Nonequilibrium Hydrogen Positive Columns and State Transitions by Two-Temperature Model

Abstract

Global properties of nonequilibrium hydrogen positive columns are obtained in a range 1.0–0.1 cm of a tube radius and at moderately high pressure (1.0 and 0.1 atms) by computer simulation based on a two-temperature model. The hydrogen positive column itself has two stable states, an arc and a glow, and one unstable state. When a tube radius and/or a pressure decreases to a certain value, the arc region joins continuously to a glow region. If we use the experimental data of thermal conductivity of hydrogen gas, the results considerably deviate from the results by using the theoretical data. Mechanisms of existence of multiple states, of state transitions, and of parameter dependence of the global properties are explained.