Dynamic characteristics of the 48-inch water tunnel drive pump

In this report, the dynamic characteristics of the 48-inch water tunnel drive pump are determined using the theory of unsteady flow around a two-dimensional cascade of airfoils developed by Ohashi (1). This analysis assumes that the axial surge velocity is uniform across the face of the impellar. It is found that the magnitude plot of the dynamic characteristics is similar to that of a simple control lag element whereas the phase plot looks quite different. The solidity of the rotor in the present analysis need not be large as assumed in previous investigations.