Analysis and numerical simulation of claw vacuum pumps with novel three-claw rotors. (October 2021) - Pan, Shiyang
Abstract: The rotor profiles of the claw vacuum pump mainly determine its working performance. The composition curves of the existing three-claw rotor profiles are complicated, and the compressed gas remaining in the carryover is recompressed, resulting in a remarkable increase of power consumption. For solving those problems, a sinusoidal curve was used to smoothly connect the addendum and dedendum arcs, and a novel three-claw claw rotor and its parametric equations were obtained. A novel discharge port was designed to avoid the secondary-compression of the gas in the carryover. The working process and the internal flow field of the new three-claw vacuum pump (TCVP) were revealed through numerical simulations. The mass flow rate at the proposed discharge port was also analyzed. Study results show that the proposed claw rotor has considerable advantages of simple profile, high internal volume ratio and small relative carryover. The designed discharge port realizes complete gas discharge without secondary-compression of the gas in the carryover. It is revealed that part of gas in the chamber formed by the separation of the compression chambers can flow back to the suction chamber in the compression process. Highlights: Novel three-claw claw rotors for claw vacuum pump were proposed. A novel discharge port for the new three-claw vacuum pump was designed. Effects of geometrical parameters on the proposed vacuum pump were analyzed. The working process and internal gas flows of the proposed pump were simulated.