the method of cooling the glass greenhouse in summer In most parts of our country, the summer is hot and the temperature is high. When the outdoor temperature is above 30 ℃, the internal temperature of the greenhouse exceeds this 40 ℃. If only relying on ventilation, the temperature in the greenhouse is still above 35 ℃, normal production cannot be carried out in the greenhouse, and other cooling methods must be used to reduce the indoor temperature.
The main greenhouse cooling methods used in daily production are: 1. Shading and cooling is to use materials with opaque or low light transmittance to shade and reduce light to prevent excess solar radiation from entering the greenhouse, which not only ensures that crops can grow normally, but also Lower the temperature of the greenhouse. Due to the difference in shading materials and installation methods, the greenhouse temperature can generally be reduced by 3°C to 10°C. Shading methods include indoor shading and outdoor shading. The indoor shading system is a support system made by pulling and connecting metal wires or plastic mesh wires in the greenhouse frame, and installing the shading net on the supporting film line. Generally, electric control or manual control is used. The outdoor shading system is to install a shading skeleton outside the greenhouse skeleton, and install the shading net on the skeleton. The outdoor installation of the sunshade net has a good cooling effect, and can directly block the solar energy outside the greenhouse. Various types of sunshade nets can be used.
2. Evaporative cooling Evaporative cooling is to use the unsaturation of air and the latent heat of evaporation of water to cool down. When the water content in the air is not saturated, the water will evaporate into water vapor and enter the air. When the water evaporates, it absorbs the heat in the air, reduces the temperature of the air, and increases the air humidity. In the process of evaporative cooling, the air flow inside and outside the greenhouse must be ensured, the high temperature and high humidity gas in the greenhouse must be discharged from the greenhouse, and fresh air must be replenished. Therefore, forced ventilation must be adopted. At present, the methods of evaporative cooling include wet curtain - fan cooling and spray cooling.
3. The roof spray cooling system is to spray water evenly on the roof of the glass greenhouse to reduce the temperature of the greenhouse. When the water flows on the roof of the glass greenhouse, the water exchanges heat with the glass of the greenhouse roof, and takes away the heat in the greenhouse. In addition, when the thickness of the water film is greater than 0.2 mm, all the energy of solar radiation is absorbed and taken away by the water film. This is equivalent to shade. Related concepts Sun room Sun room is also called glass room,