Positive and Reverse Design of Screw Rotor Profiles with Freeform Curve

In the traditional screw compressor rotors profile generation method, the process of cockamamie parameters adjustment and confirmatory will take a long time, so that the modified results can’t be estimated in advance. Based on freeform curve, two rotor profiles generation methods are presented in this paper. One method is positive, and the female and male rotor profiles are acquired by every profile segment defined with freeform curve; another one is reverse, and the rotor profiles are derived through the meshing line. The rotor profiles are fitted by freeform curve and the shape of rotor profile can be adjusted by moving the control points. Finally, the two methods are used to developed a system for designing quickly the rotor profiles.