水流冲击管道内滞留气团现象的VOF模型仿真分析

针对复杂管道系统内水流冲击滞留气团现象,采用VOF模型(Volume of Fluid Model)进行了数值模拟计算,并与一维模型进行了比较计算分析,结果表明:系统的最大压力并不总是气团的最大压力,有可能还会叠加水体对管壁的撞击而形成的突然升高压力.与实验实测结果的比较分析表明:采用VOF模型,能够较精细地仿真水流冲击滞留气团现象的气团形态、流场结构以及压力分布等的变化过程,其压力数值计算结果与实验实测基本吻合,其计算误差明显小于现有一维模型的计算误差,是深入研究该复杂瞬变流现象的有效方法.

Simulation and analysis of the rapid filling in pipeline containing trapped air mass with VOF models

The VOF (Volume of Fluid) models were applied in this paper to simulate the rapid filling process in complex pipeline system containing trapped air mass, and the comparison was made with that of one-dimensional mathematical models. According to the results, the maximum pressure of the system is not always equal to the maximum air pressure numerically, and it could be overlapped by the sudden increased pressure caused by the water striking on pipe wall. From the comparison between the results of VOF models and experimental tests, we can know that, the shape change of air mass, the configuration of flow field and the pressure distribution at any time can be accurately simulated with the VOF models, and the calculation results are basically consistent with the experimental results. Moreover, the calculation error of VOF models is obviously smaller than that of the existing one-dimensional models, and the VOF models are an effective method to study the phenomenon of the complex transient flow.