基于VOF模型的导弹低速入水数值模拟方法

基于商用软件Fluent框架,利用动网格技术和UDF方法实现了回转体低速0°攻角直入水过程的数值模拟。采用水、气2相VOF方法捕捉界面,分别采用湍流与层流建立了导弹入水冲击的数值模拟方法,并与实验获得的照片进行了对比分析。分析结果表明:层流模型下导弹入水冲击的数值模拟和试验结果吻合较好,湍流模型下的数值模拟结果误差较大,因此,在低速条件下,湍流模型不适用,应该用层流模型。

Numerical Simulation Method of Water-entry Impact at Low Speed for A Missile Based on VOF Model

An underwater weapon will undergo stronger impact when it is in the incipient transient process of the entry-water, and this will cause serious harm to its structures and the carried instruments. It is very important to increase the reliability of the underwater weapon through researching the water entry impact of underwater weapon. In this paper, the numerical simulation of the vertical water-entry with zero attack angle at low speed for a missile is carried out based on the commercial software Fluent. The numerical simulation method of the water-entry at low speed for a column missile model is established using the technologies of dynamic mesh and UDF, and is validated by the experimental picture. The result shows that the numerical simulation accords with experimental results preferably at low speed for a missile with laminar flow model, however, the numerical simulation of the turbulence model shows an obvious error. So, the suitable method for low speed water-entry is not the turbulence model but the laminar flow model.