Effects of chord length of hydrofoil and azimuth angle on startup performance of vertical-axis hydrokinetic rotor
1. School of Energy and Power Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China; 2. Shandong Industrial Pump and Motor Co., Ltd., Zibo, Shandong 255095, China; 3. 704th Research Institute of CSSC, Shanghai 200031, China
Abstract: To solve the problems of small startup moment and long startup time of the Htype hydrokinetic rotor, the simulation and analysis were conducted by the computational fluid dynamics method. The six degree of freedom (6DOF) method was adopted to model the variation of rotational speed of rotor with the torques acting on rotor. Comparison and correlation analysis were conducted among transient flows, rotational speed and output torque at different initial setting angles. The results show that there is no explicit correlation between rotational speed and output torque during the startup process of the vertical shaft hydrodynamic rotor with straight blade. As the rotor starts up at the minimum static torque, the time required to reach the maximum rotational speed and output torque is longer than that associated with the maximum static torque. As the maximum rotational speed is attained, low-pressure zones are produced in the area enclosed by the blades, which is insensitive to the initial setting angle. Large area of lowpressure zones is responsible for low output torque. As the rotor starts up at the maximum static torque, the integrity of the wake flow is relatively high. The rotational speed experiences increasing, decreasing and subsequent regular oscillation, which is common at different chord lengths of the airfoil. As the chord length is increased from 0.16 m to 0.24 m, the startup time is extended by 0.63 s, and the average rotational speed is decreased for the stabilized rotation, but the fluctuation amplitudes remain nearly invariant.
康灿, 汪志远, 叶卫明, 丁可金. 翼型弦长和方位角对垂直轴水动力转轮启动性能的影响[J]. 江苏大学学报(自然科学版), 2022, 43(5): 554-561.
KANG Can, WANG Zhiyuan, YE Weiming, DING Kejin. Effects of chord length of hydrofoil and azimuth angle on startup performance of vertical-axis hydrokinetic rotor[J]. Journal of Jiangsu University(Natural Science Eidtion)
, 2022, 43(5): 554-561.
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