A Rocket With & Without a Turbopump - Spica Performance Comparison

[@CopenhagenSuborbitals]

'tis a long video, so here are the timestamps: 01:25 Intro by Orbital Machines CEO 04:43 Orbital Machines Recap of 2019 07:27 Reveal of Functional Pump Prototype 09:39 Jacob Larsen Intro on Copenhagen Suborbitals 11:55 The "Why?" of Copenhagen Suborbitals 13:42 Who is in Copenhagen Suborbitals? 14:52 Copenhagen Suborbitals Timeline 16:26 Is Space Too Difficult? 17:27 Nexø II Launch 18:46 Being Under The Rolling Thunder of Nexø II's Engine at Sea 19:45 Reaching Space is No Longer a Dream 20:29 Turbopumps - The "Holy Grail" of Rocketry 22:29 RD-170 Turbopump vs a Wind Farm 24:12 Turbopumps in the New Space Industry 25:11 Turbo Pumps - The Classical Approach (Gas) 25:49 Turbo Pumps - The Modern Approach (Electric) 26:49 Spica Performance Increase Using a Turbopump 27:58 Advantages of Electric Turbopumps 29:15 Copenhagen Suborbitals Developments and Swirl Injector 30:17 Spica's Propellant Consumption Demonstration 31:50 Outro

[@BillySugger1965]

Excellent, I’ve been thinking for some time that an electric turbo pump would make a substantial difference to Spica, but didn’t imagine a 25% mass saving! What was missing from this was the CS rationale for continuing with a pressure fed system. Is that because of technology readiness issues alone, or something else?

[@CopenhagenSuborbitals]

You are exactly right. We needed to start building the rocket already and the TRL for the electric pump was not quite there yet for us to completely move away from a pressure regulation system.

[@RWBHere]

@@CopenhagenSuborbitals One question arises, and it did not seem to be broached during the presentation: I gather that the electric pump needs to run for around 210 seconds. How much will the battery weigh?

[@CopenhagenSuborbitals]

@@RWBHere If you're talking 210s for Spica, then you are over by a factor of more than 3. :) Not too sure about the weight of the battery pack yet, sorry.

[@baacco.3658]

I’m a sophomore in aerospace engineering currently, and it’s projects like yours that get me excited! Keep it up all! -Isaac

[@CopenhagenSuborbitals]

Thank you Isaac! It's a pleasure to hear that. Great time to be an aerospace engineering student, we wish you good luck!

[@tuomomutru8002]

Sorry to bother you @baac co., I have a question for you. I've been thinking to do my masters in aerospace engineering, but I am not sure to take it. Because it means me to move to other country to study that subject. Do you recommend me to take it. Next year I will graduate as an bachelor of energy systems, so I was thinking that this would help me in masters of aerospace engineering😁🤙

[@TheArcker]

Hey guys ! Can't help to notice that you and the guys from Orbital Machines used several times the term "Electric Turbopump". The definition of a turbopump is "a pump that is driven by a turbine". But this is not the case here. What you are referring to is commonly known as simply an "Electric Pump" or also a "Motopump" (less common). The first being the term used by Rocket Lab, with their "electric-pump-fed cycle".

[@CopenhagenSuborbitals]

Yes, you are right. We'll need some time to readjust our vocabulary. 😁

[@jonolavbjrndal9574]

@@CopenhagenSuborbitals Please... Say "electric pump". My inner nerd cringes every time I hear you say "turbo-pump".

[@kerai9961]

How many spica missions are you guys going to have before the manned launch?

[@petermaersk-moller3014]

Uncertain at the moment. Nasa seems to require 7 or 9 flown Falcon 9 missions in a row without incidents to man-rate the rocket, while allegedly, the SLS only will require one. The future is hard to tell, but it is my impression we would need several launches before considering a manned endevour. So reusability to some degree will become important to keep cost down - or at least that is how I view it for now. But one should never be afraid to reconsider as experience is collected.

[@SciFiFactory]

Nice! Also: You guys have already surpassed your goal of being a GIANT inspiration by a million miles! :D (Inspiration is measured in miles , right? *scratches head)

[@CopenhagenSuborbitals]

We use metric. ;) But thank you, it's a pleasure to give that back!

I'm not paying for the goal, I'm paying for the journey. 👍

[@CopenhagenSuborbitals]

@ We really appreciate that!

[@RWBHere]

Nice presentation, and a good promotion of electric pumps for use with rocket motors. That was a youthful picture of Peter Beck! And it was somewhat mesmerising to see the 'donations' counter advancing during the presentation. Thank-you! 🚀

[@OrionAerospace]

Electric turbomachinery is so efficient its mind-blowing. It would be great to see the bpm-100 with electric pumps! Wonder if Orbital Machines will offer a battery "hot-swap" solution like rocket lab use :D

[@CopenhagenSuborbitals]

We'll just have the astronaut throw the empty battery pack out the window.

[@OrionAerospace]

Copenhagen Suborbitals sometimes the simplest approach is best 😂

[@maxk4324]

While electric pumps ("turbo" implies there is a turbine) are unique and appealing for small vehicles in many ways, efficiency, at least on the basis of mass savings, are actually less efficient than turbopumps. This is because of the energy density of chemical propellants as well as how the usage chemical vs electric energy stores affects mass over time. On the energy density side, storing energy to be used for pumping in chemical energy can be done with far few kg of propellant per joule of energy than batteries. This is why the most efficient electric cars on a full charge still can't beat the range of the most efficient gasoline cars on a full tank (and a full tank is still probably lighter than the weight of the batteries on the electric car. Don't get me wrong, I'm all for the EV revolution, but it's important to be realistic when characterizing the strengths and weaknesses of any technology. On the the mass change side, turbopumps have the advantage of decreasing the total vehicle mass as they operate (ignoring the mass loss due to the pump's sending propellant to the engine, which would happen in either electric or turbine driven pumps). This is because once the propellant is used to turn the turbine it then exits the vehicle either through an exhaust duct or through the main combustion chamber. However the mass of a battery does not decrease as you use the stored energy, and so the mass of the system remains the same rather decreasing over time. This is why the Electron second stage does the hot swap. However the theoretically most efficient option is not always the best option. For example, the most efficient chemical rocket engine ever fired was a tri-propellant engine designed and built by Rocketdyne. During testing the highest specific impulse it achieved was 542s! However despite blowing every chemical rocket engine before it and everyone since out of the water on efficiency, it has never and likely will never be flown. Why? Because the three propellants it used were gaseous hydrogen (stored in liquid in the tank), liquid fluorine, and liquid lithium metal. When Liquid hydrogen is only the third most dangerous substance in your propellant system it's time to reconsider your life choices. All in all I would agree with your sentiment that in the case of vehicles of this scale and with companies or teams who do not have the time or resources to perfect a turbopump, electric pump's are uniquely suited to fill the gap. In addition they offer easily controllable and nearly instantly responsive throttling as well as reduce manufacturing cost of the engine by reducing the number of components under high thermal loads. But if we are just talking about efficiency, turbopumps always beat electric unless some miracle in electrical energy storage comes along.

[@Starman5771]

Thanks for ur informational video

[@CopenhagenSuborbitals]

Thank you for watching!

[@StanleyCreative]

Really cool presentation guys! Would be awesome to see an ETP on Spica 😲

[@dand4485]

Love the background music... Makes me think you are just an Everyday Astronaut kind of guy ;)

[@DeanZylman]

very interesting, I would love to work with you guys ,

[@CopenhagenSuborbitals]

Thank you! Not sure if you are talking about Orbital Machines or us, but we are an all-volunteer project. So you are welcome to join any time if you live in or around Copenhagen, just we can't offer you much in return apart from good engineering fun. :)

[@SpeedrunnerG55]

This video had a real sting every day astronaut vibe at the beginning then it died

[@CopenhagenSuborbitals]

Likely because we use his music. ;) But this is not our typical style of video, so check out some of our other ones, if you want to see how we build a crowdfunded space rocket from scratch. Not saying that our content is similar to Tim's, but if you're into rockets, you should find it fairly interesting. You're also welcome to give suggestions on how we could make it more interesting as well. For example what you would like to see and learn.

[@thelittlerubberduck3260]

Hi, I heard I could volunteer building your rocket, but I dont know how to weld. So my thought was, can I learn it from you? Btw I live in denmark

[@thelittlerubberduck3260]

And how will you recover the lifting stage?

[@CopenhagenSuborbitals]

Perhaps you have any other skills? Otherwise you could help out with some less mission-critical welding. There are lots of infrastructure that doesn't need to be welded to flight specification that you could help with. Do you live in or close to Copenhagen?

[@thelittlerubberduck3260]

@@CopenhagenSuborbitals I live in Greve so not that far but what skills could be good to have, cause I really wanna help?

[@CopenhagenSuborbitals]

@@thelittlerubberduck3260 It could be almost anything as long as you are willing to help and are fine doing it for free, as none of us get paid. And we also need people who can see themselves in the project two or three years down the line. We don't have any requirements on how much time you need to work, but we want people to be honest with us and themselves on how much time they expect and can dedicate each week. If you are fine with that, you can send me an email to [e-mail] and we could arrange an interview with you.

[@thelittlerubberduck3260]

Copenhagen Suborbitals Well in 14 years old so does that make it worse or help, and im tall

[@MrStrangeham]

This is good.

[@epasko5713]

Anyone notice the uncanny resemblance to the grinder on your workbench out in your garage? still has me pondering maybe how this idea may have been "Sparked!" Great Work Guys! Please Keep it Up, Your are on the right track, I feel your high energy, Makes me proud just to be a Fan, Thanks!

[@olivergledhill8668]

If your mass budget for the DPR system is 100kg (not including the tank thickness). What type of mass would a 150kw motor + inverter & battery which lasts 50 seconds be ?

[@jnygaarddk]

It does not answer you question, but the slide at 27:10. It gives a pretty good idea of the weight savings.... Much of it from the tank of course. Thinner walls, but also a lot smaller in volume

[@Meddlmoe]

@@jnygaarddk those weight savings were for tubopump system, not for a electric pump

[@Meddlmoe]

Batteries with high specific power are capable of delivering 3000 watt per kg. Withh structure, cooling, inverter etc. You get about half that. So i would guess around 100kg. Specific energy is probably not the chokepoint, unless you use capacitors

[@Haos666]

That is a major uplift! I was wondering how are you planning to deliver enough performance with pressure-fed system. This could be an instant no-brainer upgrade.

[@petermaersk-moller3014]

The current Spica tanks under construction for the first Spica rocket are for a pressure fed system with DPR through heating of LN. However the first BPM-100 engine under development can be used for testing both the the pressure fed solution and a electric pumped solution. When we have electric pump solution, we can build much ligther tanks and drop the LN heater and DPR although a electrica pumped version would still need some gas to fill the tanks as they are pumped empty. So to answer your question, the enngine and tanks are designed to deliver sufficient performance with a pressure fed solution.

[@danimorcos7226]

are motopumps still considered for the BPM25? If so, it would be awesome to get some insight on the progression of the partnership between CS and OM! Cheers!

[@mathiaslist6705]

27:00 and he starts explains why a turbopump is necessary --- without further ado --- and you can't find that no where else on youtube

[@josespeck]

@the little rubberduck @Copenhagen Suborbitals I've seen Buddy Michaelson use rivets in his rocket. Is it possible to make deposits like this and not weld?

[@RiderRickMaker]

YES!

[@thanansan]

Thanks for the experience. Indeed, the electric pump fed engines is more efficient for LEO businesses.

[@Meddlmoe]

I am missing the weight of the battery capable to deliver that amount of power.

[@ufuker5754]

Lithium sulfur batterys look it up

[@povilasbrencius7314]

What. You have Ltihuanians?

[@CopenhagenSuborbitals]

Taip, ne vieną. :)

[@povilasbrencius7314]

Malonu taip žinoti ,kad ir Lietuviai nori dalyvauti kosmoso programose😀

[@jorgenskyt]

It seems we attract the best people from all over the local part of the galaxy: Jutlandians, Lithuanians, Bornholmians, Romanians, Germanians, Sealandians, Netherlandians, Francians, Spanishians and so on ... :-)

[@danfrederiksen7397]

190MW sounds a bit extreme. Are you sure of that value? At that rpm the shaft has to deliver 130000Nm to produce 190MW. 230 rotations per second.

[@jnygaarddk]

A little bit of. Should be 170MW acc to wiki. Wonder if that's why they called it RD-170.... en.wikipedia.org/wiki/RD-170

[@jnygaarddk]

Iøvrigt større fan af SSME/RS-25 selv om den _kun_ laver 71.000 HP til fuel pumpen... Ved 35.000 RPM. Vilde krafter. en.wikipedia.org/wiki/RS-25#Turbopumps

[@HaraldSangvik]

@@jnygaarddk Wiki artikkelen sier både 170 og 192 MW, men encyclopedia astronautica sier 170 MW, så det er nok rett. www.astronautix.com/r/rd-170.html

[@CopenhagenSuborbitals]

Yes, the value is true and it is extreme. :) From Jacob: "One can seriously do amazing things with 502 bar of 772°C gaseous oxygen. As it runs all of the oxygen through that turbine, you have a mass flow of 1.8 tonnes of gaseous oxygen per second. 189.3MW turbine power? Yes, absolutely! This is why I love this engine so much. 😁"

[@danfrederiksen7397]

@@CopenhagenSuborbitals how does that fit with the electric pump being 150kW? engine is more than 1000x less thrust?

[@spieltmit]

EA music was very obvious to hear :)

[@abdulrahmanhussain3943]

How can I obtain your electric turbo for my energy generation project Rocket is zero to me

[@CopenhagenSuborbitals]

You can contact Orbital Machines through their website for inquiries.

[@RocketCardragracing]

For a video on rocket science, play it at minimum of 1.5 speed to make it watchable, the type of person watching this video isn’t a non “coffee” guy ifykyk

[@equation1321]

epic

[@acekiwi7184]

Um ever heard of Rocket Lab in New Zealand? Ten flights to orbit with electric pumps......

[@CopenhagenSuborbitals]

Yes, that's why there is a picture of Peter Beck at 28:02 with their electric pump fed engines. If you skipped through it, the point is that there are no commercial suppliers of electric pumps in the industry. Rocket Lab has only developed their own pumps for their own use, and any other company would need to do it themselves too. That's where Orbital Machines come in, offering a commercial solution for any rocket engine.

[@stephenhumble7627]

How does electric compare performance wise with designs like the soyuz rockets that use a low temperature turbopump that runs by decomposing hydrogen peroxide with a catalyst. ? These hydrogen peroxide turbo pumps do not get very hot and so you don't have to use expensive materials but maybe this can give an advantage of a high energy density hydrogen peroxide driven pump and the vehicle looses weight as the hydrogen peroxide is consumed during operation further saving on weight - and the exhaust water and oxygen could themselves be used as propellants as well. I like that the electric pump is a way to get a pump fed rocket flying and save allot of weight compared to a pressure fed design but it seems like they would not match the performance of a hydrogen peroxide turbopump design which could save even more weight still. ?

[@dajsinjo]

Can you add turbine-generator with combustion chamber tap-off, or gas cycle? I guess it would reduce the amount of batteries, which is the only downside of electric pump feed engine

[@wheresmycar9559]

They could, but it would reduce effiency, increase complexity, and bump up engine weight.

[@dajsinjo]

@@wheresmycar9559 yes if you look only at rocket engine, but if you see batteries as part of it then it would reduce overall weight and and increase efficiency at the end.. fuel and oxidizer wasted with tap-off has more energy density then batteries

[@olivermoldenhauer6967]

Hm. Technically great stuff. I am thinking about how amateur your rocket is still going to be, when you get a key component from a commercial company. - I mean, sure you are not making your own microshops or produce aluminum, but you wouldn't just take an off-the-shelf engine. Not saying that this is wrong, but I'd love to know more about your thought process.

[@CopenhagenSuborbitals]

That is a good question. First, we have already proven the ability to produce and reliably run our liquid engines without turbo or electric pumps. But it is also important to note, that there is no 100% guarantee yet that Spica will be running an electric pump. And all of our current production is still working towards a pressure fed system using a LN burner and heat exchanger, which will first be tested on its own, and later on a BMP100 engine as well. So even if we do eventually end up flying with an electric pump, we still expect to have proven capability of 1) producing Spica sized high pressure propellant tanks in-house, needed for a pressure fed system and 2) running a BPM100 engine on a LN pressure fed system. And if after proving that we can choose to save ourselves many logistical nightmares by having a lighter and smaller rocket, while at the same time helping a cool startup prove their technology readiness which will help them do amazing things in the industry, it is, of course, desirable. Those are just my 2 cents. Kindly, Sarunas K.

[@olivermoldenhauer6967]

@@CopenhagenSuborbitals Thanks for this open answer. It's definitely a very valid choice you can make. I'll keep my donation running and encourage everyone elso also to donate to CopSub.

[@CopenhagenSuborbitals]

@@olivermoldenhauer6967 You're welcome. And thank you too, we appreciate you keeping us going! :)

[@donaldrandall5628]

Electric fuel pumps are already putting satellites into space. RocketLab of New Zealand.

[@CopenhagenSuborbitals]

Sure, just as mentioned in the video. But there are no commercial suppliers of electric pumps for rocket engines and that's what Orbital Machines is trying to bring to market.

[@Holy-Terrorist]

**=** Cool, like similar to ionic propulsion ;)

[@txm100]

That applause is WAY to loud.

[@Ihavetruth22]

Crowd funding. Thats ridiculous. I don't see this working out at all.

[@CopenhagenSuborbitals]

If you are talking about Orbital Machines, then they have already completed two successful crowdfunding rounds to raise enough capital for their MVP and have already started testing the first prototype a few weeks ago in a Hydro Power Lab at NTNU. In case you are referring to us, then we are currently building our 8th crowdfunded rocket. :)

[@kevinrushmere]

apple started out in a garage and hewlett packard on a kichen table and now they have the hp reverb g2 vr headset that i will buy, and finally IKEA started off selling pencils

[@BaronLemon]

Bullshit. Sorry for using this word, but this the one that came to my mind after watching this video. And I'll explain why. When Jacob mentioned the weight reduction as a result of using electric pumps, he "forgot" to mention the added weight due to need for batteries to power those motopumps. And that is huge. And this the reason why gas powered turbopumps are used instead of motopums, it's not like those stupid rocked engineers haven't thought about this already. As somebody who worked in the space business, I know that the only reason for which Electron Labs is using electrical pumps is because they failed to make a turbopump work - which is, of course, the biggest challenge when making a rocket. They sell it to the world as a "smart choice", but in reality they are loosing a lot of payload because of this.

[@CopenhagenSuborbitals]

In our case, the weight reductions come from going from a pressure fed cycle to an electric pump cycle. But if you look at the literature, electric pump designs can outperform turbopumps on smaller engines, up to around 100kN, although it has not been proven in practice at that scale yet. Interestingly enough, Orbital Machines have matched turbopump designs of several commercial launch vehicles based on weight (all considered) for even considerably more powerful engines than 100kN class. So electric is here (for some applications) and it has other advantages other than weight reduction, including simpler control, ignition, propellant tank depletion, reusability, and more.

[@BaronLemon]

Thank you for your answer! Of course, for small, pressure-fed rockets, electric pumps can be a source of gain, but for for satellite launchers, like Electron, it's a waste of payload mass. We know how difficult is to make a turbopump, and I'm sure that sooner or later (probably, later), with the advances in electric energy storage technology, electrical pumps will take over turbopumps, but for now, for "serious" rockets, turbopumps have no rival.

[@n111254789]

No one thinks rocket engineers are stupid but just because it was done one way in the past doesn't mean future technologies don't open new doors. They didn't have access to the batteries nor electrical motors that we do now even a decade ago. Mechanical turbopumps have a lot more parts which increases mass not significantly but it needs to be taken into account, as does the fuel required to operate these pumps as it sucks fuel because it is a part of the combustion process that isn't directly converting its energy to thrust its just powering a pump. I understand the energy density difference between batteries and chemical combustion is much more in favor of combustion at the moment and thus they are for now still lighter. The thing is cost per lb to orbit is what a lot of customers care about not everyone is sending something heavy out to geostationary orbit. It is a hell of a lot cheaper and easier to manufacture electric pump fed engines than the r&d and machining costs making turbopumps that can operate reliably in extremely high temperatures. As you stated yourself it is extremely difficult. There are major cost savings in skipping that entire process. Plus due to less mechanical complexity there is a reduced chance of failure. That is worth a lot to people who cannot afford to lose payloads such as university sponsored cubesat launchers and private individuals where the cost alone of a single launch is a big financial hit to them so the data and education factor must be maximized. Don't quote me on this last part but to my knowledge they have better ability to throttle the rocket motors also, which isn't a huge selling factor but for very precise placement it could be a benefit. For very large payloads though I absolutely agree turbopumps are the way to go for now. I certainly do see benefits in electric pump fed rocket motors and I hope the technology is pursued because anything that lowers the cost to entry and complexity of rocketry allows for more competition which is always better. Also I fully respect you are much more experienced and educated than I am in the field as I'm an enthusiast and you're the real deal and I'm not outright disagreeing but it felt like you left out some important aspects of why electric pump fed rocket motors are being used I believe it certainly is more than a marketing gimmick or a failure to produce something else, it appears that Rocket Labs (small correction to your initial statement saying "Electron Labs". Rocket Lab is the company, Electron is just rocket name and there is no company called Electron Labs in the field of rocketry, but I understand what you meant, I just noted it for future reference) is targeting a market of putting small payloads into orbit for as cheap and reliably as possible. If I'm extremely far off base by all means school me, but to me for what it is being used for it doesn't seem like a terrible idea it actually seems like the best option from my viewpoint for its intended payload.

[@BaronLemon]

@@n111254789 Hi Jack. Electric pumps are definitely cheaper and easier to develop and more reliable than turbopumps, but they still do not give the same performance without a large mass penalty; and for this reason, all serious players in the field are still pushing to get and/or develop a turbopump. Of course, it is very likely that, at some point, electric pumps will reach similar energy densities as TPs, and it makes perfect sense to work on them, also. And, for some companies, they could be good enough right now, but the time when they will be the preferred choice (and not because they have no choice) for most companies is not here, yet. Regards!

[@n111254789]

@@BaronLemon For sure I wasn't debating that electric pumps create better thrust to weight ratios. Just the benefits of them. If it costs me 3/4 as much to develop the rocket compared to what someone else spent on r&d and I can hit my target market (for them it was cubesat clusters) then I can run my price lower and ensure that I get the business. Electric pumps can be vastly superior to turbopumps depending on what the rocket is designed for. Payload weight isn't the only thing to consider. Price, securing contracts, and shorter cheaper development times all can net a larger profit faster. Which can then fund the r&d of a turbopump engine putting you in a more comfortable economic situation than just starting with the most difficult option. This is exactly what Rocket Lab has done and it is proving to be a proper business strategy.

[@OCRay1]

Space x is one of the “old established” entities?!

[@guibirow]

SpaceX is 18y old. Compared with other private companies like blue origins, virgin galactic and similar, they are about the same age. Just not old enough like Boeing