Engine Oil Pans Optimization within a Vehicle Crash Scenario

Engine downsizing is a strong trend in automotive industry. Engines are getting lighter and smaller and are installed in bigger cars. As a consequence the integrity of the engine to vehicle crash, either for compliance to safety rules or different Euro NCAP's crash tests, is no longer guaranteed. It becomes necessary to maintain impact resistance while optimizing engine mass. PSA initiated a collaborative work with Altair, in order to test latest optimization developments.

Topological optimization is a powerful way to achieve minimum mass within geometrical constraints. The challenge here was to work with variable load and strongly non-linear behaviour. In our case the specifications were a set of time-dependant forces applied on the engine. These forces were extracted from a complete crash analysis. The aim was to avoid engine collapse during crash time. The ESLM method was first tested but convergence issues were detected. Then manual samplings of the loads were done and several selection patterns were tested: samplings of the time step and peaks load to take into account. Eventually, a new geometry that reaches the goal was identified, that allows a gain of 50% resistance with 10% of additional mass.

 

The Author

Bernard CHARLET
Engine Design Justification Specialist
PSA PEUGEOT CITROEN