某两栖车绕流场数值模拟研究及外形优化分析

Numerical Study of Flow Field around an Amphibious Vehicle and Its Improvement in Shape

运用多块混合网格,采用RNG湍流模型、流体体积法(VOF)和PISO算法对某型两栖侦察车带自由表面的粘性绕流场进行了数值模拟研究,数值方法采用相关试验数据进行了验证,误差在9%以内。针对模拟结果显示的影响其水动力特性的主要结构部位和外形参数进行了优化,并计算分析了轮穴、车体切角、车轮状态以及车首导流板对两栖车航行性能的影响。计算结果表明,改进后的车体绕流场特性得到了较大的改善,航速10km/h时减阻效果可达原车总阻力的69.2%,有效地提高了某型两栖侦察车的航行性能。

Numerical simulation of an amphibious vehicle＇s ambient flow field which accounts free surface effort is made by using RNG-turbulence model, volume of fluid （VOF） model and Pressure Implicit with Splitting of Operators （PISO） method based on multiblock hybrid meshes. The computed total resistance less than 9% difference from corresponding experimental data, the agreement is good. Then primary research has been done on optimizing the geometrical characteristics of the amphibious vehicle which influence the hydrodynamic characteristics, including the cavity of the wheel, cut angle in the bodywork, the state of the wheel and the leading board in foreside. The computational results show that the hydrodynamic characteristics of the vehicle which has been improved is better than that of the original, which diminishes the total resistance 69.2% at the speed of 10km/h.