Approximate Coordinate Transformations for Simulation of Turbulent Flows with Active Wall Motions

Title & Authors
Approximate Coordinate Transformations for Simulation of Turbulent Flows with Active Wall Motions
Gang, Sang-Mo;

Abstract
In the present paper, approximate coordinate transformations for simulation of turbulent flows with active wall motions, leading to a significant reduction in the computational cost while maintaining the numerical accuracy, are presented: the Navier-Stokes equations are coordinate-transformed with an approximation of Taylor-series truncation and neglect of some less-significant terms. The performance of the proposed transformations is evaluated in simulation of the channel flow at Re$\small{\sub}$$\small{\tau}$/=140 with wall deformations of │η$\small{\sub}$m/$\small{\^}$+/ 5. The approximate transformations provide flow structures as wall as turbulence statistics in good agreement with those from a complete coordinate transformation [Phys. Fluids 12, 3301 (2000)] and allow 25-30% savings in the CPU time as compared to the complete one.
Keywords
Turbulence Control;Drag Reduction;Active Wall Motion;Approximate Coordinate Transformation;
Language
Korean
Cited by
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