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Effect of electrostatic field on the heat-mass exchange processes at the metal vacuum 

       Degassing - the traditional method of degassing of liquid metal. In order to accelerate the melt blow an inert gas [1]. Using the electrostatic field in the vacuum have been possible in several directions. First, in order to intensify the vacuum, because electrostatic field of negative potential, while significant tension breaks positively charged particles of gas removed from the metal mirrors (5-30kV potential at distances 1.7sm electrode surface of a still from the melt [2]). Secondly, as an indicator for the completion of the degassing under low tension of the field at the metal mirror [3]. Using the electrostatic field, as such, virtually no effect on the distribution of hydrogen atoms removed at the border «vacuum-metal», but also leads to energy savings. Field moderate tension only redistributes the particles of this border. The latter is a considerable interest, because for moving (under the influence of an inert gas purge) metal, this process is investigated for the first time. The nature of the distribution of charged particles on the surface of the gas removed the metal depends both on the electrode shape and intensity of electric field, and the speed of the melt at the border and affect the diffusion process of metal, especially near the boundary of «the vacuum-metal». Accounting for this effect is achieved by setting the boundary conditions of convective diffusion equation: 



      Convective diffusion equation (1) must be supplemented by equations of convective heat conduction and hydrodynamics. When moving a mirror on the metal electrode is observed a continuous sequence of hydrogen redistribution of charged particles on the boundary under the influence of the field electrode. The particles at any time seek to equilibrium with the external field. This leads to the surface electric current, which is technically difficult to measure. Induction of this current can be characterized as «electrodynamic induction», which degenerates into the usual electrostatic approaching zero velocity of the melt to the source of the electrostatic field. The proposed mechanism for the transfer, presented in papers [4,5] and developed by one of the authors, under the leadership of Distinguished Scientist and Technologist of Ukraine professor. Dyudkina DA lies in the explanation of the theory and experimentally detected by the new electric effect has been promising [6]. If the limiting point mass in the vacuum degassing of metal in a kinetic level, the electrostatic field, redistributing gas atoms removed the surface of metal, can contribute to education centers of desorption of this gas in the cavity vakuumatora [7,8]. Theoretical model [4,6] developed for the case of accomplishments in the electrodynamic balance, when a «hold» Some removed the gas particles on the mirror metal is accompanied by the loss of others. At the interfaces of these particles are formed clots. Property of their electric field is balanced by an external field. Depending on the rate of relaxation processes determined by speed of the melt, before the clots ions will be more or less blurred. With very high (theoretically, infinite) speed of relaxation is a dynamic equilibrium in the system. Thus, the static equilibrium of the charges in the electrostatic induction is replaced by the dynamic of this phenomenon. Let the deviation of the real concentration C / n removed the gas at any point on the border «vacuum-metal» equilibrium of C n determined by the methods [4,6], for the chaotic motion of these ions is subject to the normal distribution law: 



      The probability of getting C / n in the set of values [9]: 



       As a result, we have: 



      where, obviously, K (0) = 3 and K / (0) is determined either theoretically or experimentally. 
      Ie The problem of setting the boundary condition for the equation of convective diffusion on the boundary of «metal vacuum» in terms of simultaneous exposure to melt the vacuum, inert gas purge, and an electrostatic field. The expression for C n the concentration of metal removed from the gas at the boundary of the given ratio, including the partial pressure of the gas in the cavity vakuumatora, the tension of electric field and the tangent component of velocity of the melt at this boundary. When = 0 and = 0, the ratio degenerates into a well-known law Sivertsa square root, and thus is a generalization. Argued that to determine the specific type of the base relations must be brought to the new data, considered in the work, electrical effects. In the development of generalized relations (2) and the need to focus the efforts of scientists. An assessment of the value the confidence interval for the values of the deviations of C n from the dynamic equilibrium values on the basis of probability theory.