Three–dimensional flow near surface distortions for the compensation regime

Abstract

Flow past an isolated, small, three–dimensional roughness located on a plate is investigated theoretically and numerically. Depending on roughness scales, there are different local disturbed flow regimes. The so–called ‘compensation regime’ is characterized by conservation of boundary–layer thickness for which the flow near the roughness does not interact with the external inviscid flow. A spectral numerical method is used to calculate the corresponding three–dimensional boundary problem.