Influence of blade angles on performance of micro axial flow hydraulic turbine
YANG Sunsheng1*, ZHAO Erce1, KONG Xiangxu2
1. National Research Center of Pump, Jiangsu University, Zhengjiang, Jiangsu 212013, China; 2. China Construction Machinery Co., Ltd., Beijing 100070, China
Abstract：In order to investigate the influence of blade setting angle on the hydraulic performance of micro axial flow hydraulic turbine, a micro axial flow hydraulic turbine with a specific speed of 548 was chosen as the research object. Without changing other geometric parameters, seven runners with diffe-rent blade setting angles were obtained by offsetting the runner blade. Based on experimental verification, the influence of blade setting angle on the hydraulic performance of micro axial flow hydraulic turbine was analyzed using the computational fluid dynamics technology. The results show that when the blade angle decreases, the head and output of the turbine increase under the same flow rate while the high-efficiency area shifts to the small flow area, and the range of efficient operation of the hydraulic turbine increases to a certain extent. With the increase of the blade setting angle, the head and output of the hydraulic turbine decrease, and the high-efficiency area shifts to the large flow area. The hydraulic turbine with an appropriately reduced blade angle can maintain better performance over a wide range of head(flow rate)variations. The highest efficiency of the hydraulic turbine with a placement angle of -4° reaches 82.13%, with the largest range of high-efficiency regions. This study can provide some reference for the design of micro axial flow hydraulic turbine runners.
