Ventilación natural en invernadero con mallas anti-insecto evaluadas con un modelo computacional de fluidos

Abstract

Introducción. En Colombia, la producción hortícola en el trópico bajo es limitada principalmente por factores bióticos como el ataque de plagas, patógenos y factores abióticos como valores extremos de temperatura, radiación solar, viento y precipitación. Objetivo. Evaluar dos tipos de mallas anti-insecto en las áreas de ventilación de un invernadero colombiano ventilado de formado natural con el fin de analizar el efecto sobre las tasas de ventilación y el microclima generado. Materiales y métodos. El Estudio se desarrolló en el año 2019 en el departamento de Magdalena, Colombia. El enfoque metodológico incluyó el uso de modelo computacional de fluidos (CFD) 2-D para el desarrollo de quince simulaciones en estado estacionario, el modelo CFD fue validado experimentalmente en el prototipo del invernadero real evaluado. Resultados. Los parámetros de bondad de ajuste entre los datos medidos y simulados mostraron valores de error medio absoluto (MAE) y la raíz del error cuadrático medio (RMSE) para la temperatura y la humedad relativa de 0,15 y 0,32 °C, 2,41 y 2,73 %, respectivamente. Hubo una reducción promedio de las tasas de ventilación entre 55,3 y 77,1 % en comparación con el escenario de referencia que no incluyó la presencia de mallas anti-insecto, esta reducción generó modificaciones en el comportamiento de las variables temperatura y humedad relativa en el interior del invernadero, con una marcada distribución espacial heterogénea. Conclusión. Las condiciones micro climáticas más inadecuadas se presentaron en escenarios de baja velocidad de viento exterior, por lo tanto, es recomendable seleccionar e implementar algún tipo de malla anti-insecto en las áreas de ventilación de un invernadero basado en el comportamiento local de esta variable.

Research on the Microclimate of Protected Agriculture Structures Using Numerical Simulation Tools: A Technical and Bibliometric Analysis as a Contribution to the Sustainability of Under-Cover Cropping in Tropical and Subtropical Countries

“…Goodness-of-fit 34 [5,15,17,19,32,37,47 Statistical analysis and goodness-of-fit 3 [6,154,156] Another form of quantitative analysis identified in 15 studies was the construction of trend graphs between measured and simulated data and the application of statistical tests to analyze these datasets. In general terms, these statistical tests with 95% confidence intervals sought to determine whether there were significant differences between the variances or between each of the measured and simulated datasets and, based on these results, to accept or reject the validity of the CFD model [11,175].…”

“…Microclimatic evaluation is the type of validation that allows recording the behavior of the microclimate inside the structure and its interaction with the plants and the climatic conditions outside. The climatic variables inside protected agricultural structures with which CFD models are validated have usually been temperature and relative humidity in most studies [5,47,79,104]. As a second line of use for validation, variables such as air flow velocity and direction have been quantified [15,29]; other studies have investigated the measurement of the CO 2 concentration [19,150], heat flow from the ground [152], and the radiation level [181].…”

“…It should also be mentioned that the more these goodness-of-fit measures tend to 0, the better the predictive quality of the implemented CFD model [29]. Within this group of studies, it is worth highlighting those that achieved RMSE values below 0.7 • C for temperature [83,102,143] and below 4% for relative humidity [47,166].…”

“…This is reflected in the number of studies that have been developed related to this topic [17,[41][42][43]. Within these studies, we have also found research where the objective was the study of anti-insect screen establishment in the ventilation areas of passive greenhouses and their effect on natural ventilation [44][45][46][47]. There have also been more recent studies evaluating the microclimate and its variation due to the presence of different types of crops and at different phenological stages or the effect on the microclimate due to the implementation of active climate control equipment, such as heating, cooling, and CO 2 injection systems [48][49][50][51][52].…”

Contribution to the Sustainability of Agricultural Production in Greenhouses Built on Slope Soils: A Numerical Study of the Microclimatic Behavior of a Typical Colombian Structure

“…The CFD study has allowed the study of almost all existing passive greenhouse models worldwide, and has also been implemented as a tool for the optimization of climate management in greenhouses with active climate control [18][19][20]. There are currently a considerable number of studies applied to agricultural investors that have used CFD simulation to analyze thermal distribution [10,21,22], moisture distribution [5,21,23], efficiency of heating systems [24][25][26], the operation of cooling systems [27][28][29] and the microclimate generated as a function of different ventilation configurations [7,12,[30][31][32]. In the specific case of Colombia, the use of CFD and other modelling techniques to determine the behavior of the main greenhouse structures used has been carried out for the specific conditions of the Bogotá savannah and for a topography of flat soils, which is where the ornamental and cut flower industry is generally developed [33][34][35].…”