just bought a bonnie and thinking...

[OverClockedNub]

I was planning on making a shroud for it and having 4 86cfm panaflo's in push/pull... but then I got this (possibly half baked) idea.

Since the air flow pattern out of these fans is a pretty direct cone, the air from the push fans will probably not touch/affect the outer edges of the heatercore.

So I am wondering, why not run all 4 fans in pull? The shroud would have to be lop sided anyhow, so rather than making it get narrow for the fans, why not expand it and have all 4 fans on one side of the heatercore?

Has anyone tried this before or seen this done?

[Conumdrum]

I havent. But it's worth a try!

[xtreeme]

I was planning on making a shroud for it and having 4 86cfm panaflo's in push/pull... but then I got this (possibly half baked) idea.

Since the air flow pattern out of these fans is a pretty direct cone, the air from the push fans will probably not touch/affect the outer edges of the heatercore.

So I am wondering, why not run all 4 fans in pull? The shroud would have to be lop sided anyhow, so rather than making it get narrow for the fans, why not expand it and have all 4 fans on one side of the heatercore?

Has anyone tried this before or seen this done?

I have tried it - the noise level was horrible, like a turboprop engine :D Didn't gain anything either.....

[OverClockedNub]

I have tried it - the noise level was horrible, like a turboprop engine :D Didn't gain anything either.....

:-/ No gain at all? Were you running in push or in pull on the fans? I was thin king of setting up in pull.

[xtreeme]

Tried both pull and push with two fans connected together - no gain at all. And as I said - the noise was horrible - the reason to the noise was probably because of the impellers close to each other.....

tip: if you rip out the motor/impeller part of old fans you have excellent shrouds ;)

On the other hand - we know that Mercury marine motors use duoprops, but that are two impellers on the same shaft, so maybe glueing two impellers together will give improved performance ?????????

[jr1]

If i'm not mistaken you will have to have a little space between the fans and have something between them to stop the air from spinning around with the second fan or get the fans to spin in opposite direction of eachother

The duoprop spins the opposite way of eachother to stopp the water from turning around in the same direction as the propellars and to reduce cavitation

[xtreeme]

The duoprop spins the opposite way of eachother to stopp the water from turning around in the same direction as the propellars and to reduce cavitation

Yeah, I know - got one ;) - but that will be impossible to do here - but what will happen with twice the amount with fan blades ? Mounted so they will be twice as long/wide (don't really know how to put this down in writing :D )

[OverClockedNub]

Actually I did not mean having the fans stacked. I meant having all 4 side by side
sort of like this
xx
xx
all in pull on one side of the heater core. I realize that this would be wider than the heatercore itself, but not by that much and there would be a shroud putting it all together.

[jr1]

I'm not an expert but my logic sense say that it would help

[xtreeme]

Actually I did not mean having the fans stacked. I meant having all 4 side by side
sort of like this
xx
xx
all in pull on one side of the heater core. I realize that this would be wider than the heatercore itself, but not by that much and there would be a shroud putting it all together.

My bet is that fullcover shrouds and fans in a push/pull configuration will be better.
You can even make the shrouds so you can attach 2 fans on them for that matter....

[ArchEnemy]

I wish I could find back the test they did a couple of years ago with "dual-fans". Basically the conclusion was that the only way to get it to work effectively is that there has to be a precise relation between both fans RPM, like they shouldn't be running at the same speed. It would be great if someone knows where to find it, if he recalls it.

[xtreeme]

http://www.youtube.com/watch?v=SCGJ42w02EU


http://www.youtube.com/watch?v=MpZk03I2Ing


Remember earprotection.... http://www.delta.com.tw/product/cp/dcfans/download/pdf/GFB/GFB120x120x76.2mm.pdf

:D

[dark bishop]

Dont worry, youll be happy with your boneville, I am with mine and I've only got a couple of scythe slipstream 1200rpm's on it. Even with the fan on low it had no problem cooling my phenom 2 overclocked while folding.