Download or read book Methods for Assessing Wall Interference in the 2 by 2 foot Adaptive wall Wind Tunnel written by and published by . This book was released on 1986 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Two Dimensional Adaptive Wall Test Section with Ventilated Walls in the Ames 2 By 2 Foot Transonic Wind Tunnel written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-02 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first tests conducted in the adaptive-wall test section of the Ames Research Center's 2- by 2-Foot Transonic Wind Tunnel are described. A procedure was demonstrated for reducing wall interference in transonic flow past a two-dimensional airfoil by actively controlling flow through the slotted walls of the test section. Flow through the walls was controlled by adjusting pressures in compartments of plenums above and below the test section. Wall interference was assessed by measuring (with a laser velocimeter) velocity distributions along a contour surrounding the model, and then checking those measurements for their compatibility with free-air far-field boundary conditions. Plenum pressures for minimum wall interference were determined from empirical influence coefficients. An NACA 0012 airfoil was tested at angles of attach of 0 and 2, and at Mach numbers between 0.70 and 0.85. In all cases the wall-setting procedure greatly reduced wall interference. Wall interference, however, was never completely eliminated, primarily because the effect of plenum pressure changes on the velocities along the contour could not be accurately predicted. Schairer, Edward T. and Lee, George and Mcdevitt, T. Kevin Ames Research Center...
Download or read book Adaptive Wall Wind Tunnel Investigations written by J. C Erickson (Jr) and published by . This book was released on 1981 with total page 83 pages. Available in PDF, EPUB and Kindle. Book excerpt: The results of a program of research on transonic wind tunnels with adaptive walls for eliminating wall interference are presented. A description is given of related experimental research performed at other laboratories using several alternative methods for controlling the flow. Features of the segmented- plenum, perforated-wall, two-dimensional test section of the Calspan One-Foot Tunnel and the associated instrumentation for measuring the flow disturbance quantities are reviewed and necessary modifications made to the original experimental configuration are described. Details of adaptive-wall iteration experiments with a 4%-blockage NACA 0012 airfoil model are presented, particularly those at a free-stream Mach number of 0.9 and nominal angles of attack of 3, 2 and 1 deg. In these experiments, regions of supercritical flow terminated by shock waves extended to the tunnel walls. The results of the experiments indicate that successful iterations toward interference-free flow conditions are achieved. For another phase of the research, conceptual design studies of a three-dimensional transonic adaptive-wall test section using the segmented-plenum, perforated-wall method of flow control are reported. Finally, numerical simulations of low-speed flow within the Calspan test section, including the interaction of the transpired boundary layer at the walls with the flow over the model, are described in AIAA Paper No. 81-0160, which is appended to the report.
Download or read book Wind Tunnel Wall Interference January 1980 May 1988 written by Marie H. Tuttle and published by . This book was released on 1988 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Residual Interference Assessment in Adaptive Wall Wind Tunnels written by and published by . This book was released on 1989 with total page 34 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 464 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Research on Adaptive Wall Wind Tunnels written by Robert J. Vidal and published by . This book was released on 1978 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this research was to investigate the utility of the Calspan self-correcting wind tunnel for minimizing or eliminating wall interference effects in two-dimensional transonic flows when shock waves from the test model extend to the tunnel walls. This report summarizes the experimental research performed with two-dimensional airfoils in the Calspan self-correcting wind tunnel and the theoretical research accomplished in support of the experiments. The experiments were performed with airfoil models having 4% and 6% solid blockage. The initial experiments with the 6%-blockage model were devoted to determining a practical mode of operation when shock waves from the model extend to the wall. The most practical model is to use wall control to obtain the desired distribution of longitudinal velocity components for subcritical walls. The Mach number is then increased and the wall control is readjusted, sequentially, until the desired test condition is achieved. At the high Mach numbers of interest, however, the available wall control was limited locally, and tunnel system changes were required. A method is reported for analyzing self-correcting wind tunnels with porous walls.
Download or read book A Two dimensional Adaptive wall Test Section with Ventilated Walls in the Ames 2 by 2 foot Transonic Wind Tunnel written by and published by . This book was released on 1989 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aerodynamics And Aeroacoustics Proceedings Of The Symposium written by Fung K Y and published by World Scientific. This book was released on 1994-04-19 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aim of the symposium was to gather fellow researchers, colleagues and friends of Professor William R Sears, a member of the National Academy of Science and the Academy of Engineering, on the occasion of his 80th birthday. Professor Sears is a leader in Aerospace Science and Aerodynamics research and the symposium was held in honour of his work in these areas.The symposium focussed on four areas in aeronautical science in which Professor Sears has made major contributions. These are wing design, unsteady aerodynamics and separation, aeroacoustics and self-correcting wind tunnels.
Download or read book Two dimensional Wind Tunnel Wall Interference written by M. Mokry and published by . This book was released on 1983 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt: A description and analysis is presented of the more important developments during the past decade in the understanding of the wall interference problem associated with two-dimensional wind tunnel testing at subsonic and transonic speeds. Discussed are: wall boundary conditions; asymptotic analysis of wall interference; classical and extended wall interference theories; wall interference corrections from boundary measurements; integral equation formulation of subcritical wall interference; and effects of side wall boundary layer on two-dimensional tests. Unsteady wall interference at subsonic flow conditions is reviewed. Recent advances in the adaptive wall technique, which actively reduces or eliminates wall interference, are also described. (Author).
Download or read book Wind Tunnel Wall Interference Assessment correction 1983 written by Perry A. Newman and published by . This book was released on 1984 with total page 440 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Residual Interference Assessment in Adaptive Wall Wind Tunnels written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-11 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: A two-variable method is presented which is suitable for on-line calculation of residual interference in airfoil testing in the Langley 0.3-Meter Transonic Cryogenic Tunnel (0.3-M TCT). The method applies the Cauchy's integral formula to the closed contour formed by the contoured top and bottom walls, and the upstream and downstream ends. The measured top and bottom wall pressures and position are used to calculate the correction to the test Mach number and the airfoil angle of attack. Application to specific data obtained in the 0.3-M TCT adaptive wall test section demonstrates the need to assess residual interference to ensure that the desired level of wall streamlining is achieved. A FORTRAN computer program was developed for on-line calculation of the residual corrections during airfoil tests in the 0.3-M TCT. Murthy, A. V. Unspecified Center NAS1-18585; RTOP 505-61-01-09...
Download or read book NASA Technical Memorandum written by and published by . This book was released on 1986 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Recent Advances in Aerodynamics written by Anjaneyulu Krothapalli and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 752 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Joint Institute for Aeronautics and Acoustics at Stanford University was established in October 1973 to provide an academic environment for long-term cooperative research between Stanford and NASA Ames Research Center. Since its establishment, the In stitute has wnducted theoretical and experimental work in the areas of aerodynamics, acoustics, fluid mechanics, flight dynamics, guid ance and control, and human factors. This research has involved Stanford faculty, research associates, graduate students, and many distinguished visitors in collaborative efforts with the research staff of NASA Ames Research Center. The occasion of the Institute's tenth anniversary was used to reflect back on where that research has brought us, and to consider where our endeavors should be directed next. Thus, an International Symposium was held to review recent advances in the fields relevant to the activities of the Institute and to discuss the areas of research to be undertaken in the future. This anniversary was also chosen a.."1 an opportunity to honor one of the Institute's founders and its di rector, Professor Krishnamurty Karamcheti. It has been his creative inspiration that has provided the ideal research environment at the Joint Institute. The International Symposium on Recent Advances in Aero dynamics and Aconstics was held at Stanford University, Stanford, California, U.S.A., August 22-26, 198:~. Thirty-five distinguished scientists were invited to present a comprehensive review on the fol lowing subject areas: unsteady aerodynamics, jets and shear layers, V /STOL aircraft aerodynamics, rotor dynamics and aerodynamics,.
Download or read book Technical Evaluation Report on Fluid Dynamics Panel Specialists Meeting on Wall Interference in Wind Tunnels written by Travis W Binion (Jr) and published by . This book was released on 1983 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Fluid Dynamics Panel has been concerned with stimulating activity to understand and quantify the effects of wind tunnel wall interference. Many research endeavors have been undertaken to lean how to correct wind tunnel data or to reduce the wall induced interference. Successful efforts have been largely limited to solid wall, low speed situations. The invention of ventilated wall tunnels did much to reduce the tunnel boundary induced interferences. The adaptive wall concept promises to finally provide a test environment with negligible wall interference. The primary purpose of this meeting was to review and assess the current status of wall interference correction methods and adaptive wall research in three sessions: Solid Wall Wind Tunnels, Ventilated Wall Wind Tunnels, Adaptive Wall Wind Tunnels.
Download or read book Monthly Catalogue United States Public Documents written by and published by . This book was released on 1991-05 with total page 1346 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Monthly Catalog of United States Government Publications written by and published by . This book was released on 1991 with total page 780 pages. Available in PDF, EPUB and Kindle. Book excerpt: