THE EFFECT OF BLADE PROFILE ON THE PERFORMANCE OF A SIDE CHANNEL PUMP

Abstract

This article presents the results of a numerical modeling of a steady turbulent flow of an incompressible fluid in an open-type vortex pump with an open side channel, comparing the generalized simulation results with the existing experimental data. The mathematical model is based on the Reynolds-averaged Navier — Stokes and continuity equations, as well as on the equations of the two-layer Realizable k-ε turbulence model that accounts for the curvature of streamlines. The authors have estimated the grid independence of the solution and studied the influence of 14 blade profiles on the head and efficiency of the vortex pump. The solution of the model equations was achieved by the finite volume method using a sequential algorithm in three calculation areas (“feeder channel”, “blade wheel”, “open hull side channel and diverter channel”) with the evaluation of grid independence of the solution. The result of the solution between the calculated areas was transmitted at the corresponding points of the interface surfaces. The authors have studied the influence of 14 profiles of a blade on pressure and efficiency of the vortex pump: the initial profile of the blade with the installation in the wheel coaxial shaft of the ring plate of different width, the initial profile of the blade with a bevel on the discharge side, a profile in the form of an isosceles triangle, a profile in the form of a quadrangle, the initial profile with a rounded blade on the suction side, and a profile in the form of a rectangular triangle with a rounded blade on the suction side, among others. The simulation results have aided in proposing the blade profiles: in the form of a rectangle with a convex rounding of the blade on the suction side with a 10 mm radius and a right-angled triangle with a concave rounding of the blade on the suction side with a 52 mm radius and without rounding, giving a significant increase in pressure — more than 20%. Nevertheless, none of the considered cases have revealed any significant increase in the vortex pump hydraulic efficiency.