Title: A global thermal node model for analysing the effect of glass cover geometric parameters for no-load indirect solar dryer

Authors: Ernest Léontin Lemoubou; Carine Pamela Aghogue Donchi; Hervé Thierry Tagne Kamdem; René Tchinda

Addresses: Life and Industrial Systems Thermal Engineering-Team (LISTE-T), Research Unit of Mechanics and Physical Systems Modeling (UR-2MSP), Department of Physics/Faculty of Sciences, University of Dschang, Dschang, Cameroon ' Life and Industrial Systems Thermal Engineering-Team (LISTE-T), Research Unit of Mechanics and Physical Systems Modeling (UR-2MSP), Department of Physics/Faculty of Sciences, University of Dschang, Dschang, Cameroon ' Life and Industrial Systems Thermal Engineering-Team (LISTE-T), Research Unit of Mechanics and Physical Systems Modeling (UR-2MSP), Department of Physics/Faculty of Sciences, University of Dschang, Dschang, Cameroon ' Institute of Technology Fotso-Victor Bandjoun, Bandjoun, Cameroon

Abstract: In this paper, a global thermal node model is developed for describing no-load indirect solar dryer with double-glass collector. The dryer is formed with drying unit and double air pass collector mounted with two absorber plates separated by confined air. The nodal model takes into account the time variations of solar flux, convection heat losses to the ambient and radiated flux from the soil surface. The mathematical model describing the transient heat transfer process is derived from the node theory, while the surface soil fluxes are approximated using the boundary layer similarity theory. The resulted equations are solved numerically using the iterative finite difference method. The results obtained indicate excellent agreement of the global node model proposed when compared predictions to experimental values of the literature. The simulation reveals significant effect of glass cover thickness and glass covers confined air thickness on the thermal behaviour of the dryer.

Keywords: global node model; indirect solar dryer; numerical simulation; glass cover geometric parameters; boundary layer theory; dynamic conditions; thermal behaviour.

DOI: 10.1504/IJESMS.2025.144884

International Journal of Engineering Systems Modelling and Simulation, 2025 Vol.16 No.2, pp.87 - 100

Accepted: 05 Dec 2023
Published online: 06 Mar 2025 *

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