Multi-objective Optimization Design of Sliding Bearing of High-speed Centrifugal Pump Based on Lubrication Characteristics Analysis

Wear aggravation under high temperature is the main failure mechanism of sliding bearing of high-speed fuel centrifugal pump. In order to improve the service life of bearings, a multi-objective optimization design method for sliding bearing based on the distribution law of lubrication characteristic is proposed from the perspective of heat control. Firstly, based on the Reynold equation and energy equation of oil film hydrodynamic lubrication flow, the thermal fluid lubrication model of centrifugal pump sliding bearing combining Reynold equation and adiabatic flow energy integral equation is constructed, considering the change of medium viscosity with temperature and pressure. Secondly, the lubrication characteristics of sliding bearing under different clearance ratio, eccentricity ratio and width-diameter ratio conditions are analyzed respectively. Finally, aiming at reducing heat generation and increasing heat dissipation, the multi-objective optimization design method for sliding bearing structure based on improved particle swarm algorithm is adopted to reduce the temperature rise and wear of bearing. The research results show that the heat generation of the optimized bearing is reduced by 33.28%, the friction factor is reduced by 28.69%, the minimum oil film thickness is increased by 23.28%, and the average temperature rise is reduced by 17.9%. Under the condition that the oil film bearing capacity can still meet the radial force load demand of centrifugal pump, the lubrication performance of bearing is effectively improved.