B212 噴流の混合促進のPIVとLIFによる計測

抄録

An experimental investigation of vertical and turbulent structure change near a jet mixing flow caused by the lobed nozzle has been conducted. The technique of the Laser Induced Fluorescence (LIF) and Particle Image Velocimetry (PIV) were used to accomplish the flow visualization, instantaneous quantitative concentration measurements and velocity field measurements of the lobed jet mixing flows. Compared with circular jet flow, the lobed jet flow were found to have shorter laminar region, its spanwise Kelvin-Hemholtz vortices paring and combining process was accelerated, small scale turbulent vortices appeared earlier, and the bigger turbulent intensity was found in the lobed jet than that in circular jet flow. All these indicated the mixing enhancement performance of lobed nozzles over the circular nozzle.