Three-dimensional wavelet multiresolution analysis of flow structures behind a vehicle external mirror

Abstract

The three-dimensional orthogonal wavelet multi-resolution technique was applied to analyze flow structures of various scales around an externally mounted vehicle mirror. Firstly, three-dimensional flow of the mirror wake was numerically analyzed by using the large eddy simulation (LES). Then, the instantaneous velocity and vorticity were decomposed into the large-, intermediate-,and relatively small-scale components by the wavelet multi-resolution technique. It was found that a three-dimensional large-scale vertical vortex dominates the mirror wake flow and makes a main contribution to vorticity. Some intermediate-and relatively small-scale vortices were extracted and were clearly identifiable.