The effective thermal conductivity of highly porous metal foams is measured using a photothermal method with a crenel heating excitation. This method is based on a nondestructive technique. The foam is sandwiched between two thin aluminum plates. The front face of the three-layered structure is submitted to a heat flux and the temperature rise on the rear face is recorded using an infrared camera. Measurements are reported on several foams. The parameter identification is performed by the minimization of the ordinary least squares objective function comparing the measured temperatures to the response of a thermal model function of thermophysical parameters, built with thermal quadruple formalism. The used iterative algorithm is based on the Gauss-Newton method. The obtained results are compared to the literature values and a good agreement is noted.
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