Study on the Quimby-tooth rotor profile for dry screw vacuum pumps

This paper summarizes three Quimby-tooth rotor profile (QRP) generation models for dry screw vacuum pumps. Seven typical profiles are generated and compared to reveal their differences in curve structure, meshing line, parameter design range, and geometrical characteristics. The analysis indicates that there still is insufficient design flexibility for the typical profiles in the application of conical rotors. Therefore, a novel rotor profile is further proposed, in this paper, by modifying an existing profile. The advantage of the novel profile is identified through a specific design case. Results show that the summarized profile generation models provide an effective means to generate typical profiles and create novel profiles. In comparison with traditional profiles, the proposed profile achieves a 2.8% reduction of the contact line length and a 1% boost of the internal compression degree for conical rotors. This paper presents effective references for profile design and optimization of dry screw vacuum pumps. Graphic Abstract [Formula: see text]