• We’re currently investigating an issue related to the forum theme and styling that is impacting page layout and visual formatting. The problem has been identified, and we are actively working on a resolution. There is no impact to user data or functionality, this is strictly a front-end display issue. We’ll post an update once the fix has been deployed. Thanks for your patience while we get this sorted.

Air doors

W

wacki

Senior member
Some stores and even some open refrigerators will use air doors. Basically a thin sheet of fast moving air that insulates the fridge/store from the outside. Does anyone know how this words? I would think the venturi effect would cause the air to mix
 
Originally posted by: Kelnoen
I don't think it's just to do with insulation (especially in fridges), they are used to stop insects and bugs getting through also.

http://www.tmi-pvc.com/air_doors/howairdoorswork.html

Basically the jet of air points slightly outwards so any wind towards the entrance is guided upwards by the moving air (like up a ramp).
Click to expand...

Wouldnt it make more sense to have the flow go down? That way youre working with gravity.
 
it's interesting

To think that something like air could form a "wall"....

Kinda a weird idea for a layman to understand, thouhg it makes sense (with the air jets)
 
Originally posted by: TheoPetro
Originally posted by: Kelnoen
I don't think it's just to do with insulation (especially in fridges), they are used to stop insects and bugs getting through also.

http://www.tmi-pvc.com/air_doors/howairdoorswork.html

Basically the jet of air points slightly outwards so any wind towards the entrance is guided upwards by the moving air (like up a ramp).
Click to expand...

Wouldnt it make more sense to have the flow go down? That way youre working with gravity.
Click to expand...

Remember, air is floating inside an atmosphere of air. Gravity won't help/hinder (ok, cold air is heavier than warm air and hot air is lighter than warm air, but the difference is not significant for this).
Why the air is directed upward and not downward? Maybe to let the dust settle on ground, and not raise it.
 
strange, in the ones i've seen, the air is always directed downwards.

These are really common in Hong Kong, Almost every store that keeps its door open uses one, though the air has always been directed downward.
 
Originally posted by: Calin
Originally posted by: TheoPetro
Originally posted by: Kelnoen
I don't think it's just to do with insulation (especially in fridges), they are used to stop insects and bugs getting through also.

http://www.tmi-pvc.com/air_doors/howairdoorswork.html

Basically the jet of air points slightly outwards so any wind towards the entrance is guided upwards by the moving air (like up a ramp).
Click to expand...

Wouldnt it make more sense to have the flow go down? That way youre working with gravity.
Click to expand...

Remember, air is floating inside an atmosphere of air. Gravity won't help/hinder (ok, cold air is heavier than warm air and hot air is lighter than warm air, but the difference is not significant for this).
Why the air is directed upward and not downward? Maybe to let the dust settle on ground, and not raise it.
Click to expand...

If your goal is to keep dust particles out then gravity would play a role. I cant think of a situation where you would have an "air wall" and want more dust to flow in. A downward draft would almost always be better. I would think you would use air that is cooler than ambiant and direct it downwards. This would make for minimal mixing of the air and allow the least amount of dust in.
 
You must log in or register to reply here.

TRENDING THREADS

Back
Top