Influence of multi-parameter optimization design on hydraulic performance of water-jet propulsion assembly
ZHANG Yan1,2, WANG Luyi1, ZHONG Jinqing3, LONG Yun3*
1. Science and Technology on Water Jet Propulsion Laboratory, Marine Design & Research Institute of China, Shanghai 200011, China; 2. School of Naval Architecture, Ocean and Civil Engineering, Shanghai Jiaotong University, Shanghai 200240, China; 3. Natio-nal Research Center of Pumps, Jiangsu University, Zhenjiang, Jiangsu 212013, China
Abstract：Water-jet propulsion pump was optimized by adjusting the shaft strut blade number, the shaft strut blade outlet angle, the distance between the shaft strut and the impeller, and the tip clea-rance. The flow field of a certain type of water-jet propulsion assembly was simulated by CFD, and the influence of different geometric structure parameters on the performance of water-jet propulsion pump was analyzed. The results show that with the increase of the number of blades, the curves of head, efficiency and power gradually are in a downward trend. When the blade number of the shaft strut and the blades is equal to that of impeller, the head and power curve will suddenly drop. When the blade outlet angle of the shaft strut is within the range of(-25°, 25°), the head curve and the efficiency curve show a linear upward trend with the outlet angle of the blade increase. With the increase of the outer diameter length of the suction tube, the entrance area variation decreases, the curve of the head and efficiency gradually decreases, then tends to be flat, and finally increases, and the change of the power shows a downward trend. With the increase of the distance between the shaft strut and the impeller, the head curve gradually rises and then tends to be flat, the power change law is consistent with the head change law, and the efficiency curve first increases and then decreases. With the increase of tip clearance, the work efficiency of the impeller decreases, and the head, efficiency and power curves all show a downward trend. The research results can improve the hydrodynamic performance of the water-jet propulsion assembly, which has great application value to promote the develo-pment of the water-jet propulsion technology, and provides a certain basis for the optimization design of the water-jet propulsion assembly.
