Processes and Heat Transfer in Electrodischarge Chamber

Abstract

Investigation of the processes in the discharge chambers of plasma generators is complicated by the absence of optical windows , which are necessary for determining the main characteristics of the arc such as dimensions, optical characteristics , and nature of motion. The point is that to obtain limiting plasma parameters, the ultimate strength of the discharge chamber is necessary, whereas the openings for optical windows are concentrators of mechanical stresses, which substantially reduce the strength of the discharge chamber of the plasma generator [1, 2]. Naturally, in the absence of data of optical measurements , such parameters as temperature, electric field intensity in the arc, current density, etc., can be estimated only using various assumptions. Therefore, numerical estimations of the above parameters at the large-scale experiments were performed based on indirect data obtained by measuring current, voltage and pulsed pressure, and by visual and instrumental monitoring of the state of the electrodes and other elements of the generator before and after experiment. Based on these data, it is possible with a high degree of reliability to make conclusions about such parameters as discharge current and voltage drop across the arc, discharge power, arc resistance, electric charge, inputted electric energy in the arc, integral specific erosion of electrodes. With somewhat lesser degree of reliability, one can make conclusions about concentration and aggregate state of the products of erosion of electrodes and their quantitative ratio, average temperature, and internal energy of the operating gas. With even less reliability, we can conclude about the electric field intensity, current density in the arc, optical, and dynamic characteristics of the arc.