Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 22
Book Description
Adaptive-wall Wind-tunnel Research at NASA-Ames Research Center
Author: Research on Adaptive Wall Wind Tunnels
Author: Robert J. VidalPublisher:
ISBN:
Category : Aerodynamics, Transonic
Languages : en
Pages : 70
Book Description
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.
Recent Years Cooperative Research on Adaptive Wall Wind Tunnel Technology
Author: He JiajuResearch on Adaptive Wall Wind Tunnels
Author: Robert J. VidalPublisher:
ISBN:
Category : Wind tunnel walls
Languages : en
Pages : 63
Book Description
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.
Adaptive Wall Wind Tunnels
Author: Marie H. TuttlePublisher:
ISBN:
Category : Wind tunnel walls
Languages : en
Pages : 60
Book Description
Adaptive Wall Wind Tunnels
Author: Marie H. TuttlePublisher:
ISBN:
Category : Wind tunnel walls
Languages : en
Pages : 44
Book Description
Experiments in a Three-Dimensional Adaptive-Wall Wind Tunnel
Author: National Aeronautics and Space Administration (NASA)Publisher: Createspace Independent Publishing Platform
ISBN: 9781725602434
Category :
Languages : en
Pages : 36
Book Description
Three dimensional adaptive-wall experiments were performed in the Ames Research Center (ARC) 25- by 13-cm indraft wind tunnel. A semispan wing model was mounted to one sidewall of a test section with solid sidewalls, and slotted top and bottom walls. The test section had separate top and bottom plenums which were divided into streamwise and cross-stream compartments. An iterative procedure was demonstrated for measuring wall interference and for adjusting the plenum compartment pressures to eliminate such interference. The experiments were conducted at a freestream Mach number of 0.60 and model angles of attack between 0 and 6 deg. Although in all the experiments wall interference was reduced after the plenum pressures were adjusted, interference could not be completely eliminated. Schairer, E. T. Ames Research Center NASA-TP-2210, A-9255, NAS 1.60:2210 RTOP 505-31-51...
Adaptive-Wall Wind-Tunnel Investigations
Author: J. C Erickson (Jr)Publisher:
ISBN:
Category :
Languages : en
Pages : 83
Book Description
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.
Experiments in a Three-dimensional Adaptive-wall Wind Tunnel
Author: Edward T. SchairerPublisher:
ISBN:
Category : Airplanes
Languages : en
Pages : 40
Book Description
Wind Tunnel Wall Interference (January 1980-May 1988)
Author: Marie H. TuttlePublisher:
ISBN:
Category : Interference (Aerodynamics)
Languages : en
Pages : 96
Book Description