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Jimbo Mahoney · 05-27-2005, 06:17 AM

I'm gonna get shot here with my 'precision' themal probes but still......

OK, I'm using cheapo themal probes typical of PC shops:

http://store.over-clock.com/Miscellaneous2.html

BUT, I do have one accurate (well, +/- 0.1'C) digital thermometer which I used to calibrate them against.

OK, so, my ambient temp is 23'C, water at 26'C and total heat load of 290 watts.

3 / 290 = 0.01 C/W

Is this possible? :shrug:

The radiator is HUGE (40cm x 30cm) and double-pass. I also have 4 x 120mm fans pulling air through (shroud depth approx. 5cm). Each one is rated at 44cfm, giving a total (unrestricted) flow of 176 cfm, although I have overvolted my PSU so the 12v line is actually 13v, so the (unrestricted) flow will be somewhat higher, perhaps 190cfm.

Flow rate is approx. 5 lpm (approx. 1.3 - 1.4 US gpm).

Looking here:

http://thermal-management-testing.com/ThermoChill.htm

It seems the largest rad is 0.02 C/W, but my rad has an approximate surface area of 1200 cm^2

, whereas the 120.2 only has 288 cm^2

If it makes any difference, the radiator I use seems to match quite closely Cathar's suggested 'ideal', although it is thicker, at 1.75" rather than the 0.75" -> 1" suggested by Cathar. The fin density is quite low though, so it really shouldn't be very air-restrictive.

Thanks for any suggestions as to how realistic this 0.01 C/W is. Given the high airflow and huge surface area, it may seem reasonable?

05-27-2005, 06:17 AM	#1
Jimbo Mahoney Cooling Neophyte Join Date: Jan 2005 Location: UK Posts: 96	My radiator has a C/W of 0.01? I'm gonna get shot here with my 'precision' themal probes but still...... OK, I'm using cheapo themal probes typical of PC shops: http://store.over-clock.com/Miscellaneous2.html BUT, I do have one accurate (well, +/- 0.1'C) digital thermometer which I used to calibrate them against. OK, so, my ambient temp is 23'C, water at 26'C and total heat load of 290 watts. 3 / 290 = 0.01 C/W Is this possible? :shrug: The radiator is HUGE (40cm x 30cm) and double-pass. I also have 4 x 120mm fans pulling air through (shroud depth approx. 5cm). Each one is rated at 44cfm, giving a total (unrestricted) flow of 176 cfm, although I have overvolted my PSU so the 12v line is actually 13v, so the (unrestricted) flow will be somewhat higher, perhaps 190cfm. Flow rate is approx. 5 lpm (approx. 1.3 - 1.4 US gpm). Looking here: http://thermal-management-testing.com/ThermoChill.htm It seems the largest rad is 0.02 C/W, but my rad has an approximate surface area of 1200 cm^2 , whereas the 120.2 only has 288 cm^2 If it makes any difference, the radiator I use seems to match quite closely Cathar's suggested 'ideal', although it is thicker, at 1.75" rather than the 0.75" -> 1" suggested by Cathar. The fin density is quite low though, so it really shouldn't be very air-restrictive. Thanks for any suggestions as to how realistic this 0.01 C/W is. Given the high airflow and huge surface area, it may seem reasonable?