数值波流水池构造方法研究

Research on the method of constructing a numerical wave-current flume

该文在FLUENT软件平台下构造了二维数值波流水池。基于不可压缩流体RANS方程建立数学模型,使用VOF方法追踪自由面位置;将水池入口取为波浪与水流相遇并产生相互作用的起始位置,给定入射静水波和水流叠加的边界条件;在水池下游设置消波区,采用动量源项消波方法对波浪进行衰减,消除波浪在水池出口边界处的反射,生成了波浪和水流共存的稳定流场。针对不同水流流速剖面和波浪条件进行了数值模拟,并通过实验数据考核数值水池模型的准确性。对Thomas的实验数据进行数值仿真,得到了不同流速的均匀逆流对波高和波长的影响;针对剪切流,模拟了Kemp等的实验数据,计算不同波幅的波浪在非均匀顺流和逆流中的变形。结果显示,数值结果与实验数据吻合良好,表明了该数值波流水池模型能够较为准确地模拟波浪和定常水流的相互作用。

A numerical wave-current flume is developed using the CFD software FLUENT. The numerical model is based on the RANS equations and VOF method. The flume inlet is defined as the position where the interactions between the currents and the waves set in. An artificial damping zone is located before the outlet boundary to remove the reflected waves. The validityof the numerical wave-current flume model is examined by previous experimental works. We start with the simplest uniform current condition. The interactions between the uniform currents and the linear waves could be described as the Doppler shift effect. The experiments conducted by Thomas are simulated to analyze the wave length and amplitude variations with the currents. For shear current condition, the experiments conducted by Kemp and Simons is studied numerically. The numerical results show good agreement with the measured data, which indicates the numerical wave-current flume can accurately simulate the interaction between waves and steady currents.