SUMMARY

The compression process within screw compressors induces large pressure and temperature changes that cause the rotors to deform. To determine this effect, a 3-D numerical method has been developed to calculate flow and deformation simultaneously. This comprises a mathematical procedure to generate a numerical grid for both the solid and fluid domains, in the form of a computer program named SCORG, attached to a commercial CCM software package. The effects of rotor distortion on the compressor performance were thus determined and are presented. NOTATION r- density p- pressure T- temperature m- mass V- cell volume t- time T- stress tensor S- viscous part of the stress tensor v- velocity u- deformation m, mt – molecular and turbulent viscosity k- thermal conductivity h- enthalpy ci- concentration of species k- turbulent kinetic energy P- production of turbulence energy e- dissipation of turbulent kinetic energy C, s- constants in k-e model of turbulence Gf- diffusion coefficient qfS, qfV – source terms in transport equation