Using ionic wind for airflow?

StoleMyOwnCar

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I was watching a Linus video where he had this huge passive heatsink on the back of a motherboard and noted how the airflow caused by him simply nudging it slightly caused a considerable amount of heat dissipation ().

Noctua is releasing a fanless passive cooling solution:
https://www.pcmag.com/news/noctuas-fanless-cpu-cooler-launches-for-109-but-expect-it-to-run-hot

But it runs hot. The weak point in all of these is the giant heatsink is great... but no airflow just cripples it.

That got me thinking. We had MIT release a plane that moved using basically no moving parts:
https://news.mit.edu/2018/first-ionic-wind-plane-no-moving-parts-1121

Why has this air current generation method not made it into passive cooling? Just a tiny amount of airflow would make a gigantic difference, and it should be much quieter than any moving fan, so... why hasn't it? I'm just a layman in the scientific field so maybe I just don't understand amount of energy required to generate an air current... but size wise each of the elements in the MIT plane seemed pretty thin. And it's not like it takes much airflow to make a gigantic difference.
 

toast0

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If you really just need a tiny amount of airflow, most fans are near silent at 30%, if you have decent layout, one fan pushing out the top will get everything moving in the right direction (or one pulling in on the bottom). Using fiddly new technology when a low speed fan would work is kind of silly.
 

StoleMyOwnCar

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If you really just need a tiny amount of airflow, most fans are near silent at 30%, if you have decent layout, one fan pushing out the top will get everything moving in the right direction (or one pulling in on the bottom). Using fiddly new technology when a low speed fan would work is kind of silly.

First, depends on how good your ears are. I can hear basically any fan operating if the room is quiet enough. So no, not quite.

Second this isn't just about the airflow requirements, it's about basically having a flat, solid state air moving technology. As in, the form factor. If you put a fan somewhere, you need to sacrifice space somewhere else, usually in heatsink size or the form factor of the device. Using this, I feel like we would be able to have basically a flat heatsink without any fan space taken up. So no, I feel there is reason for it. Especially in small form factor space...

Third, "fiddly new technology" is how we get advancements. You're kind of at best indirectly answering the topic.
 

Nobu

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Still going to need a fan to get the hot air out of the case, unless you have an open hole or the ion engine works on holy case panels.
 

StoleMyOwnCar

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Still going to need a fan to get the hot air out of the case, unless you have an open hole or the ion engine works on holy case panels.

I mean that CPU cooler from Noctua that I linked was definitely not meant to go into a closed system, so yeah I think holes are a given.

My Surface Pro 7 has holes in it, so yes, holes are a giv--... hmm..

Actually let's suppose we were in a closed device with no holes, that had an aluminum body. Even having it circulate its own air should prove beneficial because it would spread the heat around the case and cause more of the hot air to indirectly come in contact with the outside air via the aluminum, increasing the surface area for cooling... well, I'm not sure how big of a difference that would make in the end.

Actually in devices that small, I feel like this is where it would be best. You don't need much airflow to make a difference, and you probably literally can't make a fan that small.

The whole reason I made this topic is that I was hoping maybe someone in the know would say, "Well okay it's impractical because the amount of current you need for any sort of airflow is A, hence it would drain modern mobile batteries too fast to be practical, at least in its current state". Or something like that.
 

Nobu

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I mean that CPU cooler from Noctua that I linked was definitely not meant to go into a closed system, so yeah I think holes are a given.

My Surface Pro 7 has holes in it, so yes, holes are a giv--... hmm..

Actually let's suppose we were in a closed device with no holes, that had an aluminum body. Even having it circulate its own air should prove beneficial because it would spread the heat around the case and cause more of the hot air to indirectly come in contact with the outside air via the aluminum, increasing the surface area for cooling... well, I'm not sure how big of a difference that would make in the end.

Actually in devices that small, I feel like this is where it would be best. You don't need much airflow to make a difference, and you probably literally can't make a fan that small.

The whole reason I made this topic is that I was hoping maybe someone in the know would say, "Well okay it's impractical because the amount of current you need for any sort of airflow is A, hence it would drain modern mobile batteries too fast to be practical, at least in its current state". Or something like that.
I meant an open hole (singular), vs a grill/mesh.

In a small case, with the heatsink right next to the holes, it might do just fine. But in a midi/mid/full tower case, where the heatsink is far from the vent holes, the air will tend to want to stay in the case (unless the holes are above the heatsink and that's where the air is being pushed). In a larger case, what will happen is the heat will be rapidly transferred to the air (good!), and then the air will be heatsoaked (like a heatsink with no fan on a powerful cpu, bad!). You need to get the hot air out, and that won't happen fast enough in a large case with no fans (Except maybe at idle).
 

Nobu

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I think it's cool tech. I don't think it's capable of cooling (on it's own) a desktop computer in a standard tower case, unless you're okay with cooking the motherboard components.
 

StoleMyOwnCar

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I meant an open hole (singular), vs a grill/mesh.

In a small case, with the heatsink right next to the holes, it might do just fine. But in a midi/mid/full tower case, where the heatsink is far from the vent holes, the air will tend to want to stay in the case (unless the holes are above the heatsink and that's where the air is being pushed). In a larger case, what will happen is the heat will be rapidly transferred to the air (good!), and then the air will be heatsoaked (like a heatsink with no fan on a powerful cpu, bad!). You need to get the hot air out, and that won't happen fast enough in a large case with no fans (Except maybe at idle).
I see, you're coming it at from the standpoint of "eliminating all fans in the case". I was mainly just zeroing in on the CPU cooler by itself, since Noctua was pumping out a passive CPU cooler. That being said, temperature differences between inside air and outside air alone should create a natural draft between the inside of the case and the outside of a case. Unless you were cooling a behemoth CPU (unlikely if you were depending on passive healing), I really doubt that the inside of the case would reach pressure cooker levels or anything, and the distribution of hot air around the case should naturally cause it to flow out more efficiently, too. Well, that, and having a grate right above the CPU and having the thing blow up isn't exactly difficult. Warm air rises, too, so that helps.

It's kind of illogical to even attempt this inside of a full tower case, anyway, simply because we really don't have any GPU that can be fully passively cooled. Although I'd be eager to see this on a low TDP GPU to see if it could be cooled like this, maybe via a blower setup, but an ionized blower setup. But basically if you're using a full or mid tower, it's really unlikely that you would just have the CPU in there, and your GPU came with fans. You're screwed from the getgo lol.

So yeah, some manner of small factor system was kind of the understood context.
 

Nobu

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I see, you're coming it at from the standpoint of "eliminating all fans in the case". I was mainly just zeroing in on the CPU cooler by itself, since Noctua was pumping out a passive CPU cooler. That being said, temperature differences between inside air and outside air alone should create a natural draft between the inside of the case and the outside of a case. Unless you were cooling a behemoth CPU (unlikely if you were depending on passive healing), I really doubt that the inside of the case would reach pressure cooker levels or anything, and the distribution of hot air around the case should naturally cause it to flow out more efficiently, too. Well, that, and having a grate right above the CPU and having the thing blow up isn't exactly difficult. Warm air rises, too, so that helps.

It's kind of illogical to even attempt this inside of a full tower case, anyway, simply because we really don't have any GPU that can be fully passively cooled. Although I'd be eager to see this on a low TDP GPU to see if it could be cooled like this, maybe via a blower setup, but an ionized blower setup. But basically if you're using a full or mid tower, it's really unlikely that you would just have the CPU in there, and your GPU came with fans. You're screwed from the getgo lol.

So yeah, some manner of small factor system was kind of the understood context.
Actually, I've experienced just this, in a case with both case and cpu fans. Granted, they were all set to pull air in, but there were exhaust vents open and it was just an r5 3400g.
 

NattyKathy

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The ionic method of generating air current has been known for a awhile, since home air purifying ionizers became a thing in the '70s-'80s. It's not a good method for moving air for cooling purposes because to get a sufficient draft requires a really powerful ionizer which isn't small, isn't silent (BUZZZZZZ), and can create a significant amount of ozone which isn't great in a confined (if ventilated) space full of electronics and plastic.
 

StoleMyOwnCar

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The ionic method of generating air current has been known for a awhile, since home air purifying ionizers became a thing in the '70s-'80s. It's not a good method for moving air for cooling purposes because to get a sufficient draft requires a really powerful ionizer which isn't small, isn't silent (BUZZZZZZ), and can create a significant amount of ozone which isn't great in a confined (if ventilated) space full of electronics and plastic.

Good stuff. MIT was talking about using it for drones and whatnot, so I wonder if they've overcome any of these limitations with recent tech.
 

NattyKathy

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Good stuff. MIT was talking about using it for drones and whatnot, so I wonder if they've overcome any of these limitations with recent tech.
From what I recall about the MIT study (I remember checking it out back in 2018 when it dropped), most of the special tech in their project was related to making the voltage booster more compact as well as the use of high-density Lithium batteries in order to match the vehicle's mass into the propulsion available. Barring some big advance that was not part of that study, there's an upper limit to the amount of power that can be driven through an atmospheric ionizer because it requires scaling the voltage up to absurd levels. Past a certain point the terminals will flash over and the corona turns into an arc and the power converter has a Bad Time. Moving the terminals further away from each other prevents the arcing but widen the spacing too much and it will negate the benefits of increasing the voltage and the scaling hits a wall. So the focus is on power electronics miniaturization and optimizing battery density.

As cool as ionic propulsion is, it's unlikely to become an option as a high-power propulsion source without some radically new tech that gets past the power density scaling wall.
 
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