円形噴流の渦輪の合体へのレイノルズ数の影響

抄録

The aim of this study is to merge vortex rings in the initial region of a round jet. Air is issuing from a round nozzle into still air. The jet Reynolds number at the nozzle exit condition is set to from 1000 to 10000. The stream wise cross-section on the jet centerline was visualized by a planer laser Mie-scattering (PLMS) method and recorded by a high-speed camera. For the jets at Reynolds number when the merging of vortex rings occur in the natural transition, the merging of four vortex rings is achieved by applying an acoustic disturbance with the frequency of vortex formation. The merging process of the vortex rings is observed from the visualized images, and the spatial distribution of the merging of the vortex rings is created and compared with the Reynolds number.