Computational Model With Topological and Multidimensional Thermal Stress Analysis of a Natural Convection Dryer

Abstract

Abstract. The biomass-based dryer of agricultural produce is a reliable and consistent drying solution for regions with abundant rainfall to reduce postharvest losses. It is known that the performance of dryers varies depending on the use of energy storage materials and associated thermal profiles. This article proposes the design of a biomass-fueled natural convection dryer and the thermal stress analysis of its structures based on the space–time geometry considering multidimensional temperature fields. We present the computational analysis of the thermal profiles of the dryer integrating the energy storage materials. The experiments are conducted under different conditions, such as (a) without thermal storage materials, (b) using paraffin wax or pebbles as energy storage materials, and (c) using both the energy storage materials in a mix. Results indicate that combining thermal storage materials yields maximum heat retention, maintaining higher temperatures for a longer time duration. Thermal stress analysis confirms that all dryer components remain structurally safe under operating temperatures, with manageable thermal stresses and adequate allowances for expansion ensuring stable and reliable performance. Furthermore, we present the topological analysis of heat distribution profiles of drying trays placed in the drying chamber providing analytical insights. The analytically predicted thermal stresses were validated using comsol thermo-mechanical von Mises stress simulations, showing strong agreement with deviations within 1.8–4.9% for key dryer components. We show that there is interplay between various uniformities of thermal profiles and the topological formulations exposing several interesting properties, which would lead to the improved design for better utilization of available thermal energy in the drying chamber.