Fans for thermochill pa 120.3

[Soultribunal]

Originally Posted by MpG

But in lieu of wildly varying accuracy of the specs we're given, combined with the fact that static pressure increases roughly exponentially with fan speed, rpm isn't a bad reference point to start off at.

In some tests that I recall, even with a radiator restricting a fan, the airflow only dropped by 20-30%, which might suggest that the fan is still operating in the part of its curve more defined by cfm, as opposed to pressure. Wish there was more testing out there on this stuff.

I wish that was True MpG.

Static Pressure is the ability of a Fan to push through these obstructions.
And in testing the fans that I have, RPM's have nothing to do with it. My Wing 12's (not yet here in canada ) Had about 500RPM less than my R4's but still maintained almost the same static pressure.

Fin Design has a lot more to do with it. But you would get less of a drop on a Radiator with a fan exibiting a higher pressure.

Anywho , I will be doing more testing once I get my new Fluke. But its a $800+ investment for a hobby.

ST

[MpG]

Originally Posted by Soultribunal

I wish that was True MpG.

Static Pressure is the ability of a Fan to push through these obstructions.
And in testing the fans that I have, RPM's have nothing to do with it. My Wing 12's (not yet here in canada ) Had about 500RPM less than my R4's but still maintained almost the same static pressure.

Fin Design has a lot more to do with it. But you would get less of a drop on a Radiator with a fan exibiting a higher pressure.

Anywho , I will be doing more testing once I get my new Fluke. But its a $800+ investment for a hobby.

ST

Yes, that's what static pressure is, but it's not unlike head pressure in a water pump - you'll never actually see that peak static pressure except in a zero-airflow scenario. The fan will have a pressure/flow curve, which will interact with the restriction curve of whatever object the fan is trying to blow past, and the two will result in a given pressure drop and airflow. I don't doubt that you can have a scenario like the one between your Wing 12's and the R4's. But how do they act between the two extremes of max airflow and max static pressure? Agreed, fin design definitely influences the numbers (not unlike the reasoning behind a variable-pitch propeller), but I'm just not entirely convinced we're seeing the promised improvements in the actual situations the fans actually get used in.

While I can't call it anything professional-grade, when I did my own screwing around with fan performance on radiators, I just wasn't seeing any magic bullets beyond rpm and fan thickness. Maybe it's because I didn't bother trying out fans that were known to be poor, but there just weren't huge temperature differences, even when I deliberately tried to magnify them. While the different fans' noise definitely varied at the same speed, the performance/rpm outcomes were actually more consistent. Mind, this was all a year or two ago now, and there's been some interesting stuff released since then. I would have loved to try out the Gentle Typhoons and SS's new Penetrator fans.

On another note, you're getting a meter that will actually handle case fan levels of pressure? Sweet!!!

[Soultribunal]

Your best bet first is to keep a given scenerio the same and change one variable.
For me it was a switch out between fan types, same case, same cooler, run at Max Speed.

The Yate Loons I've had, had great airflow and perfect RPM (2000RPM, 88CFM) however they didn't do as well as say R4's (1900RPM, 69CFM).

But this is why I really want a meter to do this type of thing. I want actual Numbers.
Yes I will be getting a new toy. I've already played with an older Fluke Meter and it really opened my eyes to actual airflow numbers.

ST