Influence of Flow Field's Radial Dimension on Ventilated Supercavitating Flow

通气超空化流域径向尺度影响

School of Marine Science and Technology, Northwestern Polytechnical University, Xi'an 710072, China

Received: 9 September 2019

Abstract

To investigate the influence of flow field's radial dimension on the flow of the portion gas-leakage supercavity, based on the two-fluid multiphase flow model and SST turbulence model, considering the compressibility of ventilated gas, a 3D simulation model of ventilated supercavity was established to simulate the flow of the supercavitation, which was consistent with water tunnel experiment. The effect of flow field's radial dimension on ventilated supercavity's dimension and pressure distribution was studied. The results show that flow field's radial dimension has a significant effect on the ventilated supercavity's dimension and pressure distribution. When flow field's radial dimension ratio is 6.5 times lower than the maximum diameter of supercavity, the supercavity cannot be formed to completely enclose the underwater vehicle. With the increase of flow field's radial dimension, the pressure inside and outside the supercavity decreases, and there is a pronounced increase in supercavity dimension. When flow field's radial dimension ratio is 54.0 times greater than the maximum diameter of supercavity, the dimension and pressure distribution of ventilated supercavity remain unchanged, which coincides with the theoretical results. In addition, the calculation results provide a criterion for simulating the shape of ventilated supercavity in the open environment, which can be used to guide engineering practice.

摘要

为研究流域尺度对阵泄气通气超空化的影响，基于分相流模型和SST湍流模型，考虑通气可压缩性，建立了通气超空泡流动的三维数值模型，通过水洞实验对数值方法进行了验证，研究了流域径向尺度对通气超空泡尺度和压力分布特性的影响。计算结果表明：流域径向尺度对通气超空泡流型及压力分布影响显著。流域径向尺度比小于6.5时，无法形成完全包裹航行器的超空泡，随着流域径向尺度增加，超空泡尺寸增大，空泡内压力和外流场压力均减小；当径向尺度比大于54.0时，空泡尺寸和内部压力达到稳定收敛，计算结果与经验公式吻合，研究结果为模拟阵泄气通气超空泡自由流场空泡形态提供了流域径向尺度的选择标准，可用于指导工程实践。