A miniaturized transient hot-wire device for measuring thermal conductivity of non-conductive fluids

This paper presents the design, fabrication and characterization of a novel transient hot-wire device for measurement of thermal conductivity of non-conductive fluids. The key features of the cell are small sample amount, simple fabrication, accurate measurement and transparency, which allows the study of both thermal and optical properties of the fluids. A 20 μm-diameter platinum hot wire is symmetrically suspended along the central axis of the capsulated cell to avoid the effect from the walls. A four-point resistance measurement method was used to measure the transient resistance with high accuracy. The accuracy of the thermal conductivity measurement was validated with reference values and very good agreement was achieved.