风洞移动带系统对气动升力影响的数值模拟

摘要

To study the effect of moving belt on the results of aerodynamic lift force measurement in wind tunnel experiments, computational fluid dynamics technique is used to conduct the numerical simulation on moving belt system. The results show that once the belt is moving it always produces lift force, which increases with the rise of incoming flow velocity, even in unloading conditions and no matter whether there exists incoming flow or not. But when the simple car model is put on the moving belt, the lift force decreases. The additional lift force the moving belt produces brings about an error of more than 25% in measuring lift force of tested vehicle. Therefore, to obtain the correct value of aerodynamic lift force in wind tunnel experiments, the lift force of moving belt must be deducted.%为探讨风洞移动带系统对气动升力测量的影响,采用计算流体动力学方法对移动带系统进行数值模拟.结果表明,当移动带自身空转时,无论是否有来流,都会产生升力,且该升力随着来流速度增大而增大.当移动带上方有简化汽车模型时,其自身产生的升力会有所减小.移动带产生的附加升力导致实验车升力测量误差高达25％以上.因此,在风洞实验中必须扣除移动带产生的升力,才能得到正确的气动升力值.