Microscopic shrinkage is easy to generate in the aluminum alloy impeller as a result of uneven thickness and complicated design structure.Combining with the actual production conditions

filling and solidification process of initial design for aluminum alloy impeller were simulated.Through analyzing flow morphology

the solidification sequence and shrinkage porosities

and comparing with actual produced impeller

origination of defects in the original process was presented.Based on the above mentioned results

using InteCAST software

casting process optimization for aluminum alloy impeller was conducted

and a optimized design was presented.The actual impeller was produced to verify the availability of the simulated results.The results show that the optimized design can reduce effectively the shrinkage porosity（choles）in the castings.