通气超空泡洞壁影响及其比尺效应数值模拟

摘要

Based on RANS equations,the wall effect and scale effect of ventilated supercavity has been simulated using inhomogeneous model and SST turbulence model with consideration of gas-water interaction and gravity effect.The influence of different turbulence models to gas ventilation coefficient has been investigated.The developing process of ventilated supercavity under different ventilation rates is shown through numerical simulation,and the cavity shape and resistance differences at different scale and in unbounded flow field are compared.The results show that the cavity length and diameter of the small-scale model are greater than that of the large-scale model.But the extent of the upper cavity drift of the small-scale model is less than that of the large-scale model.The length,diameter and the extent of the upper cavity drift at the unbounded flow field are greater than that of in the wall effect condition.In the drag-reducing,the maximum drag reduction of the small-scale model is greater than that of the large-scale model.The maximum drag reduction of the unbounded flow field is smaller than that of in the wall effect condition.%基于RANS方程,采用分相流模型和SST湍流模型,考虑了水-气两相之间的相互作用及重力效应,对通气超空泡的洞壁影响及其比尺效应进行了研究.研究了不同湍流模型对通气率的影响,通过数值模拟复现了通气超空泡在不同通气率条件下的发展过程,比较了水洞中不同模型比例和无界流场中在空泡形态和阻力上的差别.研究结果表明,小比例模型在空泡的长度和直径上都要大于大比例模型,但空泡的上漂程度要小于大比例模型,无界流场条件下的空泡的长度、直径和上漂程度都要大于有洞壁影响条件;在减阻效果方面,小比例模型的最大减阻比例偏大,无界流场