Full Vehicle Virtual Acoustic Prototyping using Test-Based Models and Blocked Force Descriptions 2023-01-1085

Vehicle Acoustic Prototyping in the mid to high frequency range is challenging with numerical models only. To overcome this challenge, over the past decade, experimental techniques were developed that allow the engineer to incorporate Test-Based models in the simulation as well. Using Virtual Point Technology these Test-Based models serve well to describe, for example, the complex dynamics of the vehicle body / NTF. Here the high modal density and damping characteristics are simply measured on a mule or prototype vehicle and coupled using Dynamic Substructuring to cover the mid and high frequency ranges as well. As such accurate predictions and / or risk assessments can be made much earlier in the vehicle development stage. While test-based models serve well to describe the coupled vehicle dynamics, loads to compute actual vehicle responses are needed as well. Here so-called Equivalent or Blocked Forces are ideal as they are found to be independent of the vehicle dynamics. This means they will remain the same while entering virtual Dynamic Substructuring optimisations of the vehicle components with respect to their effect on the noise at the driver’s ears. This paper introduces the technical concepts mentioned with an example case on an Electric Vehicle.