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Industrial Climate ControlThe primary purpose of the Climate Control Air Curtain is to prevent the influx of outside air through an opening in to heated or cooled area. Opening where an Air Curtain would typically be used are exterior shipping and receiving doors to plants and warehouses and interior doors between plant areas of different temperatures. (these applications are discussed in further detail below). In addition there are special applications such as the control of oven temperature, humidity and dust or the control of the fresh air . Other applications not discussed here are preventing the drifting of over spray from spray paint booths; blowing water off of hot steel after it has been dipped; and blowing scrap paper from a paper cutter into a collecting intake. In order to control climate an Air Curtain emits an air stream with enough velocity at the nozzle and the width of the nozzle. For different door sizes and different wind conditions , different air velocities at the nozzle are required. To prevent the entry of outside winds the discharge nozzle is angled outward so that the air leaving it meets the wind trying to enter. The wind will meet or strike the Air Curtain stream in the doorway. This working principle is shown in the figure below: When the vector representing the air stream and the vector representing the wind equalize they form a resultant which should meet the floor in the door plane for maximum efficiency. In many buildings with high ceilings the air tends to stratify into a warmer layer at the ceiling and a considerably cooler one at the floor. For such buildings it is recommended that the air curtain be mounted across the top of the doorway opening and that it be provided with a top intake connected to a duct extending up to the ceiling. (as illustrated):
The warm air will then be drawn down into the Air Curtain and blown to the floor putting otherwise wasted heat to use. This warmer air also helps to reduce the wind chill of the moving air. Air Conditioned Areas![]() Air conditioned areas are normally well balanced and seldom have negative pressure. In
fact a slight over-pressure is more common where air conditioning systems are bringing
fresh air into an area. Industrial Oven Openings![]() Using Air Curtains on opening to ovens has resulted in fuel savings of up to 40% of the total oven fuel consumption. Air Curtains are normally installed horizontally over the oven opening and angled slightly inward toward the oven to contain the hot air that is trying to come out at the top. Many Air Curtains are successfully operating on ovens with temperatures up to 475° F. The Air Curtain drive motor should be located to the side of the oven opening to protect them from damage from hot air that would escape in the even of a shutdown of the Air Curtain. Oven applications should be designed case by case to meet each set of unique conditions. Dust and Humidity Control![]() Air Curtains should be installed on the clean or humidity controlled side of the opening, blowing toward the dirty or uncontrolled side. This will prevent the influx of the dust particles or atmospheric vapour. Air Curtain units for dust and humidity control are approximately 70% efficient. The 30% inefficiency is caused by particles are air becoming entrained in the Air Curtain stream and working their way through. Mines
Air Curtains are in use in a hard rock mine at the 1100 foot depth to control the flow of fresh air that is introduced into the mine. Installed at several points along the main airway the Air Curtain deflects some of the fresh air flow out into the shafts. For more detailed information on this very successful application please contact the factory. Commercial Entrances
Commercial Entrance Air Curtains are becoming widely used in building entrances to
reduce energy consumption and provide comfort. In winter they retain warm inside air and
prevent the influx of cold air. They can also supply additional heat in the door area
using optional electrical, steam or hot water heaters. In the summer Air Curtains keep hot
humid air out and prevent the escape of air conditioning. The working principle of
Commercial Entrance Air Curtains is to provide the most effective air screen possible
without blowing so hard that it is objectionable to people passing through. Insect Control![]() Insect Control Air Curtains, sometimes called "Fly Fans," are used in food
processing plants, dairies, bakeries, bottling plants, restaurants, supermarkets,
hospitals, school cafeterias and other areas where the control of flying insects is
required. The powerful stream of air that is produced by an Insect Control Air Curtain is
an excellent deterrent to insects which will usually avoid the air stream simply because
of it's unnaturally high velocity. Cold Storage![]() When opened a door separating a cold storage area from a warm room permits a substantial loss of refrigerated air. Warm air flows into the cold room through the lower part. This results in energy losses, safety hazards in the form of condensation and icing on the floor and fog in the doorway; and possibly food spoilage. Strip doors used on coolers and freezers to reduce these effects impair visibility and are unpleasant to pass through due to condensation and frosting and accumulate dirt and possible bacterial growth. Studies have proven that Air Curtains, when properly sized and adjusted, are up to 85% efficient in controlling the flow of air through cooler and freezer doorways. If the cold storage door is open over one hour per day the Air Curtain is a cost effective way to save refrigeration costs. Installed on the warm side of the doorway the Air Curtain emits an air stream which reaches the floor at an angle and splits into two separate air streams. By properly adjusting the volume of the air and the angle of the nozzle, one air stream is made to balance against the other which is trying to leave the cooled room, while the other counteracts the warm air trying to enter. The correct Air Curtain sizing and adjustments must be made for each specific application so that a narrow, high velocity, low volume stream of air is projected over the entire opening creating a sufficiently stiff curtain of air. Built-in adjustments in the Air Curtain must include fully adjustable mounting brackets, variable volume controls and individually adjustable louvers in the nozzle. The narrow nozzle limits the amount of air in the doorway area and hence the turbulence, thus increasing the efficiency of the unit. In addition to providing a substantial energy savings and increased safety, Cold Storage Air Curtains can increase the time between defrosting almost four fold, depending on the particular freezer or cooler. Also, their ability to maintain the cold room temperature right up to the doorway improves product quality and increases the useful floor space. Summary![]() Over the long life of an Air Curtain system, tremendous benefits can be realized which pay for the system many times over. Some of these include:
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