V.I. Volkov, D.Yu. Kozlov, E.R. Kirkolup
Research of the liquid motion dynamics in a capillary
In the given work they made the experiments on dynamics of filling of glass capillaries by diameters: 0,31; 0,34; 0,59 and 0,94 mm with spirit 96%. It was made the attempt of reception not only of a numerical decision of the liquid wicking equation in a capillary, but also of an analytical analogue, which will allow to predict dynamics of capillary movement. From comparison of the exact decision and experimental data of follows, that the profile of speed at the liquid wicking in a capillary has a rather #sharp# kind. The Unique force lifting a liquid upwards on a capillary against the gravity is the force of adhesion between a liquid and a wall of a capillary, and this force is distributed near a surface. Hence, it is possible to assume, that the speed of a liquid near a wall of a cylindrical capillary has the maximal meaning essentially exceeding an average meaning of speed, as well as the speed at the centre of a capillary. Besides, it was possible to construct the approximate analytical decision of the non
linear equation of process of filling of a cylindrical capillary by a liquid and to receive a satisfactory accord of the numerical and the approximate decisions with experimental data.