iChrome’s software solutions, Nexus and Shaper, have been instrumental to Same Deutz-Fahr, a leading tractor manufacturer, to achieve weight reductions and an overall performance increase of complex 3D assemblies such as Front Axle Supports. The main objective of this work was to improve the initial shape of a tractor front axle support with the goal to minimize the overall weight under performance requirement constraints. An overall weight saving of 15% compared to the previously adopted design, has been globally achieved.
Methodology:
Figure 1: Flange details: initial and optimised solution
Using Shaper the parametrization can be defined directly on the FEM model and the new configuration can be immediately obtained by the means of morphing the original mesh. The optimization process can then be integrated with any external FEM solver using Nexus and the whole procedure can be completely automated. This leads to a great deal of time saving and to drastically reduce design costs.
During this project, the thickness and overall dimensions of a front axle support have been optimized in order to reduce the total mass of the component. Constraints on the structural performances have been taken into account during the design process.
The design space has been partitioned over different sections to correctly define the morphing parameters. The structural optimization has been solved using Nexus starting from an initial Design of Experiments (DoE) based on Optimality criterion. The structural performances have been evaluated using the Nastran direct Integration node available in Nexus.
Advantages in using Nexus:
Figure 2: Optimised stress contour
Main advantages of using Nexus are:
- easy integration of external FEM and CFD solvers i.e. Nastran, Abaqus, Radioss, Fluent, Ansys and Adams
- accurate 3D morphing using advanced nonlinear techniques that preserve the original quality of the mesh
- parallel and concurrent evaluations to fully utilise your hardware and software resources
- access to all your results via organised tables and SQL external databases
- advanced Design of Experiment (DoE) and statistical tools to explore and analyse results
- state-of-the-art libraries for single optimization leading to the optimal solution
Results:
An overall weight saving of 15% compared to the previously adopted design, has been globally achieved. The optimized solution maintains stress and global displacement levels under the allowed limits by reducing the size of the lateral flanges and reinforcements significantly. Where a lower stress level has been detected, and by efficient re-shaping of the higher stress level regions.
(*) Published on A&C. Cervasio,F.Galli, M.Mariani – Analisi e Calcolo. “Optimization of Tractor front Axle Support by means of advanced 3D Mesh Morphing” – Analisi e Calcolo – December 2014
