Let Simulation do the Design - Faster

This presentation was made at the 2019 NAFEMS World Congress in Quebec Canada

Resource Abstract

In times of new 3D printing technology progresses every day, topology optimization has already been identified as an ideal tool to create new design ideas. Additional design constraints can be added in order to take specific process and form conditions into account. Therefore, CAE engineers are dreaming of a design by simulation.



But the result of a topology optimization cannot be directly sent to the printer in many cases, because a number of important conditions are not yet part of the topology optimization. First of all, the surface is not smooth and smoothing changes the structural behaviour. Moreover, intermediate densities are an obstacle against automated interpretation. The classical approach is to forward the smoothed surface to the designer, who then should be inspired by the topology optimization result to find a new and better design. This new design has to be meshed and computed again to hopefully show the intended improvements. Sometimes, several loops between CAE engineer and designer are necessary until a satisfactory design could be achieved. This is the time aspect.



Other aspects are related to points, which are not directly considered during topology optimization, like safety factors and endurance, uncertain material, shape and loading parameters. Such factors make the design workflow more complex and the question is, can we save time and gain quality by using more automatic steps to postpone or even replace the job of the designer?



One possible way to fulfil these required conditions is to use shape optimization as a second step after topology optimization. By this way, final shaping can be performed to fulfil the additional conditions on durability, uncertainties, and other conditions.



The model of an engine bracket is used to show the complete design process. In particular, challenges and their solutions during this process will be highlighted. All computations are carried out using one industrial FE software (PERMAS).