[1.12.x] Cryogenic Engines: Liquid Hydrogen and Methane Rockets! (August 13, 2024)

[Nertea]

Repo is up and functional, pull request away. I fixed a few things in the meantime.

I'm going to start working on clusterable no-ring versions of the engines. I'm not sure what to do with the gimbal hydraulics though. Generally the pistons extend out to the edge of the ring except for in a few cases. To make a good looking clusterable engine I'll need to address this in one of 3 ways:

1. Do nothing, the upper piston mounts floating at the deleted ring's edge is ok
   
2. Move the upper piston mounts inwards as much as possible without breaking the connections to minimize the radius of the top of the engine
   
3. Remove the pistons entirely
   

What's the best option?

Would you consider making a plugin for the Rapier (and the Broadsword from your own Mk4 mod) to use LH2/LOX instead of LF/LOX during closed cycle alongside an increased ISP of 460 (or a bit less if you want to balance it with the regular cryogenics)? Open cycle would still use LF.

You can do that yourself with MM pretty easily .

[mikegarrison]

Repo is up and functional, pull request away. I fixed a few things in the meantime.

I'm going to start working on clusterable no-ring versions of the engines. I'm not sure what to do with the gimbal hydraulics though. Generally the pistons extend out to the edge of the ring except for in a few cases. To make a good looking clusterable engine I'll need to address this in one of 3 ways:

1. Do nothing, the upper piston mounts floating at the deleted ring's edge is ok
   
2. Move the upper piston mounts inwards as much as possible without breaking the connections to minimize the radius of the top of the engine
   
3. Remove the pistons entirely
   

What's the best option?

Maybe cluster engines shouldn't gimbal?

[Darth Lazarus]

Maybe cluster engines shouldn't gimbal?

i would say that this sould depend on the engines, complexity etc.

maybe adding small vernier engines for steering?

[Nertea]

It's not going to be a cluster, it's just going to be a version of the engine model that lacks the ring assembly at the top so it is more size-versatile. There's no reason it shouldn't gimbal at all (and it fact, removing ALL the gimbal hardware would be a bunch of work).

[NathanKell]

If 2's not prohibitively time-consuming, that seems the best option to me. In general you'd want the pistons going up to an (invisible) ring no wider than the nozzle diameter, that should work. Otherwise, I'd guess 3, since in most cases the existing rings are rather too wide to be workable...

Thanks for the repo (and for doing this extra work, and for the mod itself, and...)

[Nertea]

No problem!

This is about what I'll be doing. The RL-10 needed few changes as the gimbal assembly was already really tiny. Seems good?

[blowfish]

I'm going to start working on clusterable no-ring versions of the engines. I'm not sure what to do with the gimbal hydraulics though. Generally the pistons extend out to the edge of the ring except for in a few cases. To make a good looking clusterable engine I'll need to address this in one of 3 ways:

1. Do nothing, the upper piston mounts floating at the deleted ring's edge is ok
   
2. Move the upper piston mounts inwards as much as possible without breaking the connections to minimize the radius of the top of the engine
   
3. Remove the pistons entirely
   

What's the best option?

Very excited for this I guess the Ct10 and KS-68 are the easy cases because you can just delete the outer ring. The relevant bits might have to have their AO rebaked (or just removed) though - I recall there being a bit of empty space in the texture, so if it's not too much trouble those particular pieces of texture could be duplicated to the empty space. For the Ct65 I think you could just move the struts to the inner ring. The rest are less certain I guess - keep the pistons if possible, but I guess it's still worth asking whether the ring should be removed or just shrunken.

BTW, I don't think it's necessary to make the attachment base as small as possible. If they're the same size as the nozzle, or only slightly bigger, that's probably fine as far as clustering is concerned

EDIT: Ninja'd ... I guess you're going with removing the rings then?

[Nertea]

Yes, I'm removing the rings as far as I can. It's a bit of a pain, not only am I having to rebake AO, but in some cases I have to add polys and texture to areas that were previously invisible. Luckily, as you point out, there's some space in the texture for a few extra bits. There are also going to be duplicate piston sets in the model for the ringed and bare versions. It looks like it's going well though, the realigned Vulcain is working out alright.

Unfortunately that's about all I'll be able to do tonight. Will resume at next free time index.

Edited September 17, 2015 by Nertea

[More Boosters]

You can do that yourself with MM pretty easily .

Alright I will look into it to do it for myself; I suggested it mainly for your add-on at Near Future to convert nukes to use LH2; that's the case for the RAPIER too (in both cycles apparently)

[Darth Lazarus]

Nertea ... perfect ... can i marry you know?

i always wanted engines, where the attachmentpoint has teh same diameter as the nozzle and not the huge ring/baseplate/tankbottom ... better for clusters.

maybe you can add a tweakconfig , where teh ring/baseplate can be shown like in teh stock reamp mod? so we can build tght clusters or use a single engine as normal with a pretty attachment.

[davidy12]

Finally! Getting rid of those ugly rings, I can finally make proper engine clusters. Thanks so much!

[NathanKell]

Nertea, awesome!

If anything I'd suggest extending the piston upper bits to rather above the node, so that one can place the engine on a dome, or place 2x around a dome, and not have the arms hanging in the aether. Text example:

| | |
 \o/
 | |
/   \

where the o is the attach node, and above it run the piston mounting arms and the fuel/ox pipes.

The tough part of course is making sure even the extended bits don't go outside the nozzle diameter....

[Nertea]

Maybe I'll save that for a future update, because I finished this just now and want to proceed forwards .

I'll update the OP album with renders of the frame-less engines at some point, not sure when though.

0.1.10

• Updated ISFuelSwitch plugin to 1.16
  
• Updated to latest CRP version (0.4.4)
  
• Updated ModuleManager version (2.6.6)
  
• Bundled Mini-AVC for versioning
  
• Fixed a capitalization error in CryoEnginesLFO patch
  
• Fixed MFT patch to be mutually exclusive with RealFuels
  
• Added new versions of all engines that lack the support ring around the top. Toggle in the editor.
  
• Added new optional patch: CryoEnginesSurfaceAttach, which allows all engines to be surface attached
  

Finally! Getting rid of those ugly rings, I can finally make proper engine clusters. Thanks so much!

*sadface* I worked hard on those rings .

Edited September 18, 2015 by Nertea

[Darth Lazarus]

... Nertea, you are just in time. thank you very much for your fast work

and my NASA upperstages look way better with the right engine

DCSS with ring and ACES without rings

[davidy12]

*sadface* I worked hard on those rings .

I didn't mean it like that, I just think its good we can make better engine clusters.

[More Boosters]

I like the rings can we keep them as an option?

[Darth Lazarus]

I like the rings can we keep them as an option?

read carefully, rings/no rings is toggable now

[Randazzo]

Finally! Getting rid of those ugly rings, I can finally make proper engine clusters. Thanks so much!

I like the rings can we keep them as an option?

The joy of modding.

These look incredible, nice work as always.

[Nertea]

... Nertea, you are just in time. thank you very much for your fast work

and my NASA upperstages look way better with the right engine

DCSS with ring and ACES without rings

http://i.imgur.com/PglhDAT.jpg

http://i.imgur.com/VLN1wAq.jpg

Very nice.

I didn't mean it like that, I just think its good we can make better engine clusters.

I was just kidding

I like the rings can we keep them as an option?

:|

Added new versions of all engines that lack the support ring around the top. Toggle in the editor.

[davidy12]

I knew that. XD *I MEAN IT*

[xebx]

Real LH2/LOx engines (Ariane 5 Vulcain, Delta IV RS-68) runs with mixture ratio 1:6 (and tanks volume ratio is 1:5), why Cryogenic Engines Mod runs with 1:10 ? Is it possible to fix this ? (or am i reading a wrong ratio ?)

I've been using this mod in RSS with lots of tweaks (mostly thrust, weight, and procedural tank dry weight, full weight and volume to match official data), and after a few tries i ended with the same ascent trajectory (slightly falling for the last 15-20%) to orbit Earth with Ariane 5 launcher, that was very interesting.

In my opinion, Hydrolox engines needs to be stock and are clearly indispensable for RSS.

Thanks for this mod !

Edited September 19, 2015 by xebx

[More Boosters]

Real LH2/LOx engines (Ariane 5 Vulcain, Delta IV RS-68) runs with mixture ratio 1:6 (and tanks volume ratio is 1:5), why Cryogenic Engines Mod runs with 1:10 ? Is it possible to fix this ? (or am i reading a wrong ratio ?)

I've been using this mod in RSS with lots of tweaks (mostly thrust, weight, and procedural tank dry weight, full weight and volume to match official data), and after a few tries i ended with the same ascent trajectory (slightly falling for the last 15-20%) to orbit Earth with Ariane 5 launcher, that was very interesting.

In my opinion, Hydrolox engines needs to be stock and are clearly indispensable for RSS.

Thanks for this mod !

It is possible to fix this. Go to the CryoEngines folder at GameData, go to parts and pick the .cfg of the one you want. There you can set ISP, Thrust and mass ratio for an engine and the game calculates how much fuel is expended per second.

[JPmAn]

Where can I get the Surface-Attach?

[billkerbinsky]

Real LH2/LOx engines (Ariane 5 Vulcain, Delta IV RS-68) runs with mixture ratio 1:6 (and tanks volume ratio is 1:5), why Cryogenic Engines Mod runs with 1:10 ? Is it possible to fix this ? (or am i reading a wrong ratio ?)

so that's a unit:unit mixture ratio, not a volume mixture ratio. 1 unit of stock Oxidizer occupies more tank space than 1 unit of LqdHydrogen. Look at how many units of Oxidizer and LqdHydrogen a tank holds when it's only holding one resource.

If you want to look under the covers, look over CryoEngines/Patches/CryoEnginesFuelTankSwitcher.cfg, and look over this thread and the Community Resource Pack thread.

The community resource pack settled on a standard volume of 1 unit = 1 liter, vs the ~5 liter/unit volume of stock fuel and oxidizer, but then the LH density was fudged upwards by 50% to compensate for the higher mass fractions dry weight in KSP vs reality.

Edited September 21, 2015 by billkerbinsky
got something backwards

[More Boosters]

so that's a unit:unit mixture ratio, not a volume mixture ratio. 1 unit of stock Oxidizer occupies more tank space than 1 unit of LqdHydrogen. Look at how many units of Oxidizer and LqdHydrogen a tank holds when it's only holding one resource.

If you want to look under the covers, look over CryoEngines/Patches/CryoEnginesFuelTankSwitcher.cfg, and look over this thread and the Community Resource Pack thread.

The community resource pack settled on a standard volume of 1 unit = 1 liter, vs the ~5 liter/unit volume of stock fuel and oxidizer, but then the LH density was fudged upwards by 50% to compensate for the higher mass fractions in KSP vs reality.

I don't get this. In KSP these cryogenic engines are very rarely more efficient than LF/LOX engines, usually only good for upper stages (ironic as cryogenics are mostly used at lower stages in real life) and that's because it keeps the upper stages lighter.

Am I missing something? Because if what you say is true and these cryos are more effective than in real life, then how come cryogenic engines are considered better if more expensive?