The flow characteristic around two circular cylinders in side-by-  side arrangement near a plane wall was investigated experimentally and numerically. The lower cylinder was embedded in a turbulent boundary layer whose thickness is about fifty percent from the cylinder diameter. The Reynolds number based on the diameter of single cylinder was 53000. The pressure distributions along the surface of the cylinder and the plane wall were measured for the gap-to-diameter of cylinder ratio  and the center to center spacing between the two cylinders was constantly maintained at  where G was the gap between lower cylinder surface and plane wall, while T was transversal distance among two circular cylinders. A flow pattern between cylinders was visualized with the 2D-URANS numerical simulation with k-w SST as a turbulence viscous model. In fact, an evolution of pressure distributions in circular cylinders, especially at the lower cylinder, is influenced by a plane wall which is located near them. The gap flow is biased to one side, resulting in the formation of narrow wake behind one cylinder and a wide wake behind the other.

circular cylinders, side-by-side arrangement, plane wall.