Flow characteristics around four circular cylinders in equispaced arrangement near a plane wall

The flow characteristics around four circular cylinders in equispaced arrangement located near a plane wall were investigated experimentally. The pressure distributions on the each cylinder surface and on the plane wall were measured for a spacing ratio L/D= 1.5 (L, center to center spacing between cylinders; D, diameter) and G/D= 0.2 (G, gap spacing between cylinder surface and the plane wall) in a uniform flow at a Reynolds Number of 5.3 × 10⁴. The 2D U-RANS numerical simulation with k-ω SST as viscous model was used to visualize the flow phenomena occured around the cylinders. The results showed that the flow tend to be biased on the upper side of cylinders configuration. It causes the stagnation at the upstream cylinders occured at lower side of cylinders and results a formation of a narrower wake behind the third cylinder and a wider wake behind the fourth cylinder.