The accuracy of laser flash analysis explored by finite element method and numerical fitting
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Laser flash analysis (LFA) has become over the last decades a widely used standard technique to measure the thermal diffusivity of bulk materials under various conditions like different gases, atmospheric pressures, and temperatures. A curve fitting procedure forms the heart of LFA. This procedure bases on a mathematical model that should ideally account for inherent shortcomings of the experimental realization such as: duration of the heating pulse, heat losses to the environment and sample holder, non-opaque samples, and radiative heat transfer. The accuracy of the mathematical model and curve fitting algorithm underlying LFA defines an upper bound of the accuracy of LFA in general. Unfortunately, not much is known about the range of parameters and conditions for which this accuracy is acceptable. In this paper, we examine the limits of accuracy of LFA resulting from its underlying computational framework. To this end, we developed a particularly accurate and comprehensive computational framework and applied it to data from simulated experiments. We quantify the impact of different (simulated) experimental conditions on the accuracy of the results by comparing the fit results of our computational framework to the known simulation input parameters. This way we demonstrate that a state-of-the-art computational framework for LFA admits determining thermal conductivities of materials in a broad range from at least 0.16 W/mK to 238 W/mK with relative errors typically well below 4% even in the presence of common undesired experimental side effects.
This project was funded by the Lichtenberg Professorship provided by the Volkswagen Foundation.
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Conflict of interest
On behalf of all authors, the corresponding author states that there is no conflict of interest.
- 2.Righini F, Cezairliyan A (1973) Pulse method of thermal diffusivity measurements. High Temp-High Press 5:481–501Google Scholar
- 3.Degiovanni A (1977) Diffusivité et méthode flash. Rev Gen Therm 185:420–442Google Scholar
- 5.Balageas DL (1989) Thermal diffusivity measurement by pulsed methods. High Temp-High Press 21:85–96Google Scholar
- 6.Maglić K, Taylor R (1992) The apparatus for thermal diffusivity measurement by the laser pulse method. In: Compendium of thermophysical property measurement methods. Springer, pp 281–314Google Scholar
- 9.Vozár L (2001) Flash method for thermal diffusivity measurement: theory and praxis. Constantine the Philosopher University, NitraGoogle Scholar
- 14.Li T, Song J, Zhao X, Yang Z, Pastel G, Xu S, Jia C, Dai J, Chen C, Gong A, Jiang F, Yao Y, Fan T, Yang B, Wågberg L, Yang R, Hu L (2018) Anisotropic, lightweight, strong, and super thermally insulating nanowood with naturally aligned nanocellulose. Sci Adv 4(3):eaar3724. https://doi.org/10.1126/sciadv.aar3724 CrossRefGoogle Scholar
- 22.Degiovanni A (1985) Identification de la diffusivité thermique par l’utilisation des moments temporels partiels. High Temp-High Press 17:683–689Google Scholar
- 26.Taylor RE, Clark LM III (1974) Finite pulse time effects in flash diffusivity method. High Temp-High Press 6:65–72Google Scholar
- 37.Hahn O, Raether F, Arduini-Schuster MC, Fricke J (1997) Transient coupled conductive/radiative heat transfer in absorbing, emitting and scattering media: application to laser-flash measurements on ceramic materials. Int J Heat Mass Transf 40(3):689–698. https://doi.org/10.1016/0017-9310(96)00137-8 CrossRefGoogle Scholar