PRECESSION STROUHAL NUMBERS OF A SELF-EXCITED PRECESSING JET

The self-excited precessing jet (PJ) nozzle has been the subject of research and development for industrial applications since the discovery of naturally occurring precession of a jet partially confined in a relatively large chamber [1]. In this paper we first report how the nozzle chamber length and the jet inlet Reynolds number influence the frequency (f_p) of jet precession and then seek a method of forming an appropriate Strouhal number of the precession which can effectively describe turbulent mixing in the flow downstream from the nozzle.