TITLE:
Dimensional Analysis and Dissipation Rate Estimation in the Near Wake of a Circular Cylinder
AUTHORS:
Xintai Zhang, Wei Wei Zhong, Jiangzhi Yang, Minghou Liu
KEYWORDS:
Cylinder, Near Wake, Large Eddy PIV, Dissipation Rate
JOURNAL NAME:
Journal of Applied Mathematics and Physics,
Vol.2 No.6,
May
19,
2014
ABSTRACT: A particle image velocimetry (PIV)
experiment is performed for dissipation rate estimation in the near wake behind
a circular cylinder with diameter D of 12 mm and corresponding Reynolds number
of 7100. Considering the limitation of PIV resolution, a large eddy PIV method
based on idea of large eddy simulation (LES), is used for more accurate estimation
of dissipation rate. Based on the dynamic equilibrium assumption in the
inertial subrange, the dissipation rate of the subgrid scales is approximated
by the subgrid scale (SGS) flux, computed from PIV velocity fields and Smagorinsky
model for SGS stress. A dimensional analysis about the integral length scale
and the Kolmogorov length scale is discussed firstly to verify whether the
dynamic equilibrium assumption holds or not.