LAUSR

In this paper, a Euler-Lagrangian particle/fluid film/VOF coupled multiphase flow model is presented. Numerical simulations are conducted, and the rainwater accumulation and flow characteristics over two types of windshields are studied based on the presented model. The results show that an uneven water film is formed over the windshield, with rain water accumulation occurring for the concave windshield but not for the convex windshield. At low speeds, the average fluid-film thickness for a concave windshield is larger than that of a convex windshield; however, a minor difference occurs between these two values at high speeds, and a critical velocity is observed for the two types of windshields. When the train velocity is less than the critical velocity, the fluid film at the lower part of the windshield and the train nose flows downward, and beyond the critical velocity, the fluid film over the entire windshield and train nose flows upward. 本文建立了欧拉-拉格朗日粒子/流体膜/VOF 耦合多相流模型. 在此基础上, 通过数值模拟的方法研究了两种类型挡风玻璃的雨水聚集和流动特性. 结果表明, 挡风玻璃表面形成了一层不均匀的水膜, 凹面挡风玻璃表面存在雨水聚集现象, 凸面挡风玻璃表面没有雨水聚集现象. 当列车低速运行时, 凹形挡风玻璃的平均液膜厚度大于凸形挡风玻璃. 然而, 在列车高速行驶的情况下, 两者之间的差异较小. 此外, 存在使挡风玻璃流体膜流动方向发生改变的临界车速. 当列车速度小于临界车速时, 挡风玻璃下部流体膜和列车机头向下流动, 超过临界车速时, 整个挡风玻璃和列车机头上方流体膜向上流动.