Influence of the Height in a Colombian Multi-Tunnel Greenhouse on Natural Ventilation and Thermal Behavior: Modeling Approach

Abstract

first_pagesettings Open AccessArticle Influence of the Height in a Colombian Multi-Tunnel Greenhouse on Natural Ventilation and Thermal Behavior: Modeling Approach by Edwin Villagrán 1,Jorge Flores-Velazquez 2,*ORCID,Mohammad Akrami 3,*ORCID andCarlos Bojacá 1ORCID 1 Department of Biological and Environmental Sciences, Faculty of Natural Sciences and Engineering, Jorge Tadeo Lozano University, Bogotá 111321, Colombia 2 Coordination of Hydrosciences, Postgraduate Collage, Carr Mex Tex km 36.5, Montecillo Edo de Mexico 62550, Mexico 3 Department of Engineering, University of Exeter, Exeter EX4 4QF, UK * Authors to whom correspondence should be addressed. Academic Editors: Muhammad Sultan, Yuguang Zhou, Walter Den and Uzair Sajjad Sustainability 2021, 13(24), 13631; https://doi.org/10.3390/su132413631 Received: 25 October 2021 / Revised: 25 November 2021 / Accepted: 6 December 2021 / Published: 9 December 2021 (This article belongs to the Special Issue Sustainable Agricultural Engineering Technologies and Applications) Download PDF Browse Figures Citation Export Abstract The dimensions of a passive greenhouse are one of the decisions made by producers or builders based on characteristics of the available land and the economic cost of building the structure per unit of covered area. In few cases, the design criteria are reviewed and the dimensions are established based on the type of crop and local climate conditions. One of the dimensions that is generally exposed to greater manipulation is the height above the gutter and the general height of the structure, since a greenhouse with a lower height has a lower economic cost. This has led some countries in the tropical region to build greenhouses that, due to their architectural characteristics, have inadequate microclimatic conditions for agricultural production. The objective of this study was to analyze the effect on air flows and thermal distribution generated by the increase of the height over gutter of a Colombian multi-tunnel greenhouse using a successfully two-dimensional computational fluid dynamics (CFD) model. The simulated numerical results showed that increasing the height of the greenhouse allows obtaining temperature reductions from 0.1 to 11.7 °C depending on the ventilation configuration used and the external wind speed. Likewise, it was identified that the combined side and roof ventilation configuration (RS) allows obtaining higher renovation indexes (RI) in values between 144 and 449% with respect to the side ventilation (S) and roof ventilation (R) configurations. Finally, the numerical results were successfully fitted within the surface regression models responses.