gabrielsroka3 days ago
Veritasium https://youtu.be/QtxVdC7pBQM
rramadass2 days 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) 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.
tim3332 days 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.
rramadass2 days 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.
leonidasrup2 days ago
Asianometry
Gas Turbine Blades and their Heat-Defying Single-Crystal Superalloys (video)
sudb3 days 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.
tim3332 days 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-h...
3eb7988a16633 days 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?
icegreentea23 days ago
This might be interesting: 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.
3eb7988a16632 days ago
Great resource, thanks.
heavenlyblue2 days ago
Is there a curve for how much an efficiency gain translate in max distance?
icegreentea22 days ago
From 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.
CWwdcdk7h2 days ago
I suggest https://www.youtube.com/watch?v=wbXbj20351o as suplementarny material.
paozac3 days ago
A good article on jet engines: https://www.construction-physics.com/p/why-its-so-hard-to-bu...
Animats3 days ago
(2015)
"With recent decreases in the price of natural gas..."
ars3 days 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.)
leonidasrup2 days 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-T...
chasil3 days ago
amelius3 days ago
Lots of trade secrets there. I wonder how many of them the BigAI companies have already collected.
class3shock3 days 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.
etiam3 days 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.
class3shock3 days 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.
foobar100003 days ago
Note that google cloud has an itar-compatible gemini pro and google drive / docs - so, people do talk to it - and google is of course contractually obligated to not export it, nor to learn from it.
This is very different that AWS fed-gov bedrock thingie - where AWS promises that the models are running on hardware dedicated to you, with no external logging, etc.
JumpCrisscross2 days ago
> google cloud has an itar-compatible gemini pro and google drive / docs - so, people do talk to it
A lot of aerospace engineering is touch and feel. Someone has a "sense" for when to do the next step, and how to finagle the part so it comes out a particular way. They can train someone, if they apply themselves intently. But they probably couldn't explain it in words if they tried.
leonidasrup2 days ago
Don't forget these companies are both civilian and millitary contractors. These kind of information will stored in separate air-gapped computer systems.
Employes are required to have background check.
https://suppliers.rolls-royce.com/GSPWeb/ShowProperty?nodePa...
[deleted]3 days agocollapsed
trogdor3 days ago
If a company has a specific knowledge advantage regarding the design or manufacture of turbine blades, wouldn’t they patent it?
applied_heat2 days ago
Patents expire
Patents are difficult to enforce internationally
Where would coke be if the recipe was patented instead of trade secret ?
chii2 days ago
While your point is completely true, the specific example of coke is ironic because Coke's dominance is more related to marketing than their formula!
jabl3 days ago
Can you name a specific example of a trade secret revealed in the article?
class3shock3 days ago
I thought they meant it as "lots of trade secrets in the jet engine field" not "lots of trade secrets in the article".