[1.0.5] Atomic Age - Nuclear Propulsion - Red Hot Radiators

[FreeThinker]

I don't think KSPI users need any more engines from other mods except for atmospheric usage.

I'm curious, what do you mean by that?

[Eleven]

Does anyone have a MM patch to make the fuel switcher work with the tanks from MRS and SpaceY Lifters?

(EDIT) I'm a noob but this was pretty easy to figure out, so here is the relevant info if anyone wants to use the Fuel Switcher with MRS and/or SpaceY tanks:

MRS/SpaceY configs

Edited March 6, 2015 by Eleven

[bakanando]

I love the 2.5m engine, great design.

[Threadsinger]

Very, very awesome. I'd love to see your take on a theoretical, "unproven" design like a fusion engine, or a wierder ion engine. But excellent gameplay balance (and a really cool model!), I shall add it alongside the NFT, KSPI, and USI drives that I use with equal pride.

[hieywiey]

PorkJet, are you going to keep working on your hab mod, or have you moved on?

[Nothalogh]

@PorkJet

Is there a reason for the extreme amount of gimballing on the Gas Core NTR?

[sashan]

Well, my interplanetary ships are often unbalanced, i.e. have a lander or a capsule docked to the side.

[WuphonsReach]

I wish the engine-only pack included the Nuclear Lightbulb (Closed Cycle Gas-Core), instead it only includes the LV-Nc engine.

[zilfondel]

Great engine pack! Really been having a lot of fun with the nuclear lightbulb. It seems well balanced, in that its massive tonnage offsets its incredible efficiency and decent thrust. I made a '3-stage to anywhere' ship that gets you to LKO with almost 6,000 delta-V left over. It can land almost anywhere in the solar system and return to Kerbin (Laythe and Eve being exceptions).

It can also land partially propulsively on Kerbin or Duna with the help of a chute.

[zilfondel]

FYI, I posted a giffy of the rocket above crashing on Minmus, and some redditors pointed out that its gimbal is extremely fast.

I added these to the part cfg file:

gimbalResponseSpeed = 2

useGimbalResponseSpeed = true

under the Gimbal Module, and it really smoothed out the animation for the part. Its a lot less jerkier animation, but still allows a good response from the controls. Porkjet, I would recommend adding this to the download.

[Nothalogh]

its gimbal is extremely fast

Yeah, in my experimentation with it I've taken to just locking the gimbals.

That being said, it's a fookin masterpiece, especially on an interplanetary hauler, it's like the heavy diesel engine of the rocket world

[Treble Sketch]

I've been looking for this ever since I saw your rocket engine on a Nuclear Rockets website...

Thanks ^^

Plus, I think this mod should be indexed in CKAN ^^

[ChrisSpace]

Hello, just wanted to say how much I have enjoyed this mod, as well as make a few suggestions

- the lightbulb's TWR is a bit too high, the engine it is based on had more mass and slightly less thrust. this could be counteracted gameplay-wise by bringing the isp up to match its real counterpart

- perhaps the isp of the LV-N could be changed to match its real counterpart (825s in vaccum, 380s at sea level), and its mass increased to balance its overpowered TWR. I know the LV-N is stock, but there should be a way to reconfig this, or something

- similar suggestion for the LANTERN

- vapor-core, liquid-core, and most notably, open cycle gas-core nuclear engines

- compatibility with near future propulsion, ie engines that can run off liquid hydrogen

[FreeThinker]

- perhaps the isp of the LV-N could be changed to match its real counterpart (825s in vaccum, 380s at sea level), and its mass increased to balance its overpowered TWR. I know the LV-N is stock, but there should be a way to reconfig this, or something

No, keep it, it's in a higher technode which allows it to have higher performace.

note that liquid hydrogen is going to be replaced by LqdHydrogen by all CRP mods (including NFT)

Edited April 13, 2015 by FreeThinker

[lajoswinkler]

Will the mod ever be repaired to account for realistic temperature distribution as sashan described here?

One thing everyone misses while making emissives - actually, exhaust is cooled as it goes through the nozzle. That means the hottest part is the combustion chamber, or reactor for NTR's. Well, it is usually actively cooled, so that would be the throat, the narrowest part which is the hottest.

Here's the inside tempratures for NERVA, the stock emissive is pretty much correct:

http://www.intechopen.com/source/html/42786/media/image23.jpeg

Here's the usual liquid fuel engine (look to the left):

http://cs.astrium.eads.net/sp/launcher-propulsion/analytical-engineering/images/18g.jpg

Aside from that... Great mod! Pity I'm out of RAM on my ancient crap.

[futrtrubl]

Will the mod ever be repaired to account for realistic temperature distribution as sashan described here?

While that is all true the chamber and throat are often actively cooled with fuel and in fact you can see the piping in the models for that active cooling.

[lajoswinkler]

Even if it's cooled, it will always be hotter than the nozzle.

[Hotblack Desiato]

very nice mod, I think I'm going to use it in the 1.0 installation.

and I have a feature-request (shouldn't be difficult): lots of people already asked for LH2 support for near future prop. I'd like to ask if you can add the requirement for enriched uranium and nuclear waste? because I'm playing with extraplanetary launchpads and building a nerva engine including the nuclear fuel out of plain metal/rocketparts seems to be odd. it just needs two extra tanks for enriched uranium and nuclear waste (or whatever name they use) and should slowly burn through the nuclear fuel.

[Gkirmathal]

@Desiato, solid core ntr type engines have their nuclear fuelrods enclosed within the engine's reactor.

External seperate fuel tanks is not how these engines work.

Liquid or gascore could be different, but I personally havent found a lot of Info on reactor refueling subject.

Yesterday I made a quick module manager cfg edit, adding a Uranium fuel quantity to the bl40n and made it a generator when the engine is off. It worked, full burn to Duna consumed 20% of the 12.0 in the engine.

I can post the cfg is anyone wants to experiment with it.

[futrtrubl]

Even if it's cooled, it will always be hotter than the nozzle.

The reaction mass will be for sure, that's true for all rockets. For the outside of the throat material no. You can see in this picture the cooled throat doesn't glow

That's non-nuclear but it still applies. Chamber and throat pressures are higher and so the containing material can't get as hot.

Edited April 14, 2015 by futrtrubl

[Hotblack Desiato]

@Desiato, solid core ntr type engines have their nuclear fuelrods enclosed within the engine's reactor.

External seperate fuel tanks is not how these engines work.

Liquid or gascore could be different, but I personally havent found a lot of Info on reactor refueling subject.

Yesterday I made a quick module manager cfg edit, adding a Uranium fuel quantity to the bl40n and made it a generator when the engine is off. It worked, full burn to Duna consumed 20% of the 12.0 in the engine.

I can post the cfg is anyone wants to experiment with it.

I'd be interested. does it also produce waste?

and yes, I do know that they don't really work this way. but as explained above, they also can't be just made out of metal and nothing else, and it feels cheaty having a rocket which has a superb specific impulse without the downside of a special fuel. I do know that these rocket-motors are supposed to be fabricated on kerbin, and they can add whatever they want, but in a space station, there have limited supplies.

[lajoswinkler]

The reaction mass will be for sure, that's true for all rockets. For the outside of the throat material no. You can see in this picture the cooled throat doesn't glow http://images.spaceref.com/news/2010/ooSF99058.jpg

That's non-nuclear but it still applies. Chamber and throat pressures are higher and so the containing material can't get as hot.

I see a huge difference between that photo and this picture.

The highest temperature is always where the reaction takes place. In case of chemical rockets it's the chamber where highest pressure is. In case of nuclear rockets it's the nuclear reactor core.

My point is - the end of the nozzle can not possibly be hotter than its neck.

[Starwaster]

I'd be interested. does it also produce waste?

and yes, I do know that they don't really work this way. but as explained above, they also can't be just made out of metal and nothing else, and it feels cheaty having a rocket which has a superb specific impulse without the downside of a special fuel. I do know that these rocket-motors are supposed to be fabricated on kerbin, and they can add whatever they want, but in a space station, there have limited supplies.

The engines as configured have Isp that is excessive for stock fuels. Isp that high requires something like hydrogen. (speaking of LF only, not LFO)

The reactors tested as part of project rover could be said to produce 'waste' but that was because the fuel rods suffered heavy erosion. As far as I know that problem was solved through the use of special coatings and/or fuel rod materials and would be eliminated in flight ready production models. (or mostly eliminated)

Anyway, what he said is about right; it doesn't make sense for the nuclear fuel to be in external tanks. The engine contains the nuclear fuel (it is a fission reactor not just a rocket motor) and that would last for years regardless of whether it is used or not. Whether that feels 'cheaty' or not, that's how they really work.

You should check out Real Fuels + Raptor's stockalike configurations. The nuclear engine that is in Raptor's pack has a configuration that adds nuclear fuel + nuclear waste and it deteriorates over time though in actual game play, I find haven't yet run into a situation where that mattered to game play because I never had any engine long enough to exhaust its nuclear fuel. Additionally, they can be configured for a variety of propellants with appropriate Isp and thrust levels for each one. Propellants are hydrogen, methane and ammonia. Water was in at one point but it got removed. (too bad, water is a very reasonable propellant and through ISRU more plentiful than in our own solar system)

[futrtrubl]

The highest temperature is always where the reaction takes place. In case of chemical rockets it's the chamber where highest pressure is. In case of nuclear rockets it's the nuclear reactor core.

My point is - the end of the nozzle can not possibly be hotter than its neck.

And yet it is. As you have said the hottest (reactionmass) is the chamber and throat of a rocket whether it is nuclear or chemical. However I can not find a single picture of a rocket with a throat or chamber that is brighter than the bell.

[Starwaster]

And yet it is. As you have said the hottest (reactionmass) is the chamber and throat of a rocket whether it is nuclear or chemical. However I can not find a single picture of a rocket with a throat or chamber that is brighter than the bell.

probably because the exhaust carries most of the heat away and the nozzle is regeneratively cooled but that's been said already hasn't it