Treelike thermal structures on the water surface

Abstract

Unusual treelike thermal structures can be formed on the free surface of the evaporating water in small containers. These structures are studied in detail for the first time, and it has been established that under certain parameters (the container diameter is about 90 mm, the water layer thickness is 6–15 mm, and the container wall temperature is 28–47 °C), they are the most probable and pronounced. The presence of both horizontal and vertical temperature gradients is fundamental for the formation of such structures. An attempt has been made to numerically model treelike structures. It is shown that the classical model of heat and mass transfer in a fluid, taking into account the mechanisms of heat transfer on the free surface, usually used for water, and the reference coefficient of the surface tension of water, does not even allow one to qualitatively predict the observed treelike structures on the water surface. A hypothesis about the need to consider the influence of impurities on heat and mass transfer near the water surface has been proposed.