淹没条件下水射流涡旋特性大涡模拟及实验研究

发布时间：2019-06-18 09:03

【摘要】：采用大涡模拟方法对淹没条件下水射流的涡量场进行数值模拟,分析流场中涡旋的产生与扩散机制,并通过相同条件下粒子图像测速仪测量射流的涡量场,对模拟结果和方法进行验证。模拟研究泵压和围压对淹没射流涡旋特性的影响。结果表明:在射流流场中,由喷嘴出口产生一系列涡量集中的点涡旋,随着射流的前进涡旋逐渐扩散,卷吸周围介质并传递能量,卷吸范围逐渐扩大,而卷吸能力沿射流轴向呈指数衰减;随着泵压升高,整个流场中涡旋的涡量值明显增大,涡旋扩散长度直线上升;围压对涡量基本没有影响,围压的增加会使涡旋扩散区长度直线下降,减小卷吸作用范围。
[Abstract]:The vortex field of water jet under submerged condition is simulated by large vortex simulation method, and the generation and diffusion mechanism of vortex in flow field are analyzed. The vortex field of jet is measured by particle image velocimeter under the same conditions, and the simulation results and methods are verified. The effects of pump pressure and confining pressure on the vortex characteristics of submerged jet are simulated and studied. The results show that in the jet flow field, a series of point vortexes with concentrated vortices are produced from the nozzle outlet. With the forward vortex of the jet diffusing, the entrainment range is gradually expanded, and the entrainment capacity decays exponential along the jet axial direction. With the increase of pump pressure, the vorticity value of the vortex in the whole flow field increases obviously, and the vortex diffusion length increases in a straight line. The confining pressure has little effect on the vorticity. The increase of the confining pressure will make the length of the vortex diffusion zone decrease in a straight line and reduce the range of entrainment.
【作者单位】：重庆大学煤矿灾害动力学与控制国家重点实验室;重庆大学复杂煤气层瓦斯抽采国家地方联合工程实验室;
【基金】：国家“973”计划项目(2014CB239206) 国家自然科学基金青年基金项目(51404045) 教育部长江学者和创新团队发展计划(IRT13043) 国家自然科学基金项目(51104191) 重庆市博士后科研人员特别资助项目(Xm2014036)
【分类号】：TD74

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