Lightweight Acoustic System Performance Target Setting Process 2013-01-1982
In the vehicle development process, one important step is to set a component performance target from the vehicle level performance. Conventional barrier-decoupler dash mats and floor trim underlayment systems typically provide sound transmission loss (STL) with minimal absorption. Thus the performance of such components can be relatively easily specified as either STL or Insertion Loss.
Lightweight dissipative or multi-layered acoustic materials provide both STL and significant absorption. The net performance is a combination of two parameters instead of one. The target for such components needs to account for this combined effect, however different suppliers use unique formulations and manufacturing methods, so it is difficult and time consuming to judge one formulation against another.
In this paper, a unique process is presented to set a component target as a combined effect of STL and absorption. This process utilizes a Statistical Energy Analysis (SEA) vehicle level model to create a spreadsheet based Response Surface Model in MS Excel. The combined effect of the acoustic components can then be evaluated against a vehicle level target in spreadsheet without the need to input each supplier's submission into the vehicle level SEA model. This method greatly simplifies the specification process as well as allowing suppliers to quickly evaluate the impact of their parts on the vehicle level performance without the knowledge of the performance of any other vehicle content.