Experimental estimation of characteristic times of the existence of liquid drops in the form of a sphere and ellipse upon their movement in a gas environment under the conditions of moderate weber numbers

Abstract

The experimental procedure has been developed and studies using high speed (10 5 frames per sec ond) system of cross correlation video registration of a change in the shape of drops for the most typical liq uids that are widely used in various chemical technologies (water, kerosene, and ethyl alcohol) have been car ried out. The liquids move with significantly subsonic speeds (up to 5 m/s) in the air environment under the influence of gravitational forces. The initial sizes of drops varied in the range of 3-6 mm. The cyclic nature of the changes in the shapes of drops during movement has been established. Characteristic times of transi tions from one shape of drop to another have been measured. Characteristic times of the existence of drops in the form of spheres and ellipses have been defined. Recommendations about the use of geometrical models of liquid drops for theoretical study of heat and mass transfer and hydrodynamics in the course of their move ment through gas environments under the conditions of moderate Weber numbers have been formulated.