Little-spoken propulsion

[Lo.M]

• Well, this topic serves to discuss the means of propulsion that I will quote below. I selected these because they are very little commented.

• Photon rocket: this is an engine that instead of matter uses a flow of electromagnetic radiation to move in space, the simplest variant is basically a sheet of metal heated by a nuclear reactor to other variants, like the one that uses annihilation of a positron and an electron. To this day, I think I only saw one topic about it.

Photon rocket example

• Fission fragment rocket: The fission fragment rocket is a rocket engine design that directly harnesses hot nuclear fission products for impulse, instead of using a separate fluid as the work mass. There are mods that add fragment fission engines, if I remember correctly, it's Far Future Technologies and the nuclear rockets

Fission-fragment propulsion: A fissionable filaments/ B revolving disks/ C Reactor core,/ D fragments exhaust

• Fission fragment sail: fission sail use the natural fission of a radioactive material to generate momentum, it is slow, although it is efficient.

A plastic layer/ B radionuclides layer/ C stopped α particle/ D escaping α particle/ E resulting mean motion/ F neutralizer electron beam

• Antimatter-powered sail: The antimatter candle uses antiprotons to subject a layer of uranium to fission, generating momentum and is a great "spaceship" for making trips to the Kuiper belt region and nearby stars.

• Solar Sail: They are huge sails that take advantage of the pressure exerted by photons coming from the Sun or laser installations 

Solar Sail Models

• Magnetic Sail: Within a planetary magnetosphere, a magnetic sail can push against a planet's magnetic field, especially in an orbit that passes over the planet's magnetic poles, similar to an electrodynamic string. By operating away from planetary magnetospheres, a magnetic sail would force the positively charged protons of the solar wind to bend as they passed through the magnetic field. The impulse change of the protons would push against the magnetic field, and so against the field coil. If a magnetic sail orients at an angle relative to the solar wind, the charged particles are preferably diverted to one side and the magnetic sail is pushed sideways. 

• Electric sail: An electric sail (also known as an electric solar wind sail or E sail) is a proposed form of propulsion of a spacecraft using the dynamic pressure of the solar wind as a buoyancy source. He creates a "virtual" sail using small wires to form an electric field that deflects protons from the solar wind and extracts their momentum

• Plasma magnet sail:  The plasma magnet is a type of magsail that creates an artificial magnetosphere one kilometer wide that diverts the charged solar wind to provide momentum. 

• Electrothermal propulsion: Electrothermal propellers differ from electromagnetic and electrostatic propulsion systems due to their operational design; electromagnetic and electrostatic systems drive charged ions through the use of electric and magnetic fields, while electrothermal systems heat the propellant and depend on thermal dynamics to drive the system

 

• More varied electrostatic propulsion: If one of the things I want most are more varied means of electrostatic propulsion, see ksp 1 only has that "dawn" ion engine.   

 

• Electromagnetic: Electromagnetic propulsion (EMP) is the principle of accelerating an object using an electric current and the flow of magnetic fields. The electric current is used to create an opposite magnetic field or to charge a field, which can then be repelled. When a current flows through a conductor in a magnetic field, an electromagnetic force known as the lorentz force pushes the conductor in a direction perpendicular to the conductor and the magnetic field. This repulsive force is what causes propulsion in a system designed to take advantage of the phenomenon.

• Thermal laser: A laser is left in orbit or on the ground, this laser is fired towards a collector mirror in the spacecraft, which concentrates and directs the laser to a receiver where the hydrogen causes the hydrogen to expand creating an impulse.
   

• Solar thermal rocket (Solar Moth): similar to a thermal laser, in addition to having larger mirrors to concentrate the solar wind instead of the laser. It is only functional until the orbit of ceres (in the case of ksp Dres)

• Oxygen - Aluminum: it is of great interest for any future lunar colonies. Both aluminum and oxygen are readily available in the lunar regoitte, and such a rocket could easily carry out lunar untie, a lunar landing, or an exit from a hypothetical colony.

 

• Fuel: Hydrogen / Helium Atomic: Hydrogen is a common molecule composed of two atoms. This is called hydrogen molecular and is quite stable. If the gas were not a pit composed of molecules, but instead of atoms, you would have hydrogen atomic  This is also called free radical hydrogen>

 

• Bussard Ramjet: A spacecraft that creates huge magnetic fields to deflect the hydrogen molecules that they compress and direct them to a nuclear fusion 

• Medusa: similar to the orion pulse engine, the difference is that the charges are fired in front of the ship in a huge sail in the shape of a parade, the jellyfish has a better absorbency of the explosion.

1-Starting at moment of bomb / pulse unit firing, 2-As the bomb's explosion pulse reaches the parachute canopy, 3-Pushes the canopy, accelerating it away from the bomb explosion as the spacecraft plays out the main tether with the winch, braking as it extends, starting to accelerate the spacecraft, 4-And finally winches the tether back in.

• Thermal antimatter rocket: Thermal antimatter rocket: uses antimatter annihilation to heat and expand some material, for example hydrogen.

Simply the way a thermal antimatter rocket works.

• Pure antimatter rocket: Antiproton annihilation reactions produce charged and uncharged pions, in addition to neutrinos and gamma rays. The charged pions can be channelled by a magnetic nozzle, producing thrust.

• Catalyzed fission/fusion: This is a hybrid approach in which antiprotons are used to catalyze a fission/fusion reaction or to "spike" the propulsion of a fusion rocket or any similar applications.

ICAN-II was a proposed manned interplanetary spacecraft that used the Catalyzed fission/fusion

• Air-augmented rocket: use the supersonic exhaust of some kind of rocket engine to further compress the air collected by the ram effect during flight to use as additional working mass, leading to a more effective boost to any amount of fuel than the rocket or a ramjet alone.

Nuclear thermal rockets (NTR): these are engines that use the heat of a nuclear reactor to heat and expand a fluid and directs to a rocket nozzle. This is a part of topic in contrution. It is probably the most talked about engine I mentioned.

Solid Core: Nuclear thermal rocket/solid core fission. It's a very simple concept. Place a nuclear reactor on top of an exhaust nozzle. Pass hydrogen through it and enter the nozzle.

• Nerva: Nuclear Engine for Rocket Vehicle Applications. The first type of NTR-SOLID propulsion systems. He used reactor fuel rods surrounded by a neutron reflector. Unfortunately its impulse-to-weight ratio is less than one, so no takeoffs with this rocket. Yes I know this already exists in ksp1 plus it could be Adapted/ improved to use hydrogen.

• Class SNRE: The scientists wanted to promote the development of a right-sized solid core nuclear thermal rocket that was as small as possible, but no smaller.  The SNRE class engine has a nozzle skirt that folds into a hinge

• Cermet: Cermet NTR is where the fissionable fuel elements are a mixture composed of fissionable ceramics and a metallic matrix. The problem with the original NERVA fuel elements was that the blown things up were very fragile. They were uranium oxide bars as strong as a thin porcelain plate. Under the vibrations of the rocket flight the stems tended to snap in two.

Credits for image "CERMET": http://large.stanford.edu/courses/2011/ph241/hamerly1/

• DUMBO:  This was a competing project for nerva. Liquid hydrogen propellant enters top and flows through beryllium neutron reflector, cooling it. Flows upward through a Cold Gas Entrance into interior of a reactor tube. Hydrogen seeps through walls of tube, being heated by fissioning uranium. Hot hydrogen escapes through hot gas exit holes in bottom, entering exhaust nozzle.
• 

• Pebble Bed: Nuclear fuel is in the form of a particle bed through which the working fluid is pumped. This allows operation at a higher temperature than the normal solid core reactor, the reactor core is rotated (~ 3000 rpm) on its shaft, such that the fuel bed is centrifuged against the inner surface of a cylindrical wall through which hydrogen gas is injected. 

• Pulsed nuclear thermal rocket:  (Not to be confused with nuclear pulse propulsion), hydrogen is heated by the intense pulses of continuous neutrons (coming from the nuclear reactor) in the channels of the propellant. At the same time, the unwanted energy of the fission fragments is removed by a solitary cooling channel with lithium or other liquid metal. 

 

• Low pressure NTR:  The heating of molecular hydrogen to above 3,000 Kelvin (2726.85 ºC or 4940.33 ºF) will dissolve it into an atomic hydrogen (A single hydrogen atom). Unfortunately at the high pressures commonly used in solid core reactors, the temperature and mass flow of the propellant would combine in a heat stream (remember that heat is the thermal energy flowing from one body to another when there is temperature difference between both) high enough to destroy the reactor. More hopes could we use low pressure? YES, a low pressure NTR has only a 1 bar of pressure (14.5 psi). The disadvantage is the loss of impulse.

• LANTR (LOX-augmented Nuclear Thermal Rocket): This concept involves the use of a "conventional" hydrogen (H2) NTR with oxygen (O2) injected into the nozzle. The O2 injected age as a "postburner" and opera in a "reverse cut jet" mode. This possible becomes to increase (and vary) the impulse.

• MITEE (MInature ReacTor EnginE): A family of small engines ideal for boosters.

Gas core: In this concept we leave uranium in the gaseous state due to very high temperatures, the problem is to prevent that deadly gas from escaping, or at least it is what it should be (cof cof Open cycle NTR cof cof). Most of these engines use Uranium Hexafluoride

• Closed Cycle ( "Nuclear Lightbulb"): In this NTR gas core engine, uranium is properly confined in a fused quartz chamber (Fused Quartz), reaching ABSURD temperatures, the fused quartz this surrounded by hydrogen, and by means of irradiation (since quartz is transparent) it heats hydrogen and expands it into a nozzle. Yes I think you understood the meaning of "Nuclear Lightbulb".

  I wanted to thank you @Wubslin by the picture, this is a mod for ksp if I remember is this: 

KSP Interstellar Extended - Mods - Kerbal Space Program - CurseForge

[1.11.x] Kerbal Atomics: fancy nuclear engines! (December 23, 2020) - Add-on Releases - Kerbal Space Program Forums

 

We can also see here (left to right) a NERVA, and a LANTR 

•  Open Cycle Gas Core: Unlike the previous engine that lets deadly and radioactive radiation escape through the nozzle.  The reaction is maintained in a vortex adapted to minimize the loss of uranium from the nozzle. 

Credits for image: Open Cycle Gas Core

• {...}

Other:

• Liquid Core: A dense high-temperature fluid contains the fissionable material, and the hydrogen propellant is bubbled through being heated. The propellant will be raised to a temperature somewhere between the melting point and boiling of the fluid. The reaction chamber is a cylinder that is rotated to make the molten fluid adhere to the walls, the reaction mass injected radially (cooling the chamber walls) to be heated and expelled out of the exhaust nozzle.

• Droplet core: The most basic design feature of the nuclear ballast of the droplet core is to spray liquid uranium into the core in the form of droplets in the order of five to ten microns in size, to bring the reactor to critical conditions. The liquid uranium fuel ejector is hydrogen driven, and more hydrogen is injected from the reactor side about one and a half feet from the top. High temperature hydrogen is expanded through a nozzle to produce impulse.

• Steam core: It is basically an NTR solid core where solid nuclear fuel elements are replaced by chambers filled with uranium235 tetrafluoride vapor. The uranium fuel is kept physically separate from the hydrogen propellant, so the leakage is not radioactive.

• Radioisotope rocket: This uses the natural decomposition of radioactive elements to generate heat and heat and expand a fuel and directs it to a nozzle.

Ditto spoken of enough that its a mod in KSP 

KSP Interstellar Extended - Mods - Kerbal Space Program - CurseForge

• Colloid-Core:  In this concept, fuel is not a gas, but is a dust storm a Colloid. If you're wondering what a colloid is see this: Colloid - Wikipedia The fuel is a mixture of zirconium carbide with uranium235. This method can solve major problems of ntr gaseous core engines are them: the loss of nuclear fuel and the large size that the engines need.

Spoiler

If you think something is wrong tell me in the comments.

If you think something else should be added, mention it in the comments for me to add.

Crédits: https://nick-stevens.com/  /  http://www.projectrho.com/public_html/rocket/  /   https://en.wikipedia.org/wiki/Main_Page  /  An Analysis of Current Propulsion Systems  /  https : //www.nasa.gov/

 

Edited February 8, 2021 by Lo.M
i'm sorry for any grammar error or some wrong word

[Wubslin]

Man, there are so many opportunities for wacky types of drives. Ever heard of the gas core "nuclear lightbulb" rocket? It's a type of nuclear thermal which is designed to circumvent limitations in materials science in order to reach absolutely insane core temperatures. The core is a gaseous mass of some U-235 containing compound, held supercritical inside double layered quartz bulbs with coolant flowing between the walls. It's important to get the core EXTREMELY hot, such that the bulk of produced heat is radiatively emitted and may pass through the "bulb" walls in order to be absorbed by some propellant which is opaque to the light. Interestingly some artist at NASA had the idea of depicting the outer casing of such an engine as an actual bulb containing many cores, and the design stuck.

There's another technology which I think belongs in the game as a separate component, even if it's not directly related to propulsion technologies. Let's say you've got a big beefy nuclear reactor on your rocket, and you're using some sort of electrically driven propulsion system like an MPD or one of those vaporware VASIMR things propelling your craft. Naturally, you've got a couple of red hot radiators hanging off the side of your vehicle. But why?  The obvious answer is that the sky is a hell of a cold reservoir, and you've got to have some way of rejecting waste heat without having to constantly dump fluid overboard. But a more nuanced answer is that you have some sort of miniaturized closed-cycle heat engine on board which is supplying those radiators with a coolant which is red hot, and I think that should be a part in and of itself. The only other way of extracting huge amounts of electricity is by using Maxwell wizardry to brake charged particles as they come screaming off the griddle in a fusion reactor, but even then there'll be extra heat. Attaching one of these heat plants to a direct capture fusion ramp would be a good way to get even more current out than you already are.

I've been picturing some sort of compact Rankine plant that uses vaporized metal such as NaK as its working fluid and coolant. Practically speaking, this part would be a cylindrical bit, and angrily glowing dual contra-rotating turbines would add to the look of it. It would function a bit like one of those heat collector hubs in the realheat mod but it would generate electricity, and you could either hang radiators directly off of it or else off parts with crossfeed capability. This part could also just be directly integrated with whatever nuclear reactor parts already exist in the game. Or alternately, if separate there could be a multitude of engines which operate at all sorts of temperatures, and using a cooler one (like one of those dinky NASA kilopower stirling jigglers) will provide a longer lifespan but lower power. Food for thought.

 

 

Edited February 9, 2021 by Wubslin
Ultra mega res ugly doodle deleted

[Lo.M]

Edited February 6, 2021 by Lo.M

[Wubslin]

1 hour ago, Lo.M said:

https://wiki.kerbalspaceprogram.com/wiki/LV-N_"Nerv"_Atomic_Rocket_Motor

How is the Nerv anything like a closed cycle rankine plant? If you're running the alternators it means you're actively running out of working fluid and changing your momentum at the same time. All I'm saying is that there needs to be a part where you put in heat and it spits out angry pixies.

[Lo.M]

1 hour ago, Wubslin said:

How is the Nerv anything like a closed cycle rankine plant? If you're running the alternators it means you're actively running out of working fluid and changing your momentum at the same time. All I'm saying is that there needs to be a part where you put in heat and it spits out angry pixies.

Oops... excuse me was the wrong link

3 hours ago, Wubslin said:

Man, there are so many opportunities for wacky types of drives. Ever heard of the gas core "nuclear lightbulb" rocket? It's a type of nuclear thermal which is designed to circumvent limitations in materials science in order to reach absolutely insane core temperatures. The core is a gaseous mass of some U-235 containing compound, held supercritical inside double layered quartz bulbs with coolant flowing between the walls. It's important to get the core EXTREMELY hot, such that the bulk of produced heat is radiatively emitted and may pass through the "bulb" walls in order to be absorbed by some propellant which is opaque to the light. Interestingly some artist at NASA had the idea of depicting the outer casing of such an engine as an actual bulb containing many cores, and the design stuck.

There's another technology which I think belongs in the game as a separate component, even if it's not directly related to propulsion technologies. Let's say you've got a big beefy nuclear reactor on your rocket, and you're using some sort of electrically driven propulsion system like an MPD or one of those vaporware VASIMR things propelling your craft. Naturally, you've got a couple of red hot radiators hanging off the side of your vehicle. But why?  The obvious answer is that the sky is a hell of a cold reservoir, and you've got to have some way of rejecting waste heat without having to constantly dump fluid overboard. But a more nuanced answer is that you have some sort of miniaturized closed-cycle heat engine on board which is supplying those radiators with a coolant which is red hot, and I think that should be a part in and of itself. The only other way of extracting huge amounts of electricity is by using Maxwell wizardry to brake charged particles as they come screaming off the griddle in a fusion reactor, but even then there'll be extra heat. Attaching one of these heat plants to a direct capture fusion ramp would be a good way to get even more current out than you already are.

I've been picturing some sort of compact Rankine plant that uses vaporized metal such as NaK as its working fluid and coolant. Practically speaking, this part would be a cylindrical bit, and angrily glowing dual contra-rotating turbines would add to the look of it. It would function a bit like one of those heat collector hubs in the realheat mod but it would generate electricity, and you could either hang radiators directly off of it or else off parts with crossfeed capability. This part could also just be directly integrated with whatever nuclear reactor parts already exist in the game. Or alternately, if separate there could be a multitude of engines which operate at all sorts of temperatures, and using a cooler one (like one of those dinky NASA kilopower stirling jigglers) will provide a longer lifespan but lower power. Food for thought.

 

I wanted my sketches to look like this.

Second, I think I'm going to include nuclear thermal rockets in the topic.

[Lo.M]

The translation problem has already been resolved.

[Lo.M]

Updated

[Lo.M]

I'll add other things to the topic.

Does anyone have an idea of any engine/means of propulsion that can be added to this topic?

 

[Wubslin]

6 hours ago, Lo.M said:

I'll add other things to the topic.

Does anyone have an idea of any engine/means of propulsion that can be added to this topic?

 

I got some!

Low pressure nuclear thermal

O2 afterburning NTR

Air-augmented ramrockets

Mass drivers

 

[Lo.M]

1 hour ago, Wubslin said:

I got some!

Low pressure nuclear thermal

O2 afterburning NTR

Air-augmented ramrockets

Mass drivers

 

OK I do that tomorrow. (Here where I live it is very late)

Edited February 7, 2021 by Lo.M

[Wubslin]

4 hours ago, Lo.M said:

OK I do that tomorrow. (Here where I live it is very late)

I wouldn't feel the need to integrate them into the OP. Don't worry about it

[Guest]

An O2 afterburning NTR would be very cool. You’d get the Isp of a NTR with the TWR of a chemical rocket. Only problem is that it would be too good – if that’s available, why use anything else? (Radiation security not being a concern in kerbal-universe.)

[Wubslin]

3 hours ago, Brikoleur said:

An O2 afterburning NTR would be very cool. You’d get the Isp of a NTR with the TWR of a chemical rocket. Only problem is that it would be too good – if that’s available, why use anything else? (Radiation security not being a concern in kerbal-universe.)

It's not that good. For the same afterburning NTR, hauling 80 tons of H2 and 20 tons of O2 won't give you as much delta-v as just 100 tons of H2 by itself. And considering the game is going to allow timewarp during burns I don't care nearly as much about TWR any more.

For me at least, after parking orbit insertion there are only two things that make me care about TWR:

1. Patience. who can be bothered with a 20 minute burn? I sure can't, lol. But with burn timewarp in KSP 2 all of a sudden I can!

2: Gravity losses. I like to do periapse passes to minimize gravity losses when doing interplanetary transfers, but there comes a dreaded point where at some point you almost reach escape velocity. What happens when you need 1,000 m/s of hyperbolic excess velocity on top of escape velocity to get to Eeloo or whatever? Before, you maybe were racking up 100 m/s of additional speed with each periapse pass. But that took two whole minutes each time! And now not only is this going to be the last pass you'll get before escaping Kerbin SOI altogether, it'll be the quickest of them all. You might have maybe one minute where prograde is within 10 degrees of the horizon.

So you do what you can do, and that's burn. But skating up that hyperbola you start to find yourself pitching further and further up to match prograde. Before you know it, the vast majority of your ship's acceleration vector is directly fighting Kerbin's pull - you're dumping fuel straight down the well. For all the good it's doing you may as well be on the pad piddling your fuel away at 1% throttle. These are the cases where TWR is important. So what an O2 afterburner may be good for, is ensuring that the last pass you do really squeezes off that 1,000 m/s as fast and painlessly as possible. That's not necessarily a benefit all the time, though. In orbit of Kerbol or something, every NTR burn might as well be considered instantaneous and that O2 is just dead weight where H2 could be. Use the right tool for the job, right?

[Guest]

Perhaps I should have clarified -- I meant that afterburning NTRs would effectively obsolete chemical rockets. In the current tech tree, most chemical rockets remain viable for the entire game -- you still need them for launchers and landers, where TWR is critical, even if you switch to Nervs for interplanetary transfer stages. If a selection of AB-NTRs at various sizes was available, when would you ever want to use a chemical rocket? You've got the Isp when you need it, and you've got the TWR when you need it, all in one tidy package.

(I suppose the added dry mass of the reactor would leave niches for chemical rockets here and there, but for the most part...)

[Lo.M]

Updated

[KerikBalm]

23 hours ago, Brikoleur said:

An O2 afterburning NTR would be very cool. You’d get the Isp of a NTR with the TWR of a chemical rocket. Only problem is that it would be too good – if that’s available, why use anything else? (Radiation security not being a concern in kerbal-universe.)

I have said the same thing about a certain engine type that will be in ksp2, which doesn't even have scientific backing.

Also, if ksp2 models radiation, it doesn't obsolete chemical

[Lo.M]

The topic has been updated.

[Starhelperdude]

6 hours ago, KerikBalm said:

I have said the same thing about a certain engine type that will be in ksp2, which doesn't even have scientific backing.

Also, if ksp2 models radiation, it doesn't obsolete chemical

oh oh

I know which metallic form of which element you mean

Spoiler

metallic nitrogen!

 

[Lo.M]

17 minutes ago, Starhelperdude said:

nitrogênio metálico!

17 minutes ago, Starhelperdude said:

metallic nitrogen!

[KerikBalm]

On 2/4/2021 at 6:12 PM, Lo.M said:

• Photon rocket: this is an engine that instead of matter uses a flow of electromagnetic radiation to move in space, the simplest variant is basically a sheet of metal heated by a nuclear reactor to other variants, like the one that uses annihilation of a positron and an electron. To this day, I think I only saw one topic about it.

If its not antimatter or some sort of handwaved tech, it doesn't make sense. If using a nuclear reaction to provide the energy for the photons, you are left with spent fuel mass from which no further energy can be extracted. It would be much more efficient to chuck that out the back at high speed. Much more thrust for the same amount of fuel

Quote

• Thermal laser: A laser is left in orbit or on the ground, this laser is fired towards a collector mirror in the spacecraft, which concentrates and directs the laser to a receiver where the hydrogen causes the hydrogen to expand creating an impulse.
  ...

• Solar thermal rocket (Solar Moth): similar to a thermal laser, in addition to having larger mirrors to concentrate the solar wind instead of the laser. It is only functional until the orbit of ceres (in the case of ksp Dres)

I recently made a thread about this, wanting beamed power propulsion, possibly with variants that could work independently close to a star for added gameplay options

Quote

• Fuel: Hydrogen / Helium Atomic: Hydrogen / Helium is a common molecule composed of two atoms. This is called hydrogen / molecular helium and is quite stable. If the gas were not a pit composed of molecules, but instead of atoms, you would have hydrogen / atomic helium. This is also called free radical hydrogen / helium.

Helium is not a common molecule composed of 2 atoms, atomic helium is just helium. What you describe does work for Hydrogen though.

The issue is that it is very unstable, but at least for this form of hydrogen, you can supercool it and have a mixture of up to 15% atomic hydrogen in 85% liquid hydrogen... in this case you get a very powerful chemical propulsion (>700 Isp), giving you Nuclear thermal performance without the nuclear.

However, this stuff would be like working with nitroglycerin, it would not take much to set it off, and a cooling failure would have catastrophic results

However, atomic hydrogen fuel is still wayyyyyy wayyy wayy more plausible than metallic hydrogen as a fuel.

 

Quote

• Nuclear Thermal Rockets: It is a nuclear reactor where the propellant is the refrigerant and instead of a cooling tower the propellant is directed to an exhaust nozzle. It is probably the most talked about engine I mentioned.

*cough* LV-N *cough*

Quote

• Medusa: similar to the orion pulse engine, the difference is that the charges are fired in front of the ship in a huge sail in the shape of a parade, the jellyfish has a better absorbency of the explosion.

Yea, I was wondering if it might be in KSP2, just not shown yet, as a more advanced variant of the Orion drive

Quote

• Thermal antimatter rocket: Thermal antimatter rocket: uses antimatter annihilation to heat and expand some material, for example hydrogen.

Honestly, this is the only version that would work. A pure matter-antimatter rocket would have utterly ridonculous waste heat levels.

Plus it still can give amazing performance.

Quote

• Pure antimatter rocket: Antiproton annihilation reactions produce charged and uncharged pions, in addition to neutrinos and gamma rays. The charged pions can be channelled by a magnetic nozzle, producing thrust.

Often thought to be the torch ship drive in KSP2

Quote

• Air-augmented rocket: use the supersonic exhaust of some kind of rocket engine to further compress the air collected by the ram effect during flight to use as additional working mass, leading to a more effective boost to any amount of fuel than the rocket or a ramjet alone.

I have talked about these so many times... yes, I want some

Quote

• LANTR (LOX-augmented Nuclear Thermal Rocket): This concept involves the use of a "conventional" hydrogen (H2) NTR with oxygen (O2) injected into the nozzle. The O2 injected age as a "postburner" and opera in a "reverse cut jet" mode. This possible becomes to increase (and vary) the impulse.

Look at Porkjets parts pack, he's got a LANTR in there. Also I want it, if KSP2 has mmH engines but not this, its a travesty.

Quote

Gas core: In this concept we leave uranium in the gaseous state due to very high temperatures, the problem is to prevent that deadly gas from escaping, or at least it is what it should be (cof cof Open cycle NTR cof cof). Most of these engines use Uranium Hexafluoride

• Closed Cycle ( "Nuclear Lightbulb"): In this NTR gas core engine, uranium is properly confined in a fused quartz chamber (Fused Quartz), reaching ABSURD temperatures, the fused quartz this surrounded by hydrogen, and by means of irradiation (since quartz is transparent) it heats hydrogen and expands it into a nozzle. Yes I think you understood the meaning of "Nuclear Lightbulb".

"little spoken" - yet there you have it (and the LANTR) as a mod in KSP

Quote

  Radioisotope rocket: This uses the natural decomposition of radioactive elements to generate heat and heat and expand a fuel and directs it to a nozzle.

 

Ditto spoken of enough that its a mod in KSP

 

32 minutes ago, Starhelperdude said:

I know which metallic form of which element you mean

  Hide contents

metallic nitrogen!

 

Well, I didn't specify metallic, but yes I was thinking of a certain metallic element.

FYI, metallic Nitrogen is a thing, and its not metastable either

Edited February 8, 2021 by KerikBalm

[Lo.M]

22 minutes ago, KerikBalm said:

Helium is not a common molecule composed of 2 atoms, atomic helium is just helium. What you describe does work for Hydrogen though.

The issue is that it is very unstable, but at least for this form of hydrogen, you can supercool it and have a mixture of up to 15% atomic hydrogen in 85% liquid hydrogen... in this case you get a very powerful chemical propulsion (>700 Isp), giving you Nuclear thermal performance without the nuclear.

However, this stuff would be like working with nitroglycerin, it would not take much to set it off, and a cooling failure would have catastrophic results

However, atomic hydrogen fuel is still wayyyyyy wayyy wayy more plausible than metallic hydrogen as a fuel.

Thanks i'll get it right

22 minutes ago, KerikBalm said:

*cough* LV-N *cough*

Yes I know this already exists in ksp1 plus it could be Adapted/ improved to use hydrogen.

Edited February 8, 2021 by Lo.M