A Brief Analysis of the Vessel 's Ventilation
Cottage ventilation is divided into natural ventilation and auxiliary mechanical ventilation, for the hot and humid climate of the hot and humid areas, relying solely on natural ventilation is obviously inadequate. Therefore, the choice of auxiliary mechanical ventilation becomes a necessity. However, whether it is natural ventilation or mechanical ventilation, are inseparable from the details of the control. Today we are talking about the details of the bacon from this thing.
The ventilation rate of the barn depends on the ventilation capacity of the fan, but the uniformity of the airflow distribution depends on the inlet position, the design and the regulator. The wind speed (244-305 m / min) of the air inlet can be increased by designing the size of the air inlet and adjusting the size of the opening without depending on the change in the ventilation rate (without changing the number of fans running). The size of the air intake can be adjusted by manual or automated.
Only the air inlet is set up reasonable, homes inside the door, windows and air leakage to ensure that the case of closed, it can make the fan to form the required negative pressure. The fresh air passing through the airtight vent to the inside reduces the amount of air entering the house through the designed air inlet and disrupts the airflow distribution. So the cattle to pay attention to the situation of the air leakage.
Open doors, windows and hay slopes. Too much air from a place to enter, making other areas of poor ventilation.
Wall, roof and the gap around the windows and doors. Even a small opening will interfere with the formation of good airflow, especially in the case of lower ventilation rates in winter.
Connected to the outside or in the two poultry houses between the flush or scraper slot openings. Use a movable door or a heavier curtain to block these large openings.
About the air inlet
The inlet of the negative pressure system, for example, consists of continuous trough, box and square inlets. Common continuous troughs have a regulating plate with adjustable opening size. The size of the air inlet is adjusted by the adjustment plate so that the air flow velocity can be increased and the mixing of the air flow can be improved. Rigid adjustment plates can not be bent, which can cause uneven distribution of airflow. The ceiling near the inlet made of a more smooth surface, which can make the air flow is not disturbed. To ensure that the screw conveyor, fluorescent, pipe and ditch equidistant inlet at least 1.8 meters. When ribbed ceilings are used, the east side of the ribs is parallel to the direction of the airflow. If the ribs must be installed vertically with the airflow, then the ceiling is required to have a smooth surface, lined up at least 45 cm from the inlet.
Under low pressure conditions, continuous trough inlet is difficult to control at lower wind speeds. When the airflow is low, the intermittent intermittent air inlet can improve the distribution of airflow. Low wind speed will lead to confusion in the distribution of air, resulting in air flow will harm young calves. The air conditioning system can replace or provide a continuous trough inlet in the calf. The continuous trough inlet is used in lactating cows because of the high ventilation rate in winter here.
The following points should be considered when selecting and determining the slot inlet position:
The barn span. For a 12-meter-wide livestock and poultry house, a continuous trough inlet is required to be placed on the ceiling along the sides. For larger livestock and poultry houses, add one or more trough or box air in the ceiling.
The longest distance. The maximum distance between the fan and the air inlet is about 23 meters.
Cold weather conditions of the air inlet. The roof space (the space between the ceiling and the roof) can be used as a wind inlet for wind protection. The wind of the air inlet comes from the roof space or the house.
Intake system. Ensure that the (outer) air intake system provides sufficient fresh air for the air intake. For example, for trough air vents, it is necessary to ventilate during the winter and warm seasons, ensuring that the openings in the eaves and walls are 1.5 times the maximum trough area required for the warmer season.
Hot weather conditions of the air inlet. Get fresh air directly from the outside. Roofs use insulation to reduce solar radiation and get fresh air from the roof space. Outside the air at the end of the gable or the eaves of the screen openings into, and then through the thermal insulation duct into the house.
About inlet control
Reasonable inlet control is critical for good ventilation. Under ideal conditions, the size of the air inlet varies with the change in ventilation rate (fan opening or closing or speed change). It is recommended to use automatic control inlet size. Manual control requires periodic adjustments. It is convenient to adjust the baffle by turning the winch and the rope system during manual operation adjustment. Install a dynamometer near the winch, which allows for more precise control of the baffle. The manual control of the baffle should be adjusted according to the weather forecast.
In the control of precision, the slot air inlet can be automatically adjusted to adjust the curtain than the rigid baffle. At low ventilation rates, the wind speed at the entrance is low and will cause the cold air to sink. Shading and frosting and frost on the ceiling are also a problem. Plastic curtains use a certain number of years after its elasticity is reduced, so at least one year to check once, if necessary, timely replacement.