FSAE赛车弯道气动特性数值模拟与试验研究

Experimental and numerical investigation on aerodynamics characteristics for Formula SAE at corners

为研究FSAE赛车处于弯道工况下的气动特性,建立一简化FSAE模型,使用重叠网格方法对直道和弯道工况分别进行数值仿真。并对八字绕环进行道路试验,与数值仿真进行验证。结果表明:赛车在弯道工况中气动力发生较大变化,气动阻力增加1.5%,气动下压力增加6.5%,赛车在弯道中产生额外气动力矩,导致赛车趋于转向不足。在弯道内外侧,车身压力分布不对称趋势,侧倾角的存在是扩散器与底板下压力增大的主要原因,前轮转角影响了前翼涡流的运动,减小了前翼下压力。在八字绕环试验中测得整车下压力为121.9 N,与整车模型数值仿真相比,误差约1.6%。

To investigate the aerodynamic characteristics of FSAE cars under corner conditions,a simplified FSAE model is established and the overset mesh method is used to simulate the straight and corner conditions.The Skid Pad road experiment is conducted and verified with numerical simulation.The results show that the aerodynamic force varies significantly in corner conditions,in which the aerodynamic drag increases by 1.5%and the aerodynamic downforce increases by 6.5%compared to a straight condition.The additional aerodynamic moments generated in corners will cause the racing car to understeer.The surface pressure distribution of the body inside and outside the corner is asymmetrical.The existence of roll angle is the main reason for the increase of the lower pressure of the diffuser and underbody.The steering angle of front wheel affects the movement of front wing vortex and result in a loss of downforce of front wing.In Skid Pad experiment,the downforce of real racing car stands at 121.9 N,the error approximately 1.6%compared with the simulation.