DETERMINATION OF THERMAL CONDUCTIVITY OF GASES FROM HEAT TRANSFER MEASUREMENTS IN THE TEMPERATURE-JUMP REGIME.

The thermal conductivity values are computed for helium and neon in the temperature range 500 degree -2500 degree K from heat transfer data taken in the temperature-jump regime employing a hot-wire type column instrument. These apparent pressure dependent conductivity values are corrected for the temperature-jump effect according to kinetic theory in conjunction with experimentally determined thermal accommodation coefficients. These corrected conductivity values are pressure independent and are in good agreement with the values calculated from heat transfer data in the continuum regime. This is regarded as sufficient evidence validating the kinetic theory model for heat transfer in the temperature-jump region and for the experimentally determined thermal accommodation coefficients.