基于Fluent角型喷嘴内部空化行为的数值模拟

利用Fluent流体计算软件对角型喷嘴内部的空化流场进行了数值模拟,得到了喷嘴内部的压力、气相生成速率和汽含率分布场,并对三种扩张角喷嘴内的流场进行了比较分析.结果表明:在角型喷嘴内部,空化汽泡主要在喷嘴圆柱段壁面起始点和扩张段壁面起始点两处产生;在扩张段壁面起始点处,由于回流和压力两种因素的共同作用导致扩张角对空化汽泡生成速率的影响存在最优值;随着扩张角的减小,角型喷嘴在扩张段壁面的空化区域不断扩大,其汽含率也不断攀升;扩张角的改变对角型喷嘴圆柱段区域的空化行为没有明显影响.

Fluent-Based Numerical Simulation of the Cavitation Behavior in the Angle Nozzle

Using the Fluent software to simulate the field of cavitation flow in the angle nozzles， the distribution of pressure， mass transferring rate from liquid to vapor and vapor fraction were obtained. The flow fields in the three nozzles with different divergence angles were analyzed by comparison. The results showed that in the angle nozzles， the cavitation bubbles were mainly generated at the starting point of the cylindrical region’s wall and divergence region’s wall. Under the working of reflux and pressure， an optimal divergence angle which impacts the generating rate of cavitation bubbles at the starting point of divergence region’s wall exists. With the divergence angle decreasing， the area of cavitation on the wall of divergence regions expands continuously， and the vapor fraction also increases gradually. Changing divergence angles has no obvious effect on the cavitation behavior of cylindrical regions.