The influence of secondary flows in the thrust acting on the axis of a radial lox pump

Abstract

The authors investigate the influence of secondary flows in the thrust acting on the axis of a liquid oxygen radial pump with operating conditions like those of a Vinci upper-stage rocket engine. For a high circumferential Reynolds number, pressure and velocity distributions are obtained by varying geometrical parameters known to influencing the flow in the cavities between the impeller and the housing. The results obtained with the numerical method are compared with those calculated with formulae relying on the rotation factor k. The Finite-Volume Method is applied to three-dimensional impeller-housing models. The results indicate the axial thrust estimated using the formulae returns overestimated values as compared with those computed with the numerical method, such fact suggesting that corrections might be needed when one considers applying the design guidelines to radial pumps driving liquid oxygen.