Lightweighting of a trailer chassis

Automotive graduation assignment

Patrick Naar

I graduated at Femto Engineering on a lightweighting study of an optimized trailer chassis concept design with help of simulation driven design principles. Simulation results where directly used to shape the design in the conceptual phase, making simulation an integral part of in the design process. In this post I’d like to share with you the results of my work and the tools & methods used to obtain these results.

Develop lighter, develop better

For this assignment I worked with a long time client of Femto Engineering, specialized in the production of containers and trailers. The aim of the research was to present the client with a concept design of a trailer chassis able to transport a 20ft tanker, but with significant less weight compared to a baseline chassis.

Solution used

Simcenter 3D with the linear NX Nastran solver from Siemens PLM Software was used for this lightweighting project. Simcenter 3D was a logical software choice since it brings CAD and CAE features together in one platform. This facilitates the iterative process tremendously, because it makes it very easy and intuitive for engineers to switch back and forth between modeling geometry and running analyzes.

Examining the baseline

The development of the concept trailer started with determining the relation between the torsional stiffness of the baseline trailer chassis and the torsional stiffness of the tank container. The video below shows the displacements in the baseline chassis after the torsion loadcase. Next I simulated the baseline chassis using six loadcases with the purpose of studying the stress development in the chassis during actual operating conditions in order to fully understand how the chassis is loaded. The study showed that during the operating conditions the chassis was mainly loaded on vertical deflection. Below video shows the stresses on the goose-neck of the baseline chassis during the static loadcase.

The results

After a thorough assessment of the simulation results, several criteria were stipulated on which I based four concept designs. Each concept represents a different design approach. After examining the results on overall performance, one concept was chosen that showed a reduction of 22% in mass compared to the baseline chassis. But more importantly, compared to the baseline chassis the chosen concept also showed an overall improvement in mechanical behavior. The design of the concept chassis is shown in the image below.

Personal note

At the automotive program at Rotterdam University of Applied Sciences I learned a lot about CAD, but at Femto Engineering I found a professional space to really develop to my CAE skills as well. A successful internship would have never been possible without the knowledge, expertise and enthusiasm of all my colleagues. I would like to thank Femto Engineering for giving me the chance to be part of a great team and for all the support during the internship.

lightweighting continues

Ron van Marel, Femto’s new automotive intern, will add to my lightweighting efforts a clearer view of the baseline trailer by performing more simulations of different (combinations of) load cases. Load cases like braking, cornering or taking a speedbump. Furthermore he will investigate the function of the mid-section of the trailer (between the longitudinal beams of the trailer). Also the kingpin area of the trailer will be investigated with the aim to reduce even more weight.

Every year, Femto Engineering offers students the chance to further extend their technical knowledge by offering challenging internships. Don’t hesitate to inform about the possibilities we can offer you!

lightweighting of a Trailer Chassis - Femto Engineering