THERMAL-CONDUCTIVITY OF N-2, CH4 AND CO2 AT ROOM-TEMPERATURE AND AT PRESSURES UP TO 35-MPA

The thermal conductivity of gaseous nitrogen, methane and carbon dioxide has been measured at room temperature and at pressures up to 35 MPa in the cases of nitrogen and methane and up to 5 MPa in the case of carbon dioxide. A transient hot-wire technique was used, which has been described previously. The curves of thermal conductivity versus density for all three gases are found not to be expressible as a polynomial expansion, which is probably due to changes in energy-relaxation behavior with pressure. In the case of carbon dioxide, which was studied close to its critical temperature, some vestiges of anomalous behavior associated with the critical point can be seen. Accurate Eucken factors for the three gases are given. In the case of nitrogen, the experimental value is found to be somewhat below recent predictions. © 1979.