I think that was post was best of the bunch. I wish we could of built off that post.
Engineering: What qualities make something great or a mess? *spawn from XBox One X*
- Thread starter MrFox
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I think that was post was best of the bunch. I wish we could of built off that post.
Pre-heat your toaster at a low burninator setting before popping the first slice(s) of bread into it. Return bread-burninator dial back to whatever makes nice toast. All set!
Edit: we might see a thread closing soon, or will there be a breakfast toast spinoff thread next?
I meant in the context of a fan specs. The fan completely obstructed will have no flow and max pressure. With nothing in it's path it's max flow and no pressure. The zero flow point determine it's static pressure. Usable operating point is at least halfway and for reasonable rpm it's still way lower than we would ideally prefer. If there was a fan with super high static pressure at 500 rpm it would be a revolution I guess, we could have extremely tight fins and huge surface area. But they can't cheat the laws of physics.
You'll see the ps3/4 fans have been using blades that are slanted backwards. This raises the effective static pressure, and lower the effective flow. Allowing a lower rpm than the typical blower gpu design.
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I think I'm following you here.
The ideal is very high static pressure, more pressure = more cooling, assuming no other restrictions on the formula.
So the ideal blower fan is one that creates more static pressure at lower flow rates to generate more cooling with less noise.
How this is accomplished is through various means of tweaking both the heatsinks (shape and length, + other characteristics) and the fans, speed and fan blade design.
So are other restrictions/cons as a result of increasing static pressure and decreasing flow?
Wouldn't by design, a low flow have more challenges with having to cool a longer system (ie the motherboard) if the flow is low? The static pressure I imagine cannot be kept constant through the whole motherboard.
Aw yisss.... We're officially switching to cooling strategies.
Let me sober up and gather my thoughts.
Axial fans also move higher volumes of air for their given space too. It comes down to where you are receiving your intake air, where you are exhausting it and how much space you have to dedicate to the fan itself.
Centrifugal compressors have their place however, as they are easier to manufacture, provide significant pressure ratio increase with each rotor (hence shorter engines) and are quite FOD resistant making them ubiquitous for smaller and cheaper turbine engines, especially turboprops...............oh wait.........wrong tech........
But back to cooling, isn't the local flow inside the case technically dynamic (moving) meaning it should be termed dynamic pressure? Or is it static in terms of being constant? Anyways, the idea of having high pressure needs to be treaded carefully, as we don't want to increase the air pressure inside the case to the point where it's adding to the buildup of heat, like a pressure cooker. Hence, we need to be able to exhaust that excess pressure effectively, and with it the heat it carries.
Centrifugal compressors have their place however, as they are easier to manufacture, provide significant pressure ratio increase with each rotor (hence shorter engines) and are quite FOD resistant making them ubiquitous for smaller and cheaper turbine engines, especially turboprops...............oh wait.........wrong tech........
But back to cooling, isn't the local flow inside the case technically dynamic (moving) meaning it should be termed dynamic pressure? Or is it static in terms of being constant? Anyways, the idea of having high pressure needs to be treaded carefully, as we don't want to increase the air pressure inside the case to the point where it's adding to the buildup of heat, like a pressure cooker. Hence, we need to be able to exhaust that excess pressure effectively, and with it the heat it carries.
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It's just about finding the best tool for the job.
The static pressure is the fan specs when fully obstructed. It's a point of reference for designing a system, not an operational number. Same for max flow.
If the design goal is a very low rpm, for low noise, axial gets into an exponential problem.
Rule of thumb (varies wildly but to illustrate) Half the rpm changes the specs to: half the max flow, quarter the static pressure. 4 times less is 16 times lower pressure. The specs might look amazing at 3000 rpm and will look unusable at 750 depending on the application.
In those small consoles you need a deep and dense heatsink with an equivalent pressure drop that is too much at the required flow necessary to remove a lot of heat (100-150w) at low rpm. It leads to being almost always limited by pressure specs, not flow specs. (again, only at low rpm)
The "pressure" we're talking about here is something like 5 mmH2O. That is the pressure underwater at 5 milimeter deep, or 0.0005 bar, or a compression ratio of 1:1.0005. It's not pressurized in the sense people think.
The static pressure is the fan specs when fully obstructed. It's a point of reference for designing a system, not an operational number. Same for max flow.
If the design goal is a very low rpm, for low noise, axial gets into an exponential problem.
Rule of thumb (varies wildly but to illustrate) Half the rpm changes the specs to: half the max flow, quarter the static pressure. 4 times less is 16 times lower pressure. The specs might look amazing at 3000 rpm and will look unusable at 750 depending on the application.
In those small consoles you need a deep and dense heatsink with an equivalent pressure drop that is too much at the required flow necessary to remove a lot of heat (100-150w) at low rpm. It leads to being almost always limited by pressure specs, not flow specs. (again, only at low rpm)
The "pressure" we're talking about here is something like 5 mmH2O. That is the pressure underwater at 5 milimeter deep, or 0.0005 bar, or a compression ratio of 1:1.0005. It's not pressurized in the sense people think.
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Tkumpathenurple
Veteran
That might as well have been a final year quantum physics lecture, because I understood none of it.
Thanks though
Thanks though
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