35°Ahmed模型气动射流减阻主动控制

Active flow control of 35°Ahmed model to reduce aerodynamic drag with steady jet

使用CFD仿真软件STAR-CCM+,对类车体35°Ahmed模型的尾流场进行仿真,采用主动控制减阻技术,用定常射流的方法研究射流孔的位置、速度等因素对尾部流场的影响。在尾部各个可能减阻的位置布置射流孔,针对不同的射流速度进行分析,并对不同位置采用逐步优化减阻的方法,找到最好的减阻工况。研究结果表明:与原始工况相比,采用射流减阻方案的模型尾流结构得到了明显改善;控制了模型尾部的分离涡;改变了车体的压力变化;降低了模型的压差阻力,使其阻力系数明显降低;实现了超过6%的减阻效果,达到了减阻的目的。

The wake flow of Ahmed model with 35°slant surface is a typical flow in the low aerodynamic drag regime,which is simulated using CFD code STAR-CCM +.The active control technique for drag reduction with steady jet is adopted to study the effects of position and velocity of the jet on the tail flow field.The jet holes are arranged at different positions around the tail.The best drag reduction conditions are gradually obtained by analyzing different jet velocities and different jet locations.Results show that the wake flow structure of the model with jet is obviously improved,and the separation vortex of the model is controlled compared original condition.Pressure difference and coefficient of drag are obviously reduced.More than 6% drag reduction is achieved.The active control is a good measure to reduce the aerodynamic drag of the Ahmed model in low drag regime.