HEAT CONDUCTIVITY MEASURING METHOD AND APPARATUS

PROBLEM TO BE SOLVED: To realize a novel heat conductivity measuring apparatus enabling the accurate measurment of heat conductivity in the vicinity of a critical point. SOLUTION: A thermoelectric module 2 equipped with a Peltier element is inserted in a fluid sample of which the heat conductivity must be measured and a constant current is allowed to flow to the thermoelectic module to generate temp. difference between both therminals of the thermolectric module and, in such a state that the temp. difference is converged to a steady value, the voltage ΔV generated across both terminals of the thermoelectric module 2 is measured as the sum of the electromotive force Δ Vz due to the temp. difference and the voltage drop due to an internal resistor R and the heat conductivity of a sample is calculated on the basis of a current value I, the measured voltage value Δ V, the foreknown internal resistance value R and the temp. T. of the sample.