Illinois researchers demonstrate extreme heat exchanger with additive manufacturing:
Used in most major industries – including energy, water, manufacturing, transportation, construction, electronic, chemical, petrochemical, agriculture and aerospace – heat exchangers transfer thermal energy from one medium to another.
For decades, heat exchanger designs have remained relatively unchanged. Recent advancements in 3D printing allow the production of three-dimensional exchanger designs previously thought impossible. These new and innovative designs operate significantly more effectively and efficiently but require specific software tools and design methods to manufacture the high-performance devices.
[...] "We developed shape optimization software to design a high-performance heat exchanger," said William King, professor of Mechanical Science and Engineering at The Grainger College of Engineering and co-study leader. "The software allows us to identity 3D designs that are significantly different and better than conventional designs."
The team started by studying a type of exchanger known as a tube-in-tube heat exchanger – where one tube is nested inside another tube. Tube-in-tube heat exchangers are commonly used in drinking water and building energy systems. Using a combination of the shape optimization software and additive manufacturing, the researchers designed fins (only made possible using metal 3D printing) internal to the tubes.
"We designed, fabricated and tested an optimized tube-in-tube heat exchanger," said Nenad Miljkovic, associate professor of Mechanical Science and Engineering and co-study leader. "Our optimized heat exchanger has about 20 times higher volumetric power density than a current state-of-the-art commercial tube-in-tube device."
Journal Reference:
Hyunkyu Moon, Davis J. McGregor, Nenad Miljkovic, et al. Ultra-power-dense heat exchanger development through genetic algorithm design and additive manufacturing (DOI: 10.1016/j.joule.2021.08.004)
(Score: 0, Offtopic) by Anonymous Coward on Monday September 13 2021, @01:23PM (2 children)
...thanks for the tech.
Sure to find a use in our full flow rocket engines.
(Score: -1, Offtopic) by Anonymous Coward on Monday September 13 2021, @01:29PM
Was lucky enough to get the nickel tour of the SpaceX Hawthorne plant, about 5 years ago. Along side the main aisle was a room with several metal 3D printers, it was explained that these were too heavy for lifting to space, so the goal was to make machines with similar capability, but much lower mass...
(Score: 0) by Anonymous Coward on Tuesday September 14 2021, @12:51PM
How the fuck is this off topic?
It is totally ON topic since Elon uses 3D tech in rocket fabrication and one of the areas needing efficiency is heat exchange in Full Flow rocket engine design.
Fuck the moderation system here.
(Score: 1, Interesting) by Anonymous Coward on Monday September 13 2021, @01:25PM (7 children)
It may be more efficient to 3D print shapes with fins or fingers inside heat exchanges. But, one little leak (a missing "pixel" in the printing process) and the whole thing is junk. Unless the leak happens to be external, it won't be repairable either.
Is 3D printing error free? (I don't know that answer).
(Score: 4, Insightful) by HiThere on Monday September 13 2021, @01:51PM (4 children)
Nothing is error free. The question to ask is "How low can the error rate be made?". But it's a good point.
I've no idea how low the error rate would need to be for this to be practical, but there are clearly places where a "single pixel" error wouldn't have severe effects. E.g. in the middle of the fins a pixel error wouldn't cause a leak, but might cause increased turbulence, and possibly not be significant. I doubt that the tube walls are one atom thick, so a single pixel error there would only slightly weaken the walls. And even a microscopic hole wouldn't be significant in many uses. Water has enough surface tension that it won't easily flow through a really small hole, or you could fill the hole with silicon wax.
Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.
(Score: 2) by FatPhil on Monday September 13 2021, @01:53PM
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 0) by Anonymous Coward on Monday September 13 2021, @09:01PM (2 children)
> Nothing is error free.
Actually, your sentence *is* error free, but incorrect.
Nothing of any significant complexity is error free.
ftfy
(Score: 2) by HiThere on Tuesday September 14 2021, @12:56AM (1 child)
But by being in error, it is correct.
Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.
(Score: 0) by Anonymous Coward on Tuesday September 14 2021, @04:12AM
And therefore wrong.
(Score: 2) by looorg on Monday September 13 2021, @02:31PM
I don't think I have ever encountered something being error free. But there are a lot of different printers and processes and materials so there are a lot of combinations. It also matters greatly then how the model or item being printed is made up, is it a solid object or is a mesh or some kind. If it's more or less solid then things are probably going to be ok I would say, a missing "pixel" (whatever that is) shouldn't be an issue. Nothing is, usually, really going to be "single pixel" thin anyway. But I guess there could be a missing or bad segment printed somewhere that creates a weak spot, or if you will a spot for future failures. If it's some kind of mesh with holes or empty spaces inside it then I guess it could be more of an issue. Is the object using filler material that later gets washed away or is it printed that way from the start etc. There could be structural issues then as you print it. But it also comes down to material choice and the process, how much cooling is there in the printing process is it plastic (of some kind) or metal (of some kind).
Perhaps a bigger issue is that a lot of printed stuff is not very smooth but has a sort of texture to it. You can fix that one the outside but if you have gaps and empty spaces inside it might become more of an issue. Plus it looks fugly.
That said if it's fast and cheap to print you just print a replacement if it was deemed faulty and hope the next one is better. If the issue keeps repeating you start looking at the model and try and fix the issue. Unless it was somehow a vital part and it's failure just created some unfortunate cascade of events and things went boom. Extreme heat in that regard makes it sound like a possibility.
(Score: 0) by Anonymous Coward on Tuesday September 14 2021, @04:14AM
> a missing "pixel" in the printing process
And also, they do not explain in the article, what would happen if a frozen chicken were to be introduced into the heat exchanger at say, Mach 2 or higher.
(Score: 0) by Anonymous Coward on Monday September 13 2021, @01:39PM (6 children)
(Score: 3, Insightful) by FatPhil on Monday September 13 2021, @01:51PM (4 children)
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 0) by Anonymous Coward on Monday September 13 2021, @02:24PM
Tube in tube is likely the best solution for high pressures -- since tubes are structurally good for holding pressure (hoop stress and all that...long forgotten from a structures class).
(Score: 0) by Anonymous Coward on Monday September 13 2021, @02:25PM
Never been in a chemistry lab? The standard "condenser" when distilling something is a glass tube-in-a-tube heat exchanger. Efficiency is shit, but nobody cares because you are usually just running tap water through the outer tube to cool the distillate.
(Score: 2) by Sourcery42 on Monday September 13 2021, @04:14PM (1 child)
I too would like to see that comparison. I'm not sure about fabrication, but the diagram shown in TFA looks very difficult to effectively mechanically clean. Chemical cleaning can work, but usually there's diminishing returns there and eventually you have to take the heat exchanger apart and clean it. Plate frame exchangers are also incredibly compact and efficient. Plus plate packs can be taken apart, washed down, and squeezed back together with fresh gaskets. This tube-in-tube thing looks more like a very elegant throwaway solution for very clean, and possibly hazardous, services. Industry already has those too https://www.alfalaval.com/products/heat-transfer/plate-heat-exchangers/Welded-plate-and-shell-heat-exchangers/packinox/. [alfalaval.com]
More options is great. Especially if this can make a throwaway exchanger relatively cheaper. I just can't tell from the article if this is quite as novel and innovative as they claim it is. Could just be a squirrel in the room.
(Score: 2) by Runaway1956 on Monday September 13 2021, @07:41PM
That was my very first thought as I read the article. These things had better be cheap enough that you can just replace them routinely. Cleaning chemically should be no different than cleaning a standard tube-in-tube. Hook up some kind of water circulation pump, add acid or alkali to the reservoir, and let it run for however many hours. Rinse, hook up the plumbing again, and return to service. If the chemical cleaning doesn't do the job, you're kinda screwed. Ultrasonic cleaning might work if you have large enough a tank to immerse your heat exchanger, but you're not going to use standard drill driven brushes inside of these tubes.
To be fair and honest, a good water treatment process extends the life of heat exchangers by orders of magnitude. Most of those that I have cleaned were destroyed by impure water with inadequate if any treatment. We expected to clean them between 5 and 7 years of service using city water, but a proper water treatment actually started auto-cleaning exchangers that were already partially blocked with lime and scale. That, and sacrificial anodes, which for some reason, our management thought were too expensive to replace.
(Score: 1, Informative) by Anonymous Coward on Monday September 13 2021, @03:38PM
"the researchers designed fins (only made possible using metal 3D printing) internal to the tubes."
Making fins is not difficult. You can easily extrude aluminum or copper pipe with fins and fit this structure in a tube shell (extruded stainless steel is another matter). Some tube in tube heat exchangers use a corrugated internal pipe to increase surface area.