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Homogeneous wall boundary condition for oscillatory flow in slotted tunnels

Published online by Cambridge University Press:  04 July 2016

D.G. Mabey
D.G. Mabey*
Affiliation:
Formerly DRA Bedford, Imperial College, London
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Abstract

The aerodynamic interference between oscillating models and the walls of slotted windtunnels is controlled by the homogeneous wall boundary condition, which has hitherto been uncertain. In this report a new homogeneous boundary condition for slotted tunnels is suggested which incorporates the important effects of plenum chamber depth and slot parameter.

In particular, this new boundary condition controls the transverse resonance frequencies of the tunnel, which represent a severe form of wall interference. Hence a comparison of measured resonance frequencies with predictions based on such a boundary condition provides a good test of its correctness.

The new homogeneous boundary condition complements that obtained previously for a perforated tunnel and is essentially similar in character. The boundary condition is applicable to oscillatory flows at frequencies ranging from quasi-steady values to multiples of the first resonance frequency.

Type
Research Article
Information
The Aeronautical Journal , Volume 101 , Issue 1003 , March 1997 , pp. 99 - 110
Copyright
Copyright © Royal Aeronautical Society 1997 

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