5 ms·

Modern jet engine turbines: each blade a single crystal (2015)

77 points by whycome 5mo ago

gabrielsroka 5mo ago
Veritasium https://youtu.be/QtxVdC7pBQM https://youtu.be/QtxVdC7pBQM
- rramadass 5mo ago
  Titled The Ridiculous Engineering of Jet Engines, this is what everybody should watch first; Veritasium did an excellent job here. I watched it when it came out and i still am mind-blown with how Physics and Manufacturing Technology come together via "Materials Science" (https://en.wikipedia.org/wiki/Materials_science https://en.wikipedia.org/wiki/Materials_science) to create unimaginable things. This is what enables and sustains our modern world. PS: Anybody studying/working in Materials Science please recommend some books/papers for study.
  - tim333 5mo ago
    I remember back when I was in university a long while ago all the PhDs had fees except for material science where you could get paid to do one because there was so much demand for the research.
    - rramadass 5mo ago
      Right. Long ago, i had read an interview with an Indian Scientist where he stated that all of civilization's progress were only enabled by progressions in Materials Science ! (which is basically an inter-disciplinary field involving all hard sciences and engineering). The "Scientific Revolution" was merely identifying the underlying principles and systematizing them into Theories and Models. He also mentioned that the future belongs to those countries who master Materials Science since it also implies the mastery of the underlying principles. When you think about it; Mankind was playing with different materials, inventing new ones using various combinations etc. before having any scientific idea of the elements constituting them (eg. the periodic table) or the molecular structure of the gross object which was responsible for its characteristic properties etc. Successes were passed down via tradition from master to apprentice and when a single generation failed (due to disinterest/death/etc.) the whole accumulated knowledge corpus was lost. With the scientific revolution we commoditized the principles and with the industrial revolution we commoditized the technology thus accelerating everything and leading us to where we are today.
Animats 5mo ago
(2015) "With recent decreases in the price of natural gas..."
- chasil 5mo ago
  https://www.macrotrends.net/2478/natural-gas-prices-historical-chart https://www.macrotrends.net/2478/natural-gas-prices-historic...
- ars 5mo ago
  Natural gas in the US is so cheap, producers have to pay to get rid of it. However there's not enough transport hubs in the US to export it to places that needed it, although several companies have recently announced a pivot from wind energy to natural gas ports. (Wish they'd do both.)
  - leonidasrup 5mo ago
    There are many places in US where oil and gas are producted simultaneously (you can not get one without the other). High oil prices stimulate investments in oil exploration and this causes also increased natural gas production. Then if LNG export infrastructure is insuffcient natural gas prices can get into negative region. "An important feature of tight oil is that both oil and natural gas are present in the same formations and are produced from the same wells." https://www.ucs.org/sites/default/files/attach/2016/05/The-Truth-about-Tight-Oil-fact-sheet.pdf https://www.ucs.org/sites/default/files/attach/2016/05/The-T...
amelius 5mo ago
Lots of trade secrets there. I wonder how many of them the BigAI companies have already collected.
- jabl 5mo ago
  Can you name a specific example of a trade secret revealed in the article?
  - class3shock 5mo ago
    I thought they meant it as "lots of trade secrets in the jet engine field" not "lots of trade secrets in the article".
- class3shock 5mo ago
  Considering most of those trade secrets are sitting in peoples heads or in documentation behind walls AI companies have yet to get over, not many.
  - deleted 5mo ago
    [deleted]
  - etiam 5mo ago
    I think the issue would be mainly that people fail to realize the nature of what they're corresponding with, and take things from inside their heads and behind the walls, and put them into the chat? I hope you're right though.
    - class3shock 5mo ago
      No one is "corresponding" trade secrets outside of their company. I recommend reading up on ITAR and the resulting culture it has created around aerospace info.
      - foobar10000 5mo ago
paozac 5mo ago
A good article on jet engines: https://www.construction-physics.com/p/why-its-so-hard-to-build-a-jet-engine https://www.construction-physics.com/p/why-its-so-hard-to-bu...
sudb 5mo ago
I've always found the pigtail selector to be the coolest part of the process which just uses geometry to "select" a crystal that grows in the correct orientation for the turbine blade.
3eb7988a1663 5mo ago
Efficiency was mentioned a few times, but without any hard numbers. What was the state of the art efficiency over time from a 1940s design to today? Have improvements plateaued or is there still a lot of theoretical gains on the table?
- icegreentea2 5mo ago
  This might be interesting: https://www.nationalacademies.org/read/23490/chapter/6 https://www.nationalacademies.org/read/23490/chapter/6 Thermodynamic efficiency (which is what turbine blades enable) has increased from ~30 to 55% over the last 50-60 years. The book estimates that the practical limit of for thermodynamic efficiency is in the 65-70% range.
  - 3eb7988a1663 5mo ago
    Great resource, thanks.
  - heavenlyblue 5mo ago
    Is there a curve for how much an efficiency gain translate in max distance?
    - icegreentea2 5mo ago
      From https://web.mit.edu/16.unified/www/FALL/thermodynamics/notes/node98.html https://web.mit.edu/16.unified/www/FALL/thermodynamics/notes... All other things equal, range varies proportionately with efficiency. Ie, if you have 500km range at 50% overall efficiency, then at 65% overall efficiency, you have 650km range.
- deleted 5mo ago
  [deleted]
leonidasrup 5mo ago
Asianometry Gas Turbine Blades and their Heat-Defying Single-Crystal Superalloys (video) https://www.youtube.com/watch?v=yR5mR-KoNzA https://www.youtube.com/watch?v=yR5mR-KoNzA
CWwdcdk7h 5mo ago
I suggest https://www.youtube.com/watch?v=wbXbj20351o https://www.youtube.com/watch?v=wbXbj20351o as suplementarny material.
tim333 5mo ago
Apparently turbine blade production is backlogged five years now and a bottleneck on AI data center production because the proposed data centers need more power than the current grid provides so people are trying to use gas turbines to power them but there are only a few places that make the blades. Boom, the YC backed supersonic plane lot are trying to make their own blades/engines to cash in on the AI rush which should be interesting. They are a bit vague on how they are doing it: >Q: What engine parts are you printing for Symphony?...High-Pressure Turbine (HPT) Blades: These blades spin at extremely high speeds, extracting energy from the hot gases >While these additively-manufactured components won’t fly on the final Symphony engine, they are fully operational and critical to validating the core architecture. On Symphony, these parts will be replaced by ones made from more traditional manufacturing methods. So I guess 3D printing the prototype? Dunno if they are going to make their own wax casting plant like in the Veritasium video? https://boomsupersonic.com/flyby/turning-powder-into-power-how-boom-is-using-3d-printing-to-accelerate-symphony-engine-testing https://boomsupersonic.com/flyby/turning-powder-into-power-h...

77 points by whycome 5mo ago

gabrielsroka 5mo ago

Veritasium https://youtu.be/QtxVdC7pBQM https://youtu.be/QtxVdC7pBQM

rramadass 5mo ago
Titled The Ridiculous Engineering of Jet Engines, this is what everybody should watch first; Veritasium did an excellent job here. I watched it when it came out and i still am mind-blown with how Physics and Manufacturing Technology come together via "Materials Science" (https://en.wikipedia.org/wiki/Materials_science https://en.wikipedia.org/wiki/Materials_science) to create unimaginable things. This is what enables and sustains our modern world. PS: Anybody studying/working in Materials Science please recommend some books/papers for study.
- tim333 5mo ago
  I remember back when I was in university a long while ago all the PhDs had fees except for material science where you could get paid to do one because there was so much demand for the research.
  - rramadass 5mo ago
    Right. Long ago, i had read an interview with an Indian Scientist where he stated that all of civilization's progress were only enabled by progressions in Materials Science ! (which is basically an inter-disciplinary field involving all hard sciences and engineering). The "Scientific Revolution" was merely identifying the underlying principles and systematizing them into Theories and Models. He also mentioned that the future belongs to those countries who master Materials Science since it also implies the mastery of the underlying principles. When you think about it; Mankind was playing with different materials, inventing new ones using various combinations etc. before having any scientific idea of the elements constituting them (eg. the periodic table) or the molecular structure of the gross object which was responsible for its characteristic properties etc. Successes were passed down via tradition from master to apprentice and when a single generation failed (due to disinterest/death/etc.) the whole accumulated knowledge corpus was lost. With the scientific revolution we commoditized the principles and with the industrial revolution we commoditized the technology thus accelerating everything and leading us to where we are today.

Animats 5mo ago

(2015) "With recent decreases in the price of natural gas..."

chasil 5mo ago
https://www.macrotrends.net/2478/natural-gas-prices-historical-chart https://www.macrotrends.net/2478/natural-gas-prices-historic...
ars 5mo ago
Natural gas in the US is so cheap, producers have to pay to get rid of it. However there's not enough transport hubs in the US to export it to places that needed it, although several companies have recently announced a pivot from wind energy to natural gas ports. (Wish they'd do both.)
- leonidasrup 5mo ago
  There are many places in US where oil and gas are producted simultaneously (you can not get one without the other). High oil prices stimulate investments in oil exploration and this causes also increased natural gas production. Then if LNG export infrastructure is insuffcient natural gas prices can get into negative region. "An important feature of tight oil is that both oil and natural gas are present in the same formations and are produced from the same wells." https://www.ucs.org/sites/default/files/attach/2016/05/The-Truth-about-Tight-Oil-fact-sheet.pdf https://www.ucs.org/sites/default/files/attach/2016/05/The-T...

amelius 5mo ago

Lots of trade secrets there. I wonder how many of them the BigAI companies have already collected.

jabl 5mo ago
Can you name a specific example of a trade secret revealed in the article?
- class3shock 5mo ago
  I thought they meant it as "lots of trade secrets in the jet engine field" not "lots of trade secrets in the article".
class3shock 5mo ago
Considering most of those trade secrets are sitting in peoples heads or in documentation behind walls AI companies have yet to get over, not many.
- deleted 5mo ago
  [deleted]
- etiam 5mo ago
  I think the issue would be mainly that people fail to realize the nature of what they're corresponding with, and take things from inside their heads and behind the walls, and put them into the chat? I hope you're right though.
  - class3shock 5mo ago
    No one is "corresponding" trade secrets outside of their company. I recommend reading up on ITAR and the resulting culture it has created around aerospace info.
    - foobar10000 5mo ago

paozac 5mo ago

A good article on jet engines: https://www.construction-physics.com/p/why-its-so-hard-to-build-a-jet-engine https://www.construction-physics.com/p/why-its-so-hard-to-bu...

sudb 5mo ago

I've always found the pigtail selector to be the coolest part of the process which just uses geometry to "select" a crystal that grows in the correct orientation for the turbine blade.

3eb7988a1663 5mo ago

Efficiency was mentioned a few times, but without any hard numbers. What was the state of the art efficiency over time from a 1940s design to today? Have improvements plateaued or is there still a lot of theoretical gains on the table?

icegreentea2 5mo ago
This might be interesting: https://www.nationalacademies.org/read/23490/chapter/6 https://www.nationalacademies.org/read/23490/chapter/6 Thermodynamic efficiency (which is what turbine blades enable) has increased from ~30 to 55% over the last 50-60 years. The book estimates that the practical limit of for thermodynamic efficiency is in the 65-70% range.
- 3eb7988a1663 5mo ago
  Great resource, thanks.
- heavenlyblue 5mo ago
  Is there a curve for how much an efficiency gain translate in max distance?
  - icegreentea2 5mo ago
    From https://web.mit.edu/16.unified/www/FALL/thermodynamics/notes/node98.html https://web.mit.edu/16.unified/www/FALL/thermodynamics/notes... All other things equal, range varies proportionately with efficiency. Ie, if you have 500km range at 50% overall efficiency, then at 65% overall efficiency, you have 650km range.
deleted 5mo ago
[deleted]

leonidasrup 5mo ago

Asianometry Gas Turbine Blades and their Heat-Defying Single-Crystal Superalloys (video) https://www.youtube.com/watch?v=yR5mR-KoNzA https://www.youtube.com/watch?v=yR5mR-KoNzA

CWwdcdk7h 5mo ago

I suggest https://www.youtube.com/watch?v=wbXbj20351o https://www.youtube.com/watch?v=wbXbj20351o as suplementarny material.

tim333 5mo ago

Apparently turbine blade production is backlogged five years now and a bottleneck on AI data center production because the proposed data centers need more power than the current grid provides so people are trying to use gas turbines to power them but there are only a few places that make the blades. Boom, the YC backed supersonic plane lot are trying to make their own blades/engines to cash in on the AI rush which should be interesting. They are a bit vague on how they are doing it: >Q: What engine parts are you printing for Symphony?...High-Pressure Turbine (HPT) Blades: These blades spin at extremely high speeds, extracting energy from the hot gases >While these additively-manufactured components won’t fly on the final Symphony engine, they are fully operational and critical to validating the core architecture. On Symphony, these parts will be replaced by ones made from more traditional manufacturing methods. So I guess 3D printing the prototype? Dunno if they are going to make their own wax casting plant like in the Veritasium video? https://boomsupersonic.com/flyby/turning-powder-into-power-how-boom-is-using-3d-printing-to-accelerate-symphony-engine-testing https://boomsupersonic.com/flyby/turning-powder-into-power-h...