Reliability-based Casting Process Design Optimization

Optimum casting designs are unreliable without consideration of the statistical and physical uncertainties in the casting process. In the present research, casting simulation is integrated with a general purpose reliability-based design optimization (RBDO) software tool previously developed at the University of Iowa. The RBDO methodology considers uncertainties in both the input variables as well as in the model itself. The output consists not only of a reliable optimum design but also of the knowledge of the confidence level in this design. An example is presented where the design of a riser is optimized while considering uncertainties in the fill level, riser diameter, and the riser pipe depth prediction. It is shown that the present reliability-based method provides a much different optimum design than a traditional deterministic approach.