Heavy Duty Industrial Process Air Curtains
An air door or air curtain is a device used for separating two spaces from each other, usually at the exterior entrance. The most common configuration for air curtains is a downward-facing blower fan mounted over an opening. Normally this opening is an entrance to a building, and the air curtain is intended to help keep flying insects out by creating forceful turbulence. It also helps keep outside air out, avoiding cold drafts by mixing-in warm air from the air curtain. The fan must be powerful enough to generate a jet of air that can reach the floor.
The most effective air curtain for containing heated or cooled air inside a building with an open door will have a high face velocity at the opening, generated by top-down flow, recovered by a recirculating air plenum and duct return to the source fans. This configuration is available for new construction, but difficult to provide in existing buildings. The air curtain is most effective with low exterior wind velocity. At higher wind velocities, the rate of air mixing increases and the outside air portion of the total face flow increases. Under ideal conditions of zero wind, the effectiveness of the air curtain is at its maximum.
For industrial conditions, high face velocities are acceptable. For commercial applications like store entrances, user comfort dictates low face velocities, which reduce effectiveness of separation of exterior air from interior air.
Non-heated air curtains are often used in conjunction with cold storage and refrigerated rooms. Airflow through a door depends on wind forces, temperature differences (convection), and pressure differences.
Air curtains can be used to save energy by reducing the heat transfer between two spaces, although a closed and well-sealed physical door is much more effective. A combination is usually utilized; when the door is opened air curtain turns on, minimizing air flow from inside to outside and vice versa
A variety of installation options are available to cater for building and architectural features such as suspended ceilings but the most common is simply bolting the unit to the wall above the doorway and connecting a single phase supply and switch to the unit.
Power consumption is negligible for a normal sized doorway opening – about 300 W. Some units can even be specified with a heating element to warm an enclosed area.
Air curtains block the flow
An air curtain simply creates a block in the air flow through an opening. The air velocity of the curtain must then be great enough to direct the resulting velocity downward and ensure that a small part of the air stream goes out while the main air flow comes back into the room.
Canadian Air Systems Co. is a world’s leading designer and manufacturer of industrial process air-curtains and environmental air barriers for a variety of industrial process applications. For special applications Canadian Air Systems offer high volume and high penetration tangential air curtains with highly laminar airflows.
For additional information please refer to http://www.nis-co.com/aircurtain/Index.html.
Oleg Tchetchel
Industrial Air Systesm Developer
Canadian Air Systems
http://www.nis-co.com/aircurtains/Index.html
http://www.nis-co.com/airknife/Index.html
Oleg Tchetchel
Designer of Air Moving Systems
Canadian Air Systems
http://nis-co.com/contact/Index.html
