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Results of experimental investigation of the heat exchange in a plasma module which incorporates a mixing chamber and three plasmatrons operating on it are generalized by the methods of physical modeling with the use of regression analysis. It is shown that the heat exchange in such a system is determined by the processes occurring in arc heaters. The most substantial influence is exerted by convection and radiation. [ABSTRACT FROM AUTHOR]

An experimental investigation of the electric-field strength along the length of a cascade argon at a pressure lower than atmospheric pressure has been performed. The influence of different processes on the formation of the voltage-current and E-I characteristics of the arc was considered. It is shown that the processes of heat transfer are of primary importance; however, in the region of mixing of the cathode jet with the heated gas the Reynolds number has a marked influence. The generalized characteristics of the voltage across the arc, of the near-electrode voltage drop, and of the electric field strength averaged over the length are presented. [ABSTRACT FROM AUTHOR]

By methods of physical modeling using a linear ridge regression it is established that in direct-current plasmatrons with step electrodes the volt-ampere characteristic of the arc is formed by heat-transfer processes, while gasdynamic factors have a slight effect. Generalized VACs of unilateral- and bilateral-emission plasmatrons in blowing the arc with air and hydrogen are refined. [ABSTRACT FROM AUTHOR]

Using the methods of regression analysis, consideration is given to the influence of various processes on the volt-ampere characteristics (VAC) of an arc discharge in a plasma generator with a hot rod cathode and a cold cylindrical anode with an arc length that is self-adjusting due to the mechanism of shunting. It is shown that heat-transfer processes play a dominant role in VAC formation. [ABSTRACT FROM AUTHOR]

Special features of physical modeling of high-current arc discharges are considered. It is shown that the employment of dimensionless criterial expressions makes it possible to establish only approximate similarity of characteristics for some specific apparatuses which govern arc-discharge conditions. Procedures to select the dominant energy-exchange processes and to find the scale values of plasma properties are presented, whose knowledge permits modeling of the discharges initiated in various media. [ABSTRACT FROM AUTHOR]

A successive selection of the dominant variables in a generalized volt-ampere characteristic of a magnetomovable arc is performed by regression-analysis methods. It is shown that turbulent energy transfer increases in importance with the electrode gap and magnetic induction. [ABSTRACT FROM AUTHOR]

For arcs that are initiated in an air medium in rotation in a ventilated annular gap and move along parallel electrodes under the action of an external magnetic field, the influence of the magnitude of the interelectrode gap and magnetic induction on the discharge voltage is considered. The accuracy of the volt-ampere characteristics of the arc in approximating by means of simple empirical power formulas and with the use of criterial relations between generalized variables is estimated. [ABSTRACT FROM AUTHOR]

The effect of the conditions of electric-arc burning in an air flow on the process of thermal destabilization is considered. The considerable role of heat-transfer processes in the development of instability in an arc-discharge column is shown. [ABSTRACT FROM AUTHOR]

Statistical methods of analysis are used to study the influence of a change in the electrode diameter on the accuracy of the volt-ampere characteristics (VACs) of a vortex electric-arc plasmatron operating with technical nitrogen. It is shown that when each initial parameter is allowed for separately and the VACs are represented by an empirical formula, the influence of a change in the diameter is insignificant. When all the initial parameters are allowed for simultaneously in one dominant criterion in the case of approximation of VACs by a generalized expression, the effect of the size factor proves to be substantial. [ABSTRACT FROM AUTHOR]

The influence of heat transfer processes in arc discharges on the development of thermal instability is considered. A substantial dependence of the process of destabilization on the plasma properties is shown by the example of argon and helium arcs. [ABSTRACT FROM AUTHOR]