SEA in Vehicle Development Part I: Balancing of Path Contribution for Multiple Operating Conditions

The application of Statistical Energy Analysis (SEA) to vehicle development is discussed, with a new technique to implement noise path analysis within a SEA model to enable efficient solution and optimization of acoustic trim. A whole vehicle Performance-Based SEA model is used, in which Sound Transmission Loss (STL) and acoustic absorption coefficient characterize subsystem performance. In such a model, the net contribution from each body panel/path, such as the floor, to a specific interior subsystem, such as the driver's head space, is extremely important for vehicle interior noise development. First, it helps to identify the critical path to root-cause potential problems. Second, it is necessary in order to perform balancing of path contributions. With current software, the power based noise contribution analysis is for direct paths/adjacent subsystems. Noise path balancing requires the net contribution from each body panel for a given load case or excitation (tire/road noise or powertrain noise). A method to calculate and balance the net panel noise contributions under several operating conditions is discussed.