Durability of Centrifugal Pump Impeller Blades Exposed to Corrosive–Erosive Wear

Abstract

The researchers have developed a theory of the corrosive–erosive wear applicable to the plates and shells of centrifugal or axial pump impellers; the theory takes into consideration the stress state and the stationary temperature field. Omitting the intermediate calculations, we present a system of differential equations in Marguerre-type partial derivatives on a normal deflection w and a stress function of the eighth order, which describe the stress state of a variable-thickness blade in the context of temperature effects. In this research, the blade thickness change function is set as cubic splines. Analytical solution of the equation system with the boundary conditions is based on using the Dorodnitsyn’s integral ratios method. Pursuant to the method, write the original equation system as a divergent system. Limited to binomial approximation and also choosing power polynomials and their derivatives as weights, apply the integral ratios method to the original system of equations to obtain a system of ordinary differential equations (8n order) with variable coefficients. The boundary value problem is solved by the modified method of successive approximations, developed by Prof. V. A. Pukhliy and published by him in the academic press.