Structure optimization of an annular jet pump using design of experiment method and CFD

Abstract

This paper adopts DOE (the design of experiment method) to find out the optimum structure combination of an annular jet pump for maximum efficiency. The annular jet pump (AJP) model used by previous researcher, which area ratio is 1.75, was chosen as the simulation prototype. The performance data from the experiment were used to validate the simulation results. Then four important factors namely the flow ratio, the relative throat length and the included angles of the diffuser and the suction chamber were selected for the structure optimization by DOE. The most desirable combination is obtained, namely suction angle of 15 degree, throat length of 2.45 times of throat diameter, diffuser angle of 4 degree. The flow ratio corresponding to the most desirable combination is 0.6. The maximum efficiency predicted by the design method is 36.3% close to that of the CFD results 35.8%. The flow ratio has prevailing influence on the AJP efficiency. In the three construction parameters, the relative throat length has greater influence on the AJP performance than the diffuser angle and the suction angle. With proper experimental design method, effort to experiment could be greatly saved and analysis of experiment results could be more logical.