Cooling method of the glass greenhouse
1, shade cooling: is the use of opaque or light transmittance low material shading down light, prevent excess solar radiance into the greenhouse, both crops can grow normally, and reduce the temperature of the greenhouse. Due to the difference in shading materials and installation methods, the greenhouse temperature can generally be reduced by 3℃ ~ 10℃. Shading methods include indoor shading and outdoor shading. An indoor shading system is a supporting system made of pulling metal wire or plastic network cable on the glass greenhouse skeleton, and the shading net is installed on the supporting film line. Generally using electric control or manual control.
An outdoor shading system is installed in the greenhouse outside the skeleton of a shade frame, the shade net is installed on the skeleton, and the shade net can be used to pull the curtain mechanism or roll film mechanism, free to open and close. Outdoor installation of sunshade net cooling effect is good, can directly block the solar energy outside the greenhouse, all types of sunshade net can be used.
2. Evaporation and cooling: evaporation and cooling are to use the unsaturation of air and the latent heat of evaporation of water in the glass greenhouse to cool down. When the moisture contained in the air does not reach saturation, water will evaporate into water vapor the air, water evaporation at the same time absorbs the heat in the air, reduce the temperature of the air, and improve the air humidity. In the process of evaporation and cooling, the air inside and outside the glass greenhouse must flow, the high temperature and high humidity gas in the greenhouse are discharged from the greenhouse, and fresh air is added, so the method of forced ventilation must be adopted. At present, the methods of evaporation cooling include wet curtains, fan cooling, and spray cooling.