Behavior of Liquid Droplet Exposed to Air Flow on Disk : In Connection with Mist Flow Injected between Parallel Disks

Abstract

When mist flow is injected from a pipe between horizontal parallel disks, a thin liquid film and liquid droplets are left on the lower disk. The behavior of residual liquid on the disk is studied experimentally. The measured front side or back side contact angle of the liquid droplet exposed to air flow does not agree with the advancing or receding contact angle measured by the falling method. The front side and the back side contact angles are concerned with the advancing contact angle, the receding contact angle of the droplet on the wet disk, and the receding contact angle of the droplet on the dry disk. The gas velocity at the stop position of the droplet agrees well with equilibrium velocity calculated from force balance with the front side and the back side contact angles. The analytical equation for calculating the frequency of the sway of the liquid droplet is proposed.