4 ms·

Related: "3D Printed Heat Exchanger Uses Gyroids for Better Cooling" In short: 2x smaller, 2x more efficient https://www.youtube.com/watch?v=1qifd3yn9S0 https

by steeve 4y ago

Related: "3D Printed Heat Exchanger Uses Gyroids for Better Cooling" In short: 2x smaller, 2x more efficient https://www.youtube.com/watch?v=1qifd3yn9S0 https://www.youtube.com/watch?v=1qifd3yn9S0 In general, algorithmic engineering and AI designs are where 3D printing can really shine.

hinkley 4y ago
1/2 the volume, which is 40% smaller diameter (Assuming the length is kept, which as a drop-in replacement it would have to be?) The inventor talks about how the internal structure is based on minimizing surface area. That would of course reduce the material but in a heat exchanger don't you want to maximize surface area, not minimize it? Especially if your heat exchanger has a higher thermal transfer rate than the fluids. It makes me wonder if there's an answer to this design that's another 20% smaller.
- fnordpiglet 4y ago
  Yeah I did this about 3 years back using thermally conducting filament, the goal is exactly that - maximize surface area while maximizing float through the manifold. It’s actually stupidly easy to do these days with cura. Make your heat sink shape, say a cube, and slice it with zero wall thickness and gyroid infill. Then attach to a copper plate, and add a fan to the top. The problem is materials. Most people don’t have the ability to print in copper or aluminum. The thermally conducive filaments are absurdly expensive (like $120/kg) and the conductivity isn’t that great, so you can generally do better with a fin based thing in copper or aluminum. I think it would be possible to make a filament with aligned graphene in the filament that does really well, but I’m not that hard core. Another idea I have is building these out of graphene aligned in a super critical bath of silver. But that requires some serious equipment for the pressures and temperatures.
  - zmgsabst 4y ago
    For some geometries, you can also 3D print plastic and then cast in sand. That won’t get you the full power of 3D printing, but you can get many geometries you couldn’t otherwise.
    - fnordpiglet 4y ago
      Yeah I’ve thought of doing this. I probably will at some point. A gyroid should be castable
- ZeroGravitas 4y ago
  I believe 'minimal surface' is a technical term for these types of shapes: https://en.wikipedia.org/wiki/Minimal_surface https://en.wikipedia.org/wiki/Minimal_surface
- phkahler 4y ago
  >> The inventor talks about how the internal structure is based on minimizing surface area. That gives something like maximal strength for the amount of material. I suspect that's kind of related to reducing resistance to flow for a given atea, or something like that. They can increase surface area by shinking the gyroid pattern. But yeah, I thought the same thing when he said that - dude you want the maximum surface area!
AlexCoventry 4y ago
It's for a military helicopter? It looks more vulnerable to shrapnel than what I imagine it's replacing. Is that so, and is that an important consideration?
- metadat 4y ago
  This heat exchanger works by being surrounded by fuel. Thus if shrapnel is entering the vicinity of this part, the vehicle and it's occupants are probably already toast. Caveat / plot twist: If it's a kerosene or diesel chopper (common with Jet powered helicoptes), the fuel is much less susceptible to igniting due to a spark. Even still, how often does the outcome land on "If only the heat exchanger was more robust and impenetrable, everything would've turned out significantly better!" ?
  - AlexCoventry 4y ago
    Thanks.
- robocat 4y ago
  Presumably if the size of the heat exchanger can be reduced, the risk of getting hit by a bullet is reduced, and also it can more easily be placed behind protection.
metadat 4y ago
I wish they'd cut it open or otherwise show the cross section(s) of the interior in detail.
Incipient 4y ago
Like any field there is a lot more complexity they didn't cover in the video, but I would expect the designers did, at least in part. Particularly around pressure drops (especially in lube oil and fuel systems) and fouling (again, in a system like oil) Also I'm surprised they use S&T exchangers on a helicopter. I'd have expected plate or PCHEs, both are much smaller and more efficient. If they're using a S&T there may be a reason for it, but I'm not an aviation engineer.

by steeve 4y ago

hinkley 4y ago

1/2 the volume, which is 40% smaller diameter (Assuming the length is kept, which as a drop-in replacement it would have to be?) The inventor talks about how the internal structure is based on minimizing surface area. That would of course reduce the material but in a heat exchanger don't you want to maximize surface area, not minimize it? Especially if your heat exchanger has a higher thermal transfer rate than the fluids. It makes me wonder if there's an answer to this design that's another 20% smaller.

fnordpiglet 4y ago
Yeah I did this about 3 years back using thermally conducting filament, the goal is exactly that - maximize surface area while maximizing float through the manifold. It’s actually stupidly easy to do these days with cura. Make your heat sink shape, say a cube, and slice it with zero wall thickness and gyroid infill. Then attach to a copper plate, and add a fan to the top. The problem is materials. Most people don’t have the ability to print in copper or aluminum. The thermally conducive filaments are absurdly expensive (like $120/kg) and the conductivity isn’t that great, so you can generally do better with a fin based thing in copper or aluminum. I think it would be possible to make a filament with aligned graphene in the filament that does really well, but I’m not that hard core. Another idea I have is building these out of graphene aligned in a super critical bath of silver. But that requires some serious equipment for the pressures and temperatures.
- zmgsabst 4y ago
  For some geometries, you can also 3D print plastic and then cast in sand. That won’t get you the full power of 3D printing, but you can get many geometries you couldn’t otherwise.
  - fnordpiglet 4y ago
    Yeah I’ve thought of doing this. I probably will at some point. A gyroid should be castable
ZeroGravitas 4y ago
I believe 'minimal surface' is a technical term for these types of shapes: https://en.wikipedia.org/wiki/Minimal_surface https://en.wikipedia.org/wiki/Minimal_surface
phkahler 4y ago
>> The inventor talks about how the internal structure is based on minimizing surface area. That gives something like maximal strength for the amount of material. I suspect that's kind of related to reducing resistance to flow for a given atea, or something like that. They can increase surface area by shinking the gyroid pattern. But yeah, I thought the same thing when he said that - dude you want the maximum surface area!

AlexCoventry 4y ago

It's for a military helicopter? It looks more vulnerable to shrapnel than what I imagine it's replacing. Is that so, and is that an important consideration?

metadat 4y ago
This heat exchanger works by being surrounded by fuel. Thus if shrapnel is entering the vicinity of this part, the vehicle and it's occupants are probably already toast. Caveat / plot twist: If it's a kerosene or diesel chopper (common with Jet powered helicoptes), the fuel is much less susceptible to igniting due to a spark. Even still, how often does the outcome land on "If only the heat exchanger was more robust and impenetrable, everything would've turned out significantly better!" ?
- AlexCoventry 4y ago
  Thanks.
robocat 4y ago
Presumably if the size of the heat exchanger can be reduced, the risk of getting hit by a bullet is reduced, and also it can more easily be placed behind protection.

metadat 4y ago

I wish they'd cut it open or otherwise show the cross section(s) of the interior in detail.

Incipient 4y ago

Like any field there is a lot more complexity they didn't cover in the video, but I would expect the designers did, at least in part. Particularly around pressure drops (especially in lube oil and fuel systems) and fouling (again, in a system like oil) Also I'm surprised they use S&T exchangers on a helicopter. I'd have expected plate or PCHEs, both are much smaller and more efficient. If they're using a S&T there may be a reason for it, but I'm not an aviation engineer.