Effect of a Triangular Rib on a Flat Plate Boundary Layer

The flow structure downstream of a triangular rib over a thin plate placed in a wind tunnel was experimentally investigated using a boundary layer hotwire anemometer. Flow and boundary layer characteristics, such as thickness, shape, and turbulence parameters, were studied at different freestream velocities and streamwise locations corresponding to ReX of 1.7 × 104–2.8 × 105 for plates without and with a leading edge rib. It was found that the boundary layer of the flow over a ribbed wall was 3–3.5 times thicker and had higher turbulence intensity and smaller turbulence length scales compared to its smooth wall counterpart.