Download or read book An Evaluation of Jet Simulation Parameters for Nozzle Afterbody Testing at Transonic Mach Numbers written by William Lee Peters and published by . This book was released on 1976 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this investigation was to evaluate various jet simulation parameters in an attempt to establish a method of matching hot jet interference with cold jet flows. Successful parameters were determined based on their ability to correlate integrated afterbody pressure drag, a measurement of aerodynamic interference, for jet flows of varying total temperature. Data used in this investigation were obtained from experiments conducted in the AEDC Propulsion Wind Tunnel (16T) with three different isolated nozzle/afterbody configurations at free-stream Mach numbers from 0.6 to 1.5. Gas temperature effects on pressure drag were acquired with a convergent nozzle utilizing an air/ethylene burner to produce gas temperatures from 540 to 3,300 R. In addition, the jet effects of varying internal nozzle geometry, specifically nozzle divergence half-angle and nozzle exit-to-throat area ratio, were investigated utilizing high-pressure air as the nozzle exhaust gas. Jet simulation parameters were evaluated for jet flows where nozzle exit-to-throat area ratio was varied from 1.0 to approximately 1.5 and where divergence half-angle was varied from 0 to 10 deg.
Download or read book An Evaluation of Nozzle Afterbody Code written by Frederick C. Guyton and published by . This book was released on 1986 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA Technical Memorandum written by and published by . This book was released on 1989 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experimental Method for Correcting Nozzle Afterbody Drag for the Effects of Jet Temperature written by W. L. Peters and published by . This book was released on 1981 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this investigation was to isolate those parameters defined as jet mixing effects on afterbody drag in an effort to develop a method of correcting or simulating the effects of jet temperature in wind tunnel experiments. Data used in the investigation were obtained from experiments conducted in the AEDC Aerodynamic Wind Tunnel (1T) with a strut-mounted model at free-stream Mach numbers from 0.6 to 1.2. Integrated afterbody pressure drag coefficient data were acquired for three nozzle area ratios (1.0, 1.24, and 2.96) using various unheated jet exhaust gas compositions that allowed a variation in gas constant from 55 to 767 ft/lbf/lbm-deg R. Jet mixing effects on afterbody drag coefficient produced by varying jet gas constant and nozzle area ratio at nozzle design pressure ratio, and the drag effects resulting from variations in nozzle pressure ratio at certain overexpanded jet conditions were observed to be similar functions of mass flux ratio. A simple experimental method has been proposed to allow corrections of afterbody drag coefficient data obtained in the wind tunnel (using an ambient temperature air jet) for the effects of jet gas constant. By inference, a similar drag correction can be obtained for the combined effect of gas constant and temperature, assuming their product defines the effects on drag produced by variations in either property. (Author).
Download or read book Computation of Axisymmetric Separated Nozzle afterbody Flow written by James L. Jacocks and published by . This book was released on 1980 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: The development of a computer program for solving the compressible, axisymmetric, mass-averaged Navier-Stokes equations is described. The basic numerical algorithm is the MacCormack explicit predictor-corrector scheme. Turbulence modeling is accomplished using an algebraic, two-layer eddy viscosity model with a novel modification dependent on the streamwise gradient of vorticity. Comparisons of computed results with experimental data are presented for several nozzle-afterbody configurations with either or simulated plumes. (Author).
Download or read book Evaluation of Boattail Geometry and Exhaust Plume Temperature Effects on Nozzle Afterbody Drag at Transonic Mach Numbers written by L. L. Galigher and published by . This book was released on 1976 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental program was conducted to investigate the interaction effects which occur between the nozzle exhaust flow and the external flow field associated with isolated nozzle afterbody configurations at transonic Mach numbers. Pressure data were obtained from three afterbody geometries with boattail angles of 10, 15, and 25 deg at Mach numbers from 0.6 to 1.5 at zero angles of attack and sideslip. Cold (High-pressure air) and hot (Air/ethylene combustion) jet test techniques were used to simulate and duplicate, respectively, the nozzle exhaust flow for a sonic jet installation. Nozzle exhaust temperature was varied from 540 to approximately 2,900 R. The most significant results pertain to those effects on boattail pressure drag caused by exhaust plume temperature and flow asymmetry (Model support strut induced). The differences obtained in boattail pressure drag between the cold jet simulation and hot jet duplication results were significant at nozzle pressure ratios representative for turbofan and turbojet engines at subsonic Mach numbers. Adjusting the cold jet nozzle pressure ratio to correct for changes in the exhaust plume specific heat ratio with temperature did not account for the differences observed. Flow asymmetry effects were Mach number and nozzle pressure ratio dependent and increased in severity as the boattail angle was increased.
Download or read book A Parametric Investigation of the Annular Jet Concept for Obtaining Afterbody Drag Data at Transonic Mach Numbers written by Earl A. Price (Jr.) and published by . This book was released on 1978 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evaluation of Reynolds Number and Tunnel Wall Porosity Effects on Nozzle Afterbody Drag at Transonic Mach Numbers written by C. E. Robinson and published by . This book was released on 1976 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental investigation was conducted to study the effects of Reynolds number variation on isolated nozzle afterbody performance. A strut-mounted cone-cylinder model with three separate afterbody configurations for Aerospace Research and Development (AGARD) was used for this investigation. This program was conducted in two phases distinguished by the model size and the wind tunnels used to obtain the experimental results. The effect of tunnel wall porosity on nozzle afterbody (NAB) performance was investigated.
Download or read book Journal of Aircraft written by and published by . This book was released on 1998 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Jet Simulation Techniques written by W. L. Peters and published by . This book was released on 1979 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this investigation was to evaluate the effects of individual jet exhaust properties on afterbody drag coefficient and to determine whether these properties affect drag by primarily altering the jet plume shape and/or jet entrainment. A large reduction in afterbody drag coefficient was observed with a decrease in the specific heat ratio at most underexpanded nozzle flow conditions. Regardless of free-stream Mach number of afterbody external configuration, an increase in the gas constant produced a consistent reduction in afterbody drag coefficient that was not a function of nozzle pressure ratio. The effects of gas constant increased for separated afterbody configurations and at transonic free-stream Mach numbers. From analysis of the experimental data, it was concluded that the effects of gas constant and specific heat ratio were, to a large extent separate, that the gas constant affected afterbody drag solely through the extrainment or mixing process, and that the specific heat ratio affected the drag primarily through determination of the inviscid jet plume shape.
Download or read book AIAA 85 1455 AIAA 85 1484 With omissions in numbering written by and published by . This book was released on 1985 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA Scientific and Technical Publications written by and published by . This book was released on 1993 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Selected Library Acquisitions written by United States. Department of Transportation and published by . This book was released on with total page 460 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA SP written by and published by . This book was released on 1986 with total page 544 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Journal of the Aeronautical Society of India written by Aeronautical Society of India and published by . This book was released on 1999 with total page 316 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 1977 with total page 660 pages. Available in PDF, EPUB and Kindle. Book excerpt:
