Views: 2023 Author: LONGMU Publish Time: 2023-06-08 Origin: LONGMU
In summer, relying solely on the ventilation system in the chicken house can no longer meet the cooling needs. As an efficient and environmentally friendly cooling method, the wet curtain is widely used in livestock and poultry farming. However, in the use of wet curtains, many farmers and friends have some misunderstandings, and preparations need to be made before the wet curtains are opened. How to use the wet curtain? These questions plague many chicken farmers. In this article, we will answer them in detail.
Common misunderstandings in the use of cooling pad
(1) Myth: The lower the water temperature, the more obvious the cooling effect
Many farmers think that the lower the water temperature of the wet curtain, the more obvious the cooling effect. This view has obvious mistakes. The cooling principle of the wet curtain is "water evaporates and absorbs heat". Under the action of gravity, water flows from top to bottom, forming a water film on the surface of the corrugated fiber of the cooling pad. When the fast-flowing air passes through the wet curtain, the water in the film Water will absorb the heat in the air and then evaporate. The evaporation of water will take away a lot of heat to reduce the temperature of the air passing through the wet curtain, so as to achieve the purpose of cooling. The evaporation of water is directly related to the water temperature, so in fact, the higher the water temperature, the higher the temperature. Evaporation intensifies, and the water takes away more heat. Therefore, when the cooling pad cools down in summer, normal-temperature water can achieve a good cooling effect.
(2) Myth:The wetter the cooling pad, the more obvious the cooling effect
When the cooling pad cools down, under the action of the water pump and gravity, the water forms a wrinkled water film on the corrugated fiber surface of the cooling pad from top to bottom with a total area equivalent to 10 times the appearance area of the cooling pad, which can ensure the air and water The largest contact area of the membrane can achieve the best cooling effect. Therefore, if the cooling pad is too wet, it will cause long-running water to block the pores of the cooling pad, reducing the contact area between the cooling pad and air, and resulting in a decrease in the cooling effect.
(3) Myth:The wet curtain is used with the ventilation window, the temperature is more uniform and stable
Under negative pressure ventilation, an "air pressure difference" will be formed in the chicken house, and the outdoor air will quickly detour through the cooling curtain and collide with the water film of the cooling curtain to quickly achieve the effect of cooling. If the ventilation window is opened and the "air pressure difference" does not meet the requirements, the effect of the water film colliding with the air will decrease, and the cooling effect of the wet curtain will decrease. Therefore, if the ventilation window and the wet curtain are used at the same time, it will easily lead to insufficient "air pressure difference" in the chicken house, which will affect the cooling effect.
(4) Myth:The faster the wet curtain cools down, the better
Although the purpose of using the cooling pad is to cool down, the faster the cooling is not the better, the cooling of the cooling pad too fast will cause the temperature in the chicken house to drop sharply, and the chickens cannot adapt, especially the chickens near the cooling pad will catch a cold The probability of such symptoms is extremely high, resulting in cold stress, so when cooling the wet curtain, it should be done step by step and wetted step by step. With the traditional wet curtain cooling system, the house temperature drops rapidly after it is turned on, and the chickens have a high risk of catching a cold.
The premise using the cooling pad, in my opinion, there are several premises:
1. The temperature of the outside environment is higher than the required temperature of the chicken house, and the temperature of the chicken house is still rising when the maximum wind speed adapted to the chickens is reached by increasing the ventilation.
2. The humidity in the chicken house is between 50-65.
3. When the chickens have adapted to the current wind speed, they are still very hot.
The above three conditions are indispensable, blindly opening the water curtain and improper operation may cause adverse consequences.
In this case, water curtains are not recommended:
In cloudy and rainy weather, the external humidity reaches 100%, and the moisture in the water curtain evaporates slowly; for water vapor entering the chicken house, the humidity in the chicken house is too high. Heat stress index = 1.8 * temperature + 32 + relative humidity value to 155 is the critical value.
Wet curtain use skills
In the use of cooling pad, we need to master the following tips to achieve twice the result with half the effort.
① The cooperation between the wet curtain and the fan mainly depends on the external ambient temperature, the age of the chicken, the target temperature and the air cooling effect, etc.;
② When the wet curtain is just opened and used, follow the principle of step-by-step and adapt to the process of chicken flocks, so that the wet curtain is always in a state of gradual drying and wetting, so as to achieve the best effect of water vapor evaporating from the surface of the wet curtain paper;
③ When opening the wet curtain for the first time, some fans should be turned off first to reduce the wind speed over the curtain and the surface wind speed of the wet curtain, so as to avoid the stress of the chickens caused by the sudden drop in temperature;
④ The cooling temperature of the wet curtain is set to be 0.5-1.5°C higher than the opening temperature of the last longitudinal fan;
⑤ A wind deflector must be installed to prevent the wet and cold air from blowing directly to the chickens near the wet curtain;
⑥ After using the wet curtain, it is best to maintain the range of negative pressure in the house at 1.27-2.54mm water column;
⑦ When using the wet curtain, you must pay attention to the external humidity. When the external humidity is above 80%, you need to stop using the wet curtain, increase the number of fans, etc., and increase the surface wind speed of the chickens in the house to avoid chicken heatstroke;
⑧ The chicken coop maintains a good airtight performance;
⑨ The circulating water storage tank should be covered and sealed, and the water should be replenished regularly and quantitatively every day to keep the water quality clean and fresh, free of weeds and small animal corpses, etc.;
⑩ Regular maintenance of water pumps, wet curtains, etc., prepare a large number of spare water pumps, power generation diesel oil, etc. in advance. When the wet curtain is not in use, it is airtight, dry, clean and hygienic. Water is strictly prohibited to prevent chickens from getting cold.
In short, the cooling and heatstroke prevention of chicken coops in summer is the top priority of all management. Wet curtains are more and more widely used in the management of modern chicken coops. Thinking, mastering the skills of using the wet curtain, to ensure nothing goes wrong.