Design And Flow Simulation Of Inducer For The Spray Pump

As the energy crisis getting more and more serious each day, the national energy policy has shaft its focus to nuclear power gradually. Safety is the most important issue in a nuclear power plant. Many devices have been designed to safeguard the plant and the spray pump is one of the key equipments for that purpose. In the operation process of the spray pump, a common phenomena is the cavitations on the impeller blade surfaces, as the result of very low pressure, that may produce much noise and cause vibration or even serious damage of the impeller. One of the primary methods to improve the cavitations performances of the pump is to fix an inducer before the inlet of the impeller to increase the pressure at the impeller inlet. Compared with other methods, inducer has these advantages such as simple configuration, easy manufacturing and installation, low cost, convenient servicing and replacing. However, not much research work has been done on the design of the inducer previously. The design of the inducer is arbitrary and must be testified by experiments.Based on the real three dimensional model of the inducer and commercial CFD software NUMECA, a flow analytical platform was developed in this thesis. Flow in the equal-pitch inducer was numerically analyzed and studied comprehensively to explore the work principle and the flow characteristics of the inducer. Problems in the inducer were discussed and variable-pitch design method were proposed and studied. Numerical results indicate that the variable-pitch design of the inducer can improve the cavitations performance of the spray pump greatly. The research results presented in this thesis may provide a useful reference in the practical design of the inducer for the spray pump and other kind of centrifugal pumps as well.