Thermal properties determination of a cylindrical product during its cooling: two-dimensional numerical model and uncertainty

• Published in: International journal of food properties 2019-01, Vol.22 (1), p.343-354
• Main Authors: da Silva, Wilton Pereira, D. P. S. e Silva, Cleide Maria, De Souto, Leidjane Matos, Gomes, Josivanda Palmeira, J. M. Queiroz, Alexandre, De Figueiredo, Rossana M. F.
• Format: Article
• Language: English
• Subjects: convective heat transfer coefficient; Cooling; covariance matrix; Heat transfer; numerical solution; Simulation; Thermal diffusivity; uncertainties
• ISSN: 1094-2912; 1532-2386
• DOI: 10.1080/10942912.2019.1578791

In this article, a two-dimensional model is proposed to determine thermal diffusivity and convective heat transfer coefficient, providing the average values, their uncertainties and the covariance matrix referring to these parameters for a product with cylindrical geometry during its cooling. The proposed model used a two-dimensional numerical solution of the diffusion equation for the direct problem; an experimental dataset referring to the cooling kinetics in the center of the product and an optimizer program based on the Levenberg-Marquardt algorithm for the inverse problem. The model was used with success to determine the thermal properties, their uncertainties and the covariance matrix of a cucumber during its cooling. The obtained results allowed establishing a confidence band that made it possible to graphically evaluate the precision of a new simulation for a cucumber with different dimensions.