Pulsed laser measurements of particle and vapour concentrations in a turbulent jet

A turbulent jet of air has been seeded with both particles and a vapour. An excimer pumped dye laser excited visible fluorescence from the biacetyl vapour and Mie scattering from the micron-size particles. It was possible to measure the simultaneous scattering from both phases by using interference filters to separate the signals. It has been found that the biacetyl vapour provides an adequate tracer for measurements of the concentration field in a turbulent flow. Furthermore, the feasibility of making simultanous concentration measurements of two phases in a turbulent flow has been demonstrated.