抄録
One method to predict the axial thrust is to use the relationship between the total head and axial thrust, where the axial thrust is supposed to be in proportion with the total head. But such method has insufficient prediction accuracy because it can not properly predict the circumferential velocity according to the direction of the leakage. We developed a numerical simulation method to predict the circumferential velocity properly. First, the numerical domain of the fluid part, including the impeller and vaned diffuser, was calculated. Second, that of the rear part located on the back side of the hub was calculated. The leakage in the rear part is usually about 5% less than the discharge in the fluid part, therefore the influence from the rear part to the fluid part is neglected. Three pump types were calculated and we could predict the maximum axial thrust with a high accuracy of ±6%.
