Thermal convection coefficient in cooling process of lime fruit: Study through the Galerkin finite element method

Abstract

AbstractCooling is applied to horticultural products to reduce exposition time to inappropriate temperatures. In the present work, a mathematical model was proposed to describe the cooling behavior of lime fruit and to determine the thermal convection coefficient (h) involved. The Galerkin finite element method was used to obtain a numerical solution of the model and results were evaluated by comparing with experimental information. The coefficient h was dependent on fruit position in the cooling system, varied between 3.7 and 100.6 W/m2 °C with air velocity, and results corresponding to forced air were expressed in terms of Nusselt and Reynolds numbers.Practical ApplicationsA methodology was developed to determine the thermal convection coefficient (h) in the cooling process of a horticultural product. The procedure was based on fundamental heat transfer laws that were analyzed through the finite element method; however, it was step by step described and was programmed in the Matlab environment, which allows an easy application to other process conditions.