Output details

Aeroacoustic sound generation in simple expansion chambers

Significance of output:

Engine exhaust silencer manufacturers routinely use predictive models to refine the performance of their silencers. However, existing linear models take no account of the often commonplace and problematical aeroacoustic source mechanisms which are fundamentally non-linear in nature. The measurement method described in this paper is used to identify and characterise these sources. It is now being adopted by the automotive exhaust industry in their silencer design (D van der Walt, Bosal, SA). In addition, the application of the nonlinear theory provides these and others in the field with a valuable predictive tool.