Finite Element Simulation of Thermoplastic Polyurethane Components for NVH Transfer Path Analysis

Abstract

Thermoplastic polyurethane (TPU) has emerged as a versatile material for noise, vibration, and harshness (NVH) control due to its tuneable viscoelastic properties and compatibility with additive manufacturing. This study presents a finite element-based modeling framework for the characterization and evaluation of TPU in transfer path analysis (TPA). Nonlinear stiffness and damping functions were implemented based on literature data, while frequency-dependent viscoelastic behavior was introduced through storage and loss modulus functions. Contact interactions were modeled with nonlinear springs incorporating frictional effects to capture realistic interface dynamics. Vibro-acoustic coupling was investigated using a FEM-based approach, and further assessed using hybrid FEM–BEM methods. The results showed close agreement between predicted mode shapes and analytical expectations. Displacement fields were reproduced with high fidelity, and higher-order modes highlighted the importance of including frequency-dependent damping and friction models. Hybrid FEM–BEM coupling improved acoustic predictions while reducing computational cost. Parametric optimization further demonstrated that small modifications in TPU thickness and support positioning can reduce sound pressure levels by up to 15%. Overall, the simulations suggest that TPU has significant potential for application as both a structural  decoupler and acoustic absorber in NVH engineering, providing a numerical framework that can guide lightweight and multifunctional designs in automotive and related engineering fields.