I have been browsing the internet looking for new fans for my H50 in a push/pull setup. I'm currently using Antec Tri-Cool fans in push/pull.
I've narrowed my choices down to the Scythe GentleTyphoon D1225C12B5AP-15 and S-Flex G. I know static pressure matters, and I have heard that these have good static pressure.
What would you guys recommend for me to switch my fans to? Or would you recommend keeping the Tri-Cools on my H50?
I will use a fan controller so I can choose between noise and performance. And I'm already using the fan controller on the Tri-Cools. Their motor sound annoys me, even on the lowest speed my fan controller will let me take them (I don't know what speed or percent. I just have dials that I can twist).
Originally static pressure referred to a state of equilibrium in which an equal amount of air is supplied to and exhausted from an enclosed space. For us the enclosed space is a pc case. What goes in goes out.
The type of case fans used, the number of fans, their location, and whether they are intake or exhaust fans all have an effect on static pressure. Case ventilation and airflow also affect static pressure. So does cable management.
Users often mention positive and negative pressure instead of static pressure. This is where discussions can heat up. Some users swear by positive pressure and some users swear by negative pressure. In each situation the equilibrium shifts away from static pressure. Personally I prefer to try and keep things as close to static pressure if possible. Silverstone and Lian Li have come up with some very unique case designs where static pressure is totally out of whack and the systems still cool very very well. They have shown that static pressure as it applies to pc cases is not all that important.
Static pressure as it relates to the fans themselves is different. It refers to the force of the air as it is exhausted/pushed by a fan. It's called static pressure but air pressure would have been a more appropriate phrase. The cpu heatsink fan needs to be able to force air between the heatsink fins. All those fins get in the way and restrict airflow. The fans that typically have a high static pressure are usually those with a higher rpm. The pitch of the fan blades is different to help increase pressure and they tend to be louder.
Personally I've had very good luck using the Scythe S-Flex 1600 rpm fans. Individual results will vary. That's the fun part about building your own system. You can experiment and find out what works best for you.
I don't know anything about water cooling so I am not going to offer any opinion or make any recommendations.
Just FYI, I'm using my H50 fans as intake, not exhaust. Forgot to mention it in my first post.
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When a blade pushes air into the computer, a low air pressure is created right outside the fan, and a high air pressure is created in the case, so when there is no blade pushing air in, the air flows back out, creating the little bit of air you feel going backwards behind the fan.
So it would make sense to constantly have blades pushing air in with very little gaps between the blades, which is what the GentleTyphoon does. The problem I can think of is if a low air pressure zone is created right outside the fan, and there are very little gaps between the blades, there isn't time to fix the low air pressure, and so you have less air moving in because the air that the fan gets to pull from is less dense.
The S-Flex would push more air with its blade, but less would actually get through the radiator because of the big gaps in between each blade. Air would move back out through those gaps because of the pressure differences between inside and outside the case.
So it seems like the GentleTyphoon moves lower-density air, but is more efficient in moving it, while the S-Flex moves more air, but less than 100% actually goes through the radiator.
Now, a question to counter what I just said. Would it even matter what fans or blade-types I use in a push/pull? The 2nd fan (the one closer to the middle of the computer, pulling air out of the radiator) would pull whatever air the first fan (the one attached to the case, pushing air into the radiator) pushed into the radiator, preventing a backflow out of the first fan.
I feel a little backflow of air out of my H50. It's not the type where it blows hard close to the fan, and then the speed of the air slowly decreases as you get farther away from the fan. It's the type where you can only feel it 1/4" away from the fan. After that, I can't feel any air moving. It's like a pocket of air that feels like it's a high pressure zone, but would make sense to be a low pressure zone.
And a room is so big that at it could probably quickly fix the low air pressure zone with a low CFM fan, but not fast enough with a high CFM fan because too much air would be getting pulled through the fan, while the air not being pulled by the fan (the air that has to correct the low pressure) would be moving slower because there is nothing pulling it.
I'm not good at this science. What I said might be totally false. Help?
Im afraid few people will be able to answer that question for you, even fewer to none on these forums or other enthusiast forums.. So the reason you won't get an answer is, no one has yet to test if high static pressure fans are better suited then lower static pressure fans with higher CFM for the Corsair H50's radiator..
And aren't Scythe Slipstreams supposed to have very low static pressure?
As a professional engineer by trade I often cringe a bit regarding many PC enthusiast's take on air flow assumptions. From an engineering standpoint, a PC case is really nothing more than a "tiny building". In a PC case, the air going in must always equal the air going out (think balloon) .....otherwise the case would either collapse or explode. If I block one of two exhaust fans with my hand most would assume that I just cut the case's exhaust by half....in reality, the intake fans will just push more air out the single exhaust fan and the extra static pressure that the extra flow creates thru the one remaining opening will decrease the flow thru the intake fans.
The term "static pressure" comes from the difference in air pressure in inches or feet of water. Imagine holding a piece of fish tank tubing filled 95% of the way with water.....with both ends open if you hold the ends together, the water is at the same level.....blow in one end (increase static pressure) and the levels will move, pushing the water level down on the blow (higher pressure end) and increasing it at the other. The difference between the two levels, defined in engineering terms, is "static pressure" as it represents the weight of the "static water level difference".
Now as it applies to heat sinks, back pressure is created by the friction of the air bowing thru the fins, the "sail area" of the surfaces blocking the flow and the eddy currents which such flow creates. You can experience this kind of pressure when you stick your head out a car window while a passenger in a car.....in that case your head is acting like the fins.
Back to PC's and HS's, the silentpcreview article states this about the Noctua NF-S12 fans
A very unusual fan from an Austrian company posing as a research institute. Unusual blade design produces more airflow than usual, but possibly at the cost of reduced pressure. Reports from real users have suggested that, despite measuring higher, actual cooling power is slightly less than it should be. Noise character was very broadband and became inaudible at a relatively high voltage. However, it lacks the buttery smoothness of some other fans. An effective choice for a case fan, but the questions raised about its pressure make us hesitate to recommend it for use on a heatsink.
I saw no such caveat follows with regard to the Slip Streams in the review. In my son's build, we used the EnerMax Magma fans which I have to say are amazing.