Fan/Wind/Air to Cool Water

[Vig16]

I had another thread started on the topic of cooling water, but I figured I'd start a different one since I'm exploring a whole new avenue.

I'm trying to cool 8 ounces of 70 deg C water down to 38 deg C. I want to do this all in 2 minutes, but with as low a cost as possible. I was thinking of using a fan or air pressure of some short to do this. The only question I had is how do I determine the pressure or amount of "wind" that I'll need to obtain the temperature drop?

My initial test was to dispense 3 ounces at 70dC and then have room temperature water dispensed into the 70dC water. In my two attempts at this, I got the temperature in the cup down to 44dC and 47dC, but am still off by a bit. I was thinking that if I introduced air of some sort into the flow of room temperature water, that I'd be able to have the final water temp drop the 5-10dC that I'm looking for.

Does anyone have any insight as to how I'd go about calculating the amount of cooling that I'd need to get to the desired temperature?

Thanks so much!!

 

[IRstuff]

That was already answered in your other thread, with the specific heat calculations.

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize

 

[Vig16]

So the ~250 W would still be the answer I'm looking for?

 

[IRstuff]

No, you're looking for the amount of heat energy.

However, your current problem statement seems to be in violation of your original problem statement, since you are now introducing apparently previously unheated water.

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize

 

[Compositepro]

Vig you really don't seem to have a good grasp of the concept of what heat is, and how it differs from temperature. I suggest you read the chapter on heat in a basic physics text. There are also plenty of on-line resources (other than asking questions here). There is no substitute for taking the time to study the basics.

Maybe you should just consider the benefit of a few ice cubes to solve your problem.