基于相群平衡模型的舰船气泡尾流数值模拟

为了获得舰船气泡尾流中的气泡尺度分布规律，首先采用欧拉双流体模型（Euler Two Fluid Model）中的单一气泡模型对集装箱船模型KCS（KRISO Container Ship）进行了数值模拟.然后将气泡分组，进行基于相群平衡模型（Population Balance Model）的数值模拟.获得的气泡数密度和体积分率等气泡分布特征后，通过对索特平均直径的分析，探讨了初始平均气泡直径的选取和气泡尺寸分组等因素对气泡尾流的影响.结果表明：大气泡将聚集在船体表面；自由面则以小气泡为主.ETF模拟可以作为PBM计算的初值.当初始化的均一气泡直径取值越接近索特平均直径，PBM计算越容易收敛.

Numerical Simulation of Ship Bubbly Wake Based on Population Balance Model

Firstly, the bubbly wake around a model-scaled KRISO container ship KCS was numerically simulated based on the Euler two-fluid(ETF) model with uniform bubble size. Then the bubbles were divided into a few size groups, and the ship bubbly wake was numerically simulated again based on a discrete population balance model(PBM). The size distribution characteristics of bubbles such as number density and volume fraction of each size were derived. The effects of initial uniform bubble size and the size groups on the wake were researched through the analysis of mean Sauter diameters. The results show that the big bubbles aggregate on the ship wall, while small bubbles on the free surface; the ETF results can be used as the initial value of PBM; the more close the uniform ETF bubble size to the mean Sauter diameter, the more easy the PBM computation converges.