OPTIMIZATION OF STRUCTURAL
COMPONENTS AND SHORTENED DESIGN CYCLE
About the Customer
For more than 60 years, L&L Products have been providing unique solutions to the
automotive industry. They offer a custom engineering service in the domains of static sealing, acoustics, vibration reduction, structural reinforcements, and composite components for automotive, aerospace, commercial vehicle, and other industrial applications.
A growing part their product offering is “Composite Body Solutions” (CBS™) which has great applications in the automotive industry to help reduce structural weight and noise, while maintaining or improving both local and global structural stiffness, durability, and crash worthiness.
L&L Products CBS™ structural reinforcement technology comprises of a foaming structural adhesive on a highly-engineered thermoset or thermoplastic carrier. Commonly used to enhance overall body-in-white (BIW) stiffness, other benefits include load path management, section integrity, light-weighting, increased durability, while having no impact in body shop practices. CBS™ goal is to deliver an efficient solution for both current and future applications needing lightweight, strong structural parts, like electric vehicles (EV) battery protection.
Their traditional workflow was a three-step process that involves extracting the surfaces from the initial CAE model to build an offset envelope of the surfaces and then creating a high-fidelity
tetra mesh of the candidate design space. It relies on both CAE and Design/CAD resources,
takes up to an hour, and often needs to be repeated multiple times depending on how many
CBS™ inserts are intended for a vehicle.
Their goals were clear: to reduce CAE model build time with a CAE-driven process in which the
models were built exclusively by the CAE engineer, thus shortening their time to market by removing the reliance on other teams.
L&L Products also needed to attain optimization results faster to enable different variants to be explored to achieve a truly optimal solution. All of which accelerates the overall CBS™ development process.
Altair® HyperWorks® offers a best-in-class environment that includes, but is not solely focused on topology optimization to identify the best material position to give an optimized mass/performance. The model build and setup allows users to run and analyze models using the Altair® OptiStruct® topology optimization solvers. By using voxel elements, the process is streamlined into an single-step workflow delivering significant time savings. Of equal importance, there is no loss of accuracy in the results and computational expense is not negatively affected.
The traditional workflow took about 1 hour per area and the expertise of CAD and CAE
engineers to accomplish the three-steps (CAE model extraction, build offset envelope in CAD,
tetramesh CAD) before running the model. Whereas, the new approach took 5 minutes per area
and effectively replaced the old three-steps with a single, local voxel mesh step without need
for CAD user involvement. Comparing results between the old and new workflows for a
CBS™ part, the BIW torsion mode is effectively the same; +3.0 Hz (old) and +3.1 Hz (new).
L&L Products was able to reduce the model build setup times by 80%. Altair’s new approach also integrated into L&L Products existing processes while maintaining accuracy.
Fig 1: Adhesive expansion during BIW ecoat oven
Fig 2: CBS™ part - environment
before and after structural adhesive