周期的な逆流を形成する脈動噴流による2種類の気体の混合過程（炭酸ガスを静止空気中に噴出した場合）

概要

論文の詳細を見る
A strongly pulsed jet is considered as a method for rapid mixing of two different gases. Carbon dioxide gas with a pulsation was discharged from a convergent and round nozzle into still air. An oscillatory and reversed flow at the nozzle exit was produced by the pulsation with high intensity. The spatial and temporal variations of concentration and velocity were measured in the mixing region of the pulsed jet. The mixing rate of the gases is dramatically enhanced near the nozzle exit. Neither the mean concentration nor the mean velocity monotonically decays in the stream-wise direction, because the ambient air is drawn inside the nozzle periodically by the reversed flow. The direction of the velocity changes periodically at a certain boundary, which is the position where the mean concentration becomes the minimal value. When the mixing gas is aspirated inside the nozzle, the fluid lump of any concentration is separated to two fluid lumps because of the direction change in the velocity. The issuing mean velocity becomes larger than the velocity determined by flow rate of supplied carbon dioxide gas. The axial distribution of the mean velocity increases near the nozzle exit. There is also a phase difference between the concentration and velocity oscillations.