Push+Pull or Push+Push Dual Fans on Heat Sink

Anyone experimented with Push+Pull vs. Push+Push Dual Fans on a Heat Sink?

I know that Push Push give higher air pressure thus denser air (compressed) and that absorb heat more readily, However, depending on sink dims it also may give slower air speed which tends to negates the gains. On push push if your sink is close to cubed shape then the intake and exhaust area will be the same and it seems to that this is where a push push is better, yes push pull will still have somewhat faster air speed but very little but it seems to me that the better heat dissipation of the denser air will out rank the speed? This is all my crazy little head flatulating.


If I had a sink that is 120 X 120 X 60 then with push push the exhaust area will be half of what the intake area, is this where one should choose a Push pull set up? What do the experimenting prove?

All you are doing with push-push is having two fans fight each other. Don't believe us. You set up the experiment.

co⋅nun⋅drum
  /kəˈnʌndrəm/ Show Spelled Pronunciation [kuh-nuhn-druhm] Show IPA
Use conundrum in a Sentence
–noun
1. a riddle, the answer to which involves a pun or play on words, as What is black and white and read all over? A newspaper.
2. anything that puzzles.

Here's a a Riddle for you num drum "What compresses air on one side and causes a vacuum on the other side and it has blades that spins? Clue, it starts with "F" and ends with "AN"? Next time you watch the news pay attention to the word "Pressure" and see how it relates to air temperature. Also think of just how much pressure difference they are talking about. You cannot live without compressed air also contrarily to popular opinion air pressure is alway varying, when you feel wind that is a sign of varying air pressure.

Most sink have six side two of which air cannot flow through so if you have a fan on two sides in a push push configuration that still leaves two sides for air to flow out of and the point is to have them "Fight Each Other" to a point to raise pressure but remember, there is still two side for air to flow out of. Now pay attention next time before you blow sNOT all over someones post.

HI,
Some review test both setup push-push ans push-pull, it 's seem to be more effective in push-pull. Here is a link to one http://www.dragonsteelmods.com/ind [...] itstart=4.

In my setup I have noctua (NH-U12P) 2 fans in push-pull mode . The air flow direction I have his the following one.

a) air come from the top bye 2 noctua NF-P12 , 1 fan's blow on the memory stick the other directly on the heatsink, so the air have lower temps then ambient temps at least 1-2 c.

b) the air is suck and push thru the fins

c) the air little warmer is pull from fins and push on the back of the video card and it's still really low in temp. 27-28c.

d) on th side door I have 2 sctyhe s-flex 120mm to pull everything out of the case.

After testing a lot, is the best solution I can find for my setup, as you know the tj-09 need improvent in air flow departement.

In summer time this setup is more effective because the ambient temp is higher, and the difference forn the first fans his 3-4 cooler inside the case.
I take my temp reading with temp sensor connect to my fans controller. It's not a scientific test but for me that's do the job and give me measures pretty close to the reality.

I doubt the push/push configuration would be any good, not only does the airflow would be reduced, but if I remember correctly as any gas is compress, it releases heat and absorbs heat as it expands. Therefore the fans would push air together and as it compresses it would release heat into the heat sink.

By doing the opposite (pull/pull) you might do the opposite and as a finite amount of air is being taken in the heatsink to be pushed-out by the 2 fans, it might expand and absorb more heat.

Both those solutions however don't take into account the fan's performance under various air pressures or the impact on global casing air flow. If the setup creates a heat build-up inside the case, THAT might also negate or worsen any benefit. By having a push/pull setup, you can probably direct the hot air straight into the exhaust fan.

Never did the tests, this is mostly theoretical.

This bruhthakuga guy gets pretty annoying. He wants help, but complains every time someone disagrees with him.

Okay, what are your research findings? Have you tried your fan experiment yet?

I can Google that too btw.

I'm reading this with much interest, but there is one thing I wanted to add. I haven't done much testing but I did find two fans pointing the same direction did not make a big difference in air flow.

I have a CPU fan blowing directly on to a system exhaust fan. If I turn off the system exhaust, I don't notice any difference in the air flow exiting the system. I ended up just leaving the exhaust fan off (I have 3 exhausts to vent other air, this one has the HSF right up its ass). This reduced noise and didn't impact temperatures (maybe 1C at best, I didn't see any changes).

Just wanted to add my experience, take from it what you will. I'm not sure if that's even remotely useful, but posted it anywho.

I'm going to have to agree with conumdrum on this one. What he says just makes simple plain sense.

Also, the fact that you are arguing that the push push creates a higher pressure, is just funny, yeah maybe a slight increase, but then you went and contradicted yourself saying that their are still two exit points for which the air to go out of. And since there is an open point the air pressure will dissipate and go to equilibrium before the fans can really create a big difference in air pressure (which like Zenthar pointed out, could be a bad thing depending on your case temps).


Another good solution would be to do just one good high airflow fan.