THERMAL-CONDUCTIVITY OF BINARY GAS OF THERMAL EXCITATIONS WITH EXTERNAL SCATTERING CENTERS

The effective thermal conductivity of a quantum continious medium cont aining a two-component gas of thermal excitations and scattering cente rs is calculated. The results are valid at any relations between the i nteraction rates of thermal excitations with one another and with scat tering centers. It is shown that, in addition to partial contribution, the coefficient of effective thermal conductivity also contains flow and diffusion terms associated with different physical mechanisms and with distinct physical meaning. The obtained general expressions are u sed for investigation of such systems of thermal excitations in crysta ls and quantum fluids as longitudinal and transverse phonons, phonons and magnons, phonons and rotons. The expressions obtained are compared with the results of other investigations and experiments.