FLUENT-based Wear Research for the Centrifugal Sewage Pump

Abstract

Adopting SIMPLE algorithm, k-e-Ap turbulence model and tetrahedron non-structure grid simulates the flow field of sewerage pump in the Descartes reference frame. Through numerical simulation, flow characteristics and distribution rule of sold particles in sewerage pump are obtained, which supply can contribute to optimization design of centrifugal sewage pump. Introduction The centrifugal sewage pump is a kind of centrifugal pump which has little blades. It is suitable for the transmission of fluid medium contains solid particles below 80°C. With good Non-clogging performance and simple manufacture, it has been widely used. Based on the internal flow of sewage pump is a complex three-dimensional flow, the flow discipline is not completely clear and the design theory is not perfect, so it is necessary to research on the internal flow of sewage pump. In the solid-liquid two-phase flow, the common methods are Euler and Lagrange. In Euler method, solid particles are regarded as pseudo-fluid, and particles and fluid are considered as continuous medium with co-existence and mutual penetration. The flow of pseudo-fluid is described with conservation equation in the macroscopic continuum principle, while the flow interaction of solid-liquid two-phase is mainly indicated by solid viscosity and solid pressure. In Lagrange method, the liquid and solid particles are regarded as continuous medium and discrete system respectively. Investigate the motion of liquid in Euler coordinate, and research the motion of solid particles in Lagrange coordinate which means the particle trajectory model. Its interaction is mainly processed through the perfectly elastic collision model or particles discrete element method. In this paper, the solid-liquid two-phase turbulent flow of centrifugal impeller for sewerage pump is simulated through FLUENT software, which adopts N-S equation, k-e-Ap turbulence model and SIMPLE algorithm. Through numerical simulation, flow characteristics and distribution rule of sold particles in sewerage pump are obtained, which can supply reference to optimization design of centrifugal sewage pump. The basic theory of turbulence model calculation model In this paper, the two-phase flow of centrifugal pump when transport the water and solid particles is simulated based on the following assumptions: 1. The flow is steady, three-dimensional, and isothermal with incompressible. 2. The shape of the solid particles remains unchanged during the motion. 3. There are no mass and energy exchange between the solid-liquid two-phase and two-phase. Based on the above assumptions, The Euler model is used to analysis the centrifugal sewage pump with sparse two-phase medium. Equations: the basic equations are as follows. The continuity equation in Euler model is given by Eq. 0 ) ( = ⋅ ∇ p p p v  ρ α (1)