Thrust Prediction in Screw-Type Centrifugal Pump

A screw-type centrifugal pump is a kind of non-clog type pump and has been widely used, for instance, for drainage of rainwater as well as slurries and mud in sewage control systems (Reference to Fig. 1). In order to avoid choking the impeller passage with the congestion of solids, the impeller is designed to have a wide passage whose configuration is screw formed by a three-dimensional spiral blade added to a conical hub cone. The prediction of radial and axial thrust is important and useful information for the safe operation and the impeller design, to say nothing of the internal flow prediction and pump performance prediction. Particularly, the fluctuation of radial and axial thrust in this pump is large because of one blade. Therefore, to predict the thrust correctly is important. In this paper, the radial and axial thrust has been numerically predicted. Especially, the numerical result on the radial thrust is compared with the experimental results. The validity of thrust prediction has been discussed.