Cooling efficiency - Noctua 200 on two 240 Radiators
1 hour ago, hannibalxali said:q = hc A dT
I have nothing to do so I'll try to provide some more details;
q = heat transfer (how good the cooling is, usually measured in watts)
h = heat transfer coefficient (some number depending on materials, not really important here as it's constant for both cases)
A = the heat transfer area (area of the radiator (this is actually the area of all the fins combined, but as that is linearly related to the area of the rad itself, we can base the calculations on that for simplicity
)
dT = the temperature difference between the air and the radiator or heatsink
the airflow caused by the fan causes dT to be greater. The more airfow, the lower the temperature of the air, the bigger the difference in temperature between the hot radiator and cold the air, hence the bigger dT. No fan would mean the hot air doesn't leave the radiator quicly, so dT is much lower, therefore q is very low as well, and the cooling performance sucks.
Now we get to the interesting part.
In this equation, the importance of dT and A is the same (they're multiplied together) but dT does not equal airflow. Airflow does indeed affect dT, but I don't think the relation between airflow and dT is linear, meaning that 10% more airflow will result in less than 10% more dT (still more, but not quite 10%)
Which means that more area is technically more important than more airflow as 10% more area will (according to the equation) result in 10% better cooling, whereas 10% more airflow will result in say (made up value) 8% larger dT which means only 8% better cooling.
1 hour ago, hannibalxali said:The calculation shows that the four small fans will beat the big fan by 3% only. 47100/48364 ≈ 97/100
Here airflow in CPM and area are multiplied together, meaning the increased importance of area is ignored, meaning your calculation is slightly biased towards the single fan setup. The single fan setup has more airflow, but less area, which is worse than less airflow and more area.
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now