Control of jets expansion by impeding jets

The principle retained to control the expansion of a jet, is based here on the generation of streamwise vorticity by impeding jets. Experiments are pe rformed in the mixing layer of two coaxial jets. The rectangular control je ts are placed all around the main jet. A parametric study is carried out, t aking into account the number of control jets, their orientation, and the m ass flow injected. The deformation of the main jet is analyzed from velocit y and temperature fields. A particular configuration is detailed, in terms of turbulence, by using four hot wires probe measurements.