Explanation of negative pressure application of breeding fans
Some time ago, I contacted the technical personnel of many foreign companies on the training of breeding and breeding fans, and also contacted several old technical field directors in Shandong. Most people are putting on cages, and I think this will not work.
The lecture teachers all mentioned the negative pressure of the breeding fan, and proposed that the negative pressure should be determined according to the width of the chicken house, and should be operated by a fixed value measured by foreigners. Prior to this, the negative pressure of our chickens was felt by hand. Pure experience. Because experience is sometimes unreliable, the breeding effect is also very unstable. If I remember correctly, the 15 m wide chicken coop seems to have a theoretical negative pressure of 20 pa.
In practical operation, this value does not work at all, because cage culture is not the same as net culture. It either comes in or is ventilated. It needs negative pressure to give the wind a force, and then it circulates in the chicken house under the action of air flow. . Each group of dampers is a small circulation system, and then the small circulation system forms a large circulation system and is discharged from the back. This is an effective ventilation mode (single transitional ventilation). I think that the negative pressure of ventilation in cages should change with the purpose of ventilation. For example, when chicks are brooding, we have fewer fans. The purpose of ventilation is just to change the air. At this time, our negative pressure should be Smaller, but because of the obstruction of the cage, the negative pressure is naturally slightly larger than the theoretical value.
In the later period, most of our ventilation (especially in summer), in addition to ventilation, should also reduce the somatosensory temperature. At this time, we should increase the negative pressure of the breeding fan to make the wind speed faster.