APPLICATIONS OF THREE-DIMENSIONAL LIF TO PLUME FLOWS

摘要

A new three-dimensional Laser-Induced Fluorescence (LIF) system is described. The system is capable of measuring three-dimensional concentration fields continuously and almost instantaneously. It is particularly designed for studies of jet or plume mixing in stratified and unstratified, stationary or flowing environments. Applications of this system to various plume flows are presented. In this paper we report measurements on vertical and horizontal round buoyant jets in stratified and unstratified crossflows. The horizontal buoyant jets discharge orthogonal to the crossflow so that the plume trajectory is three-dimensional. Three-dimensional visualizations of jets were reconstructed from a serious of slices, which show familiar shapes and trajectories. Trajectories of jets and variation of dilution along the trajectory were extracted. The results fit previous study well and show the effect of nozzle orientation clearly.