Nuclear fusion firm Pulsar fires up a UK-built hybrid rocket engine
(2021/11/26)
- Reference: 1637940005
- News link: https://www.theregister.co.uk/2021/11/26/pulsar_engine/
- Source link:
UK nuclear fusion outfit Pulsar Fusion has fired up a chemical rocket engine running on a combination of nitrous oxide oxidiser, high-density polyethylene fuel and oxygen.
The acceptance tests of the UK-built rocket were conducted at [1]COTEC , a UK Ministry of Defence site at Salisbury Plain in southern England.
We spoke to CEO of the company, Richard Dinan, [2]in 2018 , when he discussed the prospects for fusion power, and the use of the technology for space travel as well as electricity generation. [3]In 2020 he was showing off an ion thruster with plasma running at several million degrees and particles fired at speeds over 20km per second.
[4]
Pulsar Fusion engine (click to enlarge). Pic: Pulsar Fusion
This month it is the turn of chemical rockets, which are still required in order to get from Earth to orbit (although [5]SpinLaunch and its impressive accelerator are worthy of mention, having conducted a first vertical test of the [6]rotational launch system in October .)
"What I've learned," Dinan told The Reg , "is that everybody knows how rocket engines work. Lots and lots of people are rocket engine experts. But none of these people can build rocket engines. The people that can build rocket engines are the people that have taken apart 20 engines that have failed..."
[7]UK Space ponders going nuclear with Rolls-Royce: Hopes are to slice the time it takes for space travel
[8]Fusion boffins apply plasma know-how to building thrusters
[9]Need electric propulsion for your satellite? Want a 'made in Britain' sticker? Step right this way...
[10]Brit startup plans fusion-powered missions to the stars
Following repeated redesigns "the first test was positive!" said Dinan, "It didn't explode and the flames came out of the right end."
We test fired our first hybrid rocket engine earlier this week.
A great result for our first trials using HDPE/N2O fuels. [11]pic.twitter.com/vsnVPDfzEm — Richard Dinan (@RichardDinan) [12]November 22, 2021
Thrust-wise, the relatively small engine was restricted to five kN during the test although Dinan told us the target was to get to 100kN as development progresses. By way of comparison, the Rutherford engine of Rocket Lab, nine of which power the first stage of its Electron booster, produces 24kN at sea-level while the Merlin engine of SpaceX's Falcon 9 will go to 854kN.
Unlike Rocket Lab's and SpaceX's powerplants, Pulsar's hybrid engine runs on high-density polyethylene fuel and oxygen. An oxidiser is required to make the magic happen. The fuels themselves are described as non-toxic and failure modes should be relatively benign if things go wrong (compared to traditional liquid-fuelled engines.)
[13]
Pulsar has no intention of building a rocket itself, preferring instead to sell the home-grown tech as an alternative to US options (often hamstrung by export restrictions). The same applies to its Hall Effect Thruster (HET), for which UK government funding was received in September. Dinan told us the HET units had just passed a 20G vibration test at another UK facility and have a slot booked in 2023 for an in-orbit demonstration.
[14]
"I think we can do better than that," he said, in relation to the vibration test.
Fusion power remains an ambition for the future for Dinan although the addition of the hybrid rocket engine technology as well as the ion thruster gives the company some options and may attract interest from industry.
[15]
"If we could say 'We've built and tested satellite engines, and they work and we've built and tested launch engines, and they work... Now we want to build a fusion engine...' it makes us more credible."
A first prototype of such an engine is currently expected for 2025. ®
Get our [16]Tech Resources
[1] http://www.cotec.org.uk/salisbury-plain.php
[2] https://www.theregister.com/2018/10/01/fusion/
[3] https://www.theregister.com/2020/08/25/fusion_thrusters/
[4] https://regmedia.co.uk/2021/11/25/pulsar.jpg
[5] https://www.spinlaunch.com/
[6] https://www.spinlaunch.com/suborbital#p4
[7] https://www.theregister.com/2021/01/12/uk_space_ponders_going_nuclear/
[8] https://www.theregister.com/2020/08/25/fusion_thrusters/
[9] https://www.theregister.com/2018/11/01/uk_ion_drive/
[10] https://www.theregister.com/2018/10/01/fusion/
[11] https://t.co/vsnVPDfzEm
[12] https://twitter.com/RichardDinan/status/1462711984919613443?ref_src=twsrc%5Etfw
[13] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=2&c=2YaESvqlFr-2jLW3EFp8DlAAAABQ&t=ct%3Dns%26unitnum%3D2%26raptor%3Dcondor%26pos%3Dtop%26test%3D0
[14] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=4&c=44YaESvqlFr-2jLW3EFp8DlAAAABQ&t=ct%3Dns%26unitnum%3D4%26raptor%3Dfalcon%26pos%3Dmid%26test%3D0
[15] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=4&c=44YaESvqlFr-2jLW3EFp8DlAAAABQ&t=ct%3Dns%26unitnum%3D4%26raptor%3Dfalcon%26pos%3Dmid%26test%3D0
[16] https://whitepapers.theregister.com/
The acceptance tests of the UK-built rocket were conducted at [1]COTEC , a UK Ministry of Defence site at Salisbury Plain in southern England.
We spoke to CEO of the company, Richard Dinan, [2]in 2018 , when he discussed the prospects for fusion power, and the use of the technology for space travel as well as electricity generation. [3]In 2020 he was showing off an ion thruster with plasma running at several million degrees and particles fired at speeds over 20km per second.
[4]
Pulsar Fusion engine (click to enlarge). Pic: Pulsar Fusion
This month it is the turn of chemical rockets, which are still required in order to get from Earth to orbit (although [5]SpinLaunch and its impressive accelerator are worthy of mention, having conducted a first vertical test of the [6]rotational launch system in October .)
"What I've learned," Dinan told The Reg , "is that everybody knows how rocket engines work. Lots and lots of people are rocket engine experts. But none of these people can build rocket engines. The people that can build rocket engines are the people that have taken apart 20 engines that have failed..."
[7]UK Space ponders going nuclear with Rolls-Royce: Hopes are to slice the time it takes for space travel
[8]Fusion boffins apply plasma know-how to building thrusters
[9]Need electric propulsion for your satellite? Want a 'made in Britain' sticker? Step right this way...
[10]Brit startup plans fusion-powered missions to the stars
Following repeated redesigns "the first test was positive!" said Dinan, "It didn't explode and the flames came out of the right end."
We test fired our first hybrid rocket engine earlier this week.
A great result for our first trials using HDPE/N2O fuels. [11]pic.twitter.com/vsnVPDfzEm — Richard Dinan (@RichardDinan) [12]November 22, 2021
Thrust-wise, the relatively small engine was restricted to five kN during the test although Dinan told us the target was to get to 100kN as development progresses. By way of comparison, the Rutherford engine of Rocket Lab, nine of which power the first stage of its Electron booster, produces 24kN at sea-level while the Merlin engine of SpaceX's Falcon 9 will go to 854kN.
Unlike Rocket Lab's and SpaceX's powerplants, Pulsar's hybrid engine runs on high-density polyethylene fuel and oxygen. An oxidiser is required to make the magic happen. The fuels themselves are described as non-toxic and failure modes should be relatively benign if things go wrong (compared to traditional liquid-fuelled engines.)
[13]
Pulsar has no intention of building a rocket itself, preferring instead to sell the home-grown tech as an alternative to US options (often hamstrung by export restrictions). The same applies to its Hall Effect Thruster (HET), for which UK government funding was received in September. Dinan told us the HET units had just passed a 20G vibration test at another UK facility and have a slot booked in 2023 for an in-orbit demonstration.
[14]
"I think we can do better than that," he said, in relation to the vibration test.
Fusion power remains an ambition for the future for Dinan although the addition of the hybrid rocket engine technology as well as the ion thruster gives the company some options and may attract interest from industry.
[15]
"If we could say 'We've built and tested satellite engines, and they work and we've built and tested launch engines, and they work... Now we want to build a fusion engine...' it makes us more credible."
A first prototype of such an engine is currently expected for 2025. ®
Get our [16]Tech Resources
[1] http://www.cotec.org.uk/salisbury-plain.php
[2] https://www.theregister.com/2018/10/01/fusion/
[3] https://www.theregister.com/2020/08/25/fusion_thrusters/
[4] https://regmedia.co.uk/2021/11/25/pulsar.jpg
[5] https://www.spinlaunch.com/
[6] https://www.spinlaunch.com/suborbital#p4
[7] https://www.theregister.com/2021/01/12/uk_space_ponders_going_nuclear/
[8] https://www.theregister.com/2020/08/25/fusion_thrusters/
[9] https://www.theregister.com/2018/11/01/uk_ion_drive/
[10] https://www.theregister.com/2018/10/01/fusion/
[11] https://t.co/vsnVPDfzEm
[12] https://twitter.com/RichardDinan/status/1462711984919613443?ref_src=twsrc%5Etfw
[13] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=2&c=2YaESvqlFr-2jLW3EFp8DlAAAABQ&t=ct%3Dns%26unitnum%3D2%26raptor%3Dcondor%26pos%3Dtop%26test%3D0
[14] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=4&c=44YaESvqlFr-2jLW3EFp8DlAAAABQ&t=ct%3Dns%26unitnum%3D4%26raptor%3Dfalcon%26pos%3Dmid%26test%3D0
[15] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=4&c=44YaESvqlFr-2jLW3EFp8DlAAAABQ&t=ct%3Dns%26unitnum%3D4%26raptor%3Dfalcon%26pos%3Dmid%26test%3D0
[16] https://whitepapers.theregister.com/
Smart move
tony72
The market for launch vehicle already seems to be getting really crowded, and one feels there's going to be a major shakeout at some point. But focusing on components for rockets seems like a smart move.
Strange though, this polyethylene/lox engine doesn't seem to be mentioned anywhere on Pulsar Fusion's website, and all I can find on it online is articles with pretty much the same info as this Reg article, presumably all based on the same press release. The only mob I can think of that's flying hybrid solid fuel engines is Virgin Galactic, I wonder if these are comparable.
Fusion rocket engines - the gist
Starting with hybrid engines, later evolving into fusion ones. Interesting.
Although it is PLAINLY obvious that a proper fusion-powered rocket engine would maximize efficiency, it will still need "a something" to fling out of the tailpipe at high velocity, as does the ion engine.
I suppose there are many ways of "flinging" but the only way I can think up looks a LOT like a standard engine, but 90% of the gamma+neutrons from the reaction would be absorbed by some hydrogenous liquid, like water, methane, or ammonia [which happen to be pretty abundant in our solar system] and then be expelled out the back end like regular rocket exhaust. "Impulse engine"
Current rocket tech runs at a temperature close to melting the engines for max efficiency and single-use. Obviously we want the re-usable kind. So efficiency MIGHT have to suffer a bit. Unless... you use the propulsion fluid itself to MAKE A LAMINAR BOUNDARY LAYER on the insides of the engine! It's something related to what is already being done, i.e. use fuel to cool the rocket nozzle. In any case some clever spark will hopefully come up with a design that captures as much energy from the fusion reaction as possible, and THEN flings it out the back in a way that maximizes utilization of kinetic energy (proportional to v-squared, how much energy is needed) and momentum (mass times velocity, and how you get thrust) along with fuel weight/mass and the overall weight/mass of the rocket itself.
(An ideal ratio of fuel use vs thrust vs reactor capacity just has to exist)
Anyway, just thought I'd mention that. Looking forward to something that ACTUALLY WORKS. 2025 - was that for the FUSION engine?
NOTE: a distance of about 30cm in liquid water is sufficient to absorb about 90% of gamma, and about 1 meter for 90% of neutrons. SO you would need an engine large enough to have the equivalent of liquid "that thick" to absorb most of the radiation and generate propulsion. The logistics of the placement of the fusion reaction itself might be the hardest part, but if you can just get most of that radiation into a hydrogenous liquid with a cooling layer protecting the metal parts, you SHOULD be able to get some very efficient thrust out of a reasonably sized engine.