Calculating power dissipated in a heat exchanger

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The discussion focuses on calculating the power dissipated in a heat exchanger for a PC watercooling loop. The original poster questions the validity of their calculations, particularly regarding the conversion of flow rate from liters per hour to kilograms. It is clarified that the specific heat capacity and mass density values used in the calculations apply only to distilled water, and the user must obtain the correct values for their specific cooling fluid. The importance of using the correct density to convert flow rates accurately is emphasized. Accurate calculations are essential for effective cooling performance in the watercooling system.
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TL;DR Summary
Is this calculation right?
2024-0804 Rad Heat Calc-C.png

I want some help in figuring out any flaws in these calculations. I was given this picture but I was looking into it and found some things which are either wrong or don't apply to my watercooling loop (for my PC).

First thing I notice is that litres per hour divided by 3600 (hours to minutes) gives units in kg.

I don't know if it maters (since I can't find specific numbers on heat capacity of the fluid) but I'm not using distilled water but this stuff (it was £20 when I bought it):
https://mayhems.store/mayhems-x1-clear-premixed-watercooling-fluid-5-litres.html

For background information here is the thread where I got the picture from:
https://forum.aquacomputer.de/weite...t/?s=d38a467e13100c26b8c0293df1023b395dbbd769

Also appologies if this is the wrong section of the forums.
 
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SgtSixpack said:
TL;DR Summary: Is this calculation right?
The "flowchart" shown is a correct (but cumbersome) way to calculate the cooling capacity based on the simple formula in the gray box, which I enlarge here for clarity:
1744986155606.png

Note though that the specific figures used there (kg/sec = liters-per-hour/3600 and Cp = 4.178) apply only to distilled water. To use the formula with your cooling fluid, you'll need to contact the manufacturer to obtain the proper values of mass-density and heat-capacity for that particular product.
 
Thanks for the response. I'm still not happy with the first part of the calculation.

LPH/(a constant)
can't end up as kg from my limited knowledge of mathematics.

To find the mass in kg, one would need something like density of water. Guess I'm right/wrong according to google:

"One litre of water has a mass of almost exactly one kilogram when measured at its maximal density, which occurs at 3.984 °C. It follows, therefore, that ⁠1/1000⁠ of a litre, known as one millilitre (1 mL), of water has a mass of about 1 g, while 1000 litres of water has a mass of about 1000 kg (1 tonne or megagram)."
 
SgtSixpack said:
I'm still not happy with the first part of the calculation.
LPH/(a constant)
can't end up as kg from my limited knowledge of mathematics.
To find the mass in kg, one would need something like density of water.
That's exactly right. Use the formula:$$\text{mass-rate}\left(\text{kg/s}\right)=\text{mass-density}\left(\text{kg/m}^{3}\right)\times\text{volume-rate}\left(\text{m}^{3}\text{/s}\right)$$For water, the mass-density is ##\text{997}\approx\text{1000}\,\text{kg/m}^3##, but as I said, you'll need to contact your supplier to find the mass-density of your cooling fluid.
 
Thanks for explaining that. I can't like your post unfortunately.
 
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