Reduction of supersonic jet noise using micro-jets in the diverging part of a conical CD-nozzle
Paper i proceeding, 2015

Reducing the radiated noise from supersonic jets with maintained thrust is a major challenge. An LES/CAA method and experiments are uti- lized to investigate the flow field and the far-field acoustics of a supersonic jet emitted from a circular CD-nozzle with a sharp throat. Air is injected into the divergent section of the nozzle using 12 evenly distributed micro-jets around the nozzle circumference and the change in total thrust and acoustic signa- ture is investigated. The micro-jets are shown to decrease shock-strength with increased injection until an optimum point where further increase in injection mass flow caused increased shock-strength. As a consequence of the reduced shock strength, the far-field shock-noise was decreased. The net thrust was shown to increase with increased injection mass flow, whereas the specific thrust was slightly decreased. Micro-jet injection into the divergent section of a CD-nozzle appears, therefore, to be an effective configuration for reduced shock-noise radiation from supersonic jets.


Haukur Hafsteinsson

Chalmers, Tillämpad mekanik, Strömningslära

Niklas Andersson

Chalmers, Tillämpad mekanik, Strömningslära

Daniel Cuppoletti

Ephraim Gutmark

The International Conference on Jets, Wakes and Separated Flows (ICJWSF2015), June 16-18, 2015, Stockholm, Sweden


Hållbar utveckling




Strömningsmekanik och akustik