I shortened the title a bit from "LEAP 71 hot-fires 3D-printed liquid-fuel rocket engine designed through Noyron Computational Model."
From the article:
- First rocket engine built entirely through a computational model without human intervention
- Likely the shortest time from spec to manufacturing for a new rocket engine (2 weeks, usually this process takes many months in manual engineering using CAD)
- First liquid fueled rocket engine developed in the United Arab Emirates
> Likely the shortest time from spec to manufacturing for a new rocket engine (2 weeks, usually this process takes many months in manual engineering using CAD)
Does anyone in the field of rocketry specifically know if this alleviates some previously annoying constraint?
My uninformed gut suspects that these rocket spend an overwhelming amount of time in the post-design stage (I mean rocket engines seem to stick around for a long, long time, right?). But I’m a programmer I don’t know anything about this stuff.
Exactly, right, I don’t trust my intuition here because that’s seen as an absurdly long time in software, whereas in rockets it seems like months and weeks just kinda zoom by.
"We've built a great new way to design physical structures."
"So what? The existing ways work just fine."
"We designed and built a rocket engine in two days."
However, even in the rocket field, there's a "design, simulate, build, test" cycle. They can do two of those steps in effectively 0 time and with significantly lower cost.
Moreover, it looks like the design has incremental feedback from something akin to simulate.
One might argue that CAD is "computer-aided human design" whereas this engine was designed using "human-aided computer design". That is, the computer isn't aiding in the design, the computer is the designer (and I assume humans are just providing some basic constraints). The difference between the two is subjective and perhaps meaningless, but it does poetically describe the technological advancements that are being made in physical design.
That being said, I think stuff like this is governed by homeostasis: bleeding-edge technological advancements eventually get turned into regular features. In this case: I'm sure we'll continue to see CAD software to build more complex structures with less human intervention; and maybe eventually designers will expect their CAD software to generate whatever rocket engine their product requires.
I was going to say that this is nothing Hyperganic hasn't done....and then looked up Lin and Joesefine who were previously at....Hyperganic. I wonder what the story is over there. Open sourcing their geometry kernel is a very confident move.
Interested to see what happens between Lab71, Hyperganic and nTopology - traditional CAD/CAM packages are integrating topology optimisation / generative design but are simply not voxel-first. Perhaps there's a middle-ground to be found (though possibly requires more developed use cases first).
>The engine was designed autonomously without human intervention
Hmmm. My software compiles itself 'without human intervention' when I click the compile button (ignoring the thousands of hours of work I put into writing the code and the even larger amount of work that went into creating the compiler).
This appears to be a pressure-fed rather than pumped engine, so limited real-world utility. Nonetheless, it’s incredibly impressive especially given that it seems to have been successful on the first try.
I wonder how practical it might be to integrate turbo machinery into an automated design system like this?
Oh, and it really is beautiful with copper construction and that fascinating swirl.
> This appears to be a pressure-fed rather than pumped engine, so limited real-world utility
This is addressed in the article:
> This is a relatively compact engine, which would be suitable for a final kick stage of an orbital rocket.
It has lots of real world application, just not currently as part of a lift stage since you're right it's a pressure based one as opposed to a pumped engine.
All are pressure fed. A pump generates pressure. It's common to test engine components without pumps using high pressure vessels in lieu of pumps. The E Complex at Stennis Space Center specializes in this approach.
Pressure fed is a fixed term when applied to rocket engines and means “fed only by the pressure in the tank (which is most of the time generated by having a pressurization system fed by another high pressure helium tank) and not by a pump”.
“ The engine uses thin cooling channels that swirl around the chamber jacket, with a variable cross sections as thin as 0.8mm. The Kerosene is pressed through the channels to cool the engine and prevent it from melting.”
Kerosine/LOX burns very bright, compared to the Methane/LOX tests you may have seen in other tests, which produce almost invisible exhaust and have bright shock diamonds. Unfortunately the cameras were calibrated for the less-bright tests they usually do on this test stand, so the footage is overexposed. We tried to stop down the cameras, for the long duration run, but it was still too bright. So no pretty shock diamonds in the footage. Exhaust is supersonic after engine throat, reaching around 2300m/s at nozzle exit.
If your blowtorch produces 5kN, all the power to you. Even small rocket engines are surprisingly strong.
Lin (co-founder of LEAP 71 — and "I was there, when we heard the rocket rumble through 3m of concrete bunker walls")
Yeah, no pretty looking shock diamonds in that exhaust. Which makes me thing the exhaust velocity is pretty low, which I'm not too surprised by since the throat of that engine looks pretty large. And the specific impulse (efficiency) of a rocket engine is directly tied to the effective exhaust velocity [0].
Still amazingly cool, but to the other questions on this thread I'm sure the performance is not comparable to an existing rocket engine design.
An incredible achievement and in to my eyes a thing of beauty. This is not the first time I've seen computational geometry (played with it myself) but this output seems something else.
Is "engine" appropriate to use here? It seems to just be the combustion chamber, similar to the article last week about the rocket test in India. It's cool research, but I don't know that the engine process matters much when you compare this to what SpaceX is doing with their engines and reducing the complexity of the moving parts, not just the static ones.
While the terms can change over time, my understanding in ME circles is that "engine" is usually referring something that converts a source of energy into a force. So in this case, a device is using chemical energy (LOX + kerosene) into thrush (5kN) so it would meet the definition of an "engine."
Err... almost. An engine is something that has significant engineering effort put into it, you can see that the words are cognate. A motor is (usually an engine) that converts potential (stored) energy into motion, by way of some force. I do believe that motor and motion are also cognate.
But outside the etymologies, there is no standard, agreed upon definition for either the term engine nor motor. I personally like these etymology-based definitions (otherwise how do you excuse the term "siege engine") but it's not a hill I'd die on.
On contrair el capitan: It is trained on human designs and design processes. It has knowledge on physics and flow mechanics + propulsion simulations baked into it. It should outcompete a human, who gains that intuition by try and terror.
I imagine the factories of the future will be 3d printed and look like metallic fungus. They will be serviceable only with robots that can slide around in narrow gaps to inspect them. They will mostly be operated in the dark. Perhaps they will be operated deep underground.
They are both about 3d printing rocket engines, but it's a bit of comparing apples and oranges.
- The linked article is about improving the speed of manufacturing with 3D printing. The linked article claimed that there was no need for any post-fabrication qualification and there was much skepticism in that claim. But they did perform a sub-orbital launch.
- This article is about improving speed in the design cycle. The article mentions after printing it was "post-processed at the University of Sheffield and prepared for the test". Here there is skepticism of the actual performance (namely efficiency) of the engine for practical purposes.
3D printing rocket engines themselves in and of itself is not a new thing. Rocket Labs has 3D printed rocket engines and has been flying them since 2018
You could almost certainly source a cylindrical body to pour the cast into for cheaper and easier than 3D printing one - of almost any dimension. The tricky part is in the coring shape (for thrust profile), not the shape of the cylinder.
That said, 3D printing an easily-removable mold for coring, such as from wax, would be amazing.
There are 3d-printers (and fairly cheap toolheads) that can handle ceramics, i.e. clay. Resolution isn't anywhere near as good as PLA, so in practice people often print a mold to make the mold from, but it's an option.
I think long term there is no reason for Electrochemical Additive Manufacturing (ECAM) to stay expensive as it uses TFT display technology which is mature and electroplating solution is widely available. Maybe patents will keep it expensive.
It builds on normal electroplating which is already a safe DIY activity, best not do drink it though.
This is selective electroplating by only applying electric current to pixel sized areas and building up the object layer by layer like a resin printer. It's truly amazing what it can do. It's just really new.
Awesome demonstration of an exciting development technique. It's still proof of concept level at 5kN thrust. For comparison, the current Falcon 9 engine (Merlin 1D Vacuum+) has 981 kN thrust.
And just to put those numbers further in perspective: the current design goal of the SpaceX Raptor engine is 3MN (3000kN). Currently they have achieved 2.64MN during ground testing. It is speculated that each of the 33 engines of the superheavy booster during testflight 4 were configured for a thrust of approx 2MN.
Obviously the Raptors are much, much larger than the 3D printed engine from the article.
If they had asked the computer to design them a 981kN thrust engine they might have needed to be a little more cautious about lighting it up on a test stand. 5kN seems plenty for a first proof of concept.
I completely agree, just pointing out that it is at the PoC stage right now. Scaling up will be exciting. I hope the methods work as well for 1000 kN as they do for 5 kN. This will be awesome if it works at scale. I have been looking forward to engineering like this since a Ted talk I saw about "evolving" designs based on user feedback.
Bonus points for "steely-eyed rocket-woman" although it looks like rocket engines are "just" an example/test-case, which makes it even more impressive.
From the article:
- First rocket engine built entirely through a computational model without human intervention
- Likely the shortest time from spec to manufacturing for a new rocket engine (2 weeks, usually this process takes many months in manual engineering using CAD)
- First liquid fueled rocket engine developed in the United Arab Emirates
- Engine worked on the first attempt
- No CAD was used in the design