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The indoor climate of a greenhouse provides the plants with favorable growing conditions that can result in faster growth and higher yields. Important parameters to control in a greenhouse are the temperature, the humidity, and the level of CO2 concentrations. In southern Europe, both heating and cooling are required to control the greenhouse temperatures throughout the year. In this study, Computational Fluid Dynamics (CFD) simulations is employed to study the fluid flow through air distribution hoses (ADHs) in a research greenhouse in Bucharest, Romania. The ADHs are part of a novel, energy-efficient concept at the greenhouse, comprised of an integrated heat pump system, air handling units (AHUs), a dry cooler, and borehole thermal energy storage. The heat pump system provides both heating and cooling, while the greenhouse humidity is controlled by the AHUs. CO2-enrichment to the greenhouse is provided from installed CO2 tanks. The CO2-enriched air is circulated from the AHUs to the ADHs, which have a series of perforated holes along their lengths. In these preliminary simulations, different configurations of the perforated holes are simulated to optimize the mixing of the climate-controlled air with the greenhouse air. Both the diameters of the holes and the opening of the ADH outlet are varied to study the mass flow rates out of the holes. The CFD simulations provide suitable design criteria for the installation of ADHs in a greenhouse environment and for optimizing the efficiency of ADHs. [ABSTRACT FROM AUTHOR]

Apple is one of the most important fruit species in the Northern hemisphere. As apple production is seasonal, the disparities between production and consumption may be balanced by storing the fruits with or without controlled atmosphere. By this, locally produced apples are kept fresh, in good condition, until the next production season. Pathogens may cause considerable losses during storage, quantitative and qualitative, both by degrading the appearance and fruits taste and by producing mycotoxins, a major food safety issue that becomes increasingly important for the consumer. Qualitative depreciation is a normal process during storage, but the level of degradation depends on storage conditions. Cold stored fruits (1°C, 90% humidity) produced in two Romanian organic orchards were analyzed in 2019, four months after harvest. No postharvest treatment was applied. Our results showed that postharvest diseases were predominantly caused by fungal pathogens and that both latent infections originating from the field (Gloeosporium sp.) and wounds infections (Penicillium sp., Fusarium sp.) were damaging the fruits. [ABSTRACT FROM AUTHOR]