Influence of insertion of holes in the middle of obstacles on the flow around a surface-mounted cube

The aim of this study is to analyze the impact of insertion holes in the middle of obstacles on the flow around a surface-mounted cube. Four configurations of obstacles in a channel with a Reynolds number, based on obstacle height, ReH = 40000 are studied. The hexahedral structured meshes are used to solve the fluid dynamics equations. The finite volume method is employed to solve the governing equations using the ANSYS CFX code and the turbulence model k-ω SST. The streamwise velocity profiles, time-averaged streamlines, turbulence kinetic energy, and drag coefficient are presented. The results show the appearance of a second vortex behind obstacles with the hole from diameter D/H=0.2. The turbulence kinetic energy is greater on top of the obstacle. It is more intense for the obstacle with no hole, as this intensity decreases with the increase in the hole diameter. The drag coefficient is improved only for the case D/H=0.32.