Experimental Sensitivity Analysis of a Hydrodynamically Self-excited Low-Density Axisymmetric Jet

We report preliminary findings from an experiment on the passive control of a hydrodynamically self-excited low-density axisymmetric jet. The control element that we use is a thin axisymmetric ring. We position this ring at different locations around the jet wavemaker and measure the response with a hot wire. We present our findings via sensitivity maps of the global frequency and the limit-cycle amplitude, and compare these to predictions from linear global instability analysis.