Upfront truck NVH refinement through virtual simulation approach

Abstract

Nowadays in the commercial vehicle segment, noise and vibration is getting more important as customers are demanding better comfort without compromising on fuel economy and payload capacity. This paper focuses on developing the methodology for predicting in-cab noise and tactile vibration on steering wheel and driver seat rail for operational WOT load case. The vibro-acoustic simulation was performed using FEM-FEM method with fully coupled approach. The process was divided in three sections: first, prediction of input excitations forces by MBD model, secondly applying these forces to FE model to predict noise and vibrations, thirdly weak point analysis, optimisations and iterations for the peaks which are not meeting targets. Weak point analysis includes transfer path analysis (TPA), panel contribution analysis (PCA) and operational deflection shape (ODS) to understand the weak points of the structure. Weak points are identified using virtual TPA to show the correlation with weakness of frame lateral stiffness. The countermeasures worked out upfront in virtual validation stage to improve the weak points and design changes are implemented in the final design. The overall process helped to meet first time right with 40 kg weight saving. Further the established process was followed for rest of the truck projects.