Affiliation:
1. China University of Petroleum
Abstract
Origins of coherent structures near wall of a turbulent boundary layer has been studied by direct numerical simulation (DNS). Forming mechanism of coherent structures agrees well with DNS results. A close relationship has been found between the evolutional characteristics and factors such as the magnitude and structural distribution of the wall local impulse, and the amount of energy and the length of loading time that the initial local impulse disturbance introduces into the wall region. Moreover, these parameters play key roles in the formation of coherent structures near wall of a turbulent boundary layer. So, the wall local impulse disturbance provides the origins for inducing the formation of coherent structures in wall region of a turbulent boundary layer.
Publisher
Trans Tech Publications, Ltd.
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