The visualization of filling!of air-conditioner housing for automobile was conducted by the JSCAST software on the basis of establishing a 3D model combining with practical technology.The simulated results

which are well in agreement with practical production

show that the shrinkage（porosity）would occur in the junction of inlet and housing where the change of thickness is sharp

and the absence of air gas entrapment could be observed due to smoothly filling.The defects at the above mentioned locauion can be effectively eliminated by setting gate at the junction to strengthen feeding effect and by shortening the length of core to optimize the structure of housing

and so on.The results show that the computer visualization can optimize the scheme to improve the quality of the housing.