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How much heat will this evaporator remove?

How much heat will this evaporator remove?

How much heat will this evaporator remove?

(OP)
Quick question.

I just want to get a ballpark rough idea of how much the air charge temperature would drop through an evaporator of this size at 800cfm with 80deg ambient air temp vs. 300deg ambient air temp.  

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewIte...

Im thinking about building an intercooler and trying to decide whether to place the evaporator before or after the turbo.

RE: How much heat will this evaporator remove?

If the evaporator is big enough the air temp will approach the atm wet bulb temp.  Temp drop will be approx 90% of the difference between the inlet air temp and the wet bulb temp for initial estimating purposes. Like I said, if the evaporator is big enough.

Problem is that the atm wet bulb is different in the summer and winter.

RE: How much heat will this evaporator remove?

Anwer given by 1969grad is not correct for this evaporator.  This is a refrigerant evaporator and not a evaporative cooling device.  The temperature drop through the unit depends on air flow and refrigerant flow rates.  At 80F entering air temp you should be able to get 65F or a little lower leaving.

RE: How much heat will this evaporator remove?

Sorry about that.  Looks like I pulled the trigger too fast.

My comments are relative to cooling air via evaporative cooling.  Typical applications are for combustion air into a gas turbine.

RE: How much heat will this evaporator remove?

Jon,
At a face(1.33 sqft) velocity of 600 FPM, 800 CFM should produce about 20,000 BTU/h and a TD of about 25*F
BTU/H = CFM x TD x 1.08 or TD = BTU/h/CFM x 1.08

RE: How much heat will this evaporator remove?

Hi there!

It seems that we arrived at the point to look for the the evaporator data, in order to know/calculate the global conductance factor "U" to use in the formula:             Q=[(Heat Transfer Surface Area)* U * (Log. Delta Temperature or Mean Delta Temperature, whatever most convenient)].

In this system, in terms of heat balance, if you have more than one unknown parameter, you should find another physical condition/equation or boundary condition to relate. Hoping this can be of some help.
Merry Christmas to All
zzzo  

RE: How much heat will this evaporator remove?

(OP)
Thanks for the replys,

Roughly how much more heat would this same evaporator remove if it were placed down stream of the turbo in 300deg air?

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