DYNAMICS OF THE CRYSTALLIZATION FRONT INDUCED BY THE TEMPERATURE GRADIENT AT THE UPPER BOUNDARY OF A HORIZONTAL LAYER OF A FLUID
V. A. Arbuzov1,2, E. V. Arbuzov3,2, Yu. N. Dubnishchev1,2, V. S. Berdnikov1,2, O. S. Melekhina2
1Kutateladze Institute of Thermophysics, Siberian Branch, Russian Academy of Sciences, 630090, Novosibirsk, prosp. Akademika Lavrent'eva, 1
2Novosibirsk State Technical University, 630073, Novosibirsk, prosp. K. Marksa, 20
3Sobolev Institute of Mathematics, Siberian Branch, Russian Academy of Sciences, 630090, Novosibirsk, prosp. Akademika Koptyuga, 4
Keywords: оптическая диагностика потоков, гильберт-оптика, конвекция в системе вода-лёд, фазовый переход в переохлаждённой жидкости, волна кристаллизации, optical diagnostics of flows, Hilbert optics, convection in the water-ice system, phase transition in a supercooled fluid, crystallization wave
Abstract
The dynamics of the crystallization front induced by the temperature gradient at the upper boundary of a horizontal layer of water bounded by flat thermostatted surfaces is studied. The formation and evolution of convective structures are visualized by methods of the Hilbert optics and digital video recording. The difference in the temperatures of the upper ( T1) and lower ( T2) thermostats satisfies the condition T 1 < T2. In this system, the temperature of the cooled upper surface is an order parameter. Reaching a critical value of this parameter leads to a bifurcation phase transition from the liquid state (supercooled water) to the solid state (ice). The velocity and shape of the crystallization wave front are determined. The spatial-temporal state of the crystallization wave is found, in which the wave front shape is a line of equal velocities. The dynamic profile of the isothermal surface bounding the spatial shape of the solid phase is visualized.
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