I was out on a sailboat recently for a weekend. Naturally we had a cooler full of ice-cold frothy malted beverages and such. At some point, I asked someone to drain the cooler and they replied, “but there’s all that cold water in there keeping things cool?” So what’s the answer to this eternal riddle - do items in the cooler stay cold longer if the water is continually drained, or if the ice is allowed to
melt and never drain?
Having chilled water in the ice makes a big difference. First off, it tends to chill the beer faster than ice alone. Second, it keeps the beer cool longer than simply adding ice alone. We add a small amount of cold water to the original ice mix when traveling or fishing, simply because of it’s added cooling ability.
My W.A.G.? I think it has something to do with surface area of the can or bottle. Ice is jagged and will leave quite a bit of the surface area untouched. Having an ice water bath surrounds the entire can or bottle. It makes sense to me, and I know from experience it makes a big difference.
Also the mass of material at 32 degrees is important. More stuff at cold temperatures = longer time it stays cold.
If you can remove the water and replace it with COLD air, than yes, draining the water is a good idea.
If you are replacing the water with WARM outside air, it’s better to leave the water in place.
Water has a high heat capacity – it takes a (relatively) lot of energy to change its temperature. From my point of view, the high heat capacity + surface area + insulating effects + mass (just throwing all of the previous post’s good points together) = don’t drain the cooler.
I am just trying to get your point of view, PeeWee: Why would you drain the cooler? What was given as the reasoning behind this? It may be a damn good point. Does it have to do w/ the heat exchange of water at its freezing point? Please respond. I would like to take everything into consideration.
there is no doubt that the ice water will cool drinks faster then ice alone. but as to keeping longer, this is my WAG:
air is a good insulator and as such causes the ice to stay longer. add water even at 32F and the insulating properties of the air is gone and the water is in constant contact with the cooler walls AND the ice causing the greatest heat loss (well actually coll loss) through both convection and conduction.
Thankfully, contact with the cooler walls should not matter in the slightest. Your average (good) cooler is built with either a layer of air or a layer of vacuum betwen the outer and inner walls, thus negating the need for the insulating effect of air on the inside of the cooler.
In the case of a cheap styrofoam cooler, well, who would use that anyway? Still, I would suspect that the exchange of a few millimeters of air for water (the average distance of the ice from the cooler wall isn’t that far) would not increase the heat transfer significantly (I was a chemical engineering student. “Significantly” means plus or minus 20%). Not to mention, the added mass of cold water will allow it to be colder longer.
Incidentally, my question is what beer was doing out on a boat anyway. Too many states out there have made drinking and driving illegal, but not drinking and boating… grrr.
LL
Ex-freaking-actly.
If the air is warm, then I would try the water you are fishing in - because the water likely isn’t above “room temperature”.
Better yet, get a boat with a fridge.
From my experience on Phish tour this summer, I have a lot of experience with coolers. No, you should not drain the water until the cooler is completely empty and you’re just toting around an empty cooler which you want to be light. The water will keep cold in there, too, for days at a time, as a matter of fact. The water is almost as good as the ice it once was.
Oh yeah, and a full cooler always stays cool better then a partially full cooler. The more air space you have, the more outside air will rush in every time you open the cooler. Thus, the coolness of the ice, water, and beverages is wasted cooling down the warm air. (OK, Mr. Wizard, it’s actually the heat from the air transferring info the cold objects, but give me a break.)
One thing for sure. A ice/water bath will cool beverages the quickest. If you have a desire for a cold one and all the cans are warm, they can be made icy cold in about five minutes with the following technique.
Put the can into a container large enough to hold it with a tray of ice plus water to cover. Make sure the container is large enough to allow the can to move around. An eight quart saucepan works fine. Use no more than two cans at a time. Now hold the can and gently slosh it back and forth to allow maximum heat transfer/unit of time.
Movement is important here to disrupt the boundry layers of cold beer which develops on the inside of the the can and warm water which develops on the outside of the can and therefore slows down the transfer of heat.You will have to switch hands to keep them from freezing but your beer will be cold in less than five minutes. Contrast this with setting the can in the freezer(and probably forgetting it there) where it will take about 30 minutes. And if you leave it in too long, the water will freeze out of the beer when the you open it and the pressure is released. And we all know what that tastes like.
So now you have two cold ones, enough for two people to have one. Now add two more and more ice and let them chill by themselves while you and your friend enjoy the cold ones. By the time you finish them, the others will be cold.
Hmmm…all my beer is gone before the ice even melts, so I don’t know what you’re talking about.
Is that a problem?
Boating and drinking isn’t illegal but driving a boat drunk IS illegal (at least it is in Wisconsin, Indiana and Illinois where I do most of my boating).
In my estimation the real problem is no licensing programs required for boaters. Send you $50 registration fee to the state, put the stickers on your boat and poof…instant boat driver.
As an avid scuba diver I find this particularly disconcerting. Too many boaters see a dive flag and seem to say to themselves, “Hey, pretty flag…let’s go check it out.” That’s being glib but the reality is most just seem to ignore it (you’re supposed to stay 150’ away). I’ve seen pictures of divers run over by boats…VERY ugly.
Sorry for the hijack. Please return to your regularly scheduled thread…
Wow, thanks for all the great responses! I think I need to be more specific though, so as to weed out all the extraneous factors. Let’s say you’ve got two coolers, side by side, both filled with ice and beer (or Root beer if we must-I never said the Captain was drinkin…), lids closed. Now, which will stay colder longer assuming we never open the lids, and one is continuously drained (through a plug which isn’t letting warm air in!), and the other is just left to hold the water/ice mixture? I’m thinking the one that get’s drained.
When the cooler is drained, what replaces the water. When that water leaves the cooler, something has to take its place, or each time you drain more out, you have more of a vacuum.
I am sure that one that isn’t drained is the one that will stay cooler, especially since it takes more energy to warm (or conversely, to cool) water than air.
Basically water has a molecular structure that transfers heat to nearby molecules fast and efficiently. In large quantities, it takes a relatively long time to heat water and conversely a long time to cool. Increase the salinity of the water and you can cool it to below freezing. If you want really cold beer, add rock salt to the ice and water.
This is the same principle that is used in Ice Cream makers.
Here is an excerpt from an online encyclopedia:
Chemically, water is a compound of hydrogen and oxygen whose formula is H2O. The two H-O bonds form an angle of about 105°-an arrangement that results in a polar molecule, because there is a net negative charge toward the oxygen end (the apex) of the V-shaped molecule and a net positive charge at the hydrogen ends. Consequently, each oxygen atom is able to attract two nearby hydrogen atoms of two other water molecules. These hydrogen bondings keep water liquid at ordinary temperatures. Because of the hydrogen bondings between molecules, the latent heats of fusion and of evaporation and the Heat Capacity of water are all unusually high. For these reasons water serves both as a heat-transfer medium (e.g., ice for cooling and steam for heating) and as a temperature regulator (the water in lakes and oceans helps regulate the climate).
Assume: Two identical coolers, same environment, same initial beer temp (must be warmer than or equal to 32 deg. F.). Outside Air temp (OSA) is greater than 32 deg F. also.
Energy (heat) going into the coolers is the same initially and is driven by the temperature difference between the OSA and the beer/ice/water mix. Beer decreases in temp until it is the same temp as the water/ice. Ice melts while water/ice/beer maintains 32 deg temp. If water is drained, and warm air doesn’t enter, and the coolers volume stays the same, then you would start decreasing the air pressure, and the ice would melt faster, draining more water but decreasing the convective heat gain to the portions of the cans touching air and not ice. The energy flows into the cooler based on temp difference with OSA though, so the partical vacuum wouldn’t have much of an impact. It is just silly, but kind of fun to think about. Eventually the cooler could be empty of all but beer, water vapor, and small amount of saturated air. The evaporating water would have a slight cooling effect, but probably not enough to notice.
Basically, heat flows into the cooler from the outside based on the temp. difference, cooler surface area, and insulation. The water is cold and has mass, therefore assuming no cooler openings, the one with the water will stay cooler longer.
I always though people drained coolers to keep sandwiches and stuff dry, and to make them easier to carry. If they are doing it to keep things cooler, they are working on bad assumptions.
[Your average (good) cooler is built with either a layer of air or a layer of vacuum betwen the outer and inner walls]
I have never heard of a cooler that uses a vacuum for insulation, a thermos yes not a cooler.
I’d still venture to guess that under some circumstances that the ice would last longer if water was drained. Some of the circumstances might be high external temp and low insulation properties of the cooler walls. I still think the liquid water acts like the thermal conductive grease used on cpu to fan connections. it fills in all the cracks and uneven surfaces of the ice and the cooler walls, and the beer.
If I had an automatic icemaker I’d try an experment, but I’m not filling up those stupid little trays for this.
here’s an experiment someone can do at tthe office. get 4 stryofoam cups with 4 lids. fill 2 with the smae amount of ice. double each cup to add to the insulation. poke a hole in the bottom of one of the 2 cups near the edge. this will act as the drain for one. rotate the cups with the holes in them so the holes are 180’ apart, this will limit the amount of warm air entering the cup w/ the hole in it. wait it out, put in some o.t. if needed. take a few peaks throughout the day, this will simulate taking the beers out. and let us know where the ice last the longest.
Oh yea, put a double lid on each one.
I’d do it myself, but don’t have thoses cups here
Ahh c’mon K2. Don’t give up now. Where’s your sense of scientific intrigue?
Whoever mentioned the salt had it completely right. I forgot to mention that we have done this too. It works like a charm. I got this tidbit from watching my father make homemade ice cream in a tub filled with ice and rocksalt as a kid. We tried it in our own cooler and found we had super-cooled water chilling the refreshments.
The idea of a vacuum and all that went over my head. I hardly think those variables are going to be present in the cooler question the O.P. referred to. I mean, warm air as opposed to cold and how the cooler would react? Who cares. Your opening the thing quite a bit. A lab may be one thing, but out on a boat or wherever, you have new conditions that come into play.
I’ve seen from time to time wine cooling machines in the liquor store that use super-cooled water swirling around in a tank. You stick your bottle in and within minutes you have a completely chilled bottle of wine. Super cold water is the key.
If I were you, I’d fill the cooler up with beverages first. Nexr, pour over and pack as much ice as possible around it. Then, fill about a third of the way up with cold water. Finally, dump in some salt and slosh it around. You should have cooler drinks faster and longer than any other method.