[1.12.x] Kerbal Atomics: fancy nuclear engines! (August 18, 2024)

[Nertea]

KSP 1.12.x

Kerbal Atomics [1.3.4]  Last Updated August 18, 2024

This part pack is designed to provide some new nuclear thermal rockets for your spaceship-building pleasure. There are eight new engines, one in the 3.75m size class, four in the 2.5m size class, two in the 1.25m size class and one in the 0.625m size class. They are fuelled with LiquidHydrogen, and in some cases can use Oxidizer to boost their thrust at the cost of specific impulse. Liquid Hydrogen is less dense than liquid fuel, so for the same Delta-V, you will need more tank volume. 

To store your liquid hydrogen fuels, I've provided ModuleManager/B9PartSwitch configs that allow you to change the contents of stock tanks between LF/O, LH2/O, LF, O and LH2. These should work with most mod tanks, but no promises. However, Liquid Hydrogen is very temperamental and without the proper storage it will slowly evaporate ("boil off"). Therefore, I provide special cryogenic tanks bundled with the mod, that use a small amount of Electric Charge to stop the evaporation.

This mod is designed to synergize well with Cryogenic Engines, and with the various Near Future Technologies mods I make. It is also fully integrated into the Community Tech Tree.

Full Screenshot Gallery

Frequently Asked Questions Q: RealFuels support? A: Talk to RealFuels people, not my issue. Q: Oxidizer isn't LOX, it's something else! A: You are completely free to do whatever you like and change it  Q: How do I stop the engines from using LH2 and use LF instead? A: Install the NTRsUseLF patch in the Extras folder.  Q: Why can't I refuel the Emancipator? A: It's a cheaty engine. It has a disadvantage. If you want to refuel it, you need to download NF Electrical and install the high complexity reactor integration patch.

Licensing All code and cfgs are distributed under the MIT License All art assets (textures, models, animations) are distributed under an All Rights Reserved License. All bundled mods are distributed under their own licenses.

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Primary (SpaceDock) Secondary (CurseForge) Tertiary (GitHub)

Issue Tracking and Source

If you appreciate this project, please consider contributing to my caffeine addiction! I really appreciate it, and also helps justify this time sink to my wife , which results directly in more models. 

[smjjames]

Another Nertea mod, awesome!

Also, is the boil-off something that can be made optional?

[Nertea]

Next release will include a few classic "extras" patches, for example to disable boiloff and to convert these engines to LF in a similar fashion to CryoEngines' extras. 

In the meantime you could remove the boiloff modules in the configs via MM patch or direct editing.

[Jimbodiah]

Congrats Nertea!!! Another great mod!!!

[Captain Sierra]

My followed thread list is getting a bit longer with these things ....

 

Also @Nertea is there plans to bring back the LH2 conversion for other NTR mods such as Atomic Age, now balanced against this mod instead of being part of NFT?

[Nertea]

Its included in the download, not heavily tested though.

[Whirligig Girl]

Is that an open cycle Gas Core NTR? Because if so, wow. We need a mod that makes Kerbalkind *hate* you (reputation drop) if you use this in the atmosphere. Open cycle gas core NTRs are notorious for spewing hot radioactive death out of their nozzles. By comparison, the Closed Cycle "Nuclear Lightbulb" NTR is far less deadly, and will only release hot radioactive death if it explodes or something, which is probably true of most NTRs. Downside is of course lower Isp and TWR.

 

EDIT: stop liking this, I was wrong.

Edited March 28, 2017 by GregroxMun

[billkerbinsky]

1 minute ago, GregroxMun said:

Is that an open cycle Gas Core NTR? Because if so, wow. We need a mod that makes Kerbalkind *hate* you (reputation drop) if you use this in the atmosphere. Open cycle gas core NTRs are notorious for spewing hot radioactive death out of their nozzles. By comparison, the Closed Cycle "Nuclear Lightbulb" NTR is far less deadly, and will only release hot radioactive death if it explodes or something, which is probably true of most NTRs. Downside is of course lower Isp and TWR.

Also should include StageRecovery-like hook that penalizes you if anything nuclear-powered crashes and/or burns on the surface of Kerbin.   Besides reputation, I'd expect it to immediately cost cash (for cleanup & decontamination), as well as increased part cost..    And if you drop it in or around KSC, you might have to wait for any short-lived isotopes to decay before you can use the pad again..

 

[Guest]

6 minutes ago, GregroxMun said:

Is that an open cycle Gas Core NTR? Because if so, wow. We need a mod that makes Kerbalkind *hate* you (reputation drop) if you use this in the atmosphere. Open cycle gas core NTRs are notorious for spewing hot radioactive death out of their nozzles. By comparison, the Closed Cycle "Nuclear Lightbulb" NTR is far less deadly, and will only release hot radioactive death if it explodes or something, which is probably true of most NTRs. Downside is of course lower Isp and TWR.

I'm on it. 

[White Owl]

It's a glorious and exciting day for Nertea fans everywhere! 

[smjjames]

45 minutes ago, billkerbinsky said:

Also should include StageRecovery-like hook that penalizes you if anything nuclear-powered crashes and/or burns on the surface of Kerbin.   Besides reputation, I'd expect it to immediately cost cash (for cleanup & decontamination), as well as increased part cost..    And if you drop it in or around KSC, you might have to wait for any short-lived isotopes to decay before you can use the pad again..

 

Isn't the NERV open cycle?

[billkerbinsky]

32 minutes ago, smjjames said:

Isn't the NERV open cycle?

No, the propellant never comes in direct contact with the solid nuclear fuel.

See also https://en.wikipedia.org/wiki/Gas_core_reactor_rocket#Open_cycle_versus_closed_cycle

[Proteus]

 nukes were always my main horse work in ksp,thank you sir for those engines!

the more nukes the better!

[DDE]

Any plans for a competing close-cycle GCNTR?

Also, if open-cycle GCNTR, then why not NSWR, for the lulz?

A more on-point question: how does it mix with the LH2 chemicals mod? Is that mod getting refrigeration costs too?

I'm not rushing to download because I'm sticking with Porkjet's mod and don't want to mess with my own Firespitter converters.

[smjjames]

2 hours ago, DDE said:

Any plans for a competing close-cycle GCNTR?

Also, if open-cycle GCNTR, then why not NSWR, for the lulz?

A more on-point question: how does it mix with the LH2 chemicals mod? Is that mod getting refrigeration costs too?

I'm not rushing to download because I'm sticking with Porkjet's mod and don't want to mess with my own Firespitter converters.

If you're worried about InterstellarFuelSwitch messing with Firespitter, I have both and they don't interfere with each other.

[Whirligig Girl]

I've taken a look at the stats for Open Cycle Gas Core NTR, and it's only about 125 seconds of specific impulse more efficient than the Closed Cycle Gas Core "Nuclear Lightbulb" NTR from Porkjet.

 

I've taken a look at atomic engine stats. Closed cycle gas core has an I_sp of 2,000 seconds. Open cycle gas core (which is the model of the gas core there) has an I_sp of 3,000 seconds, and a whole lot more thrust. This Open Cycle Gas Core rocket is borderline Torchdrive levels of thrust and Isp. Accounting for a nerf for Kerbal Space Program (where Porkjet's lightbulb has an Isp of 1500 seconds, and the Kerbal Atomics open-gas-core has an Isp of 1625), we take the lightbulb as the basis for finding the Isp of the open gas core, and assume the same ratio of Isp as the realistic version from Atomic Rockets we get a specific impulse for the Open Cycle Gas Core NTR of 2250 seconds.

So what I'm, proposing is that you make the specific impulse 2250 seconds, and then figure out how to nerf it. Make its atmosphere Isp even more pitful so no one ever thinks it's a good idea to use it in Kerbin's atmosphere, or something.

 

Of course, it's your mod, so do whatever you want.

[aristurtle]

Awesome, I've been looking forward to this!

[speedwaystar]

what are your plans regarding Near Future Technologies and the division into Electrical, Propulsion etc? i guess you've decided to further subdivide Propulsion into Nuclear, Cryo and so forth?

[Whirligig Girl]

21 minutes ago, speedwaystar said:

what are your plans regarding Near Future Technologies and the division into Electrical, Propulsion etc? i guess you've decided to further subdivide Propulsion into Nuclear, Cryo and so forth?

Cryo isn't near future. It's modern and historical.

[Bluebottle]

That's some beautiful modeling and texture work, right there. Installing, alongside all your other mods!

[Mackilroy]

Thumbs up for another great mod! Thanks so much.

[Nertea]

Glad you all enjoy it. It was a lot of fun making these models (sometimes), the challenge of laying out the plumbing was quite interesting. 

16 hours ago, GregroxMun said:

Is that an open cycle Gas Core NTR? Because if so, wow. We need a mod that makes Kerbalkind *hate* you (reputation drop) if you use this in the atmosphere. Open cycle gas core NTRs are notorious for spewing hot radioactive death out of their nozzles. By comparison, the Closed Cycle "Nuclear Lightbulb" NTR is far less deadly, and will only release hot radioactive death if it explodes or something, which is probably true of most NTRs. Downside is of course lower Isp and TWR.

It's closed cycle (they don't all have to look like that NASA study). As you point out, the stats are not nearly good enough for an open cycle. I do want to do an open cycle one at some point, but I haven't decided on the exact shape or form factor.

8 hours ago, DDE said:

Any plans for a competing close-cycle GCNTR?

Also, if open-cycle GCNTR, then why not NSWR, for the lulz?

A more on-point question: how does it mix with the LH2 chemicals mod? Is that mod getting refrigeration costs too?

I'm not rushing to download because I'm sticking with Porkjet's mod and don't want to mess with my own Firespitter converters.

NSWR is in the works and would probably arrive with the OC GCNTR, I'll probably make it the mod's only 3.75m engine when I do. I haven't settled on a style/visualization yet, but it looks like most of the detail will be in the cooling systems for the nozzle

Generally, this mod should mesh perfectly with CryoEngines (if that's what you mean by LH2 chemicals) in balance and function. 

[smjjames]

I can't seem fo find the boiloff thing (or I don't know where to look) edit: Found the boiloff module itself and deleted it. and I'm unsure on the configs:

KerbalatomicsNFE: Does this turn the engines into reactors? I'm confused.

kerbalatomicsenginelight: Is it okay if this is removed? No idea what it's for.

various NTR conversions from LF to LH2: Are the nuke engines generally more efficient with LH2? Would also be nice (if possible) for a switch between LF and LH2 modes. Nvm, they aren't, at least the lightbulb engine isn't, or doesn't seem to be and needs more fuel for the deltaV which it gets with LF.

Edited January 23, 2016 by smjjames

[Whirligig Girl]

2 hours ago, Nertea said:

It's closed cycle (they don't all have to look like that NASA study).

I haven't see any design anywhere for a closed cycle gas core thermal rocket that doesn't look like that NASA study. There's a reason why they made it look like that, after all. They didn't just do it because it looked cool. Besides, i really like that NASA study. You could repurpose the Liberator's model as the open cycle design and then make a closed cycle model that looks like the NASA study. It would then fit much better with NearFuture, Ven's Stock Revamp, and the rest of Kerbal Atomics than Atomic Age does.

 

EDIT: I have found a design for a closed cycle gas core NTR that doesn't look like the NASA study.

Edited January 23, 2016 by GregroxMun

[billkerbinsky]

Large zero-boiloff LH2 tanks take significant power for cooling - at the extreme end, the HI-530 takes 115.20 Ec/s.     Stock launch clamps provide 1 Ec/s each.   (The SpaceY large launch clamps provide 2 Ec/s each).   Seems like there's an unfilled niche for a higher-power bit of ground-support equipment to keep cryo tanks powered and topped off.   (Just for fun, It should probably emit a vent plume like you see for most liquid-fueled launches..)