Evaluation of the microclimate in a traditional colombian greenhouse used for cut flower production

Abstract

Cut flower production in the Bogotá savanna is one of Colombia’s main export products. Flower production is mainly carried out in greenhouses, as this type of production system has substantial advantages over crops grown in open fields. Protected agriculture provides timely climate management that improves crop yields. The objective of this work was to build and validate a 3D CFD numerical model to understand the spatial distribution of temperatures because of the air flow dynamics inside a typical greenhouse in the Bogotá savanna. Root mean square error (RMSE) and mean absolute percentage error (MAPE) were the statistical indicators used between experimental and simulated wind speed and temperature data. The simulations considered twelve evaluation scenarios that were established based on the climatic conditions characteristic of the study region. The results indicate that under regional conditions of temperature and wind for this type of passive greenhouse, there is a deficient ventilation rate. This rate does not exceed 35 exchanges h−1 compared to the recommended rates for crops, which is between 45 and 60 air exchanges h−1 . This renewal rate contributes to the heterogeneity of the microclimatic dynamics of the greenhouse, presenting hot spots with temperature values above 32◦C in all examined scenarios. For the lower air speed scenarios (<1 ms−1 ), these areas of high temperature can reach up to 50% of the cultivated area. Therefore, it is suggested that future studies should seek technical solutions to optimize the microclimatic conditions of the greenhouse design used in the Colombian floriculture sector.