Temperature and flow-velocity distributions of the gas in a self-sustained transverse discharge

An experimental study of the distributions of gas temperature and flow velocity in the transverse discharge of an electric-discharge CO2 laser is reported, and the dynamic characteristics and temperature of the gas in the core of the flow are estimated. The temperature at the core of the flow increases with increasing distance from the beginning of the discharge. The temperature flow profile demonstrates that there is a preferential local heating of the gas mixture near the walls. Quantitative analysis of the velocity and temperature of the core of the flow using one-dimensional equations of gas dynamics and the energy balance equation of the gas suggests that the turbulent thermal conductivity in a transverse discharge can transfer heat from the warmer electrode layers to the core of the flow. This mechanism causes further heating of the gas and reduces the gain and efficiency of flow-through lasers with self-sustained transverse discharges.