Study on Flow Field Characteristics of Double Two-Hinge Three-Pitched Disc Turbine Rotating Impellers
The flow field in a stirred tank equipped with the double two-hinge three-pitched disc turbine rotating impellers was simulated by computational fluid dynamics(CFD).The effects of the rotational speed of the impellers(N),installation height of impellers C1 and impeller pitch C2 on the flow field in the stirred tanks were analyzed,and the simulation results were validated by PIV experiments.The result shows that when the rotating speed N=100rpm,the low-velocity area near the inner wall almost disappears,the overall velocity of the fluid in the tank is improved and the velocity distribution of the flow field is optimal.The increase of distances from the bottom will cause the high-velocity area of the flow field in the stirred tank moves up.When the distances from the bottom C1=0.28h,improvement of the fluid velocity in the area near the liquid surface is significant,and the velocity distribution of the flow field in the stirred tank is reasonable.The increase of the impeller spacing can alter the interaction of the upper and lower impellers.The mixing effect in the tank is the best when the impeller spacing C2=0.25h,the flow rate of fluid increased significantly in the area near the liquid surface,and the overall velocity of fluid in the stirred tank is fast.The research results can provide reference for the practical engineering application of double two-hinge three-pitched disc turbine rotating impellers.
double two-hinge three-pitched disc turbine rotating impellerCFD numerical simulationPIVflow field