Thermodynamic evaluation of a greenhouse using computational fluid dynamics
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| Autores: | , |
|---|---|
| Format: | artículo original |
| Status: | Versión publicada |
| Fecha de Publicación: | 2025 |
| Beskrivelse: | Introduction. Computational Fluid Dynamics (CFD) is a technique for simulating the behavior of thermodynamic parameters. Objective. Evaluate the thermodynamics of a greenhouse using CFD, in order to propose improvements in lettuce production. Materials and Methods. The research was conducted between October 2022 and February 2023 at the Los Diamantes Agricultural Innovation Center, Limón, Costa Rica. The yield of three lettuce cycles was collected. A 3D mechanical model of the greenhouse was developed. A mesh of 482,664 elements was generated with refinement in the interior. The analysis was performed under steady-state flow, using the Navier-Stokes equation with the k-ε turbulence model and species transport with thermal interactions using the energy equation. Fluid materials (air and air-vapor mixture), solids (soil and polyethylene), and the crop as a porous medium were modeled. Evapotranspiration was estimated using meteorological data and crop coefficients. Boundary conditions included variable velocity input, constant temperature walls, and porous surfaces calibrated with bibliographic data. The model was validated using MAE and RMSE with errors less than 10%, and passive and structural improvements were proposed to optimize the internal microclimate of the greenhouse. Results. During the day, the average temperature and relative humidity in the greenhouse exceeded 30 °C and 65%, respectively, while during the night they decreased to 18 °C and close to 90 %. The temperature showed significant variations in the vertical axis, but remained more homogeneous longitudinally, while the relative humidity showed greater variability in both directions. Conclusion. The modeling allowed visualization of the greenhouse behavior, and it was proposed to increase the dimensions of the zenith window from 11 m² to 20 m²; the installation of two air recirculators and a mobile shade with 50% light transmissibility. |
| País: | Portal de Revistas UCR |
| Institution: | Universidad de Costa Rica |
| Repositorio: | Portal de Revistas UCR |
| Sprog: | Español |
| OAI Identifier: | oai:portal.revistas.ucr.ac.cr:article/1127 |
| Online adgang: | https://revistas.ucr.ac.cr/index.php/ragromeso/article/view/1127 |
| Palabra clave: | Equilibrio dinámico Producción de invernadero Modelación de cultivos Análisis térmico Thermodynamic equilibrium Greenhouse production Crop modelling Thermal analysis |