How NASA Reinvented the Rocket Engine

[@RealEngineering]

Watch the next episode of Real Engineering 2 weeks early with this link: go.nebula.tv/realengineering

[@pyeitme508]

RAD!

[@CyFr]

That fluid flow "valve" was developed by Nicola Tesla, literally named the Tesla Valve.

[@flipnshifty]

MERGINAL GAIN

[@BS-vm5bt]

Interesting video though I prefer the NSRW or a FFR engines. They work way better if you want low relativistic speeds while chemical engines are extremely unpractical in comparison. If we want to expand in the solar system fission is the only way to go since fusion does not currently exist. The NSRW has a speed limit of 7.62% of C with 300 ton spacecraft with weapons grade uranium source. Even with efficency loss that a nuclear engine has its still way better then chemical rockets thx to its energy density. Nothing can compete with fission.

[@sahinyasar9119]

@@CyFr I was thinking same thing

[@sfoti6973]

The best April Fool's day video is a completely normal video that makes the viewer question everything the entire time.

[@ExEBoss]

Especially with a clickbaity title like that.

[@jasonmajere2165]

This is very real.

[@Eduardo_Espinoza]

Did it out 3 weeks before on nebula?

[@franklinblunt69]

Especially when reliant upon Russian technology...😁

[@andrewdoesyt7787]

@@franklinblunt69what do you mean by that?

[@treymoore6901]

I’m a minute in to this video and can’t tell if it was intentionally published on April 1 or not…

[@austinlhampton]

No very real thing, theres a couple vids out there of people making them on their own, they are super cool, watched an interview where one of the dudes mentioned that the shock waves blew off a 500lbs door to test chamber XD shits wild, ong though the air you have to force through to get the effect to make it work is insane, issue is the damn thing not melting itself

[@dennispremoli7950]

This exists.

[@InstructorRandy]

Nah it's legit man

[@laurencehoffelder1579]

@@austinlhampton i mean the "500lbs door engine" is not a DIY engine but the test engine from the TU Berlin. NEVER try to build a RD-engine DIY or operate it without a sufficient test stand. It ist just to unstable and difficult to get right for the amateur.

[@Tuned_Rockets]

it was published on nebula 2 weeks ago so april 1st is probably a coincidence

[@RahulAhire]

Saw the M1 abram tank video. Your animation have come a long way from blue graph paper design to now realistic 3D renders. I really loved it

[@fateh5914]

That’s a different channel. Real Engineering hasn’t ever made a M1 Abrams video. But his graphics have definitely improved.

[@RahulAhire]

@@fateh5914 it's on nebula

[@casualbird7671]

@@fateh5914 ..did you not watch the end of this video?

[@fateh5914]

@@casualbird7671 sorry about that, I’m wrong on this point. There is an M1 Abrams video on Nebula. I should’ve checked before posting my comment. My apologies.

[@emmanotsostrong]

@@fateh5914 why do your comments sound like they were written by ChatGPT? 🤔

[@CinemaDemocratica]

"Sir we've got a problem with explosions happening in the combustion chamber." "Have you tried setting off explosions in the combustion chamber?"

[@twistedyogert]

"I used explosions to destroy the explosions."

[@CinemaDemocratica]

@@twistedyogert I didn't remember writing my comment so this was a lot of fun for me. :-)

[@bencabot3165]

This video was really cool to watch! I work in a lab with one of the guys who designed the NASA RDE, and one of my other coworkers is cited here, it's awesome to see detonation combustors getting some more attention on KZbin!

[@patelp9701]

I also work with one of those guys!

[@Eduardo_Espinoza]

Don't lie, it was all chat GPT

[@tonyrusi1978]

Name the engineers! They deserve the credit!

[@vlad_kach_]

KZbin is the best!

[@wsafd]

​@@tonyrusi1978opsec violation

[@Penultimeat]

When you started describing the needs for the injectors, I new you were gonna mention Tesla Valves! Very cool that they have some palpable practical use case.

[@petersilva037]

disappointed he didn't call them Tesla valves.

[@hydrolifetech7911]

@@petersilva037 same here!

[@arnaudt3935]

@@petersilva037 Yep

[@vorpalinferno9711]

@@petersilva037 You cant call any tech related product 'Tesla' these days thanks to Elon. Its not that he is going to attempt copyright trolling, its the confusion the naming is going to create amongst casual audience. Nvidia had their server based GPUs called Tesla long ago before any car was named that. Jensen just withdrew the branding name to remove any confusion.

[@TheRmbomo]

@@vorpalinferno9711 You could just call them Nikola Tesla valves then. Rolls off the tongue only marginally worse, and no confusion.

[@thepilotman5378]

It's actually crazy that I watched the full version of SmarterEveryDay with the Saturn V walkaround and they spent a lot of time discussing the engine baffels and problems before hand. Stuff like this proves there is another way to do things. re-inventing the wheel is sometimes the way to go!

[@HuntingTarg]

One could say 're-engineering.' Ancient chariot wheels were redesigned for agricultural carts of the Roman and medevial periods; which were redesigned for travel wagons in the American West, which were redesigned for automobiles in the 20th century. This is simply a re-engineered rocket engine designed to use detonations in a controlled way, rather than prevent detonations.

[@MonkeyJedi99]

I think "rotating detonation engine" is one of the coolest names for a rocket ever.

[@peadarr]

Did you watch the first half of the video where he spends most of the time explaining why it wasn't possible to build one until today?

[@k6l2t]

The less bias you have, the more you will realize that the metaphorical wheel needs to be "re-invented" a lot more than you might think.

[@Eduardo_Espinoza]

@pascal jacob It was because of the 3d printing of the Tesla values right?

[@zemperus1639]

Another 3D printed, Oxide-dispersed (ODS) sintered composite alloy named GRX-810 is also developed for NASA. Very cool stuff, material engineering.

[@mpetersen6]

I think that advanced alloys or composites combined with 3D printing and proper designs concentrating on maximunstrength vs minimum weight might finally allow for a practical SSTO. Not one that carries cargo. But one that can function as a taxi carrying crew to orbit.

[@Jaker788]

​@@mpetersen6 I'm afraid the physics of SSTOS just don't ever make sense on Earth. 2 stage rockets can still be rapidly operated like a taxi and are significantly more effective and reasonable in size/weight vs carrying volume and capacity, the technology of rapid reusability and reliability just needs to be worked on as that is the biggest factor to being an effective taxi.

[@How23497]

@@mpetersen6 SSTOs from earth are just flat out inferior. Maybe from a different place, but they are just less efficient.

[@mpetersen6]

@@How23497 Lets say with breakthroughs in materials science and improvements in engine performance it was possible to build an manned SSTO capable of carrying say 6 passengers to orbit. Even if it is not as efficient as an optimized two stage vehicle. With a short turn around time. There is more than one type of efficiency. There is the mass ratio efficiency. And then there is the man hours turnaround efficiency. One thing in terms of materials science that might improve the possibility of an SSTO could be the use of Byrilium alloys in place of some of the materials in use today. And yes I'm aware of the potential issues with Byrilium. Besides say we have a barely workable SSTO capable of functioning as an orbital taxi. Just how well, would the same vehicle work from the Lunar or Martian surface. As an aside perhaps an SSTO (1) could function with dropable liquid fueled booster of extremely simple design. 1) It should be remembered that the first US built launch vehicle to place a man into orbit was almost an SSTO.

[@moritzaufenanger2537]

Coming from the bike industrie this comment made me look twice :)

[@SugarFreeEngineering]

Excellent video; I actually did my Master's research and published a paper on GRCop-42 in partnership with NASA. It's a fascinating material and has a ton of promise. We looked at 3D printing it using high-pressure cold spray deposition, bonding it with another super alloy called HR-1, and doing many experiments with various ways to heat treat them. I'd be happy to answer any questions, and link my article or video of the my presentation. Either way, this video made my day and certainly brought a smile to my face. Thanks for the great work!

[@davedsilva]

Please link your article and video.

[@EngineerPlaysTV]

i'd like to see it

[@diegoespinosa8418]

hey could you link or share the article when you have a chance

[@aXimo]

The sad part is that, engineering on Earth by humans is vastly limited by money. Everything we do, we do for money. Imagine, what could we achieve, if we were to work together for greater good and not for money.

[@clapetto]

I need to make a small correction: at 8:05 the compressor is actually the segment 2-3, as it increases pressure while reducing volume. Point 1-2 is actually a fictitious transformation used for calculation purposes from what I remember, as it's not really a cycle sincr the exhaust is not really cooled down and then reused.

[@zecc81]

I had to replay that 3 times to really make sure I was hearing "a compressor decreases the volume at constant pressure" and concluded that no, that is not how that works.

[@verylongname8161]

@@zecc81 same here, of course its a compressor why would it not increase the pressure also purely for land based electricity generation, combined cycle plants can be well over 80% efficient so its not really useful to my disappointment

[@ichbrauchmehrkaffee5785]

I was specifically looking in the comments to see if someone else stumbled upon this. Just recently wrote an exam in thermodynamics, where we did cover cyclic processes. I don't see how an isobaric reduction in volume would make sense, that would mean, that temperature had to go down..

[@katzen3314]

Thankyou! I knew something wasn't right there

[@Wemdiculous]

Why is the volume of the detonated fuel so much lower than the volume of the deflagrated fuels? Is it because these areas are the same, but they’re using less fuel?

[@TheImmortuary]

Its didnt look like the area under the curve was that much different, but then I realised the x axis was logrithmic.

[@fedomandez]

I was thinking the same

[@cthulhufhtagn7520]

Y axis but yeah

[@MelindaGreen]

I didn't notice that and was puzzled too, thanks. #NotAllAreas

[@suicideistheanswer369]

Thanks, I was confused.

[@nam3go3sh3r3]

what do you want a cookie?

[@johnslugger]

*We researched this in 1982 when working at Aerojet/Rocketdyne and they are very LOUD engines (((())). We also dropped lead pellets into the flow and come up with a hybrid machine-gun that shot 25,000 rounds of .30 Cal. per second at 3100 feet per second. The US Navy still thinks this type of "Detonation Gun" could take down hyper-sonic war heads by creating a near solid wall of high speed flying lead or ceramic pellets.*

[@arielhermoso4262]

@johnslugger : Why no "prototype" gun was built, out of such finding with RDE technology... It must be called "gasoline gun", "benzene gun", "propane gun", etc.!!...😊😊😊

[@yaseen157]

How exciting! I was fortunate enough to work on a detonation research project for my master's thesis at university. It took us something like 7 different tests over a month long test campaign to finally get a detonation, very finnicky stuff!

[@Tron-Jockey]

Did anyone else notice that that design of the special inlet/injector valves (referred to as fluid diodes), shown at 10:54, is a version of Nikola Tesla's "fixed-geometry passive check valve designed to allow a fluid to flow preferentially in one direction, without moving parts", patented in 1920, U.S. Patent 1,329,559. I believe this was confirmed by UPI Science News article, May 17, 2021

[@Benoit-Pierre]

yup. many other comments talk about it.

[@TheDJOblivion]

Tesla was such a technological genius. His understanding of electrical/magnetic mechanics and fluid dynamics is unmatched. We desperately need a new newton/tesla/Einstein guy.

[@user-tm9qs7jo9j]

Every single person went straight to Tesla valves immediately

[@zylaaeria2627]

Really have to appreciate the precision modern engineering allows. Crazy to think this stuff was only conceiveable even just a decade ago. This stuff won't just affect rocketry. Give it time & it will improve just about every other vehicle you could think of.

[@detechno436]

It's great that pressure-volume diagrams are used to compare efficiencies. However I think that the horizontal line from 1->2 in the diagram of the gas turbine is not about the compressor? The compression process is an adiabatic process that increases the pressure and temperature, which should be 2->3. The flat line is where the open-loop gas turbine engine gets cool, fresh gas from the atmosphere, so the pressure is the same, but the volume is much lower because the gas coming in is cooler than the engine's exhaust.

[@AeroconX]

I agree

[@ShireIO]

11:01 This is a Tesla valve, it's been around for over a century. Fascinating it's seeing use again in such cutting edge technology.

[@kaitlyn__L]

Thank you very much for explaining how this integrates the aerospike nozzle. I saw it in the test units, and wondered if this was actually the next phase in the aerospike research they were doing a couple decades ago, or whether this was something totally different. I can now see it’s kind of both - you could do an aerospike engine without rotating detonation, but as you point out they are natural partners.

[@CHMichael]

Tesla valve - it's amazing what 3d printing has done so far and the possibilities we can't even imagine today.

[@stints]

That man truly revolutionized everything.

[@catalintimofti1117]

​@@stints he really advanced mankind And as a reward he was hated and shunned We didnt deserve this man

[@AllisterCaine]

Yup... It's absolutely mind blowing times we live in. Can't be long until cancer will be a thing of the past and and we have will be bothered by the problems coming from humans living forever...

[@damonedrington3453]

Once we learn to 3D print some more varied materials I expect the technology to explode a la computers in the 90s and early-mid 2000s

[@mattshu]

why wasn't he mentioned once during that part?

[@AniMageNeBy]

Interesting! Heard about this some years ago, but back then it was considered not viable because of instability. Guess they're slowly getting better.

[@slinkeyj3]

That's the game of science, research, and engineering lol. Always trying to push the boundaries of what's possible. You find a breakthrough that allows a new concept to work, but then you need to research and develop it to allow for said concept to be able to function more efficiently and/or longer. Rinse and repeat when you think you've hit the limit of current technology lol

[@Merennulli]

This is a lot further than I thought this design would get. I am stunned.

[@Hyo9000]

They have progressed so much, omg! I’m hyped to possibly see a RDE being used for space missions during my lifetime. Thanks for the video ❤

[@ethanbaer65]

Just as an update, they conducted a different test in december of 2023, and were able to maintain a thrust of 5800 lbs for 4 straight minutes.

[@scottrlindell596]

Great job by the graphics team - really helped in explaining things. What I love is the thinking: "So, we don't have any material that can support use making a rocket whose exhaust is supersonic all the time?" "Right, but we do have material that can support supersonic exhaust SOME of the time." "I know! Let's rotate it!"

[@brynclarke1746]

To be pedantic, all rocket *exhaust* is supersonic, it's having a supersonic flame front in the combustion chamber (and thus having combustion at a higher pressure than the fuel/oxidiser is delivered at) which is new

[@youtubecommenter-on9kd]

Interesting choice. Putting out a video on such a REVOLUTIONARY technology on April 1st...

[@Grimm211]

The Rocket/Turbine Cycle - Brayton Cycle described at 8:01 got it wrong. 2-3-4-1 is the order he described in the video. 2->3 compression 3->4 burning fuel 4->1 expansion 1->2 exhaust kzbin.info/www/bejne/rX2od4qfZsmKo7s Got a good explanation

[@badapple2221]

Thank you very much

[@wagnerrp]

You're not suggesting that the purpose of a compressor is to increase pressure, are you?

[@derMor97]

@@wagnerrp That is the purpose of a compressor

[@garrusarchangel4562]

When I watch videos like this, it makes me believe in humanity and our future. We have many huge problems: climate change, pollution, wars, energy deficit, extinctions of species, and so on. But we can overcome everything! Thanks for the inspiration:)

[@jpteknoman]

for most people, 5% doesn't sound as much of a difference because the average person thinks on a small number scale. a 5% discount on something that costs 50 bucks (an small everyday number) is 2.5 which is pretty much nothing, but a 5% discount on something worth a million is $50k which is significant.

[@robob4465]

The thing is,with all the fancy and shiny manufacturing tech involved,it'll likely actually be more expensive than a disposable bell nozzle when you compare total launch costs. Hopefully the engine itself is light enough to at least build extended range rockets

[@theomaia1460]

this looks like a really interesting video, I hope its not april fools

[@billlhooo6485]

Good to know that 3d metal printing is coming more viable and more cheaper.

[@integza]

Gotta love the almighty RDE

[@davidaugustofc2574]

The tomato king is here

[@fiercemonkey1]

Homie, you so need to build one! But, please do it safely, and keep trying if you don’t succeed. 😊 also, love ur vids, and maybe run it at a much slower rotational velocity and maybe use some “em” fields to stabilize the flowing plasma? Think about it, you can fry a lot of tomatoes 🍅 with that kind of boom 💥

[@morkovija]

found out about them in 2016 and been waiting ever since to see them advance. can't imagine how bad it is for the guys who envisioned them decades ago and never got to see them being produced

[@Benoit-Pierre]

some research take over 50 y ... hope you were very young in 2016.

[@mauricep6924]

I’ve always been obsessed with Aerospike Rocket Engines and was disappointed that they never made it past testing phases. There is hope still yet!

[@Cheebzsta]

So I'm a big Tesla turbine enthusiast and, having come to accept its limitations, got into trying to understand the hypothetical areas where it would at least be uniquely advantaged. One of those was its ability to eat pressure waves without issue and the fact that assembled alternative patents outright paired his fluid diode (the "Tesla valve" or valvular conduit) with the combustion chamber. Been playing with that idea in my head of a rotating detonation rocket engine utilizing the valvular conduit for years (something Integza's talked about) and to see 11:00 made me throw my arms up in celebration. Us Tesla valve detonation lovers were right!

[@prasiddharajgurung]

That man was too ahead of his time

[@varunahlawat9013]

Fingerprints on the laptop screen in the animation made me realise that you've gone so far in 3d renderings. I appreciate it man!

[@edwardsunnyboy]

What a coincidence that you published this video as I'm studying compressible supersonic flow for my aerospace class 💀

[@ok0_0]

[@vx8952]

These videos inspire me as an aerospace engineer to imagine how the future of engineering is going to be like and this one was just as great as all the rest, Thank You! I really hope the development of these engines continues, they look so futuristic and will hopefully make space travel more efficient 😄🔥🔥

[@MoonshineSazerac]

Imagine only just now getting into rocket science, and dreaming of being one of those engineers, and the sheer f*cking VOLUME of stuff you'd need to learn compared to, say, the 60s, or the 30s, or hell even the late 1800s, is utterly baffling. I have mad respect for the folks that deal with this stuff because their mind and their brains and their analytical imaginations are just SO far beyond the base-level pedestrian.

[@Youbetternowatchthis]

Absolutely wild! That injection inlet design and manufacturing alone has surpassed engineering and became magic. This is beyond insane. The wild stuff humanity can do nowadays keeps blowing my mind... Oh and NASA still got it!

[@leadboots72]

It's a tesla valve.

[@Youbetternowatchthis]

@@leadboots72 holy **** it's true. This man really was ahead of his time!

[@leadboots72]

@@Youbetternowatchthis Yes he was.

[@virutech32]

Absolutely gorgeous visuals, just WOW

[@Appletank8]

Everyday Astronaut did a good video on the setbacks of Aerospike engines, chief among them is the massive amounts of heat the spike needs to endure with few ways of cooling, which often results in self destruction.

[@Br3ttM]

Some of the advancements that allowed this engine were an alloy good at resisting and conducting heat, while being 3d printed to put in cooling channels that couldn't be machined.

[@slinkeyj3]

Yuuup. And that probably has a LARGE team of researchers and engineers by itself just trying to improve upon it's longevity lol. It's crazy how many people will be dedicated to improving and developing just one singular component

[@princesscadance197]

"But engineers and scientists are stubborn kinds of people. When they hear 'uncontrollable', all they hear is 'not yet controlled.'" I know plenty of people in my life who are stubborn like that. I wonder if they're engineers.

[@xandon24]

One of the major things to understand is that controlling a chaotic system is the EASY part. We can use machine learning to do that consistently, the hard part is MODELING the system accurately enough for a machine learning algorithm to come to a correct solution.

[@radpixelbomb659]

I learn more from your videos than I do from science class

[@brentwilbur]

Except when he spews climate change nonsense.

[@scottnj2503]

This is IMHO, the unintended but not surprising result of "No Child Left Behind" and underfunding of the public education system on whole. If you are a HS or College student. Good on ya for seeking more knowledge.

[@gilbertlopez]

climate change is real, humanity is worsening the effects

[@andrzejostrowski5579]

No, you don’t.

[@mrcat5508]

@@andrzejostrowski5579what

[@darkxxprincexx]

A new aerospace video! Thank you Real Engineering!

[@Lucas-ys7qq]

First explanation of RDE that I actually understand. Awesome!

[@twistedyogert]

If Dr. Wernher von Braun was still alive he'd be mesmerized. Detonation was his nemesis when he helped design the N1, and now NASA could possibly use it as the literal beating heart of future rockets.

[@Marisa_arts]

I'm not sure if I said this bey, but I was making and thinking about this type of engine for my sci-fi settings and I'm glad that I wasn't the only one who have since it is really cool and just a system we need! Other than that it is an Aerospike Bell Cone Thruster combo with the spike being just exposed enough for the flames to reach. Though there are some issues I see when it comes to Space use and that is the fact that we don't have an atmosphere to keep the pressure intact. One solution I thought about was to make the cone retractable to get a traditional bell thruster but still keep the normal pulse feature so it can still be on trajectory. Other than that, fusion or ion systems can help with that once there.

[@skgough4386]

The 3D rendering in your recent videos has been on another level! Is Mustard doing the modeling?

[@michaelogden5958]

Very creative! I hope they get it all worked out! Thanks for the video!

[@rickhobson3211]

You mentioned comparing a d-engine to a gas turbine engine. I wonder if an air-breathing detonation engine. A 5% increase of efficiency would greatly benefit air travel too!

[@litkeys3497]

DARPA is trying to build an air-breathing RDE to put on missiles & aircraft. My understanding is you could potentially get 25% longer range on the same fuel, which would be HUGE. Only caveat is that the use case is probably limited to supersonic aircraft which means we probably won't see them replacing high bypass turbofans on airliners soon

[@EveryoneWhoUsesThisTV]

Pulse and rotating detonation engines are crazy loud, but can be used in high-altitude air travel... :) Effic increase should be more around 25% Pulse detonation engines are already around 25% more efficient, so rotating should be too, or they won't bother with them... NASA have a pulse detonation engine powered aircraft...

[@yesyes-om1po]

airlines have tight margins, I think this could only be used for extremely expensive private jets meant for the likes of Bezos. A 5% increase isn't much at a Jet's level. It is a modest figure in that regard, not game changing but still welcome.

[@Br3ttM]

The reason fuel efficiency matters so much for rockets, is that fuel requirements are exponential. For a given thrust, without air resistance, your change in velocity is inversely proportional to mass, so adding more fuel weight means you accelerate more slowly, taking more time and fuel for the same change in velocity, so you need more fuel to move more fuel. Efficiency makes the exponential curve shallower. And under-expanded exhaust doesn't just lose efficiency, the much more important factor is that it is unstable, and can throw off balance or even damage the nozzle. The space shuttle, which had to use its main engines from sea level to space, used a trick by changing the curve of the nozzle in a way that kept it from separating and becoming unstable even when it was under-expanded.

[@whynotanyting]

It awesome seeing new improvements in tech being developed. It's easy to think that everything's been discovered and explored, yet our best photos of Pluto came from New Horizons in 2015. I always assumed we had high quality photos from years prior, but no, we're still learning.

[@HuntingTarg]

6:00 I remember Scott Manley covering this in a video on the development of the F-1 engine. I love how NASA made a literal bomb-proof engine. 8:50 Interesting that the increases in thermodynamic efficiency for Hydrogen and Methane are almost the same. Also, the fact that the exhaust travels at multi-Mach speeds should make for an excellent booster engine. Perhaps SpaceX will purchase something from NASA for once.

[@mobiuscoreindustries]

That is correct but there is also likely going to be severe scaling issues just like flow instability isn't an issue for small chambers but became lethal for the F-1. The larger the chamber, the more the fluctuations will increase, both with higher highs and lower lows. This may make scaling the engine more difficult. Also, I can see how flow rate for such an engine could be limited. Due to needing to constrain the combustion more, you will obviously end up with less mass flowing through your system. Which isn't a problem for orbital stages, because there only efficiency matters. But during ascent to orbit, thrust matters just as much, and usually far more. Not only do you actually need a set amount of thrust to just get off the ground, but you gain far more payload to orbit by spending less time losing energy to gravity, even if the engine ends up being less efficient. We saw this with raptor engine development, and how via changes to their thrust and the vehicle's flight enveloppe, increasing thrust and spending less time fighting gravity, they basically doubled the initial payload despite some losses on the ISP of the vacuum engine. A far better trade than a 5% efficiency increase. I see this absolutely sweeping high energy upper stages tho. Stuff that still need to fight gravity for a bit but also needs to fling things far away.

[@pscheidt]

Finally! A real use for the Tesla Valve.

[@sakiskarakasidis]

👍

[@weasle2904]

It's not just the inherent fuel savings of the engine that's absurdly impressive, it's that Nasa proved this is a viable propulsion method to use with Aerospike engines, allowing the engine to maintain high efficiency at all altitude levels. This is unlike traditional bell nozzles which are designed with a particular exhaust pressure front at a given set of altitudes, necessitating different nozzle designs for different stages (making them difficult to use for SSTOs)

[@origamiscienceguy6658]

Aerospikes still have the main problem of heat dissipation, which limits their size.

[@weasle2904]

@@origamiscienceguy6658 I think more advanced material science and the advent of infinitely complex 3d printing will alleviate this issue.

[@origamiscienceguy6658]

@@weasle2904 It can alleviate the issues, but there is still going to be a fundamental upper limit to the size of aerospike nozzels, since as an engine gets bigger, the surface area available for cooling grows slower than the energy of the engine.

[@IncroyablesExperiences]

Very very interesting! Thanks for your work About the PV chart I'm not sure the the compressor "decreases the volume at constant pressure" (it's the heat exchanger in a power plant or new fresh air intake in an aircraft turbine), the compressor is more likely the step 2 to 3 is your diagram. The intake is point 2 :)

[@franzperdido]

yeah, this part also made me think. I think you're right and it's not correctly explained in the video.

[@draglorde]

I love the animations and the sound effects. a lot of research was very well presented! thank you for this great video

[@Harry-wx3nf]

Good videos man. I love how you explain everything, I learn a lot.

[@Angl0sax0nknight]

Love the engineering of these videos, it’s amazing what can be designed and the innovation to overcome problems.

[@TippyHippy]

I put my hamster in a sock and slammed it against the furniture.

[@sharkbitesback2749]

@@TippyHippyjust because of you im liking this comment

[@adawg3032]

This is so cool. At supersonic airflows, beurnellis principle reverses in the sense that a divergent duct exhaust will increase the velocity of the charge. F=M(A) says that the faster the fire shoots out of the flame end, the more the pointy end goes up

[@allisterlobo7107]

damn that unidirectional valve is amazing. Thanks Nikola

[@recurshawn]

The last time I was this early, we were still sending manned missions to the Moon

[@gamefrySE]

For anyone that wants to know how an aerospike engine works, Everyday Astronaut has a great video about them that you can watch right now. He's got a ton of other rocket engine explainers that would not feel out of place on this channel and they're all well with checking out.

[@ardag1439]

I love seeing rockets rotate and detonate but this isn't too bad either.

[@vast634]

As long as the fuse is long enough to get away

[@Gordofilms7]

the fluid diode injectors are such a simple, elegant solution to the backflow problem

[@henrypotter3024]

When he started talking about 3d-printing the engine my mind started to wander to something like a nanobot that could actually remove material to build it. Then I realized that if we actually had nanobots, they could actually build the materials as close to perfect as we can get.

[@OriginalAustinOblivion]

They’d be perfect precision machines, though, I feel they’d be used in the medical field far more than they’d be used in any other sector for the exact same reasons. Oh, also 3D printing might even give way to nanobot technology

[@Martin-zd8eb]

Oh laser 3D Metal printers can construct in nm scale....but for this application it's not needed

[@anmolgupta-bj5ce]

Real way to learn engineering. Thankyou 🙏🙏🙏🙏

[@damianw.415]

Nah. Mathematics are the real way.

[@anmolgupta-bj5ce]

Mathematics is a tool used to answer questions for physics 🙏

[@Ravenor907]

You just had to release this on April 1st didn't you lol The first 5 minutes I thought this is going to end up being a joke of some kind

[@mycosys]

the ol' double bamboozle ;)

[@gingerbread2771]

I thought rotating detonation engine prototypes were a thing for a while., is there anything special about this one that I'm unaware of? In any case, great video!

[@badapple2221]

It actually worked for quite a long time, before this one theyd either not work or explode.

[@adamh1228]

they have been, but im pretty sure only recently have they been able to run the RDES for minutes at a time, rather than seconds.

[@t_c5266]

Yes, it actually runs

[@leadboots72]

Yes. Now it comes with electrolytes.

[@cjwrench07]

Those prototypes all have inherent design flaws due to the materials used. NASA’s new design, allowed by the invention of the new copper alloy, is the major revolution.

[@GuardsmanBass]

"103 ton decrease in fuel" - WOW. That's enormous, and would have nearly doubled the Saturn V's payload capacity. Imagine that with a Falcon 9, going from 17 tons to LEO with first stage reuse to nearly 40 tons with first stage re-use.

[@johnlivingston37]

- His definition of detonation needs work. - Yes a detonation will create a pressure rise, but so would a pump. It is not a question of Isp, either type rocket can be made to have the same. For the same Isp, the conventional rocket will need higher pressure pumps than the detonation rocket. The question, then, is which rocket type is better to engineer, an unsteady rocket with higher peak pressures with lower pressure pumps or a regular rocket with higher pressure pumps? My bet is on the conventional rocket. There may be some niches where a detonation engine might win, but I don't see them yet. John

[@andrewreynolds912]

I saw this on new atlas, and it was nuts when I saw the vid of its testing

[@Honjudd]

By far the most elaborate April Fools day video I've seen!

[@estro8817]

A graduate student in my university actually built a small version of this engine for a professor for research. So cool to see a breakdown about it!

[@pxm3097]

One of the most informative videos on dentonation engines. I am actually working on designing the valves for the same. The concept of detecting pressure feedback through viscous and inertial fluid resistance is the key. I was fascinated to learn that it was designed by Nicola Tesla and named after him, the Tesla Valve.

[@abcde_fz]

Being a 'well informed' follower of scientific progress, (rather than an actual practitioner of research and experimentation), I have to say that this engine type is one of the most fascinating examples of fluid dynamics of the many different 'factoids' of that area of research that I have ever heard of. Super cool stuff... 🙂 🙂 🙂 🙂

[@TurnRacing]

But how does it compare to a Raptor V2 engine? The F1 isn't exactly a modern benchmark...

[@joshtulley4807]

this

[@beez1598]

Hard to compare, the f1 was built with a different application in mind than the v2 and has really been the gold standard for comparisons since it flew. Fewer failure points and more thrust per engine vs lighter smaller engines that can be grouped in clusters. It’s hard to compare early scale testing of the rotating detonation engine to anything that has or does currently exist. Its a big deal regardless, but I think we are a ways off from seeing how it compares to either engine.

[@ilikeyourname4807]

The unique thing about the Raptor is its fuel/oxidizer precompression layout (engine cycle). Otherwise it's still a deflagration engine. The engine cycle of this rotating detonation engine prototype wasn't mentioned and I think it's probably something very traditional because it's not the point of the experiments. Comparisons between the two are kind of pointless because they gain their additional efficiency from different sources that could in theory be combined. Imagine a full-flow staged combustion rotating detonation engine. The holy grail of chemical rocket design

[@VG_164]

I wonder this as well. The F1 is a pretty damn inefficiant engine in every metric put pure thrust, and even there the RD-170 beats it while being a much more efficiant engine. They should make the comparisons to what modern engines like the Raptor 2 are capable off rather than F1, even if the later is iconic.

[@ilikeyourname4807]

@@VG_164 He compared the theoretical best performances, not actual engines. The F1 was an example he used to explain how deflagration engines work and go off on his tangent about combustion instability being small detonations

[@JekleFPV]

The insurmountable issue with aerospikes is dissipating heat. Does that alloy basically solve that issue and/or how is this engine type affected differently regarding heat dissipation?

[@petersilva037]

rotating detonation helps with that to some degree, because he heat is rotating around the spike rather than surrounding it on all sides at once.

[@JekleFPV]

@@soulextracter that doesn’t really scale well if I remember correctly from the top of my head. Everyday astronaut has a good video on the whole thing if you really wanna know

[@JekleFPV]

@@petersilva037 that figures, but it’s unclear to me if that makes the aerospike actually viable for larger scale engines

[@Zigglegarf]

It's literally the first question that comes to mind when I hear about an aerospike engine, and the biggest problem with them, especially cone-style engines. I'm surprised he didn't even mention it, especially after all the bits of footage that clearly show burning copper.

[@Br3ttM]

The video did mention that this alloy was good at conducting heat, which, along with being 3D printed to allow more complex shapes, would make cooling it easier. The video focused on complex injectors, but complex cooling channels are also valuable.

[@THE-X-Force]

This was incredibly well presented and explained. I learned a lot. Thanks for the great video!

[@vitormoreno1244]

For detailed aerospike engines I recommend the Everyday astronaut channel, Tim has made a lot of detailed videos about rocket engines

[@godspeed133]

his videos are just about the best I have found for explaining rocketry for the layman, they really are outstanding. Even heard rumours that they've been used on aerospace engineering courses although not sure how true that is.

[@vornamenachname2625]

1:00 With a 5% higher efficency / a 5% higher specific impulse you safe more than just 5% propellant. This is because the rocket has to accelerate the propellant.

[@minemasterSAM]

This boutta be good

[@Kirhean]

It occurs to me that the design of this engine might have applications for nuclear fusion reactors. The rotating detonation strategy could help to manage pressures and temperatures in the reactor, taking some of the load off of the magnetic containment.

[@WesternUranus]

Detonation engines look like someone wanted to do an internal combustion engine in space. The cyclic nature, the flywheel in the form of a shockwave, the mix being pushed into the chamber, the precise ignition timing, I see so much in common. Hopefully it will have the same impact on space mobility as its analogue did on Earth (minus the greenhouse effect id course 😅) I sure hope these won't come with a gearbox lmao PS : This channel is really awesome, in the strictest sense of the word. Thanks

[@SupermanBlack1987]

This looks like an early stage impulse drive that you would see in sci-fi. If we can transform this process into an ion drive you basically got any impulse drive you ever seen any sci-fi movie that's crazy.

[@aakarshtripathi]

As a Metal Additive Manufacturing Engineer, I can’t explain in words how significant these kind of tests are. NASA is at the forefront of developing cool tech using Metal Additive Manufacturing Technology, and I wish I get to work with them someday in the future, but alas, US ITAR requirements bar me from it. Hope someday this changes and I get to meet and work with these geniuses!

[@That_Montage_Nerd]

Been a subscriber for years. And this is kinda wild, because for my college assignment due in a couple weeks, I decided to do a literature review of conceptual and experimental rocket engines that may be used in near future. And here's the wonderfully timed upload from a familiar channel introducing me to one!

[@CortanaCH]

I fucking love this channel!

[@sudhanshuprasad2666]

I hope this isn't an april fool

[@thierryvt]

10:50 isn't that an adaption of the Tesla valve? Also 12:40 that explains why the falcon rockets exhaust plumes seem to expand so much as they get higher. Fascinating video as always, thanks!

[@lorisgraf8804]

small mistake at 8:06 "A compressor decreases its volume at constant pressure" I think you meant an ideal compressor decreases its volume at constant entropy", otherwise the compressor would be cooling the gas, if what you are saying was correct

[@Chuck_vs._The_Comment_Section]

Epstein Drive, here we come!

[@ThePixelated_kris]

What?

[@SimJoSt]

​@@ThePixelated_krisThe Expanse

[@seth_sesu]

The efficiency gain is ~25%, not 5% as mentioned in the video. As reported by a number of publications.

[@luigeribeiro]

5% is a increase in the specific impulse, or exhaust velocity.

[@seth_sesu]

@@luigeribeiro in any case, the narrator said there is an efficiency gain of 5%… that’s not correct

[@luigeribeiro]

@@seth_sesu In a rocket engine fuel efficiency is Isp. The 25% value is an increase in thermal efficiency.

[@jameslmorehead]

"Fluid diodes".....can we give credit to the inventor of these? Nicola Tesla was a man of many talents and generations ahead of his times.

[@robertappleby6683]

How could the revenue from ads have possibly dropped? youtube has been getting more aggressive with them pushing me away from the platform with irritation until I get sucked back in by something genuinely interesting. Great vid btw 👍 you damn harpy.

[@solastro5595]

The return of the aerospike engines, I'm so happy.

[@MrGrombie]

Anyone ever remember the saying back in the day people would say "I don't understand because I am not a rocket scientist" Meanwhile, we are watching this for fun.... 😂