流动参数对混输泵全流道内气液相间作用特性的影响

Numerical Analysis for the Influence of Flow Parameters on Phase Interaction in a Multiphase Rotodynamic Pump

为了解流动参数对混输泵内气液相间作用特性的影响,针对不同进口含气率(3%、9%、15%)、不同流量(0.75Qd、Qd、1.25Qd)和不同进口气泡直径(0.1 mm、0.4 mm、0.7 mm、1.0 mm)条件,利用ANSYS CFX对一叶片式气液混输泵进行了全流道数值模拟。计算结果表明:不同进口含气率下,泵内气液相间作用力中均是阻力起主导作用,湍流弥散力大小可忽略;随进口含气率增加,各相间作用力逐渐增大,且叶轮内相间作用力的增大幅度大于导叶。当Q=0.75Qd时,叶轮进口处阻力、附加质量力、升力以及叶轮内阻力均出现了明显增大。同时,进口气泡直径增加,叶轮内阻力、附加质量力和升力均增大,而导叶内相间作用力的变化相对较小。

To understand the influence of flow parameters on the phase interaction in the multiphase rotodynamic pump,simulations with ANSYS CFX were performed under different IGVFs(3%,9%,15%)as well as different flow rates(0.75 Qd,Qd,1.25 Qd)and different bubble diameters at impeller inlet(0.1 mm,0.4 mm,0.7 mm,1.0 mm).The numerical results show that the drag is the most important and the magnitude of turbulent dispersion force can be neglected.The interphase forces increase gradually with the increase of IGVFs.Furthermore,the increase of interphase forces in impeller is greater than that in guide vane.Under condition of Q=0.75 Qd,the drag,added mass force and lift at impeller inlet,as well as the drag at the middle of impeller,increase significantly.Meanwhile,the change trend of interphase forces is obvious than that in guide vane if the bubble diameter increases at impeller inlet.