The greenhouse realizes continuous planting for 365 days, creating environmental conditions suitable for plant growth to a certain extent. At the same time, it also needs to be isolated from the influence of the external natural environment. For example, it is necessary to ensure indoor warmth in the cold winter and reduce the indoor temperature in the hot summer. Due to the thermal insulation and light transmittance of greenhouse buildings, special attention should be paid to the cooling of the greenhouse in summer.
The cooling of the greenhouse is a systematic greenhouse. We generally need to consider this situation when designing the greenhouse plan. Generally, the customer provides the climate and environmental conditions of the location of the greenhouse. When the customer cannot provide it, we design it based on the climate data of the customer's location.
Conventional cooling methods include: shading system cooling, window ventilation cooling, cooling pad& exhaust fan
Shading system cooling
Depending on the different shading materials used, it is divided into reflection cooling and absorption cooling. Aluminum foil sunshade net reflects part of the sunlight directly back to the atmosphere, reducing the amount of radiation entering the greenhouse (reflectivity can reach 30%-70%)
window ventilation cooling
Hot air with low density rises naturally and is discharged through the roof skylight, and cold air is supplemented from the side window/bottom window to form a convection cycle. When the skylight opening angle is ≥30°, the ventilation volume can reach 40-60 times/hour
Cooling pad and exhaust fan
Evaporation heat absorption and forced ventilation, when the liquid water on the surface of the water curtain evaporates, it absorbs the sensible heat in the air and lowers the air temperature. In theory, the air can be cooled to a temperature close to the water source temperature.
As global climate change intensifies, the cooling systems used in some greenhouses that have been built can no longer provide plants with more suitable greenhouse conditions. Or it is to reduce energy consumption. Customers can choose to add a mist cooling system. The water is pressurized and atomized into extremely fine particles of 10-50 microns through special nozzles, which directly absorb heat from the air. Each gram of water evaporates and absorbs 2260 joules of heat, directly reducing the sensible heat of the air, and cooling the air by discharging high-temperature and high-humidity gases through windows. At the same time, it is combined with a circulating fan to avoid excessive local humidity.
Advantages of mist cooling
1. The energy consumption is only 1/3 of the fan water curtain system and 1/10 of the air conditioner.
2. Save 30% of water and maintenance-free (no algae breeding problems)
3. Accurate temperature and humidity control, fluctuation within ±1℃
4. Reduce the temperature of the poultry house while suppressing dust
Post time: Apr-25-2025