Numerical simulation of flow past a square cylinder with a circular bar upstream and a splitter plate downstream

Abstract

A numerical investigation of flow past a square cylinder with a circular bar upstream and a splitter plate downstream is carried out in this paper by lattice Boltzmann method (LBM). The combination of the three obstacles and LBM is the main novelty of the present study. The flow patterns are analyzed by a uniform flow of Reynolds number 100 based on the side length of the square cylinder, D. Numerical simulations are performed in the range of 1 ≤ Ds/D ≤ 5, 0 ≤ G/D ≤ 7 and 1 ≤ L/D ≤ 6, where Ds, G and L are the center-to center distance, surface-to-surface distance and the splitter plate length, respectively. Six flow patterns are observed in the present study. The maximum percentage reduction in mean drag coefficient is 68.76% at (ds, g, l) = (2.5, 0, 3) which is in pattern VI. The vortex shedding from the square cylinder and the circular bar can be completely suppressed in pattern VI. The small distance between the square cylinder and the splitter plate plays a more vital role in suppression of vortex shedding as compared with large distance and length.