Development of thermal conductivity measurement for fluids which is convenient and effective for samples near the critical point

A method of thermal conductivity measurement was developed using a thermoelectric module. The measurement is very convenient and simple, and has sufficient accuracy for common gaseous samples and liquids that are not electrically conductive. Moreover, the method is applicable to samples near the critical point and in the supercritical region. The isotherm of the thermal conductivity of CO2 near the critical temperature was measured as an example and the divergence of the values, the so-called "critical enhancement," was observed.