液力偶合器气液两相流动的数值模拟与粒子图像测速

为了更加真实地反映偶合器内部的气液两相流动机理，该文应用计算流体力学（computational fluid dynamics，CFD）对其内部流动的速度和压力等流场特征进行数值模拟,并应用粒子图像测速（particle image velocimetry，PIV）技术对其流场进行了测试，试验结果表明：泵轮内的气泡小而均匀，速度分布较规律，由内环向外环递增；涡轮内气泡较多，并出现了涡流、回流、二次流等不规则流动现象。PIV测试的流场流动趋势与数值模拟的流场流动趋势基本一致。CFD数值模拟方法和PIV技术为揭示液力偶合器内部流场的复杂流动提供有效的解决途径。

Numerical simulation and particle image velocimetry for gas-liquid two-phase flow in hydraulic couplings

In order to more truly react the mechanism of gas-liquid two-phase flow in fluid couplings, the method of CFD(computational fluid dynamics) simulation was used to numerically simulate flow field characteristics in fluid couplings, such as internal flow velocity, pressure and so on, and the technology of PIV(particle image velocimetry) was adopted to test flow field in fluid couplings. The results showed that bubbles in the pump wheel were small and uniform, velocity distribution of pump was regular and increased from inner loop to outer loop; the bubbles in the turbine were more obvious, the turbine came out irregular flow phenomena of vortex, reflux, secondary flow and so on. Flow trend of PIV test and numerical simulation were nearly same. The numerical simulation method of CFD and PIV technology provides effective method to reveal complex flow of the internal flow field characteristics in the hydraulic coupling.