Electrical and Thermal Conductivity and Radiation Power of Air Measured at 1-30ATM and 6500-11500 K.

摘要

Experimental results are reported on the electrical and thermal conductivities and the radiative properties of air plasma at pressures of 1, 6 and 30 atm. in the temperature range 6,500 K to 11,500 K. A wall-stabilized steady cascade arc was used to provide a cylindrically symmetric column of air plasma. The electrodes were bathed in argon. The electrically floating wall plates were used to determine the electric field strength in the column. Side-on optical measurements of the lateral intensity profile using the oxygen 844.6 nm line and the nearby continuum permitted the deduction of the radial temperature profile using the Abel Inversion. Total radiation per unit arc length for wavelengths transmitted through a quartz window was measured by a thermopile. Temperature dependent trial functions of electrical conductivity and radiation strength per unit volume were optimized by computer to fit the experimental data. Thermal conductivity was then obtained from the energy balance. The experimental results agree well with the existing experiments and theories at 1 atm. At the higher pressures, the experiments are original and compare favorably to theory. (Author)