A design method of a variable-pitch internal meshing screw rotor and a twin-screw compressor rotor

Abstract

A design method for a variable-pitch internal meshing screw rotor and a twin-screw compressor rotor. The design method includes the following steps: firstly, selecting the pitches at multiple fixed rotation angles of the rotor as independent variables; The selected pitch is optimized, the optimal pitch at the fixed corner is obtained, and the coordinate points of multiple corners and the corresponding optimal pitch are determined; finally, a cubic spline curve is used to connect the coordinate points determined in step 2 to form a complete rotor helix . The compressor rotor includes an outer rotor and an inner rotor. The profile of the outer rotor is an outer equidistant line structure of short-amplitude hypocycloid; the inner rotor is one less tooth than the outer rotor, and the pitch circle center of the inner rotor is the same as that of the outer rotor pitch circle. Eccentric arrangement, the profile of the inner rotor and the profile of the outer rotor conform to the meshing relationship. The rotor of the invention has the advantages of less wearing parts, compact structure, high pumping rate, no surge, low vibration noise and the like.

Description

technical field [0001] The invention belongs to the field of compressors, and relates to a design method for a variable-pitch internal meshing screw rotor and a twin-screw compressor rotor. Background technique [0002] The twin-screw compressor is a positive displacement rotary compressor, which is used to obtain medium and low pressure gas, and has a wide range of applications in modern industry. It inherits many advantages such as long service life of rotary machinery, reliable operation, low vibration, low noise, stable operation and no surge phenomenon. Core components in systems such as supply, refrigeration, waste heat recovery, etc. At present, in order to facilitate processing, the commonly used twin-screw compressor rotor meshing relationship is external meshing, which leads to a large center distance between the rotors and a long leakage line length, thereby reducing the space utilization rate and increasing the leakage strength. Ultimately, the current screw ro...

AI Technical Summary

Problems solved by technology

However, in the helical design of the rotor, if the pitch of the rotor changes too much, the pressure difference between adjacent working chambers will be too large, thereby increasing the leakage intensity. If the pitch change is too small, it will lead to a longer leakage line length and increase the leakage. area

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