A micro centrifugal compressor was designed for centimeter-scale micro turbomachinery

which has a diameter of 26 mm

designed rotate speed of 240 000 r/min

and designed mass flow rate of 30 g/s.Three-dimensional numerical simulations under adiabatic and isothermal conditions of solid wall were performed by using the commercial CFD(computational fluid dynamics) software CFX.The results show that

as compared with adiabatic condition

the mass flow rate at the isothermal condition decreases 7.53%

total to total isentropic efficiency decreases about 18.1%

total pressure rate decreases 21.7% at the same shaft work input.Taking the effect of heat transfer into account

the micro centrifugal-flow compressor was redesigned.CFX simulation results show that the improved design satisfies the design requirement of the micro turbomachinery.