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Knowledge of thermophysical properties is a major challenge to the numerical modeling of heat transfer in liquids. In the present paper, a novel experimental technique is implemented to measure these characteristics. This technique consists on exciting the front face of a three layered sample with a crenel heat flux and measuring the temperature response on the rear face. The three layered sample is formed by a Teflon cell filled with liquid and covered by two copper layers on its front and rear faces.
A 1D dimensional model is developed to simulate conductive heat transfer in the sample. The thermophysical parameters are estimated by minimizing the OLS norm referring to the difference between calculated temperatures and the measured signal. This minimization is performed by the Gauss-Newton method. The effective thermal conductivity and the biot number are estimated for two different liquids. The parameter uncertainty is analyzed and a good agreement with literature values is obtained.
liquids, conductive heat transfer, thermal characterization, parameter estimation, photothermal technique.
[1] Blackwell J.H., A transient flow method of determination of thermal constants of insulating materials in bulk, Part I—theory, J. Appl. Phys, 1954, vol. 25(2), pp. 137-144.
[2] Remy B, Degiovanni A. Parameters estimation and measurement of thermophysical properties of liquids. Int J Heat Mass Transfer, 2005; vol. 48, pp.4103–4120.
[3] Remy B, Degiovanni A. Measurement of the thermal conductivity and thermal diffusivity of liquids. Part II: Conductive and radiative effects. Int J Thermophysics, 2008; vol. 27, pp.949-969
[4] Coquard R., Panel B. Adaptation of the FLASH method to the measurement of the thermal conductivity of liquids or pasty materials, International Journal of Thermal Sciences, 2009, vol 48, Issue 4, pp. 747-760
[5] Maillet D, Degiovanni A, Batsale JC, Moyne C, Andre S. Thermal Quadrupoles : An Efficient Method for solving the Heat Equation through Integral Transforms. New York: John Wiley & Sons, 2000.
[6] Beck J. V, Arnold K. J. Parameter estimation in engineering and science. New York: John Wiley & Sons, 1977.
[7] Kuntner J, Chabicovsky R, and Jakoby B. Sensing the thermal conductivity of deteriorated mineral oils using a hotfilm microsensor. J Sensors and Actuators 2005, vol 123, pp.397-402.