Numerical simulation research about riblet surface with different spacing

The numerical simulation about riblet surfaces with different spacing was carried out at different velocities. Some rules about riblet surface's drag reduction effect influenced by spacing were found out primarily. According to the characteristic of riblet surface's flow field, computation region, grids and flow parameters were dealt with reasonably. Results are as follows. Riblet surface with spacing has better drag reduction effect than that without spacing. Drag reduction effect reaches the best while the spacing size is equal to riblet structure. The reason that drag reduction effect of riblet surface could be influenced by spacing is that the spacing can restrain the increase of pressure drag.