Jet response to pure tone excitation

Turbulence spectra in an axisymmetric air jet subjected to a symmetrical pure tone excitation were measured. Measurements were carried out in the mixing region and the transition region of the jet. The experimental investigation suggests that the ratio of the excitation Strouhal number St sub e to the preferred jet Strouhal number St sub d (corresponding to dominant frequency in the jet core) governs the development of the turbulence of the jet flow field.