This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Efficient Modeling and Simulation of the Transverse Isotropic Stiffness and Damping Properties of Laminate Structures using the Finite Element Method
ISSN: 0148-7191, e-ISSN: 2688-3627
To be published on September 30, 2020 by SAE International in United States
Event: 11th International Styrian Noise, Vibration & Harshness Congress: The European Automotive Noise Conference
The Noise Vibration and Harshness (NVH) characteristics and requirements of vehicles are changing as the automotive manufacturers turn their focus from developing and producing cars propelled by internal combustion engines (ICE) to electrified vehicles. This new strategic orientation enables them to offer products that are more efficient and environmentally friendly. Although electric powertrains have many advantages compared to their established predecessors they also produce new challenges that make it more difficult to match the new requirements especially regarding NVH. Electric motors are one of the most important sources of vibrations in electric vehicles. In order to address the new challenges in developing powertrains that match the acoustic comfort requirements of the customers and also shape the development process as efficiently as possible, car manufacturers use numerical simulation methods to identify NVH problems as early in the design process as possible. Numerically describing the dynamic properties of electric motor components such as the stator or rotor is proving to be especially difficult as they contain heterogeneous parts that have viscoelastic orthotropic or transverse isotropic stiffness and damping properties. In this work, using a dynamic Representative Volume Element (RVE), the homogenized frequency dependent stiffness and damping properties of a laminated stator core are determined. Furthermore, two approaches for modeling the damping properties of these laminate structures are presented. The approaches refer to modeling damping using modal damping and complex stiffness matrices. The numerical results are compared to experimental data obtained by means of experimental modal analysis and the applied modeling approaches are validated. Finally, a model order reduction method is applied to the finite element model in order to further reduce its size. The classic Component Mode Synthesis (CMS) reduction method is enhanced with the possibility of modeling transverse isotropic damping properties. The new approach is validated in comparison with the full order finite element model.