Numerical analysis and verification of pressure characteristics of elastomeric rotor pumps
LIAN Jiadi1,2,PAN Guojun3*,ZHU Zefei1
1. Department of Mechanical Engineering, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, China; 2. Department of Mechanical Engineering, China Jiliang University, Hangzhou, Zhejiang 310018, China; 3. Department of Information Engineering, Zhejiang Open University, Hangzhou, Zhejiang 310018, China
Abstract:To overcome the existing defect that elastomeric rotor profile with poor sealing and particle scratch of elastomeric rotor pumps, a novel scraping profile of the rotor was proposed. The proposed profile was composed of wide circular arc ab, scraping circular arc bc, equidistant curves of cycloid cd and circular arc de. CFX immersion solid method and RNG k-ε turbulent model were used to analyze the pressure characteristics of the rotor pump with different rotor envelope angles of θ=5°,8°,11°,15°,18°and different radius of r=30.9, 37.1,44.5,53.4 mm. The results show that the envelope angle and radius are the key parameters which directly affect the performance of the rotor pump. With the increase of the envelope angle, the instantaneous mass flow rate decreases, and the radius has no effect on the instantaneous mass flow rate at the outlet, the pressure fluctuation at the inlet and outlet, and the rotor chamber. With the increase of radius, the possibility of cavitation at the inlet meshing is reduced, and the pressure at the outlet meshing is reduced. The new rotor pump with θ=18°and radius r=53.4 mm was compared with the traditional rotor pump, the results show that the performance of the new rotor is better than the traditional rotor. The theoretical flow of the new rotor pump is 3.35% smaller than that of the traditional rotor pump, and the volume efficiency of the new rotor pump is 1%-5% larger than that of the traditional rotor pump. The efficiency of the new rotor pump is 1.5%-4.9% higher than that of the traditional rotor pump.