Block of ice on the floor for cooling?

[Svenn]

Sorry if this has been discussed before but I was reading this guy's calculations:

https://www.burakkanber.com/blog/cooling-a-room-with-2-liters-of-ice-calculation/

and it made me think why couldn't one just buy those cheap 10lbs block of ice on hot nights and simply place it on the floor of our vehicle near a fan or something?  My space is 120 cubic feet and is fairly well sealed and insulated... it's basically a really big cooler; and if those blocks of ice can cool a yeti  to 40 degrees for days couldn't they bring the ambient temp down 5 or 10 degrees in my space at night?

 

[poncho62]

Do you have drainage holes drilled in the floor?

 

[BradKW]

Where in his calculation does it take into account that the ice melts gradually over hours? It seems to me that he is figuring numbers based upon the ice releasing all it's " cooling energy" at once...

 

[ccbreder]

Before mechanical air conditioning, buckets of ice with fans were used to cool hospital patients. The ice was brought from northern states and stored underground to be used in southern heat. Buckets of ice. Not 1 small bottle. I will not be surprised when those calculations are proved wrong by magnitudes of error. Try it yourself. A frozen water bottle is not that hard to find. See how that feels on a hot day.

 

[highdesertranger]

what about the part when they say, "Assume that the efficiency of heat transfer from the bottle to the room is 100%." ha ha ha, NOTHING is 100% efficient. highdesertranger

 

[Spaceman Spiff]

Conservation of energy.  Where else but the room will the ice take the heat energy?  I suppose convection from whatever it is sitting on (floor?) would reduce it from 100%, but it would be pretty small.

BTW: heat energy is flowing into the ice, cold is just the absence of heat.

We would swipe a 20# block of dry ice and use a fan behind to cool a physics lab at school one summer (until we were caught).  Tried it in a pan of alcohol, which cooled the room well, but we weren't feeling very good after about 20 minutes.

 -- Spiff

 

[Every Road Leads Home]

Well i'm currently sitting in 100 degree Boston Heat and it sucks. Have a fan blowing on me. I froze a gallon jug of water a month ago for an overnight trip, i'm gonna pull it out of the freezer and stick it in front of the fan and see if I notice a difference. The room im in is 8x11. Thermometer is reading 91 for room temp. Lets put this very unscientific test to work.

 

[Hippiechk]

Conservation of energy.  Where else but the room will the ice take the heat energy?  I suppose convection from whatever it is sitting on (floor?) would reduce it from 100%, but it would be pretty small.

BTW: heat energy is flowing into the ice, cold is just the absence of heat.

We would swipe a 20# block of dry ice and use a fan behind to cool a physics lab at school one summer (until we were caught).  Tried it in a pan of alcohol, which cooled the room well, but we weren't feeling very good after about 20 minutes.

 -- Spiff

Cold falls...if you do want to effect an old fashioned (ONLY FROZEN WATER) ice based cooling effect, have it over you.

As for that block of solid carbon dioxide in the lab...Our lab was sealed with a recirculation filtration system...the oxygen sensors wooda gon nutz!

Must have been decent liquor! The vapors from a few litres of isopropyl could well have blinded the closest people. Could have flash dried some stuff in the cryofluid though, that's always fun under the fume hood...

 

[BradKW]

If the calculation for the 2-liter bottle results in a 20 degree drop then I would caution EveryRoadLeadsHome to be careful when using a gallon, might be needing a jacket or blanket.
Guy

lol  

 

[DannyB1954]

Ever hear of a 3 ton Air conditioning unit? A refrigeration ton is the cooling power of one ton of ice melting over 24 hours. A 12,000 BTU A/C unit is a one ton. Now a Btu is the amount of energy needed to change one pound of water one degree Fahrenheit, (between 33 and 211 degrees). As water changes state, solid to liquid it absorbs more heat than the one BTU per pound.

Another way to look at it is for the same cooling capacity as a 12,000 BTU A/C unit, you will have to melt 83 lbs of ice per hour, (2000lbs / 24hours)

 

[ZoNiE]

Ever hear of a 3 ton Air conditioning unit? A refrigeration ton is the cooling power of one ton of ice melting over 24 hours.  A 12,000 BTU A/C unit is a one ton. Now a Btu is the amount of energy needed to change one pound of water one degree Fahrenheit, (between 33 and 211 degrees). As water changes state, solid to liquid it absorbs more heat than the one BTU per pound.

Another way to look at it is for the same cooling capacity as a 12,000 BTU A/C unit, you will have to melt 83 lbs of ice per hour, (2000lbs / 24hours)

You're going to need a bigger van :dodgy:

 

[BradKW]

heh, so 265 gallons per ton, say 4 liters per gallon, 2 liters is about 1/500th of a ton, one ton = 12k btu... So:

2 liters frozen ~ 24 BTU? brrrrr!

 

[DannyB1954]

If the air blew across the ice and then onto you, it would cool you, but not the van.
When I was doing refrigeration repair for the food industry it would cost the business more to make the ice for a beverage than the beverage would cost. It takes energy to make ice. Syrup is cheap.\
Being in direct contact with the ice would make it more efficient. Stuff it down your pants, sit on it, lay on the bottle with the back of your neck in contact with the bottle etc.

 

[highdesertranger]

dang, stuff it down your pants. I don't think so. highdesertranger

 

[29chico]

If the air blew across the ice and then onto you, it would cool you, but not the van.
When I was doing refrigeration repair for the food industry it would cost the business more to make the ice for a beverage than the beverage would cost. It takes energy to make ice. Syrup is cheap.\
Being in direct contact with the ice would make it more efficient. Stuff it down your pants, sit on it, lay on the bottle with the back of your neck in contact with the bottle etc.

Direct contact with the block of ice, now we are getting somewhere! 

I remember reading many years ago how so much blood flows thru one's butt area that sitting directly on a block of ice could well prove fatal from hypothermia in about an hour.  Way cool...

 

[DannyB1954]

Direct contact with the block of ice, now we are getting somewhere! 

I remember reading many years ago how so much blood flows thru one's butt area that sitting directly on a block of ice could well prove fatal from hypothermia in about an hour.  Way cool...

They used to send down blocks of ice for miners to sit on to cool off.