For plant production, suitable environmental conditions should be provided in the greenhouse as well as in the winter. In order to provide suitable environmental conditions where plants can grow in summer, the greenhouse heated in winter should keep the internal temperature and humidity of the greenhouse within certain limits. Therefore, cultivation in the greenhouse in summer can be achieved by airing, cooling and shading the greenhouse.
When it comes to ventilation, the internal air of the greenhouse and the external atmospheric air are changed. Ventilation of greenhouses is not done only for the purpose of cooling the greenhouses and in the summer. Ventilation of greenhouses is done more in summer and less in winter and for different purposes.
In the greenhouse, ventilation is carried out in order to replace the greenhouse internal air, which is rich in oxygen and poor in carbon dioxide compared to the external atmosphere, with the outside air. Thus, the carbon dioxide that plants need for vegetative production enters the greenhouse. Ventilation is carried out in order to balance the temperature inside the greenhouse, that is, to exclude the high heat caused by excessive sunbathing, outside the greenhouse. Thus, the slowdown in crop production caused by high temperature has been eliminated and the indoor greenhouse temperature may be 1-2 ° C higher than the outdoor temperature. Balancing the proportional humidity in the greenhouse can be achieved by ventilation. Excess moisture in the greenhouse may cause some disease factors to occur in the plants and prevent the plants from sweating. Since the plant whose sweating ceases to receive water and nutrients from the soil, the production of vegetative material also stops.
We can list these features as follows:
The appropriate temperature of the air in the greenhouse is between 25-30 ° C according to the type of plant grown in the greenhouse. The temperature of the air in the greenhouse is at least 1 -2 ° C higher than the outside of the greenhouse. This temperature difference varies considerably according to the summer and winter months. As the temperature difference of the air inside and outside the greenhouse decreases, the desired ventilation cannot be made in the greenhouse. Greenhouse humidity is the second factor providing air movement in the greenhouse. As the humidity increases in the greenhouse, the air expands and moves upward. Dry air, on the other hand, replaces the rising humid air since it is heavier. The movement of a humid hot air is more than that of a dry hot air. Another factor causing air movement in the greenhouse is the wind. With the pressure and suction effects of the wind in the greenhouse, there is air movement in the greenhouse In the very windy regions, an air movement of 0.2 m / s is determined even when the windows are closed. It should be taken into consideration that this speed will increase depending on the wind speed in greenhouses with poor structure and protection. The height difference between the roof windows that allow the heated air to be thrown out and the side ventilation windows that allow the cold air to enter the hot air that goes out, depends on the height difference between the greenhouse side windows and the roof ridge. The ventilation speed increases as this difference, which is usually 3-4 m, increases.
The upper ventilation system works with a rack gear system. The opening arms made of 40 x 30 profiles with 2 m width along the ridge on both sides of the hill are in the form of a butterfly. The system is opened and closed by placing a rack and gear on the 34 x 2.5 mm pipe used as a shaft placed on specially made ball bearings and pushing the window of this system.
One motor will be used for each window and limit switches are above the motors. The rack gears to be used are 200cm long and are placed on the shaft with a rack gear every 2.5m.
The rack cassette hub gear is made of cast steel and highly abrasion resistant. 275 gr / m2 galvanized material is used as material.
Our fly net system, which will be installed together with the greenhouse cover or coating on the ventilation system in the greenhouse structure, protects the plants and products we grow from pests. It prevents chemical and spraying and prevents product and insect attack in the system. It increases product efficiency. Mesh and properties may change according to greenhouse properties and coating.