twin-screw, compressor, modelling, thermal distortion
A procedure is presented to estimate local clearance distortions in a twin screw compressor using boundary conditions derived from a chamber model. Time varying boundary conditions from the non-dimensional model are mapped onto rotor and casing surface arrays. The fluid boundary temperatures are time-averaged then used to estimate the local rotor and casing temperatures. Heat transfer assumptions that represent the extreme case for component temperature distributions are presented. The relative local change in clearances between rotors and casing are then investigated analytically. The effect of the revised clearances on the performance is quantified and compared against experimental results.