Turbulent mixing measurements using short-duration jets

A short-duration technique developed for characterizing supersonic jet mixing phenomena is described and suggestions are given for adapting the method to ideal, nonreacting jets. A double expansion Ludwieg Tube was used for the jet supply, which issued into the ambient medium. Varying the jet diameter provided control over the flow density, and static pressure and temperature data were collected at various downstream and radial distances from the nozzle. Sample data are provided to illustrate the effects of using premixed gases and of the passage of shock waves on instrument response. Design modifications which were tested for their effectiveness for injecting monodisperse particles into the jet and for measuring the particle number density in supersonic jet flows are described, along with test data.