A series of aero-thermo-mechanical analyses were carried out to predict the running tip
clearance and the effects of impeller deformation on the performance using two different
centrifugal compressors (blade type A and B). In operation, impeller deformation due to the
combination of centrifugal force, aerodynamic pressure and thermal load results in nonuniform
tip clearance profile. The results show that the maximum displacement occurs at
the leading edge tip of the impeller blade but maximum stress takes place at the blade root
of the impeller. A significant reduction of the tip clearance height has occurred at the leading
edge and the trailing edge of the impeller. Due to the reduction of the tip clearance, the tip
leakage flow has decreased by 19.4% and 16.2% in the blade type A and B, respectively. The
polytropic efficiency of blade type A and B at operating condition has increased by 0.72%
and 1.81%, respectively.