NON-EQUILIBRIUM EFFECTS ON CONDUCTIVITY AND ELECTRODE HEAT TRANSFER IN IONIZED GASES. Technical Note No. 4
A simple theory of non-equilibrium conduction in ionized gases was developed, which accounts for the elevation of the electron temperature by energy gain in the electric field. It is assumed that the ionization is in equilibrium at the electron temperature. The theory yields a modified Ohm's law, such that the current density varies as a power of the electric field. The power is unity for gases at high temperatures, but can be very large at low gas temperatures. Measurements carried out with hot tantalum electrodes in an argon-potassium plasma at 1500 to 2500 deg K, at atmospheric pressure, agree with the predicted variations of the conductivity with both current density and gas temperature. This is regarded as a verification of the assumption of ionization equilibrium at the electron temperature. Both the theory and experiments indicate that the augmentation of electrode heat transfer by Joule heating in the boundary layer is less important than equilibrium theory predicts it to be. (auth)
- Research Organization:
- California Inst. of Tech., Pasadena. Guggenheim Jet Propulsion Center
- NSA Number:
- NSA-15-026991
- OSTI ID:
- 4843920
- Report Number(s):
- AFOSR-165
- Country of Publication:
- United States
- Language:
- English
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