MATHEMATICAL MODELING OF THE STEFAN'S PROBLEMS WITH THE DETERMINATION OF THE COORDINATES AND THE VELOCITIES OF THE DYNAMICALLY MOVING BORDERS OF PHASE TRANSFORMATIONS
Journal Title: Periódico Tchê Química - Year 2018, Vol 15, Issue 0
Abstract
Dynamic problem of heat conduction in multiphase media with many dynamically moving boundaries of phase transformations, the coordinates and velocities of which are not known in advance and are determined based on experience considering heat flow balances at moving boundaries of phase transformations after determining the temperature fields inside each phase. The urgency of this kind of problem is explained by the various problems of designing thermal protection from composite materials for hypersonic aircrafts upon absorption of thermal energy due to physical and chemical transformations in area constrained by dynamically moving boundaries. Determining the coordinates and velocities of the moving boundaries of phase ransformations is reduced to solving a system of transcendental equations in an amount equal to the number of dynamically moving boundaries. Examples of calculations are given below.
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