Determination of Optimum Operating Parameters for the AEDC-PWT 4-Ft Transonic Tunnel with Variable Porosity Test Section Walls

Abstract

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Evaluation on Interference Effects on a Lifting Model in the AEDC-PWT 4- Ft Transonic Tunnel

“…AEDC-TR-70-72 4.5 BLOCKAGE EFFECTS * * 4 Data are presented in Ref. 4 which demonstrate significant subsonic blockage interference with a 1-percent blockage model at low wall porosities. Unpublished data have since been obtained with a 1.…”

“…Experimental supersonic static-pressure distributions on a 20-deg cone-cylinder model in Tunnel 4T with variable wall porosity are given in Ref. 4. In general, the data are subject to wave reflection interference from the tunnel walls, there being a unique wall porosity required for wave cancellation at each Mach number.…”

Streamwise porosity distribution optimization for minimising wall interference in a transonic wind tunnel

“…An optimized and non-uniform porosity distribution along the test section centerline instead of an uniform value can be used in order to maximize the reduction of the wall interference over the widest possible Mach number range 1,2,3,4 .…”