CD-adapco and Exa Corporation were invited two years ago to participate in the programme for aeroacoustics simulation of duct flow noise and sunroof buffeting. The Working Group has invested significant resources to acquire experimental data on an elbow-bend / flap configuration and generic sunroof model, including pressure spectra, mean and dynamic flow visualization.

CD-adapco has demonstrated through STAR-CD a well-defined and repeatable process, the quality of the predictions being high enough to capture performance trends if not absolute decibel levels from the flow noise-generating mechanisms. The key to success is shown to be in the understanding of the flow phenomena and consistent setting of simulation parameters, including non-reflective inflow boundary treatments and high-order turbulence modeling akin to LES (large eddy simulation).