Abstract:Based on the traditional transient hot-bridge sensor, a new unsymmetrical model to measure thermal conductivity—the transient hot-strip method of constant power is proposed. This model insulated the heat source and the thermometer, eliminating the influence of self-heating from strips and the ambient temperature variations. By measuring the voltage change verse time, the thermal conductivity of the material can be obtained accurately. With this method, the corresponding heat sensor is designed, and the auto measurement platform of experimental system based on LabVIEW is established. By using this platform, the thermal conductivities of several normal materials are tested. Satisfactory consistent between the values obtained here and the reference values, the relative deviation is about 3%, and the validity of the theoretical model is verified.
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