I’ve noticed supermarket fridge doors open outwards, this causes a vacuum process doesn’t it.
Could energy be saved if sliding doors were used instead of opening doors?
How much vacuum would sliding doors create compared to opening outwards?
Doors that slide past each other give less access by their very nature
causing a longer time having to be open due to the awkward angle
at which one must reach for the frozen food now out of reach.
That still leaves the question of the vacuum and who is going to push it around.
Ogmog said:
Doors that slide past each other give less access by their very nature
causing a longer time having to be open due to the awkward angle
at which one must reach for the frozen food now out of reach.
thinking about double sliding doors now…
but the vacuum issue would still remain
as it’s still a matter of unequal temp/air density
Ogmog said:
Ogmog said:
Doors that slide past each other give less access by their very nature
causing a longer time having to be open due to the awkward angle
at which one must reach for the frozen food now out of reach.
thinking about double sliding doors now…
but the vacuum issue would still remain
as it’s still a matter of unequal temp/air density
We have sliding doors on the big food storage fridges in the hospital kitchen.
‘Vacuum’ has never been a problem.
Nor do i remember it being a problem with swinging doors on walk-in fridges elsewhere.
They do have air inflow and outflow, you know.
Tau.Neutrino said:
I’ve noticed supermarket fridge doors open outwards, this causes a vacuum process doesn’t it.Could energy be saved if sliding doors were used instead of opening doors?
How much vacuum would sliding doors create compared to opening outwards?
> Could energy be saved if sliding doors were used instead of opening doors?
No, because with sliding doors you have to overcome friction for the whole of the opening distance. With the vacuum from outward-opening doors the vacuum only lasts a small fraction of a second until the internal and external pressures equalise.
There’s also another issue here. The vacuum helps to press the doors against the seals which keeps the cold air in. With sliding doors, the vacuum leaks out around the doors even when nobody has the doors open, with the result that the cold air leaks out and more energy is needed for refrigeration.
> What vacuum from opening outwards?
Supermarket fridges have an internal volume between 2 and 20 cubic metres. For my local supermarket it’s about 10 cubic metres. The expansion on outwards opening before the pressure equalises is no more than about 0.002 cubic metres. So we’re talking about 0.0002 times the ambient air pressure of about 100,000 Pascals, which is 20 Pascals.
For a refrigerator at home, it’s more like 100 Pascals. Would you want a sliding door on your home refrigerator?