The consequences of incorrect assembly of the water pump impeller can be serious. Therefore, when installing and maintaining a water pump, great attention must be paid to the assembly of the impeller to ensure that the water pump can operate normally and perform as it should.

Through the implementation of correct measures, the cause of the impeller falling of the water pump can be effectively determined and corresponding avoidance methods can be taken to ensure the safe and stable operation of the water pump.

the impeller design of the drainage pump not only affects the liquid transmission and pressurization capacity of the pump, but is also directly related to the performance, efficiency, stability and service life of the pump. Therefore, when designing and selecting a drainage pump, the design of the impeller is a key factor that must be carefully considered.

This paper aims to explore the method of determining the geometric dimensions of the centrifugal pump impeller. By analyzing the working principle and design parameters of the centrifugal pump, combined with experimental data and theoretical calculations, a method for determining the geometric dimensions of the impeller based on similarity conversion method and performance optimization is proposed.