniform inlet profile. Radial inlet-pressure distortions increased the pressure ratio required for compressor stall over that obtained with uniform inlet flow; this resulted in higher altitude operating limits. Likewise, the stall-limit fuel flows required with the radial inlet-pressure distortions were considerably higher than those obtained with the uniform inlet-pressure profile. A combined radial-circumferential inlet distortion had effects on the engine similar to the circumferential distortion. Bleeding air between the two compressors eliminated the low-speed stall limit and thus permitted higher altitude operation than was possible without compressor bleed.

  14. Development and Characterization Testing of an Air Pulsation Valve for a Pulse Detonation Engine Supersonic Parametric Inlet Test Section

    NASA Technical Reports Server (NTRS)

    Tornabene, Robert

    2005-01-01

    In pulse detonation engines, the potential exists for gas pulses from the combustor to travel upstream and adversely affect the inlet performance of the engine. In order to determine the effect of these high frequency pulses on the inlet performance, an air pulsation valve was developed to provide air pulses downstream of a supersonic parametric inlet test section. The purpose of this report is to document the design and characterization tests that were performed on a pulsation valve that was tested at the NASA Glenn Research Center 1x1 Supersonic Wind Tunnel (SWT) test facility. The high air flow pulsation valve design philosophy and analyses performed are discussed and characterization test results are presented. The pulsation valve model was devised based on the concept of using a free spinning ball valve driven from a variable speed electric motor to generate air flow pulses at preset frequencies. In order to deliver the proper flow rate, the flow port was contoured to maximize flow rate and minimize pressure drop. To obtain sharp pressure spikes the valve flow port was designed to be as narrow as possible to minimize port dwell time.

  15. Near-field commercial aircraft contribution to nitrogen oxides by engine, aircraft type, and airline by individual plume sampling.

    PubMed

    Carslaw, David C; Ropkins, Karl; Laxen, Duncan; Moorcroft, Stephen; Marner, Ben; Williams, Martin L

    2008-03-15

    Nitrogen oxides (NOx) concentrations were measured in individual plumes from aircraft departing on the northern runway at Heathrow Airport in west London. Over a period of four weeks 5618 individual plumes were sampled by a chemiluminescence monitor located 180 m from the runway. Results were processed and matched with detailed aircraft movement and aircraft engine data using chromatographic techniques. Peak concentrations associated with 29 commonly used engines were calculated and found to have a good relationship with N0x emissions taken from the International Civil Aviation Organization (ICAO) databank. However, it is found that engines with higher reported NOx emissions result in proportionately lower NOx concentrations than engines with lower emissions. We show that it is likely that aircraft operational factors such as takeoff weight and aircraftthrust setting have a measurable and important effect on concentrations of N0x. For example, NOx concentrations can differ by up to 41% for aircraft using the same airframe and engine type, while those due to the same engine type in different airframes can differ by 28%. These differences are as great as, if not greater than, the reported differences in NOx emissions between different engine manufacturers for engines used on the same airframe.

  16. 14 CFR 25.939 - Turbine engine operating characteristics.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant General § 25.939 Turbine... airplane and of the engine. (b) (c) The turbine engine air inlet system may not, as a result of air...

  17. 14 CFR 25.939 - Turbine engine operating characteristics.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant General § 25.939 Turbine... airplane and of the engine. (b) (c) The turbine engine air inlet system may not, as a result of air...

  18. 14 CFR 25.939 - Turbine engine operating characteristics.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant General § 25.939 Turbine... airplane and of the engine. (b) (c) The turbine engine air inlet system may not, as a result of air...

  19. NACA's 9th Annual Aircraft Engineering Research Conference

    NASA Technical Reports Server (NTRS)

    1934-01-01

    Eight of the twelve members of the National Advisory Committee for Aeronautics attending the 9th Annual Aircraft Engineering Research Conference posed for this photograph at Langley Field, Virginia, on May 23, 1934. Those pictured are (left to right): Brig. Gen. Charles A. Lindbergh, USAFR Vice Admiral Arthur B. Cook, USN Charles G. Abbot, Secretary of the Smithsonian Institution Dr. Joseph S. Ames, Committee Chairman Orville Wright Edward P. Warner Fleet Admiral Ernest J. King, USN Eugene L. Vidal, Director, Bureau of Air Commerce.

  20. Exhaust emission reduction for intermittent combustion aircraft engines

    NASA Technical Reports Server (NTRS)

    Moffett, R. N.

    1979-01-01

    Three concepts for optimizing the performance, increasing the fuel economy, and reducing exhaust emission of the piston aircraft engine were investigated. High energy-multiple spark discharge and spark plug tip penetration, ultrasonic fuel vaporization, and variable valve timing were evaluated individually. Ultrasonic fuel vaporization did not demonstrate sufficient improvement in distribution to offset the performance loss caused by the additional manifold restriction. High energy ignition and revised spark plug tip location provided no change in performance or emissions. Variable valve timing provided some performance benefit; however, even greater performance improvement was obtained through induction system tuning which could be accomplished with far less complexity.

  1. Structureborne noise measurements on a small twin-engine aircraft

    NASA Technical Reports Server (NTRS)

    Cole, J. E., III; Martini, K. F.

    1988-01-01

    Structureborne noise measurements performed on a twin-engine aircraft (Beechcraft Baron) are reported. There are two overall objectives of the test program. The first is to obtain data to support the development of analytical models of the wing and fuselage, while the second is to evaluate effects of structural parameters on cabin noise. Measurements performed include structural and acoustic responses to impact excitation, structural and acoustic loss factors, and modal parameters of the wing. Path alterations include added mass to simulate fuel, variations in torque of bolts joining wing and fuselage, and increased acoustic absorption. Conclusions drawn regarding these measurements are presented.

  2. Structureborne noise measurements on a small twin-engine aircraft

    NASA Astrophysics Data System (ADS)

    Cole, J. E., III; Martini, K. F.

    1988-06-01

    Structureborne noise measurements performed on a twin-engine aircraft (Beechcraft Baron) are reported. There are two overall objectives of the test program. The first is to obtain data to support the development of analytical models of the wing and fuselage, while the second is to evaluate effects of structural parameters on cabin noise. Measurements performed include structural and acoustic responses to impact excitation, structural and acoustic loss factors, and modal parameters of the wing. Path alterations include added mass to simulate fuel, variations in torque of bolts joining wing and fuselage, and increased acoustic absorption. Conclusions drawn regarding these measurements are presented.

  3. A technique for integrating engine cycle and aircraft configuration optimization

    NASA Technical Reports Server (NTRS)

    Geiselhart, Karl A.

    1994-01-01

    A method for conceptual aircraft design that incorporates the optimization of major engine design variables for a variety of cycle types was developed. The methodology should improve the lengthy screening process currently involved in selecting an appropriate engine cycle for a given application or mission. The new capability will allow environmental concerns such as airport noise and emissions to be addressed early in the design process. The ability to rapidly perform optimization and parametric variations using both engine cycle and aircraft design variables, and to see the impact on the aircraft, should provide insight and guidance for more detailed studies. A brief description of the aircraft performance and mission analysis program and the engine cycle analysis program that were used is given. A new method of predicting propulsion system weight and dimensions using thermodynamic cycle data, preliminary design, and semi-empirical techniques is introduced. Propulsion system performance and weights data generated by the program are compared with industry data and data generated using well established codes. The ability of the optimization techniques to locate an optimum is demonstrated and some of the problems that had to be solved to accomplish this are illustrated. Results from the application of the program to the analysis of three supersonic transport concepts installed with mixed flow turbofans are presented. The results from the application to a Mach 2.4, 5000 n.mi. transport indicate that the optimum bypass ratio is near 0.45 with less than 1 percent variation in minimum gross weight for bypass ratios ranging from 0.3 to 0.6. In the final application of the program, a low sonic boom fix a takeoff gross weight concept that would fly at Mach 2.0 overwater and at Mach 1.6 overland is compared with a baseline concept of the same takeoff gross weight that would fly Mach 2.4 overwater and subsonically overland. The results indicate that for the design mission

  4. An Integrated Architecture for Aircraft Engine Performance Monitoring and Fault Diagnostics: Engine Test Results

    NASA Technical Reports Server (NTRS)

    Rinehart, Aidan W.; Simon, Donald L.

    2015-01-01

    This paper presents a model-based architecture for performance trend monitoring and gas path fault diagnostics designed for analyzing streaming transient aircraft engine measurement data. The technique analyzes residuals between sensed engine outputs and model predicted outputs for fault detection and isolation purposes. Diagnostic results from the application of the approach to test data acquired from an aircraft turbofan engine are presented. The approach is found to avoid false alarms when presented nominal fault-free data. Additionally, the approach is found to successfully detect and isolate gas path seeded-faults under steady-state operating scenarios although some fault misclassifications are noted during engine transients. Recommendations for follow-on maturation and evaluation of the technique are also presented.

  5. An Integrated Architecture for Aircraft Engine Performance Monitoring and Fault Diagnostics: Engine Test Results

    NASA Technical Reports Server (NTRS)

    Rinehart, Aidan W.; Simon, Donald L.

    2014-01-01

    This paper presents a model-based architecture for performance trend monitoring and gas path fault diagnostics designed for analyzing streaming transient aircraft engine measurement data. The technique analyzes residuals between sensed engine outputs and model predicted outputs for fault detection and isolation purposes. Diagnostic results from the application of the approach to test data acquired from an aircraft turbofan engine are presented. The approach is found to avoid false alarms when presented nominal fault-free data. Additionally, the approach is found to successfully detect and isolate gas path seeded-faults under steady-state operating scenarios although some fault misclassifications are noted during engine transients. Recommendations for follow-on maturation and evaluation of the technique are also presented.

  6. Noise reduction as affected by the extent and distribution of acoustic treatment in a turbofan engine inlet

    NASA Technical Reports Server (NTRS)

    Minner, G. L.; Homyak, L.

    1976-01-01

    An inlet noise suppressor for a TF-34 engine designed to have three acoustically treated rings was tested with several different ring arrangements. The configurations included: all three rings; two outer rings; single outer ring; single intermediate ring, and finally no rings. It was expected that as rings were removed, the acoustic performance would be degraded considerably. While a degradation occurred, it was not as large as predictions indicated. In fact, the prediction showed good agreement with the data only for the full-ring inlet configuration. The under-predictions which occurred with ring removal were believed a result of ignoring the presence of spinning modes which are known to damp more rapidly in cylindrical ducts than would be predicted by least attenuated mode or plane wave analysis.

  7. Noise reduction as affected by the extent and distribution of acoustic treatment in a turbofan engine inlet

    NASA Technical Reports Server (NTRS)

    Minner, G. L.; Homyak, L.

    1976-01-01

    An inlet noise suppressor for a TF-34 engine designed to have three acoustically treated rings was tested with several different ring arrangements. The configurations included: all three rings; two outer rings; single outer ring; single intermediate ring, and finally no rings. It was expected that as rings were removed, the acoustic performance would be degraded considerably. While a degradation occurred, it was not as large as predictions indicated. The prediction showed good agreement with the data only for the full-ring inlet configuration. The underpredictions which occurred with ring removal were believed a result of ignoring the presence of spinning modes which are known to damp more rapidly in cylindrical ducts than would be predicted by least attenuated mode or plane wave analysis.

  8. The influence of the inlet duct contour on forward radiated fan noise

    NASA Technical Reports Server (NTRS)

    Sloan, D.; Farquhar, B. W.; Rayl, C.

    1977-01-01

    Measurements have been obtained to determine the extent to which the shape of the inlet duct affects the directivity pattern of forward radiated noise from aircraft gas turbine engines. The test program was conducted using a model fan to which were attached any of three inlet ducts with each designed to cause a particular noise directivity pattern. Existing information on the effects of wave refraction in inlet-type flow fields was used to design the duct contours. Results indicated that the shape of the inlet duct strongly influenced the radiated noise field but that wave refraction was not the dominant factor in controlling the noise directivity pattern.

  9. Improving safety of aircraft engines: a consortium approach

    NASA Astrophysics Data System (ADS)

    Brasche, Lisa J. H.

    1996-11-01

    With over seven million departures per year, air transportation has become not a luxury, but a standard mode of transportation for the United States. A critical aspect of modern air transport is the jet engine, a complex engineered component that has enabled the rapid travel to which we have all become accustomed. One of the enabling technologies for safe air travel is nondestructive evaluation, or NDE, which includes various inspection techniques used to assess the health or integrity of a structure, component, or material. The Engine Titanium Consortium (ETC) was established in 1993 to respond to recommendations made by the Federal Aviation Administration (FAA) Titanium Rotating Components Review Team (TRCRT) for improvements in inspection of engine titanium. Several recent accomplishments of the ETC are detailed in this paper. The objective of the Engine Titanium Consortium is to provide the FAAand the manufacturers with reliable and costeffective new methods and/or improvements in mature methods for detecting cracks, inclusions, and imperfections in titanium. The consortium consists of a team of researchers from academia and industry-namely, Iowa State University, Allied Signal Propulsion Engines, General Electric Aircraft Engines, and Pratt & Whitney Engines-who work together to develop program priorities, organize a program plan, conduct the research, and implement the solutions. The true advantage of the consortium approach is that it brings together the research talents of academia and the engineering talents of industry to tackle a technology-base problem. In bringing industrial competitors together, the consortium ensures that the research results, which have safety implications and result from FAA funds, are shared and become part of the public domain.

  10. Investigation of the misfueling of reciprocating piston aircraft engines

    NASA Technical Reports Server (NTRS)

    Scott, J. Holland, Jr.

    1988-01-01

    The Aircraft Misfueling Detection Project was developed by the Goddard Space Flight Center/Wallops Flight Facility at Wallops Island, Virginia. Its purpose was to investigate the misfueling of reciprocating piston aircraft engines by the inadvertent introduction of jet fuel in lieu of or as a contaminant of aviation gasoline. The final objective was the development of a device(s) that will satisfactorily detect misfueling and provide pilots with sufficient warning to avoid injury, fatality, or equipment damage. Two devices have been developed and successfully tested: one, a small contamination detection kit, for use by the pilot, and a second, more sensitive, modified gas chromatograph for use by the fixed-base operator. The gas chromatograph, in addition to providing excellent quality control of the fixed-base operator's fuel handling, is a very good backup for the detection kit in the event it produces negative results. Design parameters were developed to the extent that they may be applied easily to commercial production by the aircraft industry.

  11. Structural Optimization Methodology for Rotating Disks of Aircraft Engines

    NASA Technical Reports Server (NTRS)

    Armand, Sasan C.

    1995-01-01

    In support of the preliminary evaluation of various engine technologies, a methodology has been developed for structurally designing the rotating disks of an aircraft engine. The structural design methodology, along with a previously derived methodology for predicting low-cycle fatigue life, was implemented in a computer program. An interface computer program was also developed that gathers the required data from a flowpath analysis program (WATE) being used at NASA Lewis. The computer program developed for this study requires minimum interaction with the user, thus allowing engineers with varying backgrounds in aeropropulsion to successfully execute it. The stress analysis portion of the methodology and the computer program were verified by employing the finite element analysis method. The 10th- stage, high-pressure-compressor disk of the Energy Efficient Engine Program (E3) engine was used to verify the stress analysis; the differences between the stresses and displacements obtained from the computer program developed for this study and from the finite element analysis were all below 3 percent for the problem solved. The computer program developed for this study was employed to structurally optimize the rotating disks of the E3 high-pressure compressor. The rotating disks designed by the computer program in this study were approximately 26 percent lighter than calculated from the E3 drawings. The methodology is presented herein.

  12. Application of superalloy powder metallurgy for aircraft engines

    NASA Technical Reports Server (NTRS)

    Dreshfield, R. L.; Miner, R. V., Jr.

    1980-01-01

    In the last decade, Government/Industry programs have advanced powder metallurgy-near-net-shape technology to permit the use of hot isostatic pressed (HIP) turbine disks in the commercial aircraft fleet. These disks offer a 30% savings of input weight and an 8% savings in cost compared in cast-and-wrought disks. Similar savings were demonstrated for other rotating engine components. A compressor rotor fabricated from hot-die-forged-HIP superalloy billets revealed input weight savings of 54% and cost savings of 35% compared to cast-and-wrought parts. Engine components can be produced from compositions such as Rene 95 and Astroloy by conventional casting and forging, by forging of HIP powder billets, or by direct consolidation of powder by HIP. However, each process produces differences in microstructure or introduces different defects in the parts. As a result, their mechanical properties are not necessarily identical. Acceptance methods should be developed which recognize and account for the differences.

  13. Commercial Aircraft Maintenance Experience Relating to Engine External Hardware

    NASA Technical Reports Server (NTRS)

    Soditus, Sharon M.

    2006-01-01

    Airlines are extremely sensitive to the amount of dollars spent on maintaining the external engine hardware in the field. Analysis reveals that many problems revolve around a central issue, reliability. Fuel and oil leakage due to seal failure and electrical fault messages due to wire harness failures play a major role in aircraft delays and cancellations (D&C's) and scheduled maintenance. Correcting these items on the line requires a large investment of engineering resources and manpower after the fact. The smartest and most cost effective philosophy is to build the best hardware the first time. The only way to do that is to completely understand and model the operating environment, study the field experience of similar designs and to perform extensive testing.

  14. Simulation of Aircraft Engine Blade-Out Structural Dynamics. Revised

    NASA Technical Reports Server (NTRS)

    Lawrence, Charles; Carney, Kelly; Gallardo, Vicente

    2001-01-01

    A primary concern of aircraft structure designers is the accurate simulation of the blade-out event and the subsequent windmilling of the engine. Reliable simulations of the blade-out event are required to insure structural integrity during flight as well as to guarantee successful blade-out certification testing. The system simulation includes the lost blade loadings and the interactions between the rotating turbomachinery and the remaining aircraft structural components. General-purpose finite element structural analysis codes such as MSC NASTRAN are typically used and special provisions are made to include transient effects from the blade loss and rotational effects resulting from the engine's turbomachinery. The present study provides the equations of motion for rotordynamic response including the effect of spooldown speed and rotor unbalance and examines the effects of these terms on a cantilevered rotor. The effect of spooldown speed is found to be greater with increasing spooldown rate. The parametric term resulting from the mass unbalance has a more significant effect on the rotordynamic response than does the spooldown term. The parametric term affects both the peak amplitudes as well as the resonant frequencies of the rotor.

  15. Simulation of Aircraft Engine Blade-Out Structural Dynamics

    NASA Technical Reports Server (NTRS)

    Lawrence, Charles; Carney, Kelly; Gallardo, Vicente

    2001-01-01

    A primary concern of aircraft structure designers is the accurate simulation of the blade-out event and the subsequent windmilling of the engine. Reliable simulations of the blade-out event are required to insure structural integrity during flight as well as to guarantee successful blade-out certification testing. The system simulation includes the lost blade loadings and the interactions between the rotating turbomachinery and the remaining aircraft structural components. General-purpose finite element structural analysis codes such as MSC NASTRAN are typically used and special provisions are made to include transient effects from the blade loss and rotational effects resulting from the engine's turbomachinery. The present study provides the equations of motion for rotordynamic response including the effect of spooldown speed and rotor unbalance and examines the effects of these terms on a cantilevered rotor. The effect of spooldown speed is found to be greater with increasing spooldown rate. The parametric term resulting from the mass unbalance has a more significant effect on the rotordynamic response than does the spooldown term. The parametric term affects both the peak amplitudes as well as the resonant frequencies of the rotor.

  16. Outdoor test stand performance of a convertible engine with variable inlet guide vanes for advanced rotorcraft propulsion

    NASA Technical Reports Server (NTRS)

    Mcardle, Jack G.

    1986-01-01

    A variable inlet guide van (VIGV) type convertible engine that could be used to power future high-speed rotorcraft was tested on an outdoor stand. The engine ran stably and smoothly in the turbofan, turboshaft, and dual (combined fan and shaft) power modes. In the turbofan mode with the VIGV open fuel consumption was comparable to that of a conventional turbofan engine. In the turboshaft mode with the VIGV closed fuel consumption was higher than that of present turboshaft engines because power was wasted in churning fan-tip airflow. In dynamic performance tests with a specially built digital engine control and using a waterbrake dynamometer for shaft load, the engine responded effectively to large steps in thrust command and shaft torque. Previous mission analyses of a conceptual X-wing rotorcraft capable of 400-knot cruise speed were revised to account for more fan-tip churning power loss than was originally estimated. The new calculations confirm that using convertible engines rather than separate lift and cruise engines would result in a smaller, lighter craft with lower fuel use and direct operating cost.

  17. Comparison of predicted engine core noise with current and proposed aircraft noise certification requirements

    NASA Technical Reports Server (NTRS)

    Vonglahn, U. H.; Groesbeck, D. E.

    1981-01-01

    Predicted engine core noise levels are compared with measured total aircraft noise levels and with current and proposed federal noise certification requirements. Comparisons are made at the FAR-36 measuring stations and include consideration of both full- and cutback-power operation at takeoff. In general, core noise provides a barrier to achieving proposed EPA stage 5 noise levels for all types of aircraft. More specifically, core noise levels will limit further reductions in aircraft noise levels for current widebody commercial aircraft.

  18. Interface of an uncoupled boundary layer algorithm with an inviscid core flow algorithm for unsteady supersonic engine inlets

    NASA Technical Reports Server (NTRS)

    Darling, Douglas; Sakowski, Barbara

    1992-01-01

    An uncoupled boundary layer algorithm was combined with an inviscid core flow algorithm to model flows within supersonic engine inlets. The inviscid flow algorithm that was used was the LArge Perturbation INlet Code (LAPIN). The boundary layer and inviscid core flow algorithms were formulated in different manners. The boundary layer algorithm was two dimensional and solved in nonconservation form, while the core flow algorithm was one dimensional and solved in conservation form. In order to interface the two codes, the following modifications were important. The coordinate system was set up to maintain the parabolic nature of the boundary layer algorithm while approaching the one dimensional core flow solution far from a wall. The pressure gradient used in the boundary layer equation was calculated using the core flow values and the boundary layer equations, so the boundary layer solution smoothly approached the core flow values far from the wall. Flaring was used for the advection terms perpendicular to the core flow to maintain the stability of the algorithm. With these modifications, the combined viscous/inviscid algorithm matched well experimental observations of pressure distributions with a supersonic inlet.

  19. Interface of an uncoupled boundary layer algorithm with an inviscid core flow algorithm for unsteady supersonic engine inlets

    NASA Technical Reports Server (NTRS)

    Darling, Douglas; Sakowski, Barbara

    1992-01-01

    An uncoupled boundary layer algorithm was combined with an inviscid core flow algorithm to model flows within supersonic engine inlets. The inviscid flow algorithm that was used was the LArge Perturbation INlet Code (LAPIN). The boundary layer and inviscid core flow algorithms were formulated in different manners. The boundary layer algorithm was two dimensional and solved in nonconservation form, while the core flow algorithm was one dimensional and solved in conservation form. In order to interface the two codes, the following modifications were important. The coordinate system was set up to maintain the parabolic nature of the boundary layer algorithm while approaching the one dimensional core flow solution far from a wall. The pressure gradient used in the boundary layer equation was calculated using the core flow values and the boundary layer equations, so the boundary layer solution smoothly approached the core flow values far from the wall. Flaring was used for the advection terms perpendicular to the core flow to maintain the stability of the algorithm. With these modifications, the combined viscous/inviscid algorithm matched well with experimental observations of pressure distributions with a supersonic inlet.

  20. Failure Investigation of WB-57 Aircraft Engine Cowling

    NASA Technical Reports Server (NTRS)

    Martinez, J. E.; Gafka, T.; Figert, J.

    2014-01-01

    The NASA Johnson Space Center (JSC) in Houston, Texas is the home of the NASA WB-57 High Altitude Research Program. Three fully operational WB-57 aircraft are based near JSC at Ellington Field. The aircraft have been flying research missions since the early 1960's, and continue to be an asset to the scientific community with professional, reliable, customer-oriented service designed to meet all scientific objectives. The NASA WB-57 Program provides unique, high-altitude airborne platforms to US Government agencies, academic institutions, and commercial customers in order to support scientific research and advanced technology development and testing at locations around the world. Mission examples include atmospheric and earth science, ground mapping, cosmic dust collection, rocket launch support, and test bed operations for future airborne or spaceborne systems. During the return from a 6 hour flight, at 30,000 feet, in the clean configuration, traveling at 175 knots indicated airspeed, in un-accelerated flight with the auto pilot engaged, in calm air, the 2-man crew heard a mechanical bang and felt a slight shudder followed by a few seconds of high frequency vibration. The crew did not notice any other abnormalities leading up to, or for the remaining 1 hour of flight and made an uneventful landing. Upon taxi into the chocks, the recovery ground crew noticed the high frequency long wire antenna had become disconnected from the vertical stabilizer and was trailing over the left inboard wing, and that the left engine upper center removable cowling panel was missing, with noticeable damage to the left engine inboard cowling fixed structure. The missing cowling panel was never recovered. Each engine cowling panel is attached to the engine nacelle using six bushings made of 17-4 PH steel. The cylinder portions of four of the six bushings were found still attached to the aircraft (Fig 1). The other two bushings were lost with the panel. The other four bushings exhibited

  1. Inlet Flow Control and Prediction Technologies for Embedded Propulsion Systems

    NASA Technical Reports Server (NTRS)

    McMillan, Michelle L.; Mackie, Scott A.; Gissen, Abe; Vukasinovic, Bojan; Lakebrink, Matthew T.; Glezer, Ari; Mani, Mori; Mace, James L.

    2011-01-01

    Fail-safe, hybrid, flow control (HFC) is a promising technology for meeting high-speed cruise efficiency, low-noise signature, and reduced fuel-burn goals for future, Hybrid-Wing-Body (HWB) aircraft with embedded engines. This report details the development of HFC technology that enables improved inlet performance in HWB vehicles with highly integrated inlets and embedded engines without adversely affecting vehicle performance. In addition, new test techniques for evaluating Boundary-Layer-Ingesting (BLI)-inlet flow-control technologies developed and demonstrated through this program are documented, including the ability to generate a BLI-like inlet-entrance flow in a direct-connect, wind-tunnel facility, as well as, the use of D-optimal, statistically designed experiments to optimize test efficiency and enable interpretation of results. Validated improvements in numerical analysis tools and methods accomplished through this program are also documented, including Reynolds-Averaged Navier-Stokes CFD simulations of steady-state flow physics for baseline, BLI-inlet diffuser flow, as well as, that created by flow-control devices. Finally, numerical methods were employed in a ground-breaking attempt to directly simulate dynamic distortion. The advances in inlet technologies and prediction tools will help to meet and exceed "N+2" project goals for future HWB aircraft.

  2. Energy efficient engine program contributions to aircraft fuel conservation

    NASA Technical Reports Server (NTRS)

    Batterton, P. G.

    1984-01-01

    Significant advances in high bypass turbofan technologies that enhance fuel efficiency have been demonstrated in the NASA Energy Efficient Engine Program. This highly successful second propulsion element of the NASA Aircraft Energy Efficiency Program included major contract efforts with both General Electric and Pratt & Whitney. Major results of these efforts will be presented including highlights from the NASA/General Electric E3 research turbofan engine test. Direct application of all the E3 technologies could result in fuel savings of over 18% compared to the CF6-50 and JT9D-7. Application of the E3 technologies to new and derivative engines such as the CF6-80C and PW 2037, as well as others, will be discussed. Significant portions of the fuel savings benefit for these new products can be directly related to the E3 technology program. Finally, results of a study looking at far term advanced turbofan engines will be briefly described. The study shows that substantial additional fuel savings over E3 are possible with additional turbofan technology programs.

  3. Proposed Rule and Related Materials for Control of Emissions of Air Pollution From Nonroad Diesel Engines Control of Air Pollution From Aircraft and Aircraft Engines; Proposed Emission Standards and Test Procedures

    EPA Pesticide Factsheets

    Proposed Rule and Related Materials for Control of Emissions of Air Pollution From Nonroad Diesel Engines Control of Air Pollution From Aircraft and Aircraft Engines; Proposed Emission Standards and Test Procedures

  4. 75 FR 28504 - Airworthiness Directives; Various Aircraft Equipped With Rotax Aircraft Engines 912 A Series Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-21

    ...) Perform a leak check as follows: (i) Clean the crankcase surface to remove any oil. (ii) Warm up the engine to a minimum oil temperature of 50 degrees C (120 degrees F). Information about warming up the... crankcase assembly S/N up to and including S/N 27811, certificated in any category: Type certificate...

  5. Dynamic response of a Mach 2.5 axisymmetric inlet and turbojet engine with a poppet-value controlled inlet stability bypass system when subjected to internal and external airflow transients

    NASA Technical Reports Server (NTRS)

    Sanders, B. W.

    1980-01-01

    The throat of a Mach 2.5 inlet that was attached to a turbojet engine was fitted with a poppet-valve-controlled stability bypass system that was designed to provide a large, stable airflow range. Propulsion system response and stability bypass performance were determined for several transient airflow disturbances, both internal and external. Internal airflow disturbances included reductions in overboard bypass airflow, power lever angle, and primary-nozzle area as well as compressor stall. For reference, data are also included for a conventional, fixed-exit bleed system. The poppet valves greatly increased inlet stability and had no adverse effects on propulsion system performance. Limited unstarted-inlet bleed performance data are presented.

  6. Fatigue Lifetime Assessment of Aircraft Engine Disc via Multi-source Information Fusion

    NASA Astrophysics Data System (ADS)

    Huang, Hong-Zhong; Cui, Ping-Liang; Peng, Weiwen; Gao, Hui-Ying; Wang, Hai-Kun

    2014-06-01

    Fatigue lifetime assessment for aircraft engine discs is an important issue for the operation and health management of aircraft engines. Due to the lack of field test data, traditional methods can hardly meet the requirements of fatigue lifetime assessment of aircraft engine discs. By combining a multi-source information fusion method with a Bayesian inference technique, this paper develops a practical approach for fatigue lifetime assessment of aircraft engine discs. Subjective information and historical data are combined coherently with the sparse test data to generate a credible fatigue lifetime assessment of aircraft engine discs. Methods for quantifying subjective information, checking different experts' information, and fusing multiple prior distributions are presented to facilitate the implementation of fatigue lifetime assessment. An illustrative example is presented to demonstrate the procedures and the implication of the proposed method.

  7. Design study of a dual-cycle turbofan-ramjet engine for a hypersonic aircraft

    NASA Technical Reports Server (NTRS)

    Zumwalt, G. W.; Suwanprasert, S.

    1983-01-01

    Computer modelling was used with two different designs of an advanced turbofan-ramjet in order to derive performance predictions. The engine would enable an aircraft to take-off, accelerate to Mach 5.0, and climb to 90,000 ft. The two concepts included a turbofan with a ramjet annularly wrapped around it and a side-by-side configuration with the ramjet having a rectangular shape and mounted alongside the turbofan. The studies were performed to model weight, length, fuel efficiency, and the requirements of the thrust/drag ratio to exceed unity over the entire flight path. LH2 would be used for fuel and to regeneratively cool the combustion chamber. Turbofan operation with and without afterburner and with and without the ramjet inlet open were examined, as were variable areas for the burners. A side-by-side configuration displayed the best performance predictions, with a ramjet mass flow being 75 percent that of the turbofan and maximum temperatures being equal.

  8. An integrated systems engineering approach to aircraft design

    NASA Astrophysics Data System (ADS)

    Price, M.; Raghunathan, S.; Curran, R.

    2006-06-01

    The challenge in Aerospace Engineering, in the next two decades as set by Vision 2020, is to meet the targets of reduction of nitric oxide emission by 80%, carbon monoxide and carbon dioxide both by 50%, reduce noise by 50% and of course with reduced cost and improved safety. All this must be achieved with expected increase in capacity and demand. Such a challenge has to be in a background where the understanding of physics of flight has changed very little over the years and where industrial growth is driven primarily by cost rather than new technology. The way forward to meet the challenges is to introduce innovative technologies and develop an integrated, effective and efficient process for the life cycle design of aircraft, known as systems engineering (SE). SE is a holistic approach to a product that comprises several components. Customer specifications, conceptual design, risk analysis, functional analysis and architecture, physical architecture, design analysis and synthesis, and trade studies and optimisation, manufacturing, testing validation and verification, delivery, life cycle cost and management. Further, it involves interaction between traditional disciplines such as Aerodynamics, Structures and Flight Mechanics with people- and process-oriented disciplines such as Management, Manufacturing, and Technology Transfer. SE has become the state-of-the-art methodology for organising and managing aerospace production. However, like many well founded methodologies, it is more difficult to embody the core principles into formalised models and tools. The key contribution of the paper will be to review this formalisation and to present the very latest knowledge and technology that facilitates SE theory. Typically, research into SE provides a deeper understanding of the core principles and interactions, and helps one to appreciate the required technical architecture for fully exploiting it as a process, rather than a series of events. There are major issues as

  9. Static and transient performance of YF-102 engine with up to 14 percent core airbleed for the quiet short-haul research aircraft

    NASA Technical Reports Server (NTRS)

    Mcardle, J. G.; Homyak, L.; Moore, A. S.

    1980-01-01

    An outdoor static test stand was used to measure the steady-state and transient performance of the YF-102 turbofan engine with core airbleed. The test configuration included a bellmouth inlet and a confluent-flow exhaust system similar in size to the quiet short-haul research aircraft (QSRA) exhaust system. For the steady-state tests, the engine operated satisfactorily with core bleed up to 14 percent of the core inlet flow. For the transient tests the engine accelerated and decelerated satisfactorily with no core bleed and with core bleed up to 11 percent of the core inlet flow (maximum tested). For some of the tests the core-bleed flow rate was scheduled to vary with fan discharge pressure, to simulate the QSRA bleed requirements. No stability, surge, stall, overtemperature, combustor flameout, or other operating problems were encountered in any of the tests. Steady-state and transient engine performance data are presented in graphs, and fuel-control trajectories for typical transient tests are shown.

  10. Cooling Characteristics of a Pratt and Whitney R-2800 Engine Installed in an NACA Short-nose High-inlet-velocity Cowling

    NASA Technical Reports Server (NTRS)

    Corson, Blake W.; McLellan, Charles H.

    1944-01-01

    An investigation was made of the cooling characteristics of a P and W R-2800 engine with NACA short-nose high inlet-velocity cowling. The internal aerodynamics of the cowling were studied for ranges of propeller-advance ratio and inlet-velocity ratio obtained by deflection of cowling flaps. Tests included variations of engine power, fuel/air ratio and cooling-air pressure drop. Engine cooling data are presented in the form of cooling correlation curves, and an example for calculation of cooling requirements in flight is included.

  11. Aircraft Turbine Engine Monitoring Systems: Overview and Lessons Learned from Six Case Studies

    DTIC Science & Technology

    1979-05-01

    engines of both groups. EHMS (T-38 / J85 ) ACTIVITY OUTCOMES JULY 󈨐 - MAY 󈨑 INSIRUMENTED ENGINES CONTROL ENGINES NUMBER OF ENGINES 26 26 TOTAL...Kreviews the experience gained from several aircraft turbine engine monitoring systems used over the last decade and a half and examines the...the supporting research. -,Two different approaches to engine monitoring have evolved in attempts to achieve the goals of improved engine operations

  12. A design strategy for the use of vortex generators to manage inlet-engine distortion using computational fluid dynamics

    NASA Technical Reports Server (NTRS)

    Anderson, Bernhard H.; Levy, Ralph

    1991-01-01

    A reduced Navier-Stokes solution technique was successfully used to design vortex generator installations for the purpose of minimizing engine face distortion by restructuring the development of secondary flow that is induced in typical 3-D curved inlet ducts. The results indicate that there exists an optimum axial location for this installation of corotating vortex generators, and within this configuration, there exists a maximum spacing between generator blades above which the engine face distortion increases rapidly. Installed vortex generator performance, as measured by engine face circumferential distortion descriptors, is sensitive to Reynolds number and thereby the generator scale, i.e., the ratio of generator blade height to local boundary layer thickness. Installations of corotating vortex generators work well in terms of minimizing engine face distortion within a limited range of generator scales. Hence, the design of vortex generator installations is a point design, and all other conditions are off design. In general, the loss levels associated with a properly designed vortex generator installation are very small; thus, they represent a very good method to manage engine face distortion. This study also showed that the vortex strength, generator scale, and secondary flow field structure have a complicated and interrelated influence over engine face distortion, over and above the influence of the initial arrangement of generators.

  13. Real-time measurements of jet aircraft engine exhaust.

    PubMed

    Rogers, Fred; Arnott, Pat; Zielinska, Barbara; Sagebiel, John; Kelly, Kerry E; Wagner, David; Lighty, JoAnn S; Sarofim, Adel F

    2005-05-01

    Particulate-phase exhaust properties from two different types of ground-based jet aircraft engines--high-thrust and turboshaft--were studied with real-time instruments on a portable pallet and additional time-integrated sampling devices. The real-time instruments successfully characterized rapidly changing particulate mass, light absorption, and polycyclic aromatic hydrocarbon (PAH) content. The integrated measurements included particulate-size distributions, PAH, and carbon concentrations for an entire test run (i.e., "run-integrated" measurements). In all cases, the particle-size distributions showed single modes peaking at 20-40nm diameter. Measurements of exhaust from high-thrust F404 engines showed relatively low-light absorption compared with exhaust from a turboshaft engine. Particulate-phase PAH measurements generally varied in phase with both net particulate mass and with light-absorbing particulate concentrations. Unexplained response behavior sometimes occurred with the real-time PAH analyzer, although on average the real-time and integrated PAH methods agreed within the same order of magnitude found in earlier investigations.

  14. Performance of Several Combustion Chambers Designed for Aircraft Oil Engines

    NASA Technical Reports Server (NTRS)

    Joachim, William F; Kemper, Carlton

    1928-01-01

    Several investigations have been made on single-cylinder test engines to determine the performance characteristics of four types of combustion chambers designed for aircraft oil engines. Two of the combustion chambers studied were bulb-type precombustion chambers, the connecting orifice of one having been designed to produce high turbulence by tangential air flow in both the precombustion chamber and the cylinder. The other two were integral combustion chambers, one being dome-shaped and the other pent-roof shaped. The injection systems used included cam and eccentric driven fuel pumps, and diaphragm and spring-loaded fuel-injection valves. A diaphragm type maximum cylinder pressure indicator was used in part of these investigations with which the cylinder pressures were controlled to definite valves. The performance of the engines when equipped with each of the combustion chambers is discussed. The best performance for the tests reported was obtained with a bulb-type combustion chamber designed to give a high degree of turbulence within the bulb and cylinder. (author)

  15. ADAM: An Axisymmetric Duct Aeroacoustic Modeling system. [aircraft turbofan engines

    NASA Technical Reports Server (NTRS)

    Abrahamson, A. L.

    1983-01-01

    An interconnected system of computer programs for analyzing the propagation and attenuation of sound in aeroengine ducts containing realistic compressible subsonic mean flows, ADAM was developed primarily for research directed towards the reduction of noise emitted from turbofan aircraft engines. The two basic components are a streamtube curvature program for determination of the mean flow, and a finite element code for solution of the acoustic propagation problem. The system, which has been specifically tailored for ease of use, is presently installed at NASA Langley Reseach Center on a Control Data Cyber 175 Computer under the NOS Operating system employing a Tektronix terminal for interactive graphics. The scope and organization of the ADAM system is described. A users guide, examples of input data, and results for selected cases are included.

  16. Aircraft engine with inter-turbine engine frame supported counter rotating low pressure turbine rotors

    NASA Technical Reports Server (NTRS)

    Seda, Jorge F. (Inventor); Dunbar, Lawrence W. (Inventor); Gliebe, Philip R. (Inventor); Szucs, Peter N. (Inventor); Brauer, John C. (Inventor); Johnson, James E. (Inventor); Moniz, Thomas (Inventor); Steinmetz, Gregory T. (Inventor)

    2003-01-01

    An aircraft gas turbine engine assembly includes an inter-turbine frame axially located between high and low pressure turbines. Low pressure turbine has counter rotating low pressure inner and outer rotors with low pressure inner and outer shafts which are at least in part rotatably disposed co-axially within a high pressure rotor. Inter-turbine frame includes radially spaced apart radially outer first and inner second structural rings disposed co-axially about a centerline and connected by a plurality of circumferentially spaced apart struts. Forward and aft sump members having forward and aft central bores are fixedly joined to axially spaced apart forward and aft portions of the inter-turbine frame. Low pressure inner and outer rotors are rotatably supported by a second turbine frame bearing mounted in aft central bore of aft sump member. A mount for connecting the engine to an aircraft is located on first structural ring.

  17. Evaluation and application of the Baldwin-Lomax turbulence model in two-dimensional, unsteady, compressible boundary layers with and without separation in engine inlets

    NASA Technical Reports Server (NTRS)

    Sakowski, Barbara; Darling, Douglas; Roach, Robert L.; Vandewall, Allan

    1992-01-01

    There is a practical need to model high speed flows that exist in jet engine inlets. The boundary layers that form in these inlets may be turbulent or laminar and either separated or attached. Also, unsteady supersonic inlets may be subject to frequent changes in operating conditions. Some changes in the operating conditions of the inlets may include varying the inlet geometry, bleeds and bypasses, and rotating or translating the centerbody. In addition, the inlet may be either started or unstarted. Therefore, a CFD code, used to model these inlets, may have to run for several different cases. Also, since the flow conditions through an unsteady inlet may be continually fluctuating, the CFD code which models these flows may have to be run over many time steps. Therefore, it would be beneficial that the code run quickly. Many turbulence models, however, are cumbersome to implement and require a lot of computer time to run, since they add to the number of differential equations to be solved to model a flow. The Baldwin-Lomax turbulence model is a popular model. It is an algebraic, eddy viscosity model. The Baldwin-Lomax model is used in many CFD codes because it is quick and easy to implement. In this paper, we will discuss implementing the Baldwin-Lomax turbulence model for both steady and unsteady compressible flows. In addition, these flows may be either separated or attached. In order to apply this turbulence model to flows which may be subjected to these conditions, certain modifications should be made to the original Baldwin-Lomax model. We will discuss these modifications and determine whether the Baldwin-Lomax model is a viable turbulence model that produces reasonably accurate results for high speed flows that can be found in engine inlets.

  18. Adaptive Failure Compensation for Aircraft Flight Control Using Engine Differentials: Regulation

    NASA Technical Reports Server (NTRS)

    Yu, Liu; Xidong, Tang; Gang, Tao; Joshi, Suresh M.

    2005-01-01

    The problem of using engine thrust differentials to compensate for rudder and aileron failures in aircraft flight control is addressed in this paper in a new framework. A nonlinear aircraft model that incorporates engine di erentials in the dynamic equations is employed and linearized to describe the aircraft s longitudinal and lateral motion. In this model two engine thrusts of an aircraft can be adjusted independently so as to provide the control flexibility for rudder or aileron failure compensation. A direct adaptive compensation scheme for asymptotic regulation is developed to handle uncertain actuator failures in the linearized system. A design condition is specified to characterize the system redundancy needed for failure compensation. The adaptive regulation control scheme is applied to the linearized model of a large transport aircraft in which the longitudinal and lateral motions are coupled as the result of using engine thrust differentials. Simulation results are presented to demonstrate the effectiveness of the adaptive compensation scheme.

  19. Role of structural noise in aircraft pressure cockpit from vibration action of new-generation engines

    NASA Astrophysics Data System (ADS)

    Baklanov, V. S.

    2016-07-01

    The evolution of new-generation aircraft engines is transitioning from a bypass ratio of 4-6 to an increased ratio of 8-12. This is leading to substantial broadening of the vibration spectrum of engines with a shift to the low-frequency range due to decreased rotation speed of the fan rotor, in turn requiring new solutions to decrease structural noise from engine vibrations to ensure comfort in the cockpits and cabins of aircraft.

  20. Inlet contour and flow effects on radiation

    NASA Technical Reports Server (NTRS)

    Ville, J. M.; Silcox, R. J.

    1980-01-01

    An experimental investigation of sound radiation from inlets with different contours with and without flow is being conducted to study the possibility of reducing noise radiated by aircraft engines. For each inlet configuration, complex directivity patterns and complex pressure reflection coefficients are measured as a function of a single space-time structure of the wave (up to a frequency of 4000Hz and an azimuthal wave number 6) and of flow velocity (up to Mach number 0.4) in a cylindrical duct located downstream the inlet. Experimental results of radiation from an unflanged duct are compared with theory. Effect of inlet contour and flow are deduced by comparing respectively unflanged duct and bellmouth measurements and, no flow and flow measurements with the bellmouth. Results are presented which indicate that the contour effect is significant near the cut-on frequency of a mode and emphasize the necessity for taking into account the inlet geometry in a radiation prediction. These results show also that internal flow has a weak effect on the amplitude of the directivity pattern

  1. Analysis of Buzz in a Supersonic Inlet

    NASA Technical Reports Server (NTRS)

    Chima, Rodrick V.

    2012-01-01

    A dual-stream, low-boom supersonic inlet designed for use on a small, Mach 1.6 aircraft was tested experimentally in the 8- by 6-Foot Supersonic Wind Tunnel (SWT) at the NASA Glenn Research Center (GRC). The tests showed that the inlet had good recovery and stable operation over large mass flow range. The inlet went into buzz at mass flows well below that needed for engine operation, and the experiments generated a wealth of data during buzz. High frequency response pressure measurements and high-speed schlieren videos were recorded for many buzz events. The objective of the present work was to use computational fluid dynamics (CFD) to predict some of the experimental data taken during buzz, compare those predictions to the experimental data, and to use both datasets to explain the physics of the buzz cycle. The calculations were done with the Wind-US CFD code using a second-order time-accurate differencing scheme and the SST turbulence model. Computed Mach number contours were compared with schlieren images, and ensemble-averaged unsteady pressures were compared to data. The results showed that the buzz cycle consisted partly of spike buzz, an unsteady oscillation of the main shock at the spike tip while the inlet pressure dropped, and partly of choked flow while the inlet repressurized. Most of the results could be explained by theory proposed by Dailey in 1954, but did not support commonly used acoustic resonance explanations.

  2. STUDY PROGRAM FOR TURBO-COOLER FOR PRODUCING ENGINE COOLING AIR.

    DTIC Science & Technology

    VANES , STAGNATION POINT, DECELERATION, ACCELERATION, SUPERSONIC DIFFUSERS, TURBINE BLADES , EVAPOTRANSPIRATION, LIQUID COOLED, HEAT TRANSFER, GAS BEARINGS, SEALS...HYPERSONIC AIRCRAFT , COOLING + VENTILATING EQUIPMENT), (*GAS TURBINES , COOLING + VENTILATING EQUIPMENT), HYPERSONIC FLOW, AIR COOLED, AIRCRAFT ... ENGINES , FEASIBILITY STUDIES, PRESSURE, SUPERSONIC CHARACTERISTICS, DESIGN, HEAT EXCHANGERS, COOLING (U) AXIAL FLOW TURBINES , DUCT INLETS, INLET GUIDE

  3. Modern design methodology and problems in training aircraft engineers

    NASA Technical Reports Server (NTRS)

    Liseitsev, N. K.

    1989-01-01

    A brief report on the problem of modern aircraft specialist education is presented that is devoted to the content and methods of teaching a course in General Aircraft Design in the Moscow Aviation Institute.

  4. Boundary layer effects on liners for aircraft engines

    NASA Astrophysics Data System (ADS)

    Gabard, Gwénaël

    2016-10-01

    The performance of acoustic treatments installed on aircraft engines is strongly influenced by the boundary layer of the grazing flow on the surface of the liner. The parametric study presented in this paper illustrates the extent of this effect and identifies when it is significant. The acoustic modes of a circular duct with flow are calculated using a finite difference method. The parameters are representative of the flow conditions, liners and sound fields found in current turbofan engines. Both the intake and bypass ducts are considered. Results show that there is a complex interplay between the boundary layer thickness, the direction of propagation and the liner impedance and that the boundary layer can have a strong impact on liner performance for typical configurations (including changes of the order of 30 dB on the attenuation of modes associated with tonal fan noise). A modified impedance condition including the effect of a small but finite boundary layer thickness is considered and compared to the standard Myers condition based on an infinitely thin boundary layer. We show how this impedance condition can be implemented in a mode calculation method by introducing auxiliary variables. This condition is able to capture the trends associated with the boundary layer effects and in most cases provides improved predictions of liner performance.

  5. Analysis of the reverse jet influence on particle ingestion at the engine inlet

    NASA Astrophysics Data System (ADS)

    Krasheninnikov, S. Yu.; Pudovikov, D. E.

    2015-06-01

    The reverse mode of an operating near-ground jet engine is considered. The air flow and particle trajectories under the engine intake are calculated. On the base of numerical and theoretical analysis of the air flow and particle trajectories, some conclusions about reducing the probability of transportation of large particles to the engine are drawn.

  6. Advanced prediction technique for the low speed aerodynamics of V/STOL aircraft. Volume 2: User's manual

    NASA Technical Reports Server (NTRS)

    Beatty, T. D.; Worthey, M. K.

    1984-01-01

    A computerized prediction method known as the Vought V/STOL Aircraft Propulsive Effects computer program (VAPE) for propulsive induced forces and moments in transition and Short TakeOff and Landing (STOL) flight is improved and evaluated. The VAPE program is capable of evaluating: (1) effects of relative wind about an aircraft, (2) effects of propulsive lift jet entrainment, vorticity and flow blockage, (3) effects of engine inlet flow on the aircraft flow field, (4) engine inlet forces and moments including inlet separation, (5) ground effects in the STOL region of flight, and (6) viscous effects on lifting surfaces.

  7. Analysis of thrust augmentation of turbojet engines by water injection at compressor inlet including charts for calculating compression processes with water injection

    NASA Technical Reports Server (NTRS)

    Wilcox, E Clinton; Trout, Arthur M

    1951-01-01

    A psychrometric chart having total pressure (sum of partial pressures of air and water vapor) as a variable, a Mollier diagram for air saturated with water vapor, and charts showing the thermodynamic properties of various air-water vapor and exhaust gas-water vapor mixtures are presented as aids in calculating the thrust augmentation of a turbojet engine resulting from the injection of water at the compressor inlet. Curves are presented that show the theoretical performance of the augmentation method for various amounts of water injected and the effects of varying flight Mach number, altitude, ambient-air temperature, ambient relative humidity, compressor pressure ratio, and inlet-diffuser efficiency. Numerical examples, illustrating the use of the psychrometric chart and the Mollier diagram in calculating both compressor-inlet and compressor-outlet conditions when water is injected at the compressor inlet, are presented.

  8. Small Engine Technology (SET) Task 24 Business and Regional Aircraft System Studies

    NASA Technical Reports Server (NTRS)

    Lieber, Lysbeth

    2003-01-01

    This final report has been prepared by Honeywell Engines & Systems, Phoenix, Arizona, a unit of Honeywell International Inc., documenting work performed during the period June 1999 through December 1999 for the National Aeronautics and Space Administration (NASA) Glenn Research Center, Cleveland, Ohio, under the Small Engine Technology (SET) Program, Contract No. NAS3-27483, Task Order 24, Business and Regional Aircraft System Studies. The work performed under SET Task 24 consisted of evaluating the noise reduction benefits compared to the baseline noise levels of representative 1992 technology aircraft, obtained by applying different combinations of noise reduction technologies to five business and regional aircraft configurations. This report focuses on the selection of the aircraft configurations and noise reduction technologies, the prediction of noise levels for those aircraft, and the comparison of the noise levels with those of the baseline aircraft.

  9. Data Fusion for Enhanced Aircraft Engine Prognostics and Health Management

    NASA Technical Reports Server (NTRS)

    Volponi, Al

    2005-01-01

    Aircraft gas-turbine engine data is available from a variety of sources, including on-board sensor measurements, maintenance histories, and component models. An ultimate goal of Propulsion Health Management (PHM) is to maximize the amount of meaningful information that can be extracted from disparate data sources to obtain comprehensive diagnostic and prognostic knowledge regarding the health of the engine. Data fusion is the integration of data or information from multiple sources for the achievement of improved accuracy and more specific inferences than can be obtained from the use of a single sensor alone. The basic tenet underlying the data/ information fusion concept is to leverage all available information to enhance diagnostic visibility, increase diagnostic reliability and reduce the number of diagnostic false alarms. This report describes a basic PHM data fusion architecture being developed in alignment with the NASA C-17 PHM Flight Test program. The challenge of how to maximize the meaningful information extracted from disparate data sources to obtain enhanced diagnostic and prognostic information regarding the health and condition of the engine is the primary goal of this endeavor. To address this challenge, NASA Glenn Research Center, NASA Dryden Flight Research Center, and Pratt & Whitney have formed a team with several small innovative technology companies to plan and conduct a research project in the area of data fusion, as it applies to PHM. Methodologies being developed and evaluated have been drawn from a wide range of areas including artificial intelligence, pattern recognition, statistical estimation, and fuzzy logic. This report will provide a chronology and summary of the work accomplished under this research contract.

  10. High-frequency combustion instability control through acoustic modulation at the inlet boundary for liquid rocket engine applications

    NASA Astrophysics Data System (ADS)

    Bennewitz, John William

    model-predicted mode stability transition was consistent with experimental observations, supporting the premise that inlet acoustic modulation is a means to control high-frequency combustion instabilities. From the modal analysis, it may be deduced that the inlet impedance provides a damping mechanism for instability suppression. Combined, this work demonstrates the strategic application of acoustic modulation within an injector as a potential method to control high-frequency combustion instabilities for liquid rocket engine applications.

  11. Meeting Review: Airborne Aerosol Inlet Workshop

    NASA Technical Reports Server (NTRS)

    Baumgardner, Darrel; Huebert, Barry; Wilson, Chuck

    1991-01-01

    Proceedings from the Airborne Aerosol Inlet Workshop are presented. The two central topics of discussion were the role of aerosols in atmospheric processes and the difficulties in characterizing aerosols. The following topics were discussed during the working sessions: airborne observations to date; identification of inlet design issues; inlet modeling needs and directions; objectives for aircraft experiments; and future laboratory and wind tunnel studies.

  12. Development potential of Intermittent Combustion (I.C.) aircraft engines for commuter transport applications

    NASA Technical Reports Server (NTRS)

    Willis, E. A.

    1982-01-01

    An update on general aviation (g/a) and commuter aircraft propulsion research effort is reviewed. The following topics are discussed: on several advanced intermittent combustion engines emphasizing lightweight diesels and rotary stratified charge engines. The current state-of-the-art is evaluated for lightweight, aircraft suitable versions of each engine. This information is used to project the engine characteristics that can be expected on near-term and long-term time horizons. The key enabling technology requirements are identified for each engine on the long-term time horizon.

  13. Price-Weight Relationships of General Aviation, Helicopters, Transport Aircraft and Engines

    NASA Technical Reports Server (NTRS)

    Anderson, Joseph L.

    1981-01-01

    The NASA must assess its aeronautical research program with economic as well as performance measures. It thus is interested in what price a new technology aircraft would carry to make it attractive to the buyer. But what price a given airplane or helicopter will carry is largely a reflection of the manufacturer's assessment of the competitive market into which the new aircraft will be introduced. The manufacturer must weigh any new aerodynamic or system technology innovation he would add to an aircraft by the impact of this innovation upon the aircraft's cost to manufacture, economic attractiveness and price. The intent of this paper is to give price standards against which new technologies and the NASA's research program can be assessed. Using reported prices for sailplanes, general aviation, agriculture, helicopter, business and transport aircraft, price estimating relations in terms of engine and airframe characteristics have been developed. The relations are given in terms of the aircraft type, its manufactured empty weight, engine weight, horsepower or thrust. Factors for the effects of inflation are included to aid in making predictions of future aircraft prices. There are discussions of aircraft price in terms of number of passenger seats, airplane size and research and development costs related to an aircraft model, and indirectly how new technologies, aircraft complexity and inflation have affected these.

  14. Forward velocity effects on fan noise and the influence of inlet aeroacoustic design as measured in the NASA Ames 40 x 80 foot wind tunnel

    NASA Technical Reports Server (NTRS)

    Holm, R. G.; Langenbrunner, L. E.; Mccann, E. O.

    1981-01-01

    The inlet radiated noise of a turbofan engine was studied. The principal research objectives were to characterize or suppress such noise with particular regard to its tonal characteristics. The major portion of this research was conducted by using ground-based static testing without simulation of aircraft forward speed or aircraft installation-related aeroacoustic effects.

  15. Frequently-Asked Questions (FAQs) About Coastal Inlets and U.S. Army Corps of Engineers’ Coastal Inlets Research Program (CIRP)

    DTIC Science & Technology

    2006-02-01

    after deepening of a channel, if the side slopes exceed the stabile angle of repose of the sediment, or if loadings increase due to storm waves or...bypassing is the movement of sediment from the updrift to the downdrift side of an inlet by artificial means. Material may be taken from the...updrift fillet, a deposition basin, the dredged channel, the ebb shoal or flood shoal, or other nearshore shoals. The mechanism for bypassing the material

  16. Frequency-Asked Questions (FAQs) About Coastal Inlets and U.S. Army Corps of Engineers’ Coastal Inlets Research Program (CIRP)

    DTIC Science & Technology

    2006-02-01

    the stabile angle of repose of the sediment, or if loadings increase due to storm waves or earthquakes. e. Bed forms. Although not necessarily...updrift to the downdrift side of an inlet by artificial means. Material may be taken from the updrift fillet, a deposition basin, the dredged channel, the...ebb shoal or flood shoal, or other nearshore shoals. The mechanism for bypassing the material can be a hopper dredge, split hull dredge, pipeline

  17. Pollution reduction technology program for small jet aircraft engines: Class T1

    NASA Technical Reports Server (NTRS)

    Bruce, T. W.; Davis, F. G.; Mongia, H. C.

    1977-01-01

    Small jet aircraft engines (EPA class T1, turbojet and turbofan engines of less than 35.6 kN thrust) were evaluated with the objective of attaining emissions reduction consistent with performance constraints. Configurations employing the technological advances were screened and developed through full scale rig testing. The most promising approaches in full-scale engine testing were evaluated.

  18. The Role of Modern Control Theory in the Design of Controls for Aircraft Turbine Engines

    NASA Technical Reports Server (NTRS)

    Zeller, J.; Lehtinen, B.; Merrill, W.

    1982-01-01

    Accomplishments in applying Modern Control Theory to the design of controls for advanced aircraft turbine engines were reviewed. The results of successful research programs are discussed. Ongoing programs as well as planned or recommended future thrusts are also discussed.

  19. Effect of entry-lip design on aerodynamics and acoustics of high throat Mach number inlets for the quiet, clean, short-haul experimental engine

    NASA Technical Reports Server (NTRS)

    Miller, B. A.; Dastoli, B. J.; Wesoky, H. L.

    1975-01-01

    Results of scale model tests of high-throat-Mach-number inlets designed to suppress inlet-emitted engine machinery noise produced in a V/STOL wind tunnel are presented. A vacuum system was used to induce inlet airflow with a siren as a noise source. Inlet mass flow was 11.68 kilograms (25.75 lb. min) per second at a throat Mach number of 0.79. The effect of entry-lip design (contraction ratio and diameter ratio) on inlet total-pressure recovery, steady-state pressure distortion, performance at high incidence angles, and noise suppression was determined. With proper entry-lip design, total-pressure recovery in excess of 0.988 could be obtained statically at an average throat Mach number of 0.79. Total-pressure distortion was 5 percent. The reduction in the siren tone sound pressure level transmitted through the inlet was 10 to 14 db relative to that measured at throat Mach 0.6.

  20. Study of aerodynamic technology for single-cruise-engine VSTOL fighter/attack aircraft, phase 1

    NASA Technical Reports Server (NTRS)

    Foley, W. H.; Sheridan, A. E.; Smith, C. W.

    1982-01-01

    A conceptual design and analysis on a single engine VSTOL fighter/attack aircraft is completed. The aircraft combines a NASA/deHavilland ejector with vectored thrust and is capable of accomplishing the mission and point performance of type Specification 169, and a flight demonstrator could be built with an existing F101/DFE engine. The aerodynamic, aero/propulsive, and propulsive uncertainties are identified, and a wind tunnel program is proposed to address those uncertainties associated with wing borne flight.

  1. Results and status of the NASA aircraft engine emission reduction technology programs

    NASA Technical Reports Server (NTRS)

    Jones, R. E.; Diehl, L. A.; Petrash, D. A.; Grobman, J.

    1978-01-01

    The results of an aircraft engine emission reduction study are reviewed in detail. The capability of combustor concepts to produce significantly lower levels of exhaust emissions than present production combustors was evaluated. The development status of each combustor concept is discussed relative to its potential for implementation in aircraft engines. Also, the ability of these combustor concepts to achieve proposed NME and NCE EPA standards is discussed.

  2. Development of EPA aircraft piston engine emission standards. [for air quality

    NASA Technical Reports Server (NTRS)

    Houtman, W.

    1976-01-01

    Piston engine light aircraft are significant sources of carbon monoxide in the vicinity of high activity general aviation airports. Substantial reductions in carbon monoxide were achieved by fuel mixture leaning using improved fuel management systems. The air quality impact of the hydrocarbon and oxides of nitrogen emissions from piston engine light aircraft were insufficient to justify the design constraints being confronted in present control system developments.

  3. Fault mechanism analysis and simulation for continuity resistance test of electrical components in aircraft engine

    NASA Astrophysics Data System (ADS)

    Shi, Xudong; Yin, Yaping; Wang, Jialin; Sun, Zhaorong

    2017-01-01

    A large number of electrical components are used in civil aircraft engines, whose electrical circuits are usually intricate and complicated. Continuity resistance is an important parameter for the operating state of electrical components. Electrical continuity fault has serious impact on the reliability of the aircraft engine. In this paper, mathematical models of electrical components are established, and simulation is made by Simulink to analyze the electrical continuity fault.

  4. Jet aircraft engine exhaust emissions database development: Year 1990 and 2015 scenarios

    NASA Technical Reports Server (NTRS)

    Landau, Z. Harry; Metwally, Munir; Vanalstyne, Richard; Ward, Clay A.

    1994-01-01

    Studies relating to environmental emissions associated with the High Speed Civil Transport (HSCT) military jet and charter jet aircraft were conducted by McDonnell Douglas Aerospace Transport Aircraft. The report includes engine emission results for baseline 1990 charter and military scenario and the projected jet engine emissions results for a 2015 scenario for a Mach 1.6 HSCT charter and military fleet. Discussions of the methodology used in formulating these databases are provided.

  5. Physical characterization of the fine particle emissions from commercial aircraft engines during the Aircraft Particle Emissions Experiment (APEX) 1 to 3

    EPA Science Inventory

    The f1me particulate matter (PM) emissions from nine commercial aircraft engine models were determined by plume sampling during the three field campaigns of the Aircraft Particle Emissions Experiment (APEX). Ground-based measurements were made primarily at 30 m behind the engine ...

  6. A fast, uncoupled, compressible, two-dimensional, unsteady boundary layer algorithm with separation for engine inlets

    NASA Technical Reports Server (NTRS)

    Roach, Robert L.; Nelson, Chris; Sakowski, Barbara; Darling, Douglas; Vandewall, Allan G.

    1992-01-01

    A finite difference boundary layer algorithm was developed to model viscous effects when an inviscid core flow solution is given. This algorithm solved each boundary layer equation separately, then iterated to find a solution. Solving the boundary layer equations sequentially was 2.4 to 4.0 times faster than solving the boundary layer equations simultaneously. This algorithm used a modified Baldwin-Lomax turbulence model, a weighted average of forward and backward differencing of the pressure gradient, and a backward sweep of the pressure. With these modifications, the boundary layer algorithm was able to model flows with and without separation. The number of grid points used in the boundary layer algorithm affected the stability of the algorithm as well as the accuracy of the predictions of friction coefficients and momentum thicknesses. Results of this boundary layer algorithm compared well with experimental observations of friction coefficients and momentum thicknesses. In addition, when used interactively with an inviscid flow algorithm, this boundary layer algorithm corrected for viscous effects to give a good match with experimental observations for pressures in a supersonic inlet.

  7. S-Duct Engine Inlet Flow Control Using SDBD Plasma Streamwise Vortex Generators

    NASA Astrophysics Data System (ADS)

    Kelley, Christopher; He, Chuan; Corke, Thomas

    2009-11-01

    The results of a numerical simulation and experiment characterizing the performance of plasma streamwise vortex generators in controlling separation and secondary flow within a serpentine, diffusing duct are presented. A no flow control case is first run to check agreement of location of separation, development of secondary flow, and total pressure recovery between the experiment and numerical results. Upon validation, passive vane-type vortex generators and plasma streamwise vortex generators are implemented to increase total pressure recovery and reduce flow distortion at the aerodynamic interface plane: the exit of the S-duct. Total pressure recovery is found experimentally with a pitot probe rake assembly at the aerodynamic interface plane. Stagnation pressure distortion descriptors are also presented to show the performance increase with plasma streamwise vortex generators in comparison to the baseline no flow control case. These performance parameters show that streamwise plasma vortex generators are an effective alternative to vane-type vortex generators in total pressure recovery and total pressure distortion reduction in S-duct inlets.

  8. Extrapolating Ground-Based Aircraft Engine Exhaust Emissions to Cruise Conditions: Lessons From the 2013 ACCESS Chase Plane Experiment

    NASA Astrophysics Data System (ADS)

    Moore, R.; Shook, M.; Thornhill, K. L.; Winstead, E.; Anderson, B. E.

    2011-12-01

    Aircraft engine emissions constitute a tiny fraction of the global black carbon mass, but can have a disproportionate climatic impact because they are emitted high in the troposphere and in remote regions with otherwise low aerosol concentrations. Consequently, these particles are likely to strongly influence cirrus and contrail formation by acting as ice nuclei (IN). However, the ice nucleating properties of aircraft exhaust at relevant atmospheric conditions are not well known, and thus, the overall impact of aviation on cloud formation remains very uncertain. While a number of aircraft engine emissions studies have previously been conducted at sea level temperature and pressure (e.g., APEX, AAFEX-1 and 2), it unclear the extent to which exhaust emissions on the ground translate to emissions at cruise conditions with much lower inlet gas temperatures and pressures. To address this need, the NASA Alternative Fuel Effects on Contrails and Cruise Emissions (ACCESS) was conducted in February-April, 2013 to examine the aerosol and gas emissions from the NASA DC-8 under a variety of different fuel types, engine power, and altitude/meteorological conditions. Two different fuel types were studied: a traditional JP-8 fuel and a 50:50 blend of JP-8 and a camelina-based hydro-treated renewable jet (HRJ) fuel. Emissions were sampled using a comprehensive suite of gas- and aerosol-phase instrumentation integrated on an HU-25 Falcon jet that was positioned in the DC-8 exhaust plume at approximately 100-500m distance behind the engines. In addition, a four-hour ground test was carried out with sample probes positioned at 30 m behind each of the inboard engines. Measurements of aerosol concentration, size distribution, soot mass, and hygroscopicity were carried out along with trace gas measurements of CO2, NO, NO2, O3, and water vapor. NOx emissions were reconciled by employing the well-established Boeing method for normalizing engine fuel flow rates to STP; however, comparison

  9. Extrapolating Ground-Based Aircraft Engine Exhaust Emissions to Cruise Conditions: Lessons From the 2013 ACCESS Chase Plane Experiment

    NASA Astrophysics Data System (ADS)

    Moore, R.; Shook, M.; Thornhill, K. L.; Winstead, E.; Anderson, B. E.

    2013-12-01

    Aircraft engine emissions constitute a tiny fraction of the global black carbon mass, but can have a disproportionate climatic impact because they are emitted high in the troposphere and in remote regions with otherwise low aerosol concentrations. Consequently, these particles are likely to strongly influence cirrus and contrail formation by acting as ice nuclei (IN). However, the ice nucleating properties of aircraft exhaust at relevant atmospheric conditions are not well known, and thus, the overall impact of aviation on cloud formation remains very uncertain. While a number of aircraft engine emissions studies have previously been conducted at sea level temperature and pressure (e.g., APEX, AAFEX-1 and 2), it unclear the extent to which exhaust emissions on the ground translate to emissions at cruise conditions with much lower inlet gas temperatures and pressures. To address this need, the NASA Alternative Fuel Effects on Contrails and Cruise Emissions (ACCESS) was conducted in February-April, 2013 to examine the aerosol and gas emissions from the NASA DC-8 under a variety of different fuel types, engine power, and altitude/meteorological conditions. Two different fuel types were studied: a traditional JP-8 fuel and a 50:50 blend of JP-8 and a camelina-based hydro-treated renewable jet (HRJ) fuel. Emissions were sampled using a comprehensive suite of gas- and aerosol-phase instrumentation integrated on an HU-25 Falcon jet that was positioned in the DC-8 exhaust plume at approximately 100-500m distance behind the engines. In addition, a four-hour ground test was carried out with sample probes positioned at 30 m behind each of the inboard engines. Measurements of aerosol concentration, size distribution, soot mass, and hygroscopicity were carried out along with trace gas measurements of CO2, NO, NO2, O3, and water vapor. NOx emissions were reconciled by employing the well-established Boeing method for normalizing engine fuel flow rates to STP; however, comparison

  10. Space Shuttle Main Engine structural analysis and data reduction/evaluation. Volume 4: High pressure fuel turbo-pump inlet housing analysis

    NASA Technical Reports Server (NTRS)

    Pool, Kirby V.

    1989-01-01

    The analysis performed on the Space Shuttle Main Engine (SSME) High Pressure Fuel Turbopump (HPFTP) inlet housings is summarized. Three DIAL finite element models were build to aid in assessing the structural life of the welds and fillets at the vanes. Complete results are given.

  11. A throat-bypass stability-bleed system using relief valves to increase the transient stability of a mixed-compression inlet. [YF-12 aircraft inlet tests in the Lewis 10 by 10 ft supersonic wind tunnel

    NASA Technical Reports Server (NTRS)

    Neiner, G. H.; Dustin, M. O.; Cole, G. L.

    1979-01-01

    A stability-bleed system was installed in a YF-12 flight inlet that was subjected to internal and external airflow disturbances in the NASA Lewis 10 by 10 foot supersonic wind tunnel. The purpose of the system is to allow higher inlet performance while maintaining a substantial tolerance (without unstart) to internal and external disturbances. At Mach numbers of 2.47 and 2.76, the inlet tolerance to decreases in diffuser-exit corrected airflow was increased by approximately 10 percent of the operating-point airflow. The stability-bleed system complemented the terminal-shock-control system of the inlet and did not show interaction problems. For disturbances which caused a combined decrease in Mach number and increase in angle of attack, the system with valves operative kept the inlet started 4 to 28 times longer than with the valves inoperative. Hence, the stability system provides additional time for the inlet control system to react and prevent unstart. This was observed for initial Mach numbers of 2.55 and 2.68. For slow increase in angle of attack at Mach 2.47 and 2.76, the system kept the inlet started beyond the steady-state unstart angle. However, the maximum transient angles of attack without unstart could not be determined because wind-tunnel mechanical-stop limits for angle of attack were reached.

  12. An inventory of particle and gaseous emissions from large aircraft thrust engine operations at an airport

    NASA Astrophysics Data System (ADS)

    Mazaheri, M.; Johnson, G. R.; Morawska, L.

    2011-07-01

    Published particle number emission factors for aircraft operations remain very sparse and so far such emissions have not been included in the International Civil Aviation Organization (ICAO) databases. This work addresses this gap in knowledge by utilizing recent progress in the quantification of aircraft particle emissions. Annual emissions of particle number (PN), particle mass (PM 2.5) and NO x throughout the aircraft landing and takeoff (LTO) cycles and ground running procedures (GRP) are presented for aircraft using Brisbane Airport BNE (domestic and international). The aircraft are grouped according to an airframe based classification system. The resulting data are then used to develop an emissions inventory for large aircraft thrust engine operations on the ground, during LTO cycles and GRP, at the Airport. Annual PN, PM 2.5 and NO x emissions from large aircraft operations during LTO cycles and GRP at BNE were 1.98 × 10 24 yr -1, 1.35 × 10 4 kg yr -1 and 8.13 × 10 5 kg yr -1, respectively. Results showed that LTO cycles contribute more than 97% of these annual emissions at BNE in comparison to GRP related emissions. Analysis of the LTO cycle contribution to the daily emissions showed that the contribution of the climbout mode is considerably higher than for other individual LTO operational modes. Emissions during aircraft departures were significantly higher than those during arrival operations, due to the higher aircraft engine emission rates during takeoff and climbout.

  13. Adaptive Failure Compensation for Aircraft Tracking Control Using Engine Differential Based Model

    NASA Technical Reports Server (NTRS)

    Liu, Yu; Tang, Xidong; Tao, Gang; Joshi, Suresh M.

    2006-01-01

    An aircraft model that incorporates independently adjustable engine throttles and ailerons is employed to develop an adaptive control scheme in the presence of actuator failures. This model captures the key features of aircraft flight dynamics when in the engine differential mode. Based on this model an adaptive feedback control scheme for asymptotic state tracking is developed and applied to a transport aircraft model in the presence of two types of failures during operation, rudder failure and aileron failure. Simulation results are presented to demonstrate the adaptive failure compensation scheme.

  14. 14 CFR 43.7 - Persons authorized to approve aircraft, airframes, aircraft engines, propellers, appliances, or...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... data approved by the Administrator. (e) The holder of an air carrier operating certificate or an... holder of a repairman certificate (light-sport aircraft) with a maintenance rating may approve an aircraft issued a special airworthiness certificate in light-sport category for return to service,...

  15. Maritime Patrol Aircraft Engine Study P&WA Derivative Engines. Volume II. Performance Data.

    DTIC Science & Technology

    1979-04-30

    U) APR 79 R C NEWELL. P W HERRICK N62269-78C-0GIG UNCLASSIFIED PWA -FR-10966B/C"VOL-2 NAC-79132-60-VOL-2 NL mmEhE mhm 111 1 4;.c~ 111128 12.5 IIIIIII...MARITIME PATROL AIRCRAFT ENGINE STUDT PIWA DERIVATIVE ENGINES. --EC(U) APR 79 R C NEWELL. P W HERRICK N62269-78-C-010 UNCLASSIFIED PWA -FR-10966B/C-VOL-2 NADC...0.80 823. n. 524 -165. 51.3 5.8 1635. MAX .LIft 5.000. 0.85 6289 o 0.333 249. 125.3 17.*6 2535. MAX CKUISE 45000. 0.85 5629. 0.331 150.. 11,.6 16.3

  16. Engine-induced structural-borne noise in a general aviation aircraft

    NASA Technical Reports Server (NTRS)

    Unruh, J. F.; Scheidt, D. C.; Pomerening, D. J.

    1979-01-01

    Structural borne interior noise in a single engine general aviation aircraft was studied to determine the importance of engine induced structural borne noise and to determine the necessary modeling requirements for the prediction of structural borne interior noise. Engine attached/detached ground test data show that engine induced structural borne noise is a primary interior noise source for the single engine test aircraft, cabin noise is highly influenced by responses at the propeller tone, and cabin acoustic resonances can influence overall noise levels. Results from structural and acoustic finite element coupled models of the test aircraft show that wall flexibility has a strong influence on fundamental cabin acoustic resonances, the lightweight fuselage structure has a high modal density, and finite element analysis procedures are appropriate for the prediction of structural borne noise.

  17. Effect of broadened-specification fuels on aircraft engines and fuel systems

    NASA Technical Reports Server (NTRS)

    Rudey, R. A.

    1979-01-01

    A wide variety of studies on the potential effects of broadened-specification fuels on future aircraft engines and fuel systems are summarized. The compositions and characteristics of aircraft fuels that may be derived from current and future crude-oil sources are described, and the most critical properties that may effect aircraft engines and fuel systems are identified and discussed. The problems that are most likely to be encountered because of changes in selected fuel properties are explored; and the related effects on engine performance, component durability and maintenance, and aircraft fuel-system performance are examined. The ability of current technology to accept possible future fuel specification changes is assessed and selected technological advances that can reduce the severity of the potential problems are illustrated.

  18. Factors to Consider in Designing Aerosol Inlet Systems for Engine Exhaust Plume Sampling

    NASA Technical Reports Server (NTRS)

    Anderson, Bruce

    2004-01-01

    This document consists of viewgraphs of charts and diagrams of considerations to take when sampling the engine exhaust plume. It includes a chart that compares the emissions from various fuels, a diagram and charts of the various processes and conditions that influence the particulate size and concentration,

  19. Determination and Applications of Environmental Costs at Different Sized Airports: Aircraft Noise and Engine Emissions

    NASA Technical Reports Server (NTRS)

    Lu, Cherie; Lierens, Abigail

    2003-01-01

    With the increasing trend of charging for externalities and the aim of encouraging the sustainable development of the air transport industry, there is a need to evaluate the social costs of these undesirable side effects, mainly aircraft noise and engine emissions, for different airports. The aircraft noise and engine emissions social costs are calculated in monetary terms for five different airports, ranging from hub airports to small regional airports. The number of residences within different levels of airport noise contours and the aircraft noise classifications are the main determinants for accessing aircraft noise social costs. Whist, based on the damages of different engine pollutants on the human health, vegetation, materials, aquatic ecosystem and climate, the aircraft engine emissions social costs vary from engine types to aircraft categories. The results indicate that the relationship appears to be curvilinear between environmental costs and the traffic volume of an airport. The results and methodology of environmental cost calculation could input for to the proposed European wide harmonized noise charges as well as the social cost benefit analysis of airports.

  20. Lightweight two-stroke cycle aircraft diesel engine technology enablement program, volume 3

    NASA Technical Reports Server (NTRS)

    Freen, P. D.; Berenyi, S. G.; Brouwers, A. P.; Moynihan, M. E.

    1985-01-01

    An experimental Single Cylinder Test Engine Program is conducted to confirm the analytically projected performance of a two-stroke cycle diesel engine for aircraft applications. Testing confirms the ability of a proposed 4-cylinder version of such an engine to reach the target power at altitude in a highly turbocharged configuration. The experimental program defines all necessary parameters to permit design of a multicylinder engine for eventual flight applications.

  1. Advanced liquid-cooled, turbocharged and intercooled stratified charge rotary engines for aircraft

    NASA Technical Reports Server (NTRS)

    Mount, Robert E.; Bartel, John; Hady, William F.

    1987-01-01

    Developments concerning stratified-charge rotary (SCR) engines over the past 10 years are reviewed. Aircraft engines being developed using SCR technology are shown and described, and the ability of such technology to meet general aviation engine needs is considered. Production timing and availability of SCR technology for the development of aviation rotary engines are discussed, and continuing efforts toward improving this technology, including NASA efforts, are described.

  2. Lightweight two-stroke cycle aircraft diesel engine technology enablement program, volume 2

    NASA Technical Reports Server (NTRS)

    Freen, P. D.; Berenyi, S. G.; Brouwers, A. P.; Moynihan, M. E.

    1985-01-01

    An experimental Single Cylinder Test Engine Program is conducted to confirm the analytically projected performance of a two-stroke cycle diesel engine for aircraft applications. Testing confirms the ability of a proposed 4-cylinder version of such an engine to reach the target power at altitude in a highly turbocharged configuration. The experimental program defines all necessary parameters to permit a design of a multicylinder engine for eventual flight applications.

  3. Thermodynamic efficiency of present types of internal combustion engines for aircraft

    NASA Technical Reports Server (NTRS)

    Lucke, Charles E

    1917-01-01

    Report presents requirements of internal combustion engines suitable for aircraft. Topics include: (1) service requirements for aeronautic engines - power versus weight, reliability, and adaptability factors, (2) general characteristics of present aero engines, (3) aero engine processes and functions of parts versus power-weight ratio, reliability, and adaptability factors, and (4) general arrangement, form, proportions, and materials of aero parts - power-weight ratio, reliability, and adaptability.

  4. Results of T56 Engine Performance Monitoring Trial in Hercules Aircraft, February-July 1977.

    DTIC Science & Technology

    1981-04-01

    Engine Removals/Rejections 2 3.1.1 Resume 5 3.2 Faults not Associated with Engine Removals 5 * NOTATION REFERENCES I TABLES FIGURES APPENDIX 1 ANNEX A...in those cases in which performance monitoring could have been expected to reflect the fault , the appropriate engine performance trend plots were...the appropriate EL 500. (ihis form is used by aircrew and maiintenazice personnel to record any aircraft/ engine fault and its subsequent

  5. IPAC-Inlet Performance Analysis Code

    NASA Technical Reports Server (NTRS)

    Barnhart, Paul J.

    1997-01-01

    A series of analyses have been developed which permit the calculation of the performance of common inlet designs. The methods presented are useful for determining the inlet weight flows, total pressure recovery, and aerodynamic drag coefficients for given inlet geometric designs. Limited geometric input data is required to use this inlet performance prediction methodology. The analyses presented here may also be used to perform inlet preliminary design studies. The calculated inlet performance parameters may be used in subsequent engine cycle analyses or installed engine performance calculations for existing uninstalled engine data.

  6. Method for Determining Optimum Injector Inlet Geometry

    NASA Technical Reports Server (NTRS)

    Trinh, Huu P. (Inventor); Myers, W. Neill (Inventor)

    2015-01-01

    A method for determining the optimum inlet geometry of a liquid rocket engine swirl injector includes obtaining a throttleable level phase value, volume flow rate, chamber pressure, liquid propellant density, inlet injector pressure, desired target spray angle and desired target optimum delta pressure value between an inlet and a chamber for a plurality of engine stages. The method calculates the tangential inlet area for each throttleable stage. The method also uses correlation between the tangential inlet areas and delta pressure values to calculate the spring displacement and variable inlet geometry of a liquid rocket engine swirl injector.

  7. MPT Prediction of Aircraft-Engine Fan Noise

    NASA Technical Reports Server (NTRS)

    Connell, Stuart D.

    2004-01-01

    A collection of computer programs has been developed that implements a procedure for predicting multiple-pure-tone (MPT) noise generated by fan blades of an aircraft engine (e.g., a turbofan engine). MPT noise arises when the fan is operating with supersonic relative tip Mach No. Under this flow condition, there is a strong upstream running shock. The strength and position of this shock are very sensitive to blade geometry variations. For a fan where all the blades are identical, the primary tone observed upstream of the fan will be the blade passing frequency. If there are small variations in geometry between blades, then tones below the blade passing frequency arise MPTs. Stagger angle differences as small as 0.1 can give rise to significant MPT. It is also noted that MPT noise is more pronounced when the fan is operating in an unstarted mode. Computational results using a three-dimensional flow solver to compute the complete annulus flow with non-uniform fans indicate that MPT noise can be estimated in a relatively simple way. Hence, once the effect of a typical geometry variation of one blade in an otherwise uniform blade row is known, the effect of all the blades being different can be quickly computed via superposition. Two computer programs that were developed as part of this work are used in conjunction with a user s computational fluid dynamics (CFD) code to predict MPT spectra for a fan with a specified set of geometric variations: (1) The first program ROTBLD reads the users CFD solution files for a single blade passage via an API (Application Program Interface). There are options to replicate and perturb the geometry with typical variations stagger, camber, thickness, and pitch. The multi-passage CFD solution files are then written in the user s file format using the API. (2) The second program SUPERPOSE requires two input files: the first is the circumferential upstream pressure distribution extracted from the CFD solution on the multi-passage mesh

  8. Study of LH2-fueled topping cycle engine for aircraft propulsion

    NASA Technical Reports Server (NTRS)

    Turney, G. E.; Fishbach, L. H.

    1983-01-01

    An analytical investigation was made of a topping cycle aircraft engine system which uses a cryogenic fuel. This system consists of a main turboshaft engine which is mechanically coupled (by cross-shafting) to a topping loop which augments the shaft power output of the system. The thermodynamic performance of the topping cycle engine was analyzed and compared with that of a reference (conventional-type) turboshaft engine. For the cycle operating conditions selected, the performance of the topping cycle engine in terms of brake specific fuel consumption (bsfc) was determined to be about 12 percent better than that of the reference turboshaft engine. Engine weights were estimated for both the topping cycle engine and the reference turboshaft engine. These estimates were based on a common shaft power output for each engine. Results indicate that the weight of the topping cycle engine is comparable to that of the reference turboshaft engine.

  9. Inlet Flow Characteristics During Rapid Maneuvers for an F/A-18A Airplane

    NASA Technical Reports Server (NTRS)

    Steenken, William G.; Williams, John G.; Walsh, Kevin R.

    1999-01-01

    The F404-GE-400 engine powered F/A-18A High Alpha Research Vehicle (HARV) was used to examine the characteristics of inlet airflow during rapid aircraft maneuvers. A study of the degree of similarity between inlet data obtained during rapid aircraft maneuvers and inlet data obtained at steady aerodynamic attitudes was conducted at the maximum engine airflow of approximately 145 Ibm/sec using a computer model that was generated from inlet data obtained during steady aerodynamic maneuvers. Results show that rapid-maneuver inlet recoveries agreed very well with the recoveries obtained at equivalent stabilized angle-of-attack conditions. The peak dynamic circumferential distortion values obtained during rapid maneuvers agreed within 0.01 units of distortion over the 10 - 38 degree angle of attack range with the values obtained during steady aerodynamic maneuvers while similar agreement was found for the peak dynamic radial distortion values up to 29 degrees angle-of-attack. Exceedences of the rapid-maneuver peak dynamic circumferential distortion values relative to the peak distortion model values at steady attitudes occurred only at low or negative angles of attack and were inconsequential from an engine-stability assessment point of view. The results of this study validate the current industry practice of testing at steady aerodynamic conditions to characterize inlet recovery and peak dynamic distortion levels.

  10. 14 CFR 43.7 - Persons authorized to approve aircraft, airframes, aircraft engines, propellers, appliances, or...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... maintenance, preventive maintenance, rebuilding, or alteration. 43.7 Section 43.7 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT MAINTENANCE, PREVENTIVE MAINTENANCE..., propellers, appliances, or component parts for return to service after maintenance, preventive...

  11. 14 CFR 43.7 - Persons authorized to approve aircraft, airframes, aircraft engines, propellers, appliances, or...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... maintenance, preventive maintenance, rebuilding, or alteration. 43.7 Section 43.7 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT MAINTENANCE, PREVENTIVE MAINTENANCE..., propellers, appliances, or component parts for return to service after maintenance, preventive...

  12. 14 CFR 43.7 - Persons authorized to approve aircraft, airframes, aircraft engines, propellers, appliances, or...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... maintenance, preventive maintenance, rebuilding, or alteration. 43.7 Section 43.7 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT MAINTENANCE, PREVENTIVE MAINTENANCE..., propellers, appliances, or component parts for return to service after maintenance, preventive...

  13. 14 CFR 43.7 - Persons authorized to approve aircraft, airframes, aircraft engines, propellers, appliances, or...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... maintenance, preventive maintenance, rebuilding, or alteration. 43.7 Section 43.7 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT MAINTENANCE, PREVENTIVE MAINTENANCE..., propellers, appliances, or component parts for return to service after maintenance, preventive...

  14. A simulator investigation of engine failure compensation for powered-lift STOL aircraft

    NASA Technical Reports Server (NTRS)

    Nieuwenhuijse, A. W.; Franklin, J. A.

    1974-01-01

    A piloted simulator investigation of various engine failure compensation concepts for powered-lift STOL aircraft was carried out at the Ames Research Center. The purpose of this investigation was to determine the influence of engine failure compensation on recovery from an engine failure during the landing approach and on the precision of the STOL landing. The various concepts include: (1) cockpit warning lights to cue the pilot of an engine failure, (2) programmed thrust and roll trim compensation, (3) thrust command and (4) flight-path stabilization. The aircraft simulated was a 150 passenger four-engine, externally blown flap civil STOL transport having a 90 psf wing loading and a .56 thrust to weight ratio. Results of the simulation indicate that the combination of thrust command and flight-path stabilization offered the best engine-out landing performance in turbulence and did so over the entire range of altitudes for which engine failures occurred.

  15. Minimum Specific Fuel Consumption of a Liquid-Cooled Multicylinder Aircraft Engine as Affected by Compression Ratio and Engine Operating Conditions

    NASA Technical Reports Server (NTRS)

    Brun, Rinaldo J.; Feder, Melvin S.; Harries, Myron L.

    1947-01-01

    An investigation was conducted on a 12-cylinder V-type liquid-cooled aircraft engine of 1710-cubic-inch displacement to determine the minimum specific fuel consumption at constant cruising engine speed and compression ratios of 6.65, 7.93, and 9.68. At each compression ratio, the effect.of the following variables was investigated at manifold pressures of 28, 34, 40, and 50 inches of mercury absolute: temperature of the inlet-air to the auxiliary-stage supercharger, fuel-air ratio, and spark advance. Standard sea-level atmospheric pressure was maintained at the auxiliary-stage supercharger inlet and the exhaust pressure was atmospheric. Advancing the spark timing from 34 deg and 28 deg B.T.C. (exhaust and intake, respectively) to 42 deg and 36 deg B.T.C. at a compression ratio of 6.65 resulted in a decrease of approximately 3 percent in brake specific fuel consumption. Further decreases in brake specific fuel consumption of 10.5 to 14.1 percent (depending on power level) were observed as the compression ratio was increased from 6.65 to 9.68, maintaining at each compression ratio the spark advance required for maximum torque at a fuel-air ratio of 0.06. This increase in compression ratio with a power output of 0.585 horsepower per cubic inch required a change from . a fuel- lend of 6-percent triptane with 94-percent 68--R fuel at a compression ratio of 6.65 to a fuel blend of 58-percent, triptane with 42-percent 28-R fuel at a compression ratio of 9.68 to provide for knock-free engine operation. As an aid in the evaluation of engine mechanical endurance, peak cylinder pressures were measured on a single-cylinder engine at several operating conditions. Peak cylinder pressures of 1900 pounds per square inch can be expected at a compression ratio of 9.68 and an indicated mean effective pressure of 320 pounds per square inch. The engine durability was considerably reduced at these conditions.

  16. Role of inlet reactant mixedness on the thermodynamic performance of a rotating detonation engine

    NASA Astrophysics Data System (ADS)

    Nordeen, C. A.; Schwer, D.; Schauer, F.; Hoke, J.; Barber, T.; Cetegen, B. M.

    2016-07-01

    Rotating detonation engines have the potential to achieve the high propulsive efficiencies of detonation cycles in a simple and effective annular geometry. A two-dimensional Euler simulation is modified to include mixing factors to simulate the imperfect mixing of injected reactant streams. Contrary to expectations, mixing is shown to have a minimal impact on performance. Oblique detonation waves are shown to increase local stream thermal efficiency, which compensates for other losses in the flow stream. The degree of reactant mixing is, however, a factor in controlling the stability and existence of rotating detonations.

  17. Evaluation of Methods for the Determination of Black Carbon Emissions from an Aircraft Gas Turbine Engine

    EPA Science Inventory

    The emissions from aircraft gas turbine engines consist of nanometer size black carbon (BC) particles plus gas-phase sulfur and organic compounds which undergo gas-to-particle conversion downstream of the engine as the plume cools and dilutes. In this study, four BC measurement ...

  18. Minimum time acceleration of aircraft turbofan engines by using an algorithm based on nonlinear programming

    NASA Technical Reports Server (NTRS)

    Teren, F.

    1977-01-01

    Minimum time accelerations of aircraft turbofan engines are presented. The calculation of these accelerations was made by using a piecewise linear engine model, and an algorithm based on nonlinear programming. Use of this model and algorithm allows such trajectories to be readily calculated on a digital computer with a minimal expenditure of computer time.

  19. The Effect of Modified Control Limits on the Performance of a Generic Commercial Aircraft Engine

    NASA Technical Reports Server (NTRS)

    Csank, Jeffrey T.; May, Ryan D.; Gou, Ten-Huei; Litt, Jonathan S.

    2012-01-01

    This paper studies the effect of modifying the control limits of an aircraft engine to obtain additional performance. In an emergency situation, the ability to operate an engine above its normal operating limits and thereby gain additional performance may aid in the recovery of a distressed aircraft. However, the modification of an engine s limits is complex due to the risk of an engine failure. This paper focuses on the tradeoff between enhanced performance and risk of either incurring a mechanical engine failure or compromising engine operability. The ultimate goal is to increase the engine performance, without a large increase in risk of an engine failure, in order to increase the probability of recovering the distressed aircraft. The control limit modifications proposed are to extend the rotor speeds, temperatures, and pressures to allow more thrust to be produced by the engine, or to increase the rotor accelerations and allow the engine to follow a fast transient. These modifications do result in increased performance; however this study indicates that these modifications also lead to an increased risk of engine failure.

  20. Commercial aircraft engine emissions characterization of in-use aircraft at Hartsfield-Jackson Atlanta International Airport.

    PubMed

    Herndon, Scott C; Jayne, John T; Lobo, Prem; Onasch, Timothy B; Fleming, Gregg; Hagen, Donald E; Whitefield, Philip D; Miake-Lye, Richard C

    2008-03-15

    The emissions from in-use commercial aircraft engines have been analyzed for selected gas-phase species and particulate characteristics using continuous extractive sampling 1-2 min downwind from operational taxi- and runways at Hartsfield-Jackson Atlanta International Airport. Using the aircraft tail numbers, 376 plumes were associated with specific engine models. In general, for takeoff plumes, the measured NOx emission index is lower (approximately 18%) than that predicted by engine certification data corrected for ambient conditions. These results are an in-service observation of the practice of "reduced thrust takeoff". The CO emission index observed in ground idle plumes was greater (up to 100%) than predicted by engine certification data for the 7% thrust condition. Significant differences are observed in the emissions of black carbon and particle number among different engine models/technologies. The presence of a mode at approximately 65 nm (mobility diameter) associated with takeoff plumes and a smaller mode at approximately 25 nm associated with idle plumes has been observed. An anticorrelation between particle mass loading and particle number concentration is observed.

  1. Preliminary Axial Flow Turbine Design and Off-Design Performance Analysis Methods for Rotary Wing Aircraft Engines. Part 2; Applications

    NASA Technical Reports Server (NTRS)

    Chen, Shu-cheng, S.

    2009-01-01

    In this paper, preliminary studies on two turbine engine applications relevant to the tilt-rotor rotary wing aircraft are performed. The first case-study is the application of variable pitch turbine for the turbine performance improvement when operating at a substantially lower shaft speed. The calculations are made on the 75 percent speed and the 50 percent speed of operations. Our results indicate that with the use of the variable pitch turbines, a nominal (3 percent (probable) to 5 percent (hypothetical)) efficiency improvement at the 75 percent speed, and a notable (6 percent (probable) to 12 percent (hypothetical)) efficiency improvement at the 50 percent speed, without sacrificing the turbine power productions, are achievable if the technical difficulty of turning the turbine vanes and blades can be circumvented. The second casestudy is the contingency turbine power generation for the tilt-rotor aircraft in the One Engine Inoperative (OEI) scenario. For this study, calculations are performed on two promising methods: throttle push and steam injection. By isolating the power turbine and limiting its air mass flow rate to be no more than the air flow intake of the take-off operation, while increasing the turbine inlet total temperature (simulating the throttle push) or increasing the air-steam mixture flow rate (simulating the steam injection condition), our results show that an amount of 30 to 45 percent extra power, to the nominal take-off power, can be generated by either of the two methods. The methods of approach, the results, and discussions of these studies are presented in this paper.

  2. Investigation of Thrust Augmentation of a 1600-pound Thrust Centrifugal-flow-type Turbojet Engine by Injection of Refrigerants at Compressor Inlets

    NASA Technical Reports Server (NTRS)

    Jones, William L.; Dowman, Harry W.

    1947-01-01

    Investigations were conducted to determine effectiveness of refrigerants in increasing thrust of turbojet engines. Mixtures of water an alcohol were injected for a range of total flows up to 2.2 lb/sec. Kerosene was injected into inlets covering a range of injected flows up to approximately 30% of normal engine fuel flow. Injection of 2.0 lb/sec of water alone produced an increase in thrust of 35.8% of rate engine conditions and kerosene produced a negligible increase in thrust. Carbon dioxide increased thrust 23.5 percent.

  3. A Feasibility Study of Life-Extending Controls for Aircraft Turbine Engines Using a Generic Air Force Model (Preprint)

    DTIC Science & Technology

    2006-12-01

    engine model is a detailed, physics-based engine model of a two-spool, non-augmented, low bypass ratio engine developed using MATLAB/ Simulink ® [9]. The...AFRL-PR-WP-TP-2007-218 A FEASIBILITY STUDY OF LIFE- EXTENDING CONTROLS FOR AIRCRAFT TURBINE ENGINES USING A GENERIC AIR FORCE MODEL (PREPRINT...SUBTITLE A FEASIBILITY STUDY OF LIFE-EXTENDING CONTROLS FOR AIRCRAFT TURBINE ENGINES USING A GENERIC AIR FORCE MODEL (PREPRINT) 5c. PROGRAM ELEMENT

  4. Blended Wing Body Systems Studies: Boundary Layer Ingestion Inlets With Active Flow Control

    NASA Technical Reports Server (NTRS)

    Geiselhart, Karl A. (Technical Monitor); Daggett, David L.; Kawai, Ron; Friedman, Doug

    2003-01-01

    A CFD analysis was performed on a Blended Wing Body (BWB) aircraft with advanced, turbofan engines analyzing various inlet configurations atop the aft end of the aircraft. The results are presented showing that the optimal design for best aircraft fuel efficiency would be a configuration with a partially buried engine, short offset diffuser using active flow control, and a D-shaped inlet duct that partially ingests the boundary layer air in flight. The CFD models showed that if active flow control technology can be satisfactorily developed, it might be able to control the inlet flow distortion to the engine fan face and reduce the powerplant performance losses to an acceptable level. The weight and surface area drag benefits of a partially submerged engine shows that it might offset the penalties of ingesting the low energy boundary layer air. The combined airplane performance of such a design might deliver approximately 5.5% better aircraft fuel efficiency over a conventionally designed, pod-mounted engine.

  5. Lightweight aircraft engines, the potential and problems for use of automotive fuels

    NASA Technical Reports Server (NTRS)

    Patterson, D. J.

    1983-01-01

    A comprehensive data research and analysis for evaluating the use of automotive fuels as a substitute for aviation grade fuel by piston-type general aviation aircraft engines is presented. Historically known problems and potential problems with fuels were reviewed for possible impact relative to application to an aircraft operational environment. This report reviews areas such as: fuel specification requirements, combustion knock, preignition, vapor lock, spark plug fouling, additives for fuel and oil, and storage stability.

  6. Design study: A 186 kW lightweight diesel aircraft engine

    NASA Technical Reports Server (NTRS)

    Brouwers, A. P.

    1980-01-01

    The design of an aircraft engine capable of developing 186 kW shaft power at a 7620 m altitude is described. The 186 kW design takes into account expected new developments in aircraft designs resulting in a reassessment of the power requirements at the cruise mode operation. Based on the results of this analysis a three phase technology development program is projected resulting in production dates of 1985, 1992, and 2000.

  7. A Study of Bird Ingestions Into Large High Bypass Ratio Turbine Aircraft Engines.

    DTIC Science & Technology

    1984-09-01

    4. SUMMARY 37 5. CONCLUSIONS 39 6. UEFERENCES 41 APPENDICES A - Comparison of HBPR Engine Aircraft B - HIVE Engines C - Statistical Procesures D...allow a reliable assessment of the bird ingestion phenomenon. Sufficient data to conduct a statistical analysis based upon the numbers, weights, and...species of birds. Sufficient data to conduct a statistical analysis of the engine damage resulting from a bird ingestion - considering the bird number

  8. 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.

  9. An Object-oriented Computer Code for Aircraft Engine Weight Estimation

    NASA Technical Reports Server (NTRS)

    Tong, Michael T.; Naylor, Bret A.

    2008-01-01

    Reliable engine-weight estimation at the conceptual design stage is critical to the development of new aircraft engines. It helps to identify the best engine concept amongst several candidates. At NASA Glenn (GRC), the Weight Analysis of Turbine Engines (WATE) computer code, originally developed by Boeing Aircraft, has been used to estimate the engine weight of various conceptual engine designs. The code, written in FORTRAN, was originally developed for NASA in 1979. Since then, substantial improvements have been made to the code to improve the weight calculations for most of the engine components. Most recently, to improve the maintainability and extensibility of WATE, the FORTRAN code has been converted into an object-oriented version. The conversion was done within the NASA s NPSS (Numerical Propulsion System Simulation) framework. This enables WATE to interact seamlessly with the thermodynamic cycle model which provides component flow data such as airflows, temperatures, and pressures, etc. that are required for sizing the components and weight calculations. The tighter integration between the NPSS and WATE would greatly enhance system-level analysis and optimization capabilities. It also would facilitate the enhancement of the WATE code for next-generation aircraft and space propulsion systems. In this paper, the architecture of the object-oriented WATE code (or WATE++) is described. Both the FORTRAN and object-oriented versions of the code are employed to compute the dimensions and weight of a 300- passenger aircraft engine (GE90 class). Both versions of the code produce essentially identical results as should be the case. Keywords: NASA, aircraft engine, weight, object-oriented

  10. Modeling and analysis of the TF30-P-3 compressor system with inlet pressure distortion

    NASA Technical Reports Server (NTRS)

    Mazzawy, R. S.; Banks, G. A.

    1976-01-01

    Circumferential inlet distortion testing of a TF30-P-3 afterburning turbofan engine was conducted at NASA-Lewis Research Center. Pratt and Whitney Aircraft analyzed the data using its multiple segment parallel compressor model and classical compressor theory. Distortion attenuation analysis resulted in a detailed flow field calculation with good agreement between multiple segment model predictions and the test data. Sensitivity of the engine stall line to circumferential inlet distortion was calculated on the basis of parallel compressor theory to be more severe than indicated by the data. However, the calculated stall site location was in agreement with high response instrumentation measurements.

  11. Engine/airframe compatibility studies for supersonic cruise aircraft

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Technology assessment studies were conducted to provide an updated technology base from which an advanced supersonic cruise aircraft can be produced with a high probability of success. An assessment of the gains available through the application of advanced technologies in aerodynamics, propulsion, acoustics, structures, materials, and active controls is developed. The potential market and range requirements as well as economic factors including payload, speed, airline operating costs, and airline profitability are analyzed. The conceptual design of the baseline aircraft to be used in assessing the technology requirements is described.

  12. The STOL performance of a two-engine, USB powered-lift aircraft with cross-shafted fans

    NASA Technical Reports Server (NTRS)

    Stevens, V. C.; Wilson, S. B., III; Zola, C. A.

    1985-01-01

    The short takeoff and landing capabilities that characterize the performance of powered-lift aircraft are dependent on engine thrust and are, therefore, severely affected by loss of an engine. This paper shows that the effects of engine loss on the short takeoff and landing performance of powered-lift aircraft can be effectively mitigated by cross-shafting the engine fans in a twin-engine configuration. Engine-out takeoff and landing performances are compared for three powered-lift aircraft configurations: one with four engines, one with two engines, and one with two engines in which the fans are cross-shafted. The results show that the engine-out takeoff and landing performance of the cross-shafted two-engine configuration is significantly better than that of the two-engine configuration without cross-shafting.

  13. A Sensitivity Study of Commercial Aircraft Engine Response for Emergency Situations

    NASA Technical Reports Server (NTRS)

    Csank, Jeffrey T.; May, Ryan D.; Litt, Jonathan S.; Guo, Ten-Huei

    2011-01-01

    This paper contains the details of a sensitivity study in which the variation in a commercial aircraft engine's outputs is observed for perturbations in its operating condition inputs or control parameters. This study seeks to determine the extent to which various controller limits can be modified to improve engine performance, while capturing the increased risk that results from the changes. In an emergency, the engine may be required to produce additional thrust, respond faster, or both, to improve the survivability of the aircraft. The objective of this paper is to propose changes to the engine controller and determine the costs and benefits of the additional capabilities produced by the engine. This study indicates that the aircraft engine is capable of producing additional thrust, but at the cost of an increased risk of an engine failure due to higher turbine temperatures and rotor speeds. The engine can also respond more quickly to transient commands, but this action reduces the remaining stall margin to possibly dangerous levels. To improve transient response in landing scenarios, a control mode known as High Speed Idle is proposed that increases the responsiveness of the engine and conserves stall margin

  14. Test and evaluation of the HIDEC engine uptrim algorithm. [Highly Integrated Digital Electronic Control for aircraft

    NASA Technical Reports Server (NTRS)

    Ray, R. J.; Myers, L. P.

    1986-01-01

    The highly integrated digital electronic control (HIDEC) program will demonstrate and evaluate the improvements in performance and mission effectiveness that result from integrated engine-airframe control systems. Performance improvements will result from an adaptive engine stall margin mode, a highly integrated mode that uses the airplane flight conditions and the resulting inlet distortion to continuously compute engine stall margin. When there is excessive stall margin, the engine is uptrimmed for more thrust by increasing engine pressure ratio (EPR). The EPR uptrim logic has been evaluated and implemente into computer simulations. Thrust improvements over 10 percent are predicted for subsonic flight conditions. The EPR uptrim was successfully demonstrated during engine ground tests. Test results verify model predictions at the conditions tested.

  15. A Study on Aircraft Engine Control Systems for Integrated Flight and Propulsion Control

    NASA Astrophysics Data System (ADS)

    Yamane, Hideaki; Matsunaga, Yasushi; Kusakawa, Takeshi

    A flyable FADEC system engineering model incorporating Integrated Flight and Propulsion Control (IFPC) concept is developed for a highly maneuverable aircraft and a fighter-class engine. An overview of the FADEC system and functional assignments for its components such as the Engine Control Unit (ECU) and the Integrated Control Unit (ICU) are described. Overall system reliability analysis, convex analysis and multivariable controller design for the engine, fault detection/redundancy management, and response characteristics of a fuel system are addressed. The engine control performance of the FADEC is demonstrated by hardware-in-the-loop simulation for fast acceleration and thrust transient characteristics.

  16. Integration of On-Line and Off-Line Diagnostic Algorithms for Aircraft Engine Health Management

    NASA Technical Reports Server (NTRS)

    Kobayashi, Takahisa; Simon, Donald L.

    2007-01-01

    This paper investigates the integration of on-line and off-line diagnostic algorithms for aircraft gas turbine engines. The on-line diagnostic algorithm is designed for in-flight fault detection. It continuously monitors engine outputs for anomalous signatures induced by faults. The off-line diagnostic algorithm is designed to track engine health degradation over the lifetime of an engine. It estimates engine health degradation periodically over the course of the engine s life. The estimate generated by the off-line algorithm is used to update the on-line algorithm. Through this integration, the on-line algorithm becomes aware of engine health degradation, and its effectiveness to detect faults can be maintained while the engine continues to degrade. The benefit of this integration is investigated in a simulation environment using a nonlinear engine model.

  17. Polymer, metal, and ceramic matrix composites for advanced aircraft engine applications

    SciTech Connect

    Mc Daniels, D.L.; Serafini, T.T.; Di Carlo, J.A.

    1986-06-01

    Advanced aircraft engine research within NASA Lewis focuses on propulsion systems for subsonic, supersonic, and hypersonic aircraft. Each of these flight regimes requires different types of engines, but all require advanced materials to meet their goals of performance, thrust-to-weight ratio, and fuel efficiency. The high strength/weight and stiffness/weight properties of resin, metal, and ceramic matrix composites will play an increasingly key role in meeting these performance requirements. At NASA Lewis, research is ongoing to apply graphite/polyimide composites to engine components and to develop polymer matrices with higher operating temperature capabilities. Metal matrix composites, using magnesium, aluminum, titanium, and superalloy matrices, are being developed for application to static and rotating engine components, as well as for space applications, over a broad temperature range. Ceramic matrix composites are also being examined to increase the toughness and reliability of ceramics for application to high-temperature engine structures and components.

  18. Computerized systems analysis and optimization of aircraft engine performance, weight, and life cycle costs

    NASA Technical Reports Server (NTRS)

    Fishbach, L. H.

    1980-01-01

    The computational techniques are described which are utilized at Lewis Research Center to determine the optimum propulsion systems for future aircraft applications and to identify system tradeoffs and technology requirements. Cycle performance, and engine weight can be calculated along with costs and installation effects as opposed to fuel consumption alone. Almost any conceivable turbine engine cycle can be studied. These computer codes are: NNEP, WATE, LIFCYC, INSTAL, and POD DRG. Examples are given to illustrate how these computer techniques can be applied to analyze and optimize propulsion system fuel consumption, weight and cost for representative types of aircraft and missions.

  19. Jet engine exhaust emissions of high altitude commercial aircraft projected to 1990

    NASA Technical Reports Server (NTRS)

    Grobman, J.; Ingebo, R. D.

    1974-01-01

    Projected minimum levels of engine exhaust emissions that may be practicably achievable for future commercial aircraft operating at high-altitude cruise conditions are presented. The forecasts are based on:(1) current knowledge of emission characteristics of combustors and augmentors; (2) the status of combustion research in emission reduction technology; and (3) predictable trends in combustion systems and operating conditions as required for projected engine designs that are candidates for advanced subsonic or supersonic commercial aircraft fueled by either JP fuel, liquefied natural gas, or hydrogen. Results are presented for cruise conditions in terms of both an emission index (g constituent/kg fuel) and an emission rate (g constituent/hr).

  20. Sonic IR crack detection of aircraft turbine engine blades with multi-frequency ultrasound excitations

    SciTech Connect

    Zhang, Ding; Han, Xiaoyan; Newaz, Golam

    2014-02-18

    Effectively and accurately detecting cracks or defects in critical engine components, such as turbine engine blades, is very important for aircraft safety. Sonic Infrared (IR) Imaging is such a technology with great potential for these applications. This technology combines ultrasound excitation and IR imaging to identify cracks and flaws in targets. In general, failure of engine components, such as blades, begins with tiny cracks. Since the attenuation of the ultrasound wave propagation in turbine engine blades is small, the efficiency of crack detection in turbine engine blades can be quite high. The authors at Wayne State University have been developing the technology as a reliable tool for the future field use in aircraft engines and engine parts. One part of the development is to use finite element modeling to assist our understanding of effects of different parameters on crack heating while experimentally hard to achieve. The development has been focused with single frequency ultrasound excitation and some results have been presented in a previous conference. We are currently working on multi-frequency excitation models. The study will provide results and insights of the efficiency of different frequency excitation sources to foster the development of the technology for crack detection in aircraft engine components.

  1. 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.

  2. F-15 inlet/engine test techniques and distortion methodologies studies. Volume 2: Time variant data quality analysis plots

    NASA Technical Reports Server (NTRS)

    Stevens, C. H.; Spong, E. D.; Hammock, M. S.

    1978-01-01

    Time variant data quality analysis plots were used to determine if peak distortion data taken from a subscale inlet model can be used to predict peak distortion levels for a full scale flight test vehicle.

  3. The horsepower of aircraft engines and their maximum frontal area

    NASA Technical Reports Server (NTRS)

    Precoul, Michel

    1936-01-01

    This adaptation of a Russian report reveals the effect of maximum cross section of an engine as well as the interest attaching to a choice not solely based on horsepower. The tabulation gives a comparison between different engines restored at 5,000 meters. Radial versus inverted in-line engines are also compared.

  4. Numerical Simulation of Boundary Layer Ingesting (BLI) Inlet-Fan Interaction

    NASA Technical Reports Server (NTRS)

    Giuliani, James; Chen, Jen-Ping; Beach, Timothy; Bakhle, Milind

    2014-01-01

    Future civil transport designs may incorporate engine inlets integrated into the body of the aircraft to take advantage of efficiency increases due to weight and drag reduction. Additional increases in engine efficiency are predicted if the inlet ingests the lower momentum boundary layer flow. Previous studies have shown, however, that efficiency benefits of Boundary Layer Ingesting (BLI) ingestion are very sensitive to the magnitude of fan and duct losses, and blade structural response to the non-uniform flow field that results from a BLI inlet has not been studied in-depth. This paper presents an effort to extend the modeling capabilities of an existing rotating turbomachinery unsteady analysis code to include the ability to solve the external and internal flow fields of a BLI inlet. The TURBO code has been a successful tool in evaluating fan response to flow distortions for traditional engine/inlet integrations, such as the development of rotating stall and inlet distortion through compressor stages. This paper describes the first phase of an effort to extend the TURBO model to calculate the external and inlet flowfield upstream of fan so that accurate pressure distortions that result from BLI configurations can be computed and used to analyze fan aerodynamics and structural response. To validate the TURBO program modifications for the BLI flowfield, experimental test data obtained by NASA for a flushmounted S-duct with large amounts of boundary layer ingestion was modeled. Results for the flow upstream and in the inlet are presented and compared to experimental data for several high Reynolds number flows to validate the modifications to the solver. Quantitative data is presented that indicates good predictive capability of the model in the upstream flow. A representative fan is attached to the inlet and results are presented for the coupled inlet/fan model. The impact on the total pressure distortion at the AIP after the fan is attached is examined.

  5. Air Force F-16 Aircraft Engine Aerosol Emissions Under Cruise Altitude Conditions

    NASA Technical Reports Server (NTRS)

    Anderson, Bruce E.; Cofer, W. Randy, III; McDougal, David S.

    1999-01-01

    Selected results from the June 1997 Third Subsonic Assessment Near-Field Interactions Flight (SNIF-III) Experiment are documented. The primary objectives of the SNIF-III experiment were to determine the partitioning and abundance of sulfur species and to examine the formation and growth of aerosol particles in the exhaust of F-16 aircraft as a function of atmospheric and aircraft operating conditions and fuel sulfur concentration. This information is, in turn, being used to address questions regarding the fate of aircraft fuel sulfur impurities and to evaluate the potential of their oxidation products to perturb aerosol concentrations and surface areas in the upper troposphere. SNIF-III included participation of the Vermont and New Jersey Air National Guard F-16's as source aircraft and the Wallops Flight Facility T-39 Sabreliner as the sampling platform. F-16's were chosen as a source aircraft because they are powered by the modern F-100 Series 220 engine which is projected to be representative of future commercial aircraft engine technology. The T-39 instrument suite included sensors for measuring volatile and non-volatile condensation nuclei (CN), aerosol size distributions over the range from 0.1 to 3.0 (micro)m, 3-D winds, temperature, dewpoint, carbon dioxide (CO2), sulfur dioxide (SO2), sulfuric acid (H2SO4), and nitric acid (HNO3).

  6. Roles, uses, and benefits of general aviation aircraft in aerospace engineering education

    NASA Technical Reports Server (NTRS)

    Odonoghue, Dennis P.; Mcknight, Robert C.

    1994-01-01

    Many colleges and universities throughout the United States offer outstanding programs in aerospace engineering. In addition to the fundamentals of aerodynamics, propulsion, flight dynamics, and air vehicle design, many of the best programs have in the past provided students the opportunity to design and fly airborne experiments on board various types of aircraft. Sadly, however, the number of institutions offering such 'airborne laboratories' has dwindled in recent years. As a result, opportunities for students to apply their classroom knowledge, analytical skills, and engineering judgement to the development and management of flight experiments on an actual aircraft are indeed rare. One major reason for the elimination of flight programs by some institutions, particularly the smaller colleges, is the prohibitive cost of operating and maintaining an aircraft as a flying laboratory. The purpose of this paper is to discuss simple, low-cost, relevant flight experiments that can be performed using readily available general aviation aircraft. This paper examines flight experiments that have been successfully conducted on board the NASA Lewis Research Center's T-34B aircraft, as part of the NASA/AIAA/University Flight Experiment Program for Students (NAUFEPS) and discusses how similar experiments could be inexpensively performed on other general aviation aircraft.

  7. Aircraft Design Considerations to Meet One Engine Inoperative (OEI) Safety Requirements

    NASA Technical Reports Server (NTRS)

    Scott, Mark W.

    2012-01-01

    Commercial airlines are obligated to operate such that an aircraft can suffer an engine failure at any point in its mission and terminate the flight without an accident. Only minimal aircraft damage is allowable, such as brake replacement due to very heavy application, or an engine inspection and/or possible removal due to use of an emergency rating. Such performance criteria are often referred to as zero exposure, referring to zero accident exposure to an engine failure. The critical mission segment for meeting one engine inoperative (OEI) criteria is takeoff. For a given weight, wind, and ambient condition, fixed wing aircraft require a balanced field length. This is the longer of the distance to take off if an engine fails at a predetermined critical point in the takeoff profile, or the distance to reject the takeoff and brake to a stop. Rotorcraft have requirements for horizontal takeoff procedures that are equivalent to a balanced field length requirements for fixed wing aircraft. Rotorcraft also perform vertical procedures where no runway or heliport distance is available. These were developed primarily for elevated heliports as found on oil rigs or rooftops. They are also used for ground level operations as might be found at heliports at the end of piers or other confined areas.

  8. Description and Laboratory Tests of a Roots Type Aircraft Engine Supercharger

    NASA Technical Reports Server (NTRS)

    Ware, Marsden

    1926-01-01

    This report describes a roots type aircraft engine supercharger and presents the results of some tests made with it at the Langley Field Laboratories of the National Advisory Committee for Aeronautics. The supercharger used in these tests was constructed largely of aluminum, weighed 88 pounds and was arranged to be operated from the rear of a standard aircraft engine at a speed of 1 1/2 engine crankshaft speed. The rotors of the supercharger were cycloidal in form and were 11 inches long and 9 1/2 inches in diameter. The displacement of the supercharger was 0.51 cubic feet of air per revolution of the rotors. The supercharger was tested in the laboratory, independently and in combination with a Liberty-12 aircraft engine, under simulated altitude pressure conditions in order to obtain information on its operation and performance. From these tests it seems evident that the Roots blower compares favorably with other compressor types used as aircraft engine superchargers and that it has several features that make it particularly attractive for such use.

  9. A plume capture technique for the remote characterization of aircraft engine emissions.

    PubMed

    Johnson, G R; Mazaheri, M; Ristovski, Z D; Morawska, L

    2008-07-01

    A technique for capturing and analyzing plumes from unmodified aircraft or other combustion sources under real world conditions is described and applied to the task of characterizing plumes from commercial aircraft during the taxiing phase of the Landing/Take-Off (LTO) cycle. The method utilizes a Plume Capture and Analysis System (PCAS) mounted in a four-wheel drive vehicle which is positioned in the airfield 60 to 180 m downwind of aircraft operations. The approach offers low test turnaround times with the ability to complete careful measurements of particle and gaseous emission factors and sequentially scanned particle size distributions without distortion due to plume concentration fluctuations. These measurements can be performed for individual aircraft movements at five minute intervals. A Plume Capture Device (PCD) collected samples of the naturally diluted plume in a 200 L conductive membrane conforming to a defined shape. Samples from over 60 aircraft movements were collected and analyzed in situ for particulate and gaseous concentrations and for particle size distribution using a Scanning Particle Mobility Sizer (SMPS). Emission factors are derived for particle number, NO(x), and PM2.5 for a widely used commercial aircraft type, Boeing 737 airframes with predominantly CFM56 class engines, during taxiing. The practical advantages of the PCAS include the capacity to perform well targeted and controlled emission factor and size distribution measurements using instrumentation with varying response times within an airport facility, in close proximity to aircraft during their normal operations.

  10. Altitude and airspeed effects on the optimum synchrophase angles for a four-engine propeller aircraft

    NASA Astrophysics Data System (ADS)

    Blunt, David M.

    2014-08-01

    Noise and vibration is a serious problem in all types of aircraft. Any techniques that lower cabin noise and vibration levels by even a few decibels with little or no weight or performance penalties are worth pursuing. Propeller synchrophasing is one such technique that has shown potential in aircraft with two or more propellers; however this technique is not being used to its full potential because the synchrophase angles are typically fixed. This paper provides a detailed examination of how the optimum synchrophase angles in a typical four-engine propeller aircraft vary with different altitudes and airspeeds, and how this information could lead to the design of new adaptive propeller synchrophasing systems and potentially yield improvements to other active noise control measures in propeller aircraft.

  11. USAF Aircraft Engine Emission Goals: A Critical Review.

    DTIC Science & Technology

    1979-09-01

    dif- ficult to obtain. Combustion product gases at the exhaust plane are extremely reactive and at high temperature; consequently, much of the CO and...19. KEY WORDS (Continue on reverse side if necessary and identify by block number) J Pollution Abatement Exhaust Emissions Combustion Aircraft...The USAF must continue basic research in areas of combustion , smoke formation, etc. it - -W: (7) Variability of emissions is an area where more

  12. Preliminary Fatigue Studies on Aluminum Alloy Aircraft Engines

    NASA Technical Reports Server (NTRS)

    1938-01-01

    Preliminary information on the complex subject of the fatigue strength of fabricated structural members for aircraft is presented in the test results obtained on several different types of airship girders subjected to axial tension and compression in a resonance fatigue machine. A description of this machine as well as numerous photographs of the fatigue failures are given. There is also presented an extended bibliography on the subject of fatigue strength.

  13. Emergency Multiengine Aircraft System for Lateral Control Using Differential Thrust Control of Wing Engines

    NASA Technical Reports Server (NTRS)

    Burken, John J. (Inventor); Burcham, Frank W., Jr. (Inventor); Bull, John (Inventor)

    2000-01-01

    Development of an emergency flight control system is disclosed for lateral control using only differential engine thrust modulation of multiengine aircraft is currently underway. The multiengine has at least two engines laterally displaced to the left and right from the axis of the aircraft. In response to a heading angle command psi(sub c) is to be tracked. By continually sensing the heading angle psi of the aircraft and computing a heading error signal psi(sub e) as a function of the difference between the heading angle command psi(sub c) and the sensed heading angle psi, a track control signal is developed with compensation as a function of sensed bank angle phi. Bank angle rate phi, or roll rate p, yaw rate tau, and true velocity produce an aircraft thrust control signal ATC(sub psi(L,R)). The thrust control signal is differentially applied to the left and right engines, with equal amplitude and opposite sign, such that a negative sign is applied to the control signal on the side of the aircraft. A turn is required to reduce the error signal until the heading feedback reduces the error to zero.

  14. Design and test of aircraft engine isolators for reduced interior noise

    NASA Technical Reports Server (NTRS)

    Unruh, J. F.; Scheidt, D. C.

    1982-01-01

    Improved engine vibration isolation was proposed to be the most weight and cost efficient retrofit structure-borne noise control measure for single engine general aviation aircraft. A study was carried out the objectives: (1) to develop an engine isolator design specification for reduced interior noise transmission, (2) select/design candidate isolators to meet a 15 dB noise reduction design goal, and (3) carry out a proof of concept evaluation test. Analytical model of the engine, vibration isolators and engine mount structure were coupled to an empirical model of the fuselage for noise transmission evaluation. The model was used to develop engine isolator dynamic properties design specification for reduced noise transmission. Candidate isolators ere chosen from available product literature and retrofit to a test aircraft. A laboratory based test procedure was then developed to simulate engine induced noise transmission in the aircraft for a proof of concept evaluation test. Three candidate isolator configurations were evaluated for reduced structure-borne noise transmission relative to the original equipment isolators.

  15. The Effect of Faster Engine Response on the Lateral Directional Control of a Damaged Aircraft

    NASA Technical Reports Server (NTRS)

    May, Ryan D.; Lemon, Kimberly A.; Csank, Jeffrey T.; Litt, Jonathan S.; Guo, Ten-Huei

    2012-01-01

    The integration of flight control and propulsion control has been a much discussed topic, especially for emergencies where the engines may be able to help stabilize and safely land a damaged aircraft. Previous research has shown that for the engines to be effective as flight control actuators, the response time to throttle commands must be improved. Other work has developed control modes that accept a higher risk of engine failure in exchange for improved engine response during an emergency. In this effort, a nonlinear engine model (the Commercial Modular Aero-Propulsion System Simulation 40k) has been integrated with a nonlinear airframe model (the Generic Transport Model) in order to evaluate the use of enhanced-response engines as alternative yaw rate control effectors. Tests of disturbance rejection and command tracking were used to determine the impact of the engines on the aircraft's dynamical behavior. Three engine control enhancements that improve the response time of the engine were implemented and tested in the integrated simulation. The enhancements were shown to increase the engine s effectiveness as a yaw rate control effector when used in an automatic feedback loop. The improvement is highly dependent upon flight condition; the airframe behavior is markedly improved at low altitude, low speed conditions, and relatively unchanged at high altitude, high speed.

  16. A method to estimate weight and dimensions of small aircraft propulsion gas turbine engines: User's guide

    NASA Technical Reports Server (NTRS)

    Hale, P. L.

    1982-01-01

    The weight and major envelope dimensions of small aircraft propulsion gas turbine engines are estimated. The computerized method, called WATE-S (Weight Analysis of Turbine Engines-Small) is a derivative of the WATE-2 computer code. WATE-S determines the weight of each major component in the engine including compressors, burners, turbines, heat exchangers, nozzles, propellers, and accessories. A preliminary design approach is used where the stress levels, maximum pressures and temperatures, material properties, geometry, stage loading, hub/tip radius ratio, and mechanical overspeed are used to determine the component weights and dimensions. The accuracy of the method is generally better than + or - 10 percent as verified by analysis of four small aircraft propulsion gas turbine engines.

  17. 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.

  18. Effect of NACA Injection Impeller on Mixture Distribution of Double-Row Radial Aircraft Engine

    NASA Technical Reports Server (NTRS)

    Marble, Frank E; Ritter, William K; Miller, Mahlon A

    1945-01-01

    The NACA injection impeller was developed to improve the mixture distribution of aircraft engines by discharging the fuel from a centrifugal supercharger impeller and thus to promote a thorough mixing of fuel and charge air. Experiments with a double-row radial aircraft engine indicated that for the normal range of engine power the NACA injection impeller provided marked improvement in mixture distribution over the standard spray-bar injection system used in the same engine. The mixture distribution at cruising conditions was excellent; at 1200, 1500, and 1700 brake horsepower, the differences between the fuel-air ratios of the richest and the leanest cylinders were reduced to approximately one-third their former values.

  19. Performance degradation of a typical twin engine commuter type aircraft in measured natural icing conditions

    NASA Technical Reports Server (NTRS)

    Ranaudo, R. J.; Mikkelsen, K. L.; Mcknight, R. C.; Perkins, P. J., Jr.

    1984-01-01

    The performance of an aircraft in various measured icing conditions was investigated. Icing parameters such as liquid water content, temperature, cloud droplet sizes and distributions were measured continuously while in icinig. Flight data wre reduced to provide plots of the aircraft drag polars and lift curves (CL vs. alpha) for the measured 'iced' condition as referenced to the uniced aircraft. These data were also reduced to provide plots of thrust horsepower required vs. single engine power available to show how icing affects engine out capability. It is found that performance degradation is primarily influenced by the amount and shape of the accumulated ice. Glaze icing caused the greatest aerodynamic performance penalties in terms of increased drag and reduction in lift while aerodynamic penalties due to rime icing were significantly lower. Previously announced in STAR as N84-13173

  20. Performance degradation of a typical twin engine commuter type aircraft in measured natural icing conditions

    NASA Technical Reports Server (NTRS)

    Ranaudo, R. J.; Mikkelsen, K. L.; Mcknight, R. C.; Perkins, P. J., Jr.

    1984-01-01

    The performance of an aircraft in various measured icing conditions was investigated. Icing parameters such as liquid water content, temperature, cloud droplet sizes and distributions were measured continuously while in icing. Flight data were reduced to provide plots of the aircraft drag polars and lift curves (CL vs. alpha) for the measured ""iced'' condition as referenced to the uniced aircraft. These data were also reduced to provide plots of thrust horsepower required vs. single engine power available to show how icing affects engine out capability. It is found that performance degradation is primarily influenced by the amount and shape of the accumulated ice. Glaze icing caused the greatest aerodynamic performance penalties in terms of increased drag and reduction in lift while aerodynamic penalties due to rime icing were significantly lower.

  1. Status review of NASA programs for reducing aircraft gas turbine engine emissions

    NASA Technical Reports Server (NTRS)

    Rudey, R. A.

    1976-01-01

    Programs initiated by NASA to develop and demonstrate low emission advanced technology combustors for reducing aircraft gas turbine engine pollution are reviewed. Program goals are consistent with urban emission level requirements as specified by the U. S. Environmental Protection Agency and with upper atmosphere cruise emission levels as recommended by the U. S. Climatic Impact Assessment Program and National Research Council. Preliminary tests of advanced technology combustors indicate that significant reductions in all major pollutant emissions should be attainable in present generation aircraft gas turbine engines without adverse effects on fuel consumption. Preliminary test results from fundamental studies indicate that extremely low emission combustion systems may be possible for future generation jet aircraft. The emission reduction techniques currently being evaluated in these programs are described along with the results and a qualitative assessment of development difficulty.

  2. Study of aerodynamic technology for single-cruise-engine V/STOL fighter/attack aircraft

    NASA Technical Reports Server (NTRS)

    Hess, J. R.; Bear, R. L.

    1982-01-01

    A viable, single engine, supersonic V/STOL fighter/attack aircraft concept was defined. This vectored thrust, canard wing configuration utilizes an advanced technology separated flow engine with fan stream burning. The aerodynamic characteristics of this configuration were estimated and performance evaluated. Significant aerodynamic and aerodynamic propulsion interaction uncertainties requiring additional investigation were identified. A wind tunnel model concept and test program to resolve these uncertainties and validate the aerodynamic prediction methods were defined.

  3. An Object-Oriented Computer Code for Aircraft Engine Weight Estimation

    NASA Technical Reports Server (NTRS)

    Tong, Michael T.; Naylor, Bret A.

    2009-01-01

    Reliable engine-weight estimation at the conceptual design stage is critical to the development of new aircraft engines. It helps to identify the best engine concept amongst several candidates. At NASA Glenn Research Center (GRC), the Weight Analysis of Turbine Engines (WATE) computer code, originally developed by Boeing Aircraft, has been used to estimate the engine weight of various conceptual engine designs. The code, written in FORTRAN, was originally developed for NASA in 1979. Since then, substantial improvements have been made to the code to improve the weight calculations for most of the engine components. Most recently, to improve the maintainability and extensibility of WATE, the FORTRAN code has been converted into an object-oriented version. The conversion was done within the NASA's NPSS (Numerical Propulsion System Simulation) framework. This enables WATE to interact seamlessly with the thermodynamic cycle model which provides component flow data such as airflows, temperatures, and pressures, etc., that are required for sizing the components and weight calculations. The tighter integration between the NPSS and WATE would greatly enhance system-level analysis and optimization capabilities. It also would facilitate the enhancement of the WATE code for next-generation aircraft and space propulsion systems. In this paper, the architecture of the object-oriented WATE code (or WATE++) is described. Both the FORTRAN and object-oriented versions of the code are employed to compute the dimensions and weight of a 300-passenger aircraft engine (GE90 class). Both versions of the code produce essentially identical results as should be the case.

  4. Avco Lycoming/NASA contract status. [on reduction of emissions from aircraft piston engines

    NASA Technical Reports Server (NTRS)

    Duke, L. C.

    1976-01-01

    The standards promulgated by the Environmental Protection Agency (EPA) for carbon monoxide (CO), unburned hydrocarbon (HC), and oxides-of-nitrogen (NOx) emissions were the basis in a study of ways to reduce emissions from aircraft piston engines. A variable valve timing system, ultrasonic fuel atomization, and ignition system changes were postulated.

  5. 77 FR 76842 - Exhaust Emissions Standards for New Aircraft Gas Turbine Engines and Identification Plate for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-31

    ... action revises the standards for oxides of nitrogen and test procedures for exhaust emissions based on... Environmental Protection Agency (EPA) proposed new aircraft engine emission standards for oxides of nitrogen (NO... Protection (CAEP) of ICAO uses to differentiate the CAEP work cycles that produce new standards. For...

  6. Weibull-Based Design Methodology for Rotating Aircraft Engine Structures

    NASA Technical Reports Server (NTRS)

    Zaretsky, Erwin; Hendricks, Robert C.; Soditus, Sherry

    2002-01-01

    The NASA Energy Efficient Engine (E(sup 3)-Engine) is used as the basis of a Weibull-based life and reliability analysis. Each component's life and thus the engine's life is defined by high-cycle fatigue (HCF) or low-cycle fatigue (LCF). Knowing the cumulative life distribution of each of the components making up the engine as represented by a Weibull slope is a prerequisite to predicting the life and reliability of the entire engine. As the engine Weibull slope increases, the predicted lives decrease. The predicted engine lives L(sub 5) (95 % probability of survival) of approximately 17,000 and 32,000 hr do correlate with current engine maintenance practices without and with refurbishment. respectively. The individual high pressure turbine (HPT) blade lives necessary to obtain a blade system life L(sub 0.1) (99.9 % probability of survival) of 9000 hr for Weibull slopes of 3, 6 and 9, are 47,391 and 20,652 and 15,658 hr, respectively. For a design life of the HPT disks having probable points of failure equal to or greater than 36,000 hr at a probability of survival of 99.9 %, the predicted disk system life L(sub 0.1) can vary from 9,408 to 24,911 hr.

  7. Pollution reduction technology program small jet aircraft engines, phase 3

    NASA Technical Reports Server (NTRS)

    Bruce, T. W.; Davis, F. G.; Kuhn, T. E.; Mongia, H. C.

    1981-01-01

    A series of Model TFE731-2 engine tests were conducted with the Concept 2 variable geometry airblast fuel injector combustion system installed. The engine was tested to: (1) establish the emission levels over the selected points which comprise the Environmental Protection Agency Landing-Takeoff Cycle; (2) determine engine performance with the combustion system; and (3) evaulate the engine acceleration/deceleration characteristics. The hydrocarbon (HC), carbon monoxide (CO), and smoke goals were met. Oxides of nitrogen (NOx) were above the goal for the same configuration that met the other pollutant goals. The engine and combustor performance, as well as acceleration/deceleration characteristics, were acceptable. The Concept 3 staged combustor system was refined from earlier phase development and subjected to further rig refinement testing. The concept met all of the emissions goals.

  8. Aircraft Engine Sensor/Actuator/Component Fault Diagnosis Using a Bank of Kalman Filters

    NASA Technical Reports Server (NTRS)

    Kobayashi, Takahisa; Simon, Donald L. (Technical Monitor)

    2003-01-01

    In this report, a fault detection and isolation (FDI) system which utilizes a bank of Kalman filters is developed for aircraft engine sensor and actuator FDI in conjunction with the detection of component faults. This FDI approach uses multiple Kalman filters, each of which is designed based on a specific hypothesis for detecting a specific sensor or actuator fault. In the event that a fault does occur, all filters except the one using the correct hypothesis will produce large estimation errors, from which a specific fault is isolated. In the meantime, a set of parameters that indicate engine component performance is estimated for the detection of abrupt degradation. The performance of the FDI system is evaluated against a nonlinear engine simulation for various engine faults at cruise operating conditions. In order to mimic the real engine environment, the nonlinear simulation is executed not only at the nominal, or healthy, condition but also at aged conditions. When the FDI system designed at the healthy condition is applied to an aged engine, the effectiveness of the FDI system is impacted by the mismatch in the engine health condition. Depending on its severity, this mismatch can cause the FDI system to generate incorrect diagnostic results, such as false alarms and missed detections. To partially recover the nominal performance, two approaches, which incorporate information regarding the engine s aging condition in the FDI system, will be discussed and evaluated. The results indicate that the proposed FDI system is promising for reliable diagnostics of aircraft engines.

  9. Validation of Inlet and Exhaust Boundary Conditions for a Cartesian Method

    NASA Technical Reports Server (NTRS)

    Pandya, Shishir A.; Murman, Scott M.; Aftosmis, Michael J.

    2004-01-01

    Inlets and exhaust nozzles are often omitted in aerodynamic simulations of aircraft due to the complexities involved in the modeling of engine details and flow physics. However, the omission is often improper since inlet or plume flows may have a substantial effect on vehicle aerodynamics. A method for modeling the effect of inlets and exhaust plumes using boundary conditions within an inviscid Cartesian flow solver is presented. This approach couples with both CAD systems and legacy geometry to provide an automated tool suitable for parameter studies. The method is validated using two and three-dimensional test problems which are compared with both theoretical and experimental results. The numerical results demonstrate excellent agreement with theory and available data, even for extremely strong jets and very sensitive inlets.

  10. Improved Inlet Noise Attenuation by Alteration of Boundary Layer Profiles

    NASA Technical Reports Server (NTRS)

    Mani, Ramani; Luedke, Jon; Jones, Michael G.; Nark, Douglas M.

    2004-01-01

    Acoustic liners are an essential component of technology used to reduce aircraft engine noise. Flow affects attenuation due to the liner in several ways, one of which is that boundary layers adjacent to the liner refract the sound. In the case of inlet noise, the boundary layer causes sound to be refracted away from the liner, thus degrading attenuation. A concept to improve attenuation by the liner by alteration of inlet boundary layer profiles is presented. The alteration of profiles is achieved by inlet blowing. Computational fluid dynamics and duct mode propagation theory for ducts carrying a parallel sheared flow have been used to design experiments to explore such a possibility in the NASA Langley Research Center Grazing Incidence Tube using an inlet blowing scheme developed at General Electric Global Research. The effects of inlet blowing on two liner configurations were evaluated. Calculated results will be shown for blowing ratios (injected flow/duct flow) of approximately 12% and frequencies up to 3 kHz. These results emphasize changes of attenuation achieved by blowing for the two liners. Experimental results of measured flow profiles (with and without blowing) in the Grazing Incidence Tube, and of corresponding changes in attenuation by the liner due to blowing will be presented.

  11. 75 FR 7947 - Airworthiness Directives; Thielert Aircraft Engines GmbH (TAE) Model TAE 125-01 Reciprocating...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-23

    ... Engines GmbH (TAE) Model TAE 125-01 Reciprocating Engines AGENCY: Federal Aviation Administration (FAA.... The MCAI describes the unsafe condition as: An in-flight engine shutdown incident was reported on an aircraft equipped with a TAE 125-01 engine. This was found to be mainly the result of a blockage of...

  12. Aircraft

    DTIC Science & Technology

    2003-01-01

    national power. But with the recent events such as the war with Iraq, the Severe Acute Respiratory Syndrome (SARS) outbreak, some major carriers... TITLE AND SUBTITLE 2003 Industry Studies: Aircraft 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER

  13. Gaseous Emissions from Aircraft Engines. A Handbook for the Calculation of Emission Indexes and Gaseous Emissions from Aircraft Engines

    DTIC Science & Technology

    1987-09-01

    corresponded to intervals of stable engine operation, as specified by the operators of the engine. Each laboratory reported emission indexes for the read ...period. The test established 50 read periods for gaseous emissions. Tabl, 5-1 gives the emission indexes at idle, high idle, approach, cruise and...emission indexes from a T58-GE-8F engine Test Cell - 12 Location - Naval Air Rework Facility, North Island IDLE Date Time Reading Prior Emission index

  14. Chemical composition and photochemical reactivity of exhaust from aircraft turbine engines

    NASA Astrophysics Data System (ADS)

    Spicer, C. W.; Holdren, M. W.; Riggin, R. M.; Lyon, T. F.

    1994-10-01

    Assessment of the environmental impact of aircraft emissions is required by planners and policy makers. Seveal areas of concern are: 1. exposure of airport workers and urban residents to toxic chemicals emitted when the engines operate at low power (idle and taxi) on the ground; 2. contributions to urban photochemical air pollution of aircraft volatile organic and nitrogen oxides emissions from operations around airports; and 3. emissions of nitrogen oxides and particles during high-altitude operation. The environmental impact of chemicals emitted from jet aircraft turbine engines has not been firmly established due to lack of data regarding emission rates and identities of the compounds emitted. This paper describes an experimental study of two different aircraft turbine engines designed to determine detailed organic emissions, as well as emissions of inorganic gases. Emissions were measured at several engine power settings. Measurements were made of detailed organic composition from C1 through C17, CO, CO2, NO, NOx, and polycyclic aromatic hydrocarbons. Measurements were made using a multi-port sampling pro be positioned directly behind the engine in the exhaust exit plane. The emission measurements have been used to determine the organic distribution by carbon number and the distribution by compound class at each engine power level. The sum of the organic species was compared with an independent measurement of total organic carbon to assess the carbon mass balance. A portion of the exhaust was captured and irradiated in outdoor smog chambers to assess the photochemical reactivity of the emissions with respect to ozone formation. The reactivity of emissions from the two engines was apportioned by chemical compound class.

  15. Variable-cycle engines for supersonic cruise aircraft

    NASA Technical Reports Server (NTRS)

    Willis, E.

    1976-01-01

    Progress and the current status of the Variable Cycle Engine (VCE) study are reviewed with emphasis placed on the impact of technology advancements and design specifications. A large variety of VCE concepts are also examined.

  16. Study of unconventional aircraft engines designed for low energy consumption

    NASA Technical Reports Server (NTRS)

    Neitzel, R. E.; Hirschkron, R.; Johnston, R. P.

    1976-01-01

    A study of unconventional engine cycle concepts, which may offer significantly lower energy consumption than conventional subsonic transport turbofans, is described herein. A number of unconventional engine concepts were identified and parametrically studied to determine their relative fuel-saving potential. Based on results from these studies, regenerative, geared, and variable-boost turbofans, and combinations thereof, were selected along with advanced turboprop cycles for further evaluation and refinement. Preliminary aerodynamic and mechanical designs of these unconventional engine configurations were conducted and mission performance was compared to a conventional, direct-drive turofan reference engine. Consideration is given to the unconventional concepts, and their state of readiness for application. Areas of needed technology advancement are identified.

  17. NASA Now: Engineering Design: Tilt Rotors, Aircraft of the Future

    NASA Video Gallery

    Meet Carl Russell, a research aerospace engineer who is working on developing new innovations for air travel. Russell discusses how tilt rotors work, including a demonstration on how rotors use Ber...

  18. Chemical characterization of the fine particle emissions from commercial aircraft engines during the Aircraft Particle Emissions eXperiment (APEX) 1 to 3

    EPA Science Inventory

    This paper addresses the need for detailed chemical information on the fine particulate matter (PM2.5) generated by commercial aviation engines. The exhaust plumes of nine engine models were sampled during the three test campaigns of the Aircraft Particle Emissions eXperiment (AP...

  19. Optimal Tuner Selection for Kalman-Filter-Based Aircraft Engine Performance Estimation

    NASA Technical Reports Server (NTRS)

    Simon, Donald L.; Garg, Sanjay

    2011-01-01

    An emerging approach in the field of aircraft engine controls and system health management is the inclusion of real-time, onboard models for the inflight estimation of engine performance variations. This technology, typically based on Kalman-filter concepts, enables the estimation of unmeasured engine performance parameters that can be directly utilized by controls, prognostics, and health-management applications. A challenge that complicates this practice is the fact that an aircraft engine s performance is affected by its level of degradation, generally described in terms of unmeasurable health parameters such as efficiencies and flow capacities related to each major engine module. Through Kalman-filter-based estimation techniques, the level of engine performance degradation can be estimated, given that there are at least as many sensors as health parameters to be estimated. However, in an aircraft engine, the number of sensors available is typically less than the number of health parameters, presenting an under-determined estimation problem. A common approach to address this shortcoming is to estimate a subset of the health parameters, referred to as model tuning parameters. The problem/objective is to optimally select the model tuning parameters to minimize Kalman-filterbased estimation error. A tuner selection technique has been developed that specifically addresses the under-determined estimation problem, where there are more unknown parameters than available sensor measurements. A systematic approach is applied to produce a model tuning parameter vector of appropriate dimension to enable estimation by a Kalman filter, while minimizing the estimation error in the parameters of interest. Tuning parameter selection is performed using a multi-variable iterative search routine that seeks to minimize the theoretical mean-squared estimation error of the Kalman filter. This approach can significantly reduce the error in onboard aircraft engine parameter estimation

  20. Experimental Investigation of an Air-Cooled Turbine Operating in a Turbojet Engine at Turbine Inlet Temperatures up to 2500 F

    NASA Technical Reports Server (NTRS)

    Cochran, Reeves P.; Dengler, Robert P.

    1961-01-01

    An experimental investigation was made of an air-cooled turbine at average turbine inlet temperatures up to 2500 F. A modified production-model 12-stage axial-flow-compressor turbojet engine operating in a static sea-level stand was used as the test vehicle. The modifications to the engine consisted of the substitution of special combustor and turbine assemblies and double-walled exhaust ducting for the standard parts of the engine. All of these special parts were air-cooled to withstand the high operating temperatures of the investigation. The air-cooled turbine stator and rotor blades were of the corrugated-insert type. Leading-edge tip caps were installed on the rotor blades to improve leading-edge cooling by diverting the discharge of coolant to regions of lower gas pressure toward the trailing edge of the blade tip. Caps varying in length from 0.15- to 0.55-chord length were used in an attempt to determine the optimum cap length for this blade. The engine was operated over a range of average turbine inlet temperatures from about 1600 to about 2500 F, and a range of average coolant-flow ratios of 0.012 to 0.065. Temperatures of the air-cooled turbine rotor blades were measured at all test conditions by the use of thermocouples and temperature-indicating paints. The results of the investigation indicated that this type of blade is feasible for operation in turbojet engines at the average turbine inlet temperatures and stress levels tested(maximums of 2500 F and 24,000 psi, respectively). An average one-third-span blade temperature of 1300 F could be maintained on 0.35-chord tip cap blades with an average coolant-flow ratio of about 0.022 when the average turbine inlet temperature was 2500 F and cooling-air temperature was about 260 F. All of the leading-edge tip cap lengths improved the cooling of the leading-edge region of the blades, particularly at low average coolant-flow ratios. At high gas temperatures, such parts as the turbine stator and the combustor