Ok guys and gals... I've been trying to design an immersion chiller that will cut my cooldown rate by a factor of 3. Right now, I immerse the pot in another larger pot and fill that outer area with cold water and allow it to flow. Here's where I'm at. Right now, I estimate I've improved about 63%. I'd like any suggestions:
Pot: dp" hp"
Tubing: dt=3/8"
The coil will be half the diameter of the pot, and the there will be one coil of space inbetween each coil-wrap.
There will also be a riser tube coming up the center of the pot and out the side.
lcoil= pi*dp/2 Ncoils=hp/(2*dt) L= lcoil*Ncoils
L=pi*dp*hp/(4*dt) Acoil=pi*dt*L = pi^2 *dp*hp/4 Ariser=pi*dt*hp
Apot=pi*dp*hp (surface area of pot)
With my pot, that gives:
Acoil= 296 in^2 Ariser.1 in^2 Apot I0 in^2
Two relatively interesting things come out of this analysis. 1) The diameter of the tubing does not appear to provide much of an advantage, except that a smaller diameter tube will displace less of your wort when you dip it in the pot. 2) The outer edges of the pot have a great amount of heat transfer surface, which is hard to match with one set of coils.
Things my analysis ignores:
1) The better flow of water through the coils than what I now have in my current setup.
2) Dipping the coils will increase the height of the pot that the water sees, thuse giving more heat transfer surface.
Things my design ignores:
1) Natural circulation to improve mixing.
2) Paralell flows/higher flow rate = cooler water (multiple coils)