Jet Pipe

Application ID: 1844

This example models the radiation of fan noise from the annular duct of a turbofan aeroengine. When the jet stream exits the duct, a vortex sheet appears along the extension of the duct wall due to the surrounding air moving at a lower speed. The near field on both sides of the vortex sheet is calculated.

The linearized Potential Flow physics interface in the Acoustics Module describes acoustic waves in a moving fluid. However, the field equation is only valid when the velocity field is irrotational, a condition that is not satisfied across a vortex sheet. As a consequence, the velocity potential is discontinuous across this sheet. To model this discontinuity you use the special Vortex Sheet boundary condition.

This model example illustrates applications of this type that would nominally be built using the following products: