WSEAS Transactions on Fluid Mechanics
Print ISSN: 1790-5087, E-ISSN: 2224-347X
Volume 8, 2013
Large Eddy Simulation of Low Subcritical Reynolds NumberFlow across a Rotating Circular Cylinder
Authors: K. Mobini, M. Niazi
Abstract: In this study, unsteady turbulent flow across a counterclockwise rotating circular cylinder is computed using Large Eddy Simulation (LES). The spinratio varies between 0 and 2 and The Reynolds number changes from 3900 to 10000. Time integration of the flow equations is carried out for a very large dimensionless time. Smagorinsky subgrid scale model with Cs=0.1 is used to resolve the residual stresses. Variations of the mean drag and lift coefficients, and the flow structure with spin ratio and Reynolds number are studied. It is found that by increase ofspin ratioor decrease of Reynolds number, both the stagnation point and the wake region move upward along the cylinder. As a result,the mean drag decreases and the mean lift increases. Length of the vortices behindthe cylinder is also increased by increase of bothspin ratio and Reynolds number. The computed results are compared with the results from the other numerical or experimental works, showing a good correspondence. It was found that the LES method is an accurate and convenient method for computation of highly recirculating flows.
Search Articles
Keywords: Large Eddy Simulation, Rotating circular cylinder, unsteady flow, drag coefficient, lift coefficient, subcritical flow