This article presents a method for measuring the thermal conductivity of building materials using the asymmetric hot wire technique in transient conditions. Two approaches for estimating thermal conductivity are developed: one based on a simplified model and the other on a quadripolar model. These methods were applied to various cases of materials simulated in COMSOL. The results of the theoretical study show that thermal conductivity can be estimated with an accuracy of less than 1% using the quadripolar model. On the other hand, the simplified model shows much greater deviations from the quadripolar model, particularly for highly insulating and lightweight materials with a conductivity between 0.025 and 0.048 W？m？1？K？1. Experimental studies conducted on various building materials and bulk products (powders and aggregates) confirmed the accuracy of the results obtained in the COMSOL simulations. A comparison between the thermal conductivity values measured using the asymmetric hot wire method on three validation samples and those derived from the effusivity measurement using the asymmetric hot plate method, coupled with the thermal diffusivity obtained using the 3L method, revealed a deviation of less than 1.5%.
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