Thermal diffusivity identification by 2 nde derivative analysis of transient temperature profile

International audienceThis paper deals with a new method to identify the thermal diffusivity of isotropic materials. Contrary to the flash method, a continuous and constant heating is applied on the rear surface of the sample. An analytical solution of the 1-D transient equation is developed based on Green's function and gives the temperature profile on the opposite surface at the first moments. Regarding the 2 nde derivative of this equation, we found that it reaches a maximum value at a characteristic time tc 2nde which is proportional to the thermal diffusivity α and the sample thickness es. Experiments are performed on a well-known material, ARMCO Iron, to check the feasibility and the accuracy of the identification with noisy temperature measurements. The method is also applied to insulation materials. Uncertainties on the identified values are discussed and rules are given t

Histoire de la physique

French text publication of the manuscript of the English article en-titled "Physics, History of" and published by Duhem in Volume 12 of the 1911 "Catholic Encyclopedia"

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