Effects of Riblet Shape of Non-smooth Surface on Aerodynamic Characteristics of Vehicle

摘要

To reduce the aerodynamic drag of the vehicle, three kinds of riblet shape non-smooth surfaces were arranged in the tail of the Motor Industry Research Association (MIRA) stepped-back vehicle mode. The shapes of the non-smooth riblet elements are triangular, circular and rectangular. Computational fluid dynamics (CFD) method was used for numerical analysis. To verify the effectiveness of the analysis method, the analysis result of the standard MIRA stepped-back vehicle mode was compared with wind tunnel test data. The tail-flow, pressure and turbulent kinetic energy of the MIRA stepped back vehicle modes, which were arranged with riblet elements, were analyzed. The effects of riblet shape of non-smooth surfaces on the reduction of vehicle' aerodynamic drag were compared with each other. The simulation results show that the three kinds of non-smooth surfaces have a good effect on drag reduction by reducing the negative pressure in the tail zone of the model, reduce the turbulent kinetic energy and reduce energy dissipation. The circular non-smooth surface is better than the other, with drag reduction effect of 5.53%.