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dpb

wrote:
dpb wrote:

wrote:

I'm thinking about using a recent Taurus auto radiator or a Ford or GMC
pickup radiator to heat water with hot sunspace air, but I'm concerned that
a) it's hard to find specs for radiator performance, and b) a mechanic says
an aluminum core radiator might crud up with corrosion in less than a year
with oxygenated water and no antifreeze.

An old all-copper car radiator might not corrode, but it might not have an
electric fan, and it might be hard to find one, and a replacement if needed.

How many Btu/h can an auto radiator move from 150 F air to 140 F water,
using its electric fan, with no wind? ...
For some detailed answers you might look at

Parametric studies on automotive radiators
Applied Thermal Engineering, Volume 27, Issues 11-12, August 2007, Pages
2033-2043 C. Oliet, A. Oliva, J. Castro and C.D. Pérez-Segarra

Aha. Thanks. Now where did I put the August issue...

My gut feeling is performance won't be very good w/ only a 10F
temperature differential.

I'd like to get 800 Btu/h-F, like a MagicAire 2347.

In round numbers, an automotive radiator operates on roughly a 100F
difference or greater and except at idle, has a pretty high airflow rate.

I'm wondering how it will do without wind, just its own fan.

Well, as noted, they are designed for that as the next comment noted,
but still have about a 200F differential instead of your proposed 10F.

Somebody else noted already they're well over-designed for the minimum
capacity in order to account for idling in traffic on hot days w/ full
A/C load, etc.,

At idle, it might have to dissipate 25% of 1 gph, about 30.5K Btu/h...

suppose ibut still the temperature differences are around 200F for coolant
and 100F for air temperatures for the most part.

G = 30.5K/(200-100) = 305 Btu/h-F?

Coolant flow rates are pretty high, as well.

If the thermostat's open.

And if it ain't, it ain't doin' nuttin' useful...

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