Fan wet curtain is an important function of modern greenhouse
The fan water curtain uses water curtain evaporation to cool down, and is widely used in agriculture and animal husbandry in China. It has the advantages of environmental protection, significant effects, and economic reliability. Water curtain (wet curtain) is a special paper honeycomb structural material, whose working principle is the natural physical phenomenon of “water evaporation and absorption of heat”, that is, water flows from top to bottom under the action of gravity, forming a water film on the corrugated fiber surface of the water curtain (wet curtain). When flowing air passes through the water curtain (wet curtain), the water in the water film will evaporate and absorb heat in the air, taking away a large amount of latent heat, Reduce the humidity of the air passing through the water curtain (wet curtain) to achieve the purpose of cooling. The cooling process of the wet curtain cooling system is completed within its core, the paper pad. There is a thin layer of water film on the corrugated fiber paper surface. When outdoor dry and hot air is sucked through the paper pad by the fan, the water on the water film will absorb the heat in the air and then evaporate into water vapor, so that the cool and moist air after treatment enters the room.
This natural process is like the wind blowing over the water. The temperature that a wet curtain can reduce depends on the difference between the dry and wet bulb temperature of the air and the efficiency of the wet curtain at this time. The value of cooling is the product of the two. Stable operation of the wet curtain cooling efficiency is usually constant. It can be seen that the hotter the weather, the better the cooling effect of the wet curtain. The pressure exhaust fan discharges air outward, causing the indoor air pressure to decrease, thinning the indoor air, forming a negative pressure zone. Due to the pressure difference, the air will compensate for entering the room, forming a canyon airflow zone of one inlet and one outlet.
In practical applications, negative pressure fans are installed centrally on one side of the greenhouse. Through specific engineering design, the air exchange speed and wind speed are designed according to needs. Any high heat, harmful gases, dust and smoke can be quickly discharged from the greenhouse, and any poor ventilation problems can be solved. Within a few seconds of starting the fan, the negative pressure exhaust fan can exhaust the greenhouse. The doors and windows close to the negative pressure fan are closed, forcing air to flow into the greenhouse through compensation from the doors and windows on the air inlet side. The air flows into the workshop from the intake in an orderly manner, forming a canyon airflow zone. The negative pressure fan has a fast ventilation rate of up to 99%.
Inspection before use (1) Check the operation of the fan motor and water pump. (2) The water level and quality of the wet curtain pool, and whether there are impurities in the filter.
Precautions during use (1) Start the fans one by one according to the grouping to avoid causing current overload. (2) Turn on the water pump and observe whether the water curtain is properly filled with water. (3) Adjust the front end switch of the wet curtain filter according to the water flow situation, control the water flow size, and require the water flow to flow evenly and slowly downward. (4) Adjust the lower and upper temperature limits of the thermostat, and the fan water curtain will automatically start and stop, saving energy and increasing the fan duration. (5) Monitor the water storage condition of the wet curtain pool at any time, and pay attention to adding water when it is less than 1/3. (6) When opening the fan water curtain, pay attention to closing the doors and windows of the greenhouse.
Precautions after Use Wet Curtain – During daily use of the fan system, attention should be paid to stopping the water pump for 30 minutes before shutting down the fan and drying the wet curtain; After the wet curtain stops running, check whether the accumulated water in the water tank is drained to avoid long-term immersion of the bottom of the wet curtain in water.
Subsequent maintenance items (1) Clean the wet curtain pool at least once a week. (2) The water in the wet curtain pool should be changed at least once a week to prevent the growth of green moss, etc. (3) Clean the wet curtain filter weekly. If the water quality suddenly deteriorates, clean the filter the same day after the water quality improves. (4) It is strictly prohibited to place objects around the wet curtain to avoid damage to the wet curtain. (5) A cover plate must be added above the wet curtain pool to prevent contamination by debris such as feed bags. (6) Do not add drugs containing bromine or chlorine to the water to avoid damaging the water curtain. You can add non corrosive disinfectants such as “bactericidal” to the water. (7) Green moss grows on the wet curtain, and can be removed by using a chemical crystal (trichloroisohydrouric acid), placing 5 grams per ton of water, and circulating for about 24 hours.
