We just built the world’s largest 3D-printed aerospike rocket engine
hyperganic.com
hyperganic.com
Further, it seems they're trying to make parametric CAD, the industry standard for the past 30 years, sound impressive to the layperson using buzzwords.
Rocket engine bells expand high pressure subsonic choked flow into supersonic low pressure flow. They are designed to do that most optimally for a given external pressure (if you try to expand the gas to a lower pressure than the atmospheric pressure then vibrations begin and can tear an engine apart because of flow backwards into the engine bell). Aerospike engines, if designed correctly, work by automatically optimizing to always expand the gas to whatever the atmospheric pressure is, maximizing total specific impulse over the flight. However they tend to have problems with cooling and so tend to be extremely heavy compared to other engine designs and you can equivalently design for this space by instead using multiple rocket stages, which all rockets do. More so, if you're trying to re-use rockets as is the current trend, having a heavy engine makes even less sense as you need to land that heavier engine.
Aerospike engine research made sense when it was the current fad to design single-stage-to-orbit rocket designs because they thought that re-using multiple stage vehicles wasn't possible. However that's no longer the case. Aerospike engines are a technological dead end.
Disclaimer: I am not an aerospace engineer, though I did take a couple of aerospace engineering courses before switching my major (turns out I wasn't great at the type of math needed) and I have a strong interest in the field and have talked to people in the field (and former classmates/labmates who are aerospace engineers).
I’m sure its cool they’ve been able to design and 3D print a complex structure - however, the company blog appears to only link to additive manufacturing companies: I couldn’t find a subsequent link where this engine has been (even) ground tested, demonstrating basic validation of the design in test / fire conditions: till that happens, this is just (imo) a cool looking untested, unvalidated design and therefore, untested, unvalidated algorithmic design..
None of the reports covering this even mention any testing, or any anticipated testing. Is it an art piece?
This is apparently a demonstration of their geometry software, not something that will ever be fired, since they are an "organic" modeling company, not a rocket company.
How can one make any functional claims of value without some functional testing? What am I missing?
We don't know if they sold the design and whether it was tested. The design itself is very interesting - in particular the complex heat exchange structures.
On it being optimal, or even more efficient, as long as it's cheaper to build than a conventional engine, it's game.
It is like a computer displaying "hello world". The output isn't particularly exciting, I could do better with an index card.
However, the fact that the a computer could take a set of inputs and display something at all shows exciting promise. The same is true here.
For a real engine design, you would have to work extensively on the inputs, boundaries, and goals. The impressive part is that this software can handle this complex of a parameter set at all.
indeed, since it does't need to do anything but look cool, the inputs could be "weirdness factor" and "excessive internal wall ratio" and nothing else, and they thought "this kinda looks like an aerospike"
This is exactly why I am impressed. I have some basic understanding of rocket engine and aerospike design, and can recognize most of the features and the functions they would serve in this design. I have no clue how optimal they are, but it is clear that they are taking function into consideration.
Moving from the outside of the engine in, you can see that support lattice has been added to the exterior and density adjusted on the exterior to reenforce high stress areas.
Next, the coolant jacket around the combustion chambers has has baffles (verticals s curves) that seem to adjust cooling in specific areas.
It looks like the spike cooling system (the dense horizontal lines) is trying to balance fluid resistance with how much the cryogenic oxygen.
The one part I don't understand is what the Y shaped channels in the very center are supposed to do. This is the liquid oxygen flow to the tip of the spike before it returns along the outside of the spike as a heat exchanger (mentioned above). It looks like some sort of expansion chamber but I would have to ask a professional aerospike engineer what it is for.
This is a long way of saying the structures show functional intent to converge on some solution. Some parts seems random, but most algorithmic design is random change and iterative testing; Essentially evolutionary code, where permutations are made, compared, killed off, then fed into future models. I wonder how they handle so many degrees of freedom, and how much of what we see in the output was pre-defined.
yeah, it has a racing stripe, and fins, like some stuff which goes fast also has, but that doesn't mean that adding it to a power plant makes the power plant fast
as another engineer that's worked in aerospace, none of those functional design aspects seem to be actually performing a function here other than "we saw this on something weird looking", as in not enough evidence that there's functional intent converging on something functional
Looking at their website, they are simply developing a tool for more integrated algorithms from the park level to system level.
With this in mind, the the component integration of the model itself is extremely impressive and a proof of concept. It doesn't matter if it actually works or not, that's not really the point.
It's fine not to actually test fire it, but in that case prove it with simulations. Demonstrate that it's superior to existing designs, or at the very least that it's functional.
The article asks really tough questions of itself, like "Have you tested it, does it work?" and then very carefully does not say yes or no. Why ask yourself those questions if you don't want to answer them?
Imagine a politician who starts a campaign speech "People are asking me, 'Am I a Ghost Wizard?' and here's my answer: ghost wizards are valid concerns. This builds upon the latest in crytozoological knowledge of supernatural studies. The first study of such wizards was conducted in the 1960s and 1970s. As I've discussed previously with my constituents, the United Nations has previously looked into ghost wizards. In a way, it seems that..."
Where's the built engine? All I see in TFA is an individual complex 3d-printed component, seemingly just cutaway versions at that. Not a built engine.
1. a machine that converts power into motion.
By definition of the word, they didn't print an engine. It's an art piece.
Failure modes from any defect would of course depend on the scale and type of the defect, and could lead to nothing or catastrophic failure
Appears to me to be littered with waveguides upon waveguides, pinch points, and various irises. This is really cool. Whether it works to cool the nozzle down, I feel like the beginning simulations could easily yield do more of this, less of that, test, and vary in a iterative feedback loop of sorts. Maybe even hot gas at tight-knit control, induction loops for moving heat inward to segments, or outward? Think of just how fast you could build this just by going single-part alone if it works.
I guess I should preempt a couple of the most common responses I get to this view:
First, markets provide first mover advantage even without intellectual property restrictions. The idea that governments should provide monopoly protections on ideas is anti-competetive and anti free market. Libertarians at places like the Mises institute recognize this and have some good talks on the subject.
Also, we would not see investment dry up without IP restrictions. We would see the nature of investment change from fewer larger investments to more smaller investments as competitors race to get the latest incremental improvement to market first by seeking investment to upgrade production lines, etc.
Workers absolutely deserve to be compensated for their work, but we see that in most IP restriction regimes, businesses take all the winnings and pay only wages to the workers doing the inventing. Individual inventors can still have first mover advantage, and I would argue that most new invention is not motivated by profit but curiosity. Removing IP restrictions would vastly increase invention by curiosity, as there would be far more places where a curious engineer could tinker and improve something. Imagine that one person invents something and gets a patent. This will prevent 100 other people from tinkering and improving upon it. This is why I say that the sole function of a patent is to reduce innovation - because that is the one literal function of them. The supposed follow on effects are more of a cultural meme that are often disproved by things like the open source movement, which clearly demonstrates that a lot of the assumptions around IP restrictions are not strictly true.
Finally, people in foreign countries who cannot afford expensive machines like medical scanners etc still deserve to build copies of those machines for their own use, but patent harmonization laws like TRIPS prevent these sorts of things. The same goes with medicine.
https://en.m.wikipedia.org/wiki/Aerospike_engine
Does anyone know how this design solves the problem?
>The world’s biggest 3d-printed rocket engine was printed by the AMCM M4K customized machine.
I hope some of this tech comes into the consumer price range with little or no post processing involved
Does it work?
It's entirely possible that this aerospike engine is actually lighter because they don't need large nozzles and nozzle extensions and are more efficient