Large eddy simulation of a circular cylinder mounted with barchan dune-shaped vortex generators

Abstract

This study explores the performance of barchan dune-shaped vortex generators (BDVGs) as a passive flow control device on a circular cylinder at a Reynolds number of 3900. Using large eddy simulations (LES), the flow field around the cylinder, with BDVGs mounted symmetrically on its upper and lower surfaces, is analyzed. Two geometric configurations of BDVGs—slender (type I) and stubby (type II)—are compared to assess their effects on drag and lift coefficients across varying installation heights. The results demonstrate that BDVGs effectively reduce both the drag coefficient and the amplitude of aerodynamic force fluctuations. Notably, type II BDVGs outperform type I, achieving a maximum drag reduction of 6.17 %. Furthermore, BDVGs decrease the maximum amplitude of lift coefficient oscillations to 35.37 % of that observed for a smooth cylinder. These findings underscore the potential of BDVGs as practical and efficient solutions for aerodynamic flow control.