The Position Stability of Large Water Drops Suspended in a Vertical Wind Tunnel

Abstract

The behavior of water drops of diameter in excess of 3 mm suspended in a vertical wind tunnel is described and the vertical-position stability quantitatively and qualitatively assessed. The contribution to vertical instability caused by measured turbulence is calculated but does not fully account for the degree of instability observed. It is suggested that an inherent instability arises from the airflow constraints required to maintain a drop in the working section of the tunnel. When a drop is retained by such constraints, the artificial conditions under which experiments are performed will limit the applicability of results obtained in the wind tunnel to the atmosphere.