Search Results

Powertrain NVH and Powertrain Sound Quality requirements are among the key attributes to meet when developing new engines or vehicles. Source-Path-Contribution (SPC) solutions are commonly used to support the vehicle design and development. They allow to quantify the relative contributions of the different excitation sources, whether airborne or structure-borne, and the transfer paths to the noise and vibration measured at the receiver locations. When performed in time domain, SPC analysis is also a very effective tool to evaluate interactively the powertrain Sound Quality and how it can be affected by design changes. In this paper, we present a joint project performed by B&K Global Engineering Services together with Subaru where the team leveraged SPC models for powertrain noise of existing vehicles to create a new virtual vehicle assembly when the powertrain from the first vehicle is installed in the body of the second vehicle.

Noise and vibration evaluation of driveline clunk can be challenging as it is the result of driver input conditions and is transient in nature. As with many noise and vibration challenges, the use of computer-aided engineering (CAE) simulation is useful as it allows for detailed study of the phenomenon and prediction of potential improvements. A hybrid approach of physical test-based measurements and CAE analysis can be used to leverage the advantages of CAE in a comprehensive evaluation including the total vehicle noise, vibration, and harshness (NVH) performance. In this paper we present work performed to facilitate engineering evaluations of driveline clunk using both measured test and CAE simulation data. We explain how we used measured test data to inform the CAE analysis, how the simulation approached modelling of the transient clunk event, and how the measured data was used to provide contextual sound for realistic evaluation of the CAE output as heard by the passengers.