Download or read book Advanced Subsonic Technology Area of Interest written by National Aeronautics and Space Administration and published by . This book was released on 2018-08-27 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt: AlliedSignal Engines, in cooperation with NASA GRC (National Aeronautics and Space Administration Glenn Research Center), completed an evaluation of recently-developed aeroelastic computer codes using test cases from the AlliedSignal Engines fan blisk and turbine databases. Test data included strain gage, performance, and steady-state pressure information obtained for conditions where synchronous or flutter vibratory conditions were found to occur. Aeroelastic codes evaluated included quasi 3-D UNSFLO (MIT Developed/AE Modified, Quasi 3-D Aeroelastic Computer Code), 2-D FREPS (NASA-Developed Forced Response Prediction System Aeroelastic Computer Code), and 3-D TURBO-AE (NASA/Mississippi State University Developed 3-D Aeroelastic Computer Code). Unsteady pressure predictions for the turbine test case were used to evaluate the forced response prediction capabilities of each of the three aeroelastic codes. Additionally, one of the fan flutter cases was evaluated using TURBO-AE. The UNSFLO and FREPS evaluation predictions showed good agreement with the experimental test data trends, but quantitative improvements are needed. UNSFLO over-predicted turbine blade response reductions, while FREPS under-predicted them. The inviscid TURBO-AE turbine analysis predicted no discernible blade response reduction, indicating the necessity of including viscous effects for this test case. For the TURBO-AE fan blisk test case, significant effort was expended getting the viscous version of the code to give converged steady flow solutions for the transonic flow conditions. Once converged, the steady solutions provided an excellent match with test data and the calibrated DAWES (AlliedSignal 3-D Viscous Steady Flow CFD Solver). However, efforts expended establishing quality steady-state solutions prevented exercising the unsteady portion of the TURBO-AE code during the present program. AlliedSignal recommends that unsteady pressure measurement data be obtained for both test cases examined ...
Download or read book Advanced Subsonic Technology AST Area of Interest AOI 6 Develop and Validate Aeroelastic Codes for Turbomachinery written by and published by . This book was released on 1999 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advanced Subsonic Technology AST Area of Interest AOI 6 written by and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Application of Aeroelastic Solvers Based on Navier Stokes Equations written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-05-29 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: The propulsion element of the NASA Advanced Subsonic Technology (AST) initiative is directed towards increasing the overall efficiency of current aircraft engines. This effort requires an increase in the efficiency of various components, such as fans, compressors, turbines etc. Improvement in engine efficiency can be accomplished through the use of lighter materials, larger diameter fans and/or higher-pressure ratio compressors. However, each of these has the potential to result in aeroelastic problems such as flutter or forced response. To address the aeroelastic problems, the Structural Dynamics Branch of NASA Glenn has been involved in the development of numerical capabilities for analyzing the aeroelastic stability characteristics and forced response of wide chord fans, multi-stage compressors and turbines. In order to design an engine to safely perform a set of desired tasks, accurate information of the stresses on the blade during the entire cycle of blade motion is required. This requirement in turn demands that accurate knowledge of steady and unsteady blade loading is available. To obtain the steady and unsteady aerodynamic forces for the complex flows around the engine components, for the flow regimes encountered by the rotor, an advanced compressible Navier-Stokes solver is required. A finite volume based Navier-Stokes solver has been developed at Mississippi State University (MSU) for solving the flow field around multistage rotors. The focus of the current research effort, under NASA Cooperative Agreement NCC3- 596 was on developing an aeroelastic analysis code (entitled TURBO-AE) based on the Navier-Stokes solver developed by MSU. The TURBO-AE code has been developed for flutter analysis of turbomachine components and delivered to NASA and its industry partners. The code has been verified. validated and is being applied by NASA Glenn and by aircraft engine manufacturers to analyze the aeroelastic stability characteristics of modem fans, compressors and
Download or read book Linflux Ae written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-03 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes the development and validation of LINFLUX-AE, a turbomachinery aeroelastic code based on the linearized unsteady 3-D Euler solver, LINFLUX. A helical fan with flat plate geometry is selected as the test case for numerical validation. The steady solution required by LINFLUX is obtained from the nonlinear Euler/Navier Stokes solver TURBO-AE. The report briefly describes the salient features of LINFLUX and the details of the aeroelastic extension. The aeroelastic formulation is based on a modal approach. An eigenvalue formulation is used for flutter analysis. The unsteady aerodynamic forces required for flutter are obtained by running LINFLUX for each mode, interblade phase angle and frequency of interest. The unsteady aerodynamic forces for forced response analysis are obtained from LINFLUX for the prescribed excitation, interblade phase angle, and frequency. The forced response amplitude is calculated from the modal summation of the generalized displacements. The unsteady pressures, work done per cycle, eigenvalues and forced response amplitudes obtained from LINFLUX are compared with those obtained from LINSUB, TURBO-AE, ASTROP2, and ANSYS.Reddy, T. S. R. and Bakhle, M. A. and Trudell, J. J. and Mehmed, O. and Stefko, G. L.Glenn Research CenterAEROELASTICITY; TURBOMACHINERY; UNSTEADY AERODYNAMICS; FLUTTER; FLUTTER ANALYSIS; AERODYNAMIC FORCES; EIGENVALUES; EXCITATION; NONLINEARITY
Download or read book Ast Critical Propulsion and Noise Reduction Technologies for Future Commercial Subsonic Engines Area of Interest 1 0 written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-27 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt: The General Electric Reliable and Affordable Controls effort under the NASA Advanced Subsonic Technology (AST) Program has designed, fabricated, and tested advanced controls hardware and software to reduce emissions and improve engine safety and reliability. The original effort consisted of four elements: 1) a Hydraulic Multiplexer; 2) Active Combustor Control; 3) a Variable Displacement Vane Pump (VDVP); and 4) Intelligent Engine Control. The VDVP and Intelligent Engine Control elements were cancelled due to funding constraints and are reported here only to the state they progressed. The Hydraulic Multiplexing element developed and tested a prototype which improves reliability by combining the functionality of up to 16 solenoids and servo-valves into one component with a single electrically powered force motor. The Active Combustor Control element developed intelligent staging and control strategies for low emission combustors. This included development and tests of a Controlled Pressure Fuel Nozzle for fuel sequencing, a Fuel Multiplexer for individual fuel cup metering, and model-based control logic. Both the Hydraulic Multiplexer and Controlled Pressure Fuel Nozzle system were cleared for engine test. The Fuel Multiplexer was cleared for combustor rig test which must be followed by an engine test to achieve full maturation. Myers, William and Winter, Steve Glenn Research Center NAS3-27720; WBS 22-714-20-20...
Download or read book Advanced Aeroelastic Technologies for Turbomachinery Application written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-15 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: A summary of the work performed under the grant NCC-1068 is presented. More details can be found in the cited references. The summary is presented in two parts to represent two areas of research. In the first part, methods to analyze a high temperature ceramic guide vane subjected to cooling jets are presented, and in the second part, the effect of unsteady aerodynamic forces on aeroelastic stability as implemented into the turbo-REDUCE code are presented DeWitt, Kenneth and Srivastava, Rakesh and Reddy, T. S. R. Glenn Research Center NCC3-1068
Download or read book Advanced Supersonic Technology Concept AST 100 Characteristics Developed in a Baseline update Study written by and published by . This book was released on 1976 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development of a Turbomachinery Aeroelastic Code Based on a 3D Linearized Euler Solver written by T. S. R. Reddy and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book AGARD Manual on Aeroelasticity in Axial flow Turbomachines Structural dynamics and aeroelasticity written by Max F. Platzer and published by . This book was released on 1987 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first volume of this Manual reviewed the state of the art of unsteady turbomachinery aerodynamics as required for the study of aeroelasticity in axial turbomachines. This second volume aims to complete the review by presenting the state of the art of structural dynamics and of aeroelasticity. The eleven chapters in this second volume give an overview of the subject and reviews of the structural dynamics characteristics and analysis methods applicable to single blades and bladed assemblies. The blade fatigue problem and its assessment methods, and life-time prediction are considered. Aeroelastic topics covered: the problem of blade-disc shroud aeroelastic coupling, formulations and solutions for tuned and mistuned rotors, and instrumentation on test procedures to perform a fan flutter test. The Effect of stagnation temperature and pressure on flutter is demonstrated and currently available forced vibration and flutter design methodology is reviewed.
Download or read book The Cambridge Aerospace Dictionary written by Bill Gunston and published by Cambridge University Press. This book was released on 2011-02-14 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Cambridge Aerospace Dictionary is an authoritative and accessible reference useful to scholars and enthusiasts alike. This dictionary is an essential tool for professionals involved in the aerospace industry and flight, and for anyone who must read and understand the technical literature of the aerospace industry and about specific air and space craft. It is also an ideal reference for engineering and physics students encountering a subject replete with technical jargon and acronyms. Bill Gunston, one of the most widely read and respected aviation writers, has added more than 5,000 new terms and acronyms to this carefully updated volume. Terms used in the dictionary reflect the diverse and international nature of the aerospace industry and include brief explanations of aerospace materials and organizations. Gunston has scrupulously avoided terms specific to manufacturers, airlines, and armed forces in an effort to encourage clear communication and understanding among professionals.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1991 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Announcements Index written by and published by . This book was released on 1988 with total page 1132 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Major Research Topics in Combustion written by M.Y. Hussaini and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 668 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Institute for Computer Applications in Science and Engineer ing (ICASE) and NASA Langley Research Center (LaRC) brought together on October 2-4, 1989 experts in the various areas of com bustion with a view to expose them to some combustion problems of technological interest to LaRC and possibly foster interaction with the academic community in these research areas. The top ics chosen for this purpose were flame structure, flame stability, flame holding/extinction, chemical kinetics, turbulence-kinetics in teraction, transition to detonation, and reacting free shear layers. The lead paper set the stage by discussing the status and issues of supersonic combustion relevant to scramjet engine. Then the ex perts were called upon i) to review the current status of knowledge in the aforementioned ;:I. reas, ii) to focus on how this knowledge can be extended and applied to high-speed combustion, and iii) to suggest future directions of research in these areas. Each topic was then dealt with in a position paper followed by formal discussion papers and a general discussion involving the participants. The position papers discussed the state-of-the-art with an emphasis on key issues that needed to be resolved in the near future. The discussion papers crit ically examined these issues and filled in any lacunae therein. The edited versions of the general discussions in the form of questions from the audience and answers from the speakers are included wher ever possible to give the reader the flavor of the lively interactions that took place.
Download or read book UMTA CA written by and published by . This book was released on 1980 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cities and Their Vital Systems written by Advisory Committee on Technology and Society and published by National Academies Press. This book was released on 1989 with total page 1298 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cities and Their Vital Systems asks basic questions about the longevity, utility, and nature of urban infrastructures; analyzes how they grow, interact, and change; and asks how, when, and at what cost they should be replaced. Among the topics discussed are problems arising from increasing air travel and airport congestion; the adequacy of water supplies and waste treatment; the impact of new technologies on construction; urban real estate values; and the field of "telematics," the combination of computers and telecommunications that makes money machines and national newspapers possible.
Download or read book Bird Hazards to Aircraft written by H. Blokpoel and published by Clarke Irwin ; [Ottawa] : Canadian Wildlife Service, Environment Canada : Pub. Centre, Supply and Services Canada. This book was released on 1976 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt:
