{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:05:32Z","timestamp":1760234732791,"version":"build-2065373602"},"reference-count":40,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2021,6,9]],"date-time":"2021-06-09T00:00:00Z","timestamp":1623196800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Energies"],"abstract":"<jats:p>Commonly based on the liquid diffusion theory, drying theoretical studies in porous materials has been directed to plate, cylinder, and sphere, and few works are applied to non-conventional geometries. In this sense, this work aims to study, theoretically, the drying of solids with oblate spheroidal geometry based on the thermodynamics of irreversible processes. Mathematical modeling is proposed to describe, simultaneously, the heat and mass transfer (liquid and vapor) during the drying process, considering the variability of the transport coefficients and the convective boundary conditions on the solid surface, with particular reference to convective drying of lentil grains at low temperature and moderate air relative humidity. All the governing equations were written in the oblate spheroidal coordinates system and solved numerically using the finite-volume technique and the iterative Gauss\u2013Seidel method. Numerical results of moisture content, temperature, liquid, vapor, and heat fluxes during the drying process were obtained, analyzed, and compared with experimental data, with a suitable agreement. It was observed that the areas near the focal point of the lentil grain dry and heat up faster; consequently, these areas are more susceptible to the appearance of cracks that can compromise the quality of the product. In addition, it was found that the vapor flux was predominant during the drying process when compared to the liquid flux.<\/jats:p>","DOI":"10.3390\/en14123405","type":"journal-article","created":{"date-parts":[[2021,6,9]],"date-time":"2021-06-09T14:16:04Z","timestamp":1623248164000},"page":"3405","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Non-Equilibrium Thermodynamics-Based Convective Drying Model Applied to Oblate Spheroidal Porous Bodies: A Finite-Volume Analysis"],"prefix":"10.3390","volume":"14","author":[{"given":"Jo\u00e3o C. S.","family":"Melo","sequence":"first","affiliation":[{"name":"Federal Institute of Education, Science and Technology of Rio Grande do Norte, Caic\u00f3 59300-000, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1026-4523","authenticated-orcid":false,"given":"Jo\u00e3o M. P. Q.","family":"Delgado","sequence":"additional","affiliation":[{"name":"CONSTRUCT-LFC, Department of Civil Engineering, Faculty of Engineering, University of Porto, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5841-6023","authenticated-orcid":false,"given":"Wilton P.","family":"Silva","sequence":"additional","affiliation":[{"name":"Department of Physics, Federal University of Campina Grande, Campina Grande 58429-900, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1691-1872","authenticated-orcid":false,"given":"Antonio Gilson","family":"B. Lima","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Federal University of Campina Grande, Campina Grande 58429-900, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4387-4600","authenticated-orcid":false,"given":"Ricardo S.","family":"Gomez","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Federal University of Campina Grande, Campina Grande 58429-900, Brazil"}]},{"given":"Josivanda P.","family":"Gomes","sequence":"additional","affiliation":[{"name":"Department of Agricultural Engineering, Federal University of Campina Grande, Campina Grande 58429-900, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6187-5826","authenticated-orcid":false,"given":"Rossana M. F.","family":"Figueir\u00eado","sequence":"additional","affiliation":[{"name":"Department of Agricultural Engineering, Federal University of Campina Grande, Campina Grande 58429-900, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6880-5951","authenticated-orcid":false,"given":"Alexandre J. M.","family":"Queiroz","sequence":"additional","affiliation":[{"name":"Department of Agricultural Engineering, Federal University of Campina Grande, Campina Grande 58429-900, Brazil"}]},{"given":"Ivonete B.","family":"Santos","sequence":"additional","affiliation":[{"name":"Department of Physics, State University of Paraiba, Campina Grande 58429-500, Brazil"}]},{"given":"Maria C. N.","family":"Machado","sequence":"additional","affiliation":[{"name":"Department of Chemical, State University of Paraiba, Campina Grande 58429-500, Brazil"}]},{"given":"Wanderson M. P. B.","family":"Lima","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Federal University of Campina Grande, Campina Grande 58429-900, Brazil"}]},{"given":"Jo\u00e3o E. F.","family":"Carmo","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Federal University of Campina Grande, Campina Grande 58429-900, Brazil"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,9]]},"reference":[{"key":"ref_1","first-page":"159","article-title":"Uncertainty in the determination of equilibrium moisture content of agricultural products","volume":"7","author":"Silva","year":"2005","journal-title":"Rev. Bras. Prod. Agroind. Gd. Espec."},{"key":"ref_2","unstructured":"Park, K.J., Antonio, G.C., Oliveira, R.A., and Park, K.J.B. (2006). Process selection and drying equipments. 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