绕圆盘空化器空化流动及阻力特性的数值分析
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绕圆盘空化器空化流动
及阻力特性的数值分析
余志毅，时素果，王国玉
（北京理工大学机械与车辆工程学院，北京 100081）
摘 要: 应用基于滤波器的湍流模型（FBM）对绕圆盘空化器空化非定常流动和阻力特
性进行了数值计算和分析。计算中，雷诺数保持不变，通过改变来流压强获得不同的空
化数，分别为 0.3，0.7 和 1.0；FBM 模型通过二次开发嵌入至商业软件 CFX 中；模型的
可靠性应用水洞试验结果进行验证。结果表明，随着空化数的减小，绕圆盘空化器的空
化区域由与空化器分离转变为附着于空化器，空化区的变化由逆压梯度引起的反向射流
造成。大空化数时，尾迹中更明显的旋涡分布将增强空化器所受阻力的周期性和波动性；
随着空化数减小，当空化区附着于空化器后壁时，圆盘空化器所受阻力变得稳定。
关键词: 圆盘空化器；空化流动；阻力特性；滤波器模型
中图分类号: TV131.32 文献标识码：A
Numerical Analysis of Mechanism and Drag Characteristics
of the Cavitation Flow around a Disc Cavitator
YU Zhi-yi, SHI Su-guo, WANG Guo-yu
(School of Mechanical and Vehicular Engineering,
Beijing Institute of Technology, Beijing 100081)
Abstract: The unsteady cavitation flow around a disc cavitator and its drag characteristics were
numerically studied using the filter-based model (FBM). The simulation was carried out in a
constant Reynolds number but different cavitation numbers (0.3, 0.7, 1.0), which were attained
through the pressure variation of the inlet flow. The FBM model was embedded into the
commercial software CFX through secondary development and validated with the water tunnel
experiments. The numerical results show that the cavitation region will turn attached with the
cavitator with the decrease of the cavitation number and this variation is caused by the reentrant
jet arised from the adverse pressure gradient. The wake vortex can increase the periodicity and
fluctuation of the drag force acting on the cavitator in the condiction of large cavitation number,
and with the decrease of the cavitation number, a stable drag characteristic curve will be acquired.
Key words: disc cavitator; cavitation flow; drag characteristics; FBM
钝体绕流现象广泛存在于城市建筑、桥梁、流体机械、核反应堆和海底管道等众多领域，
由于伴随着流动的分离、再附以及尾迹区的非定常涡脱落等复杂特征而引起人们的重视。对
基金项目：国家自然科学基金资助项目（50679001），高等学校博士学科点专项科研基金（20070007047）
作者简介：余志毅（1976-），男，讲师，E-mail:yuzhiyi@bit.edu.cn
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