New cycloid rotor profiles design under different rolling circle radii for Roots vacuum pumps

Abstract

Article highlights 1. Two new rotor profiles are proposed and designed to improve the performance for Roots vacuum pump. 2. For the new rotor profile formed by a large rolling circle, its volume utilization rate is greater than 60%, which can pump more gas in a cycle and significantly better than that of traditional profile, such as arc profile. 3. For the new rotor profile formed by a small rolling circle, its pressure ratio is greater than traditional rotor profiles because its length of minimum gap between rotor profile and chamber is critical increased to decrease the back flow.

Keywords

• Roots vacuum pump
• Cycloid
• Conjugate
• Rotor
• Profile
• Rolling circle