Author: C. F. LoPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Investigation of Adaptive Wall Wind Tunnels with Two Measured Interfaces
Author: C. F. LoA Two-dimensional Adaptive-wall Test Section with Ventilated Walls in the Ames 2- by 2-foot Transonic Wind Tunnel
Author: Adaptive Wall Wind Tunnels
Author: Marie H. TuttlePublisher:
ISBN:
Category : Wind tunnel walls
Languages : en
Pages : 60
Book Description
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.
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.
AGARD Advisory Report
Author: North Atlantic Treaty Organization. Advisory Group for Aerospace Research and DevelopmentPublisher:
ISBN:
Category : Aerodynamics
Languages : en
Pages : 162
Book Description
Adaptive Wall Wind Tunnels
Author: Marie H. TuttlePublisher:
ISBN:
Category : Wind tunnel walls
Languages : en
Pages : 44
Book Description
AIAA 28th Aerospace Sciences Meeting
Author: An Experimental Study of an Adaptive-Wall Wind Tunnel
Author: National Aeronautics and Space Administration (NASA)Publisher: Createspace Independent Publishing Platform
ISBN: 9781722937027
Category :
Languages : en
Pages : 156
Book Description
A series of adaptive wall ventilated wind tunnel experiments was carried out to demonstrate the feasibility of using the side wall pressure distribution as the flow variable for the assessment of compatibility with free air conditions. Iterative and one step convergence methods were applied using the streamwise velocity component, the side wall pressure distribution and the normal velocity component in order to investigate their relative merits. The advantage of using the side wall pressure as the flow variable is to reduce the data taking time which is one the major contributors to the total testing time. In ventilated adaptive wall wind tunnel testing, side wall pressure measurements require simple instrumentation as opposed to the Laser Doppler Velocimetry used to measure the velocity components. In ventilated adaptive wall tunnel testing, influence coefficients are required to determine the pressure corrections in the plenum compartment. Experiments were carried out to evaluate the influence coefficients from side wall pressure distributions, and from streamwise and normal velocity distributions at two control levels. Velocity measurements were made using a two component Laser Doppler Velocimeter system. Celik, Zeki and Roberts, Leonard Unspecified Center FLOW DISTRIBUTION; INFLUENCE COEFFICIENT; PRESSURE DISTRIBUTION; WALL PRESSURE; WIND TUNNEL TESTS; WIND TUNNEL WALLS; CONVERGENCE; FREE FLOW; LIFT; MACH NUMBER; PLENUM CHAMBERS; VELOCITY MEASUREMENT; VENTING...
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