TIME LAG APPROACH FOR MEASURING THERMAL CONDUCTIVITY AND SPECIFIC HEAT

摘要

A method and apparatus for providing a more direct approach to determine the thermal conductivity, thermal diffusivity and specific heat of a fluid of interest, independently of the amplitude of the sensor output. This is preferably accomplished by measuring one or more variable phase or time lags between selected input and output AC signals, and directly deriving the thermal conductivity, thermal diffusivity and specific heat therefrom. Such derivation is therefore less dependent than amplitude-based sensors on occasional or unpredictable drift in sensor resistive elements.