Numerical analysis of the fluid-solid interaction in twin-screw positive displacement machines
by
Ahmed Kovacevic
City University London, Northampton Sq, EC1V 0HB, London, United Kingdom
Coauthors: Nikola Stosic, Ian K. Smith

Efforts are continually being made to produce screw compressors with smaller clearances in order to reduce internal leakage. However, since the compression process induces large pressure differences across the rotors and temperature rise, they deform. A reliable method of estimating the interaction between fluid flow parameters and rotor deflection is thus needed in order to minimise clearances while avoiding contact between the rotors and the casing. A 3-D mathematical procedure is presented here to generate a numerical grid comprising both solid and fluid domains. This can be used to calculate the fluid flow and compressor structural deformation simultaneously by means of a suitable commercial numerical solver. Simulation results demonstrate the effects of change in working clearances, caused by rotor deformation, on compressor performance. Results of the analysis of combined compressor-expander machines are also presented in the paper.

Date received: February 13, 2004

Copyright © 2004 by the author(s). The author(s) of this document and the organizers of the conference have granted their consent to include this abstract in Atlas Conferences Inc. Document # cakt-52.