Establishment of CFD method for the hydrodynamic design of high-speed cavitating water jet nozzle

本工作旨在为高速水下射流数值模拟和喷嘴水动力设计建立一种实用的CFD方法。主要研究结果如下：(1)建立了一种基于气泡空化简化估计的可压缩混合流方法。(2)考虑气泡膨胀和收缩的影响，对空化流的涡动粘度进行了修正。(3)对浸没孔喷管发出的湍流激活射流进行了数值模拟，实验验证了该方法的可靠性。(4)研制了一种新型的套孔喷管，并通过可视化实验对其性能进行了评价。

This work has been performed on purpose to establish a practical CFD method for the numerical simulation of high-speed submerged water jets as well as the hydrodynamic design of jet nozzles. The main results can be summarized as follows: (1) A compressible mixture flow method based a simplified estimation of bubble cavitation is established. (2) A modification on the eddy viscosity of cavitating flow is proposed considering the effect of bubble expanding and contracting. (3) Numerical simulation of turbulent activating jets issuing form submerged orifice nozzle were carried out and the reliability of present method has been verified experimentally. (4) A new sheathed orifice nozzle is developed and its property has been evaluated via visualization experiment.