Nenya A. Features of the working process of an intermediate stage of a radial-flow pump

In order to improve the parameters of operation quality of an intermediate stage of an radial-flow pump, features of the flow structure in the clearance between the impeller and the guiding device was researched as well as the criterion analysis of the guiding devices was made. The purpose was to enable optimization of their design by the quality of the generated flow structure at the inlet under the conditions of block-module designing. The mathematical model of the flow is based on the laws of conservation and movement for an incompressible fluid, k - ? turbulence model. The mathematical model allows to calculate a field of hydrodynamic parameters of flow in the flow passage of the pump. The obtained results of studying the flow structure have shown significant non-uniformity of distribution of the absolute speed and the flow angle at the impeller outlet as well as dominating influence of non-uniform distribution of the circumferential component of velocity. The flow structure is determined by the shape of the meridian cross-section and the angle of blade installation at the impeller outlet. The performed criterion analysis of the guiding device has allowed to specify dimensionless criteria for estimation its operation quality. The performance characteristics of intermediate stages with a guiding device of traditional and improved design of the entrance section are obtained experimentally. Basing on the obtained results, the method of the calculation of the guiding vanes taking into account the interaction with the impeller at the stage of designing of new modifications is added and extended.