Heat Exhchanger Selection (what is kw/C)

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To select a suitable heat exchanger for cooling 28 liters per minute from 70°C to 25°C, it is essential to calculate the required cooling capacity using the kw/C metric. The kw/C value indicates how much power the heat exchanger can remove for each degree Celsius of temperature rise. For this scenario, the energy to be extracted is approximately 92 kW/s, leading to a required kw/C of 2.04. It is crucial to ensure that the chosen radiator can achieve this cooling effect at the specified flow rate. Accurate calculations are vital, as the kw/C metric may not hold true at extreme energy inputs.
Su Solberg
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Hello, everyone.

I have a problem in finding a suitable heat exchanger for cooling coils.
I would like to cool down 28 lier/min; from 70 Celsius to at least 25 Celsius.

I wonder how to fit "kw/C"(performance spec.) to my case so that i can find a suitable heat exchanger.

Thanks for your help.
 
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kw/C is a measure of how much power (kw) the heatsink can remove for each degree C temperature it rises.
Once the heat sink reaches the temperature of the incoming hot fluid it is obviously not going to remove any more heat.

You can work out the amount of energy to be extracted each second to cool 28/60 litres of water by 45 C and then from the kw/c work out how much this will heat the heatsink.

Note - this is just an approximation - the kw/c is only correct for a certain amount of power. At very high or very low energy inputs it might not be accurate..
 
mgb_phys said:
kw/C is a measure of how much power (kw) the heatsink can remove for each degree C temperature it rises.
Once the heat sink reaches the temperature of the incoming hot fluid it is obviously not going to remove any more heat.

You can work out the amount of energy to be extracted each second to cool 28/60 litres of water by 45 C and then from the kw/c work out how much this will heat the heatsink.

Note - this is just an approximation - the kw/c is only correct for a certain amount of power. At very high or very low energy inputs it might not be accurate..

Thanks for your reply.

To confirm your meaning, is that mean suppose the water will reject heat 92kw/s (from 70->25;Q=M*Cp*(T1-T2) ) then the kw/C required is 92kw/45C=2.04kw/c.

That's mean I have to find a radiator that can achieve 2.04kw/c cooling effect at 28l/min?

Thanks for your help.
 
LEt see, you need 60 liters per minute of Water to drop from 70 down to 25 C?
 
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