The effects of wavy surface on flow structure after a bluff body

Abstract

This study is about the effect of wave-like structure on flow against a bluff body. PIV technique has been used to measure the flow velocity and capture flow pattern. Variable surface condition and position of the bluff body were tested under specific flow. Two-dimensional numerical solution for the same test conditions have performed. Turbulent model of ε − k were employed. Sinusoidal surfaces were chosen for wavy condition to represent the wavy boundary. Comparisons were made against flow over the flat surface for the same condition. The result shows, increase the amplitude of the wavy boundaries has inversely relationship to the vortex size and strength for the same position of the bluff body. The result also shows as the bluff body moves horizontally toward close to the valley the vortex become smaller in size and strength. Flow over flat surface displays, in general less number of vortices. In general experimental and numerical solutions were in good agreement in predicting the flow pattern. However, slight qualitative differences were observed.