Fan curves: I can make them
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Fan curves: I can make them
Hello I just thought everyone should know that I have a calibrated wind tunnel that I can use to make fan curves (which are curves plotting fans airflow output across different system backpressures).
I dont have any fans of note that are worth testing but at some point i plan to test some a slipstream, sflex and gentle typhoon.
I dont remember the accuracy of the airflow or pressure measurements but I believe it works quite well down to 2 cfm and ? inchesH20.
Reply to this or message me if you have anything in mind or fans you wish to send me to test. I can also test system response curves of heatsinks (which is where you see the pressure needed to blow X CFM through a heatsink).
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These are useful because it gives air flow (@ 0 back pressure AKA stated values in spec sheets) static pressure (@ 0 CFM) and everything in between which I can also take at various voltages (only 12-7-5 since they take some time). If a fan has low pressure @ 20 CFM then its airflow will probably drop to something like 10 CFM when blowing through a large heatsink. If you are trying to push air through a dense heatsink, you would look at something like the 2 inchesH20 mark and find the fan with the highest airflow, and best acoustics.
Attached is an example of how you know what the airflow of a system will be if you have a fan curve and system response curve.
I dont have any fans of note that are worth testing but at some point i plan to test some a slipstream, sflex and gentle typhoon.
I dont remember the accuracy of the airflow or pressure measurements but I believe it works quite well down to 2 cfm and ? inchesH20.
Reply to this or message me if you have anything in mind or fans you wish to send me to test. I can also test system response curves of heatsinks (which is where you see the pressure needed to blow X CFM through a heatsink).
--------------------------------------------
These are useful because it gives air flow (@ 0 back pressure AKA stated values in spec sheets) static pressure (@ 0 CFM) and everything in between which I can also take at various voltages (only 12-7-5 since they take some time). If a fan has low pressure @ 20 CFM then its airflow will probably drop to something like 10 CFM when blowing through a large heatsink. If you are trying to push air through a dense heatsink, you would look at something like the 2 inchesH20 mark and find the fan with the highest airflow, and best acoustics.
Attached is an example of how you know what the airflow of a system will be if you have a fan curve and system response curve.
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Re: Fan curves: I can make them
1. Accuracy on absolute measures isn't that important if you can compare fans using the same measure that is consistent and reproducible.chico1st wrote:I dont remember the accuracy of the airflow or pressure measurements but I believe it works quite well down to 2 cfm and ? inchesH20
2. What you have done is very impressive. Please consider reposting this message here:
viewtopic.php?f=9&t=58350
3. Have you done any testing since you posted this message?
Re: Fan curves: I can make them
How about a picture of your setup?
Re: Fan curves: I can make them
sorry i didnt come to the forum for a while because the thread hadn't had any activity.
At least that's what it looked like to me.
You get zero back pressure by having a fan on the exhaust of the tunnel and having 0 mm/H20 pressure in the middle of the tunnel.
I cant post pictures as this is my setup at work. I'm allowed to use it for whatever but I doubt i can post pictures of the setup, work secrets i suppose.How about a picture of your setup?
The test is very reproducible, its a professionally calibrated and serviced wind tunnel.1. Accuracy on absolute measures isn't that important if you can compare fans using the same measure that is consistent and reproducible.
The issue with this test, is that the fans are just blowing into some random tunnel/enclosure which doesnt have a known back-pressure. If he was blowing the air through a certain heatsink at least you would know the airflow through that heatsink.Some Really Nice Fan tests
viewtopic.php?f=9&t=61442
At least that's what it looked like to me.
You get zero back pressure by having a fan on the exhaust of the tunnel and having 0 mm/H20 pressure in the middle of the tunnel.
Good idea, i will post there shortly.2. What you have done is very impressive. Please consider reposting this message here:
viewtopic.php?f=9&t=58350
I've done tests since then but I do them for work and few fans have looked worth testing. We use high-airflow high-pressure fans usually so I cant post anything you guys would be interested in. Although I tested one fan which had amazing airflow/pressure and 80 dBA! (We have an anechroic chamber but there is so much noise in the building it wont go below 30 dBA).3. Have you done any testing since you posted this message?
Re: Fan curves: I can make them
After you post here:chico1st wrote:Good idea, i will post there shortly.
Which PWM, CPU or Specialty Fan do you Want SPCR to Review?
viewtopic.php?f=9&t=58350&start=30
Please read this thread and consider making a contribution, if you can.
5dBA 120mm Fan
viewtopic.php?f=9&t=61591
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Re: Fan curves: I can make them
yes pleaseces wrote:Please read this thread and consider making a contribution, if you can.
5dBA 120mm Fan
viewtopic.php?f=9&t=61591
Re: Fan curves: I can make them
Do you find that discussion as disorienting as I do?goatsandmonkeys wrote:yes pleaseces wrote:Please read this thread and consider making a contribution, if you can.
5dBA 120mm Fan
viewtopic.php?f=9&t=61591
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- Posts: 91
- Joined: Wed Oct 06, 2010 6:32 am
- Location: new york
Re: Fan curves: I can make them
It's like, I think I get it, but I couldn't replicate the results.ces wrote:Do you find that discussion as disorienting as I do?goatsandmonkeys wrote:yes pleaseces wrote:Please read this thread and consider making a contribution, if you can.
5dBA 120mm Fan
viewtopic.php?f=9&t=61591