Design Optimization and Robust Design for Fatigue

Jeff Mentley (HBM nCode), Sumeet Parashar (ESTECO)

HBM nCode is a powerful tool used for fatigue and durability analysis, and this presentation illustrates some integration cases with modeFRONTIER, for multi-objective optimization design.
The first case is relative to the Robust Design, or Design under Uncertainties, of an aluminium carter. The structural model is defined in Ansys Workbench, and the stress results are elaborated by HBM nCode to compute the Design Life; both software are easily integrated in modeFRONTIER workflow. 

The purpose of the analysis is to verify if, for a given uncertainty distribution of some design parameters (as like as load scale factor, material properties and surface roughness), the confidence bound of Design Life is higher than a required safety minimum. The second application is relative to the Multi-Objective Design Optimization of a Connecting Rod. Also in this case, Ansys Workbench is used for the structural analysis of the component in two working conditions (firing and return), and is integrated within modeFRONTIER with HBM nCode to compute the Design Life. Through modeFRONTIER, the geometric design parameters of the component are optimized following different and contrasting criteria: minimizing mass, minimizing maximum stress, and maximizing Fatigue Life, with given design constraints.