Growth of Disturbance Wave Induced by Radial Liquid Sheet Instability(<Special Issue>Jets, Wakes and Separated Flows)

The growth and three-dimensional deformation of a disturbance wave in the laminarturbulent transition of a radial liquid sheet flow are studied. The radial liquid sheet is formed by the release of a radial liquid film flowing on a disk from the edge of the disk to still air. When the Reynolds number is large, a concentric disturbance wave appears and grows downstream on the free surfaces of the liquid sheet. The disturbance wave is induced by an unstable disturbance attributed to an inflectional velocity profile inside the liquid sheet. The detailed observation of a disturbance wave excited by a supersonic wave reveals the growth and three-dimensional deformation of the disturbance wave.