【作者】 冉鲁光； 陈云良； 赵阳； 徐永； 王波；

【Author】 RAN Lu-guang;CHEN Yun-liang;ZHAO Yang;XU Yong;WANG Bo;State Key Laboratory of Hydraulics and Mountain River Engineering, College of Water Resource & Hydropower, Sichuan University;

【机构】 四川大学水力学与山区河流开发保护国家重点实验室水利水电学院；

【摘要】 为探明射流特性对射流泵流场的影响,采用紊流模型对有平直段喷嘴和无平直段喷嘴进行了三维数值模拟。对比分析了两种喷嘴时射流泵的性能、流速分布、压强特性等。研究表明:有平直段喷嘴时出口速度分布均匀,且射流中心附近流速高于无平直段喷嘴时,有利于提升被吸液速度;喉管进口附近射流边界层区的轴向速度相对较大,卷吸液体的效果优于后者;后者在工作液与被吸液混合后,射流流核有一段明显的加速过程,增加了能量损失;在同一流量比下,前者的压力比及效率略高于后者。无平直段时喷嘴出口附近的压强高于有平直段时,随后出现较为明显的压强降低。射流特性及喉管内流场的计算成果,对研究射流泵喷嘴结构有参考价值。更多还原

【Abstract】 To find out the influence of jet characteristics on flow field of jet pump, 3-D numerical simulation was conducted on jet pumps with straight-section nozzle and non-straight-section nozzle by applying the turbulent model. The differences between two kind of nozzles in performance, velocity distribution and pressure characteristics of jet pumps were researched. The results show that the exit velocity of straight-section nozzle is evenly distributed and the velocity near jet center is higher than non-straight-section nozzle, which is better to promote the velocity of entrained liquid. The axial velocity of jet boundary layer near the throat pipe inlet is relatively higher, so it entrains liquid more efficient than the latter. As the jet flow core of the latter is accelerated obviously after primary flow and entrained flow mixing, the energy loss increases. The pressure ratio and efficiency of the former are slightly better in the same flow rate ratio. The pressure near the non-straight-section nozzle exit is higher, then a quite obvious pressure drop occurs. The calculation of jet characteristics and flow field in the throat pipe can provide a reference for the study of jet pump nozzle structure.更多还原