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High frequency properties in the unsteady linearised potential flow of a compressible fluid

Published online by Cambridge University Press:  04 July 2016

D. J. Salmond
Affiliation:
Aerodynamics Department, Royal Aircraft Establishment, Farnborough, Hants
F.T. Smith
Affiliation:
Mathematics Department, Imperial College, London

Summary

The unsteady planar flow of inviscid compressible fluid past an oscillating aerofoil is considered. Many recent computational studies have experienced difficulties in obtaining accurate, or any, results at medium or higher frequencies of oscillation. This may well be due to the emergence of multi-scaling and multi-regions according to the present analytical study which concentrates on the large frequency properties of the linearised flowfield. Multi-scaled dependence in the solution is found to occur in both the streamwise and transverse directions. Comparisons are made with computational results.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 1984 

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