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Chilled water

Chilled water

Chilled water

(OP)
Hello
a quick question that envolve enthalpy prob.
I need to find the flowrate of chilled water ( Pipe size and everything is unknown).
Assuming worst case summer ambeint air conditions.
supply water 42F
Return water 62F

Using thermal energy is not gonna help mass flowrate is unknown so teh flowrate
h = 500 q dt
where
h = total heat removed (Btu/h)
q = water flow rate (gal/min)
dt = temperature difference (oF)
Heat removed unknown.

Q = 500*GPM*(Delta T)
500 is constant
GPM= flow in gallons per minute
Delta T = temperature difference in Fahrenheit between the supply water and the return water.
Q = load in BTUh
Yet I don't have the Load....
any suggestion ? what kinda formula must bethere. /

RE: Chilled water

(OP)
Forget to ask on how to deal with Humidity ??

RE: Chilled water

Without knowing what the load is there is no way to solve the problem. You need to know how much total heat (BTU/Hr) you are trying to remove before you can proceed.

I'm not a real engineer, but I play one on T.V.
 A.J. Gest, York Int./JCI  

RE: Chilled water

Why does this sound like a homework problem?

RE: Chilled water

winky smile

I'm not a real engineer, but I play one on T.V.
 A.J. Gest, York Int./JCI  

RE: Chilled water

you're missing the load as others have indicated.  

Let's assume that you know your airflow and air temps, then the load is Q=(CFM)*(4.5)*(Delta-h), where 4.5 is a "constant" and Delta-h is the change in enthalpy (BTU/Lb dry air).  Now you can determine GPM.

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