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This was honestly a pretty poor choice of model to demonstrate their 3D printing capability. While it looks cool, the designer clearly does not know much about the design of rocket engines or fluid dynamics in general, and worse, this model doesn't really make it clear what they're capable of in terms of say minimum wall thickness or maximum unsupported span, surface finish, processing time, etc. Nothing here seems particularly impressive from anything other than an aesthetic standpoint.

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.



I'll add on that Aerospike engines tend to be popular with non-Aerospace engineers because they look cool. In reality Aerospike engines are optimizing for a design parameter space that doesn't need optimization. To draw an analogy to coding, it's like optimizing code in the non-crtical path. It doesn't really help you.

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 don't think that's correct. It appears that this was designed using topology optimization.

https://en.wikipedia.org/wiki/Topology_optimization


It's just a fanciful advertisement. It's not even much of a demo, for the reasons given by OC. They said it wouldn't work in real life.




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