Study on the Internal Flow Characteristics of High Flowrate Emergency Drainage Series-parallel Pump

Abstract Floods have become the main natural disaster threatening the safety of peoples lives and property. It is of great significance to develop high flow emergency drainage equipment. An innovative structure of pumps with high flow rate and multiple operating conditions is proposed in this paper to achieve series and parallel operation. It established an automatic optimization platform that integrates functions such as 3D modeling, mesh generation, computational fluid dynamics, and scheme optimization, and developed an efficient hydraulic model for a volute mixed flow pump combining flow field diagnostic techniques. The research results indicate that the inlet distortion of the secondary stage pump is the main cause of pump performance loss for both series and parallel operation condition. The third-generation vortex identification method was used to diagnose the internal flow of the pump under two operating conditions and control strategies were proposed. The final optimization scheme show that the pump can reach 1800 m 3 /h with a head of 9.6m and efficiency of 80% in parallel operation condition. In series operation condition, the pump can reach 900 m 3 /h with a head of 18.3m and an efficiency of 75.3%.