Determinação da difusividade térmica (e sua incerteza) para produtos acondicionados em recipientes cilíndricos durante seu aquecimento: experimentação, otimização e simulação.

Abstract

This study is based on a theoretical / experimental approach to the description of heat transfer during the heating process of products (agar gel, tomato puree and cashew pulp) in the pasty state, by determining their apparent thermal diffusivity, whereas conduction is the only means of transferring thermal energy. For this purpose, only the cashew pulp heating experiment was carried out, in which the product was placed in a cylindrical container, which was immersed in water previously heated to a temperature of 65oC, and heating data were used for the other products performed. Therefore, a thermocouple was previously placed in the center of the cylinder and another in the inner wall of the pool. As these points were measured every second from room temperature to thermal equilibrium using automatic data acquisition. From this feat, a solver was created, which is an executable program containing the analytical solution of the diffusion equation for cylindrical geometry, the solution to the so-called direct heat diffusion problems, which requires all parameters linked in the solution are known for describing temperature profiles over time. From this, using temperature profiles, it is possible to determine the thermo-physical parameters of the heating product.