[1.12] Explodium Breathing Engines v1.8.0: "Jet" engines for use on Eve and Jool [10 OCT 2021]

[Gordon Fecyk]

Time to tune the engines based on higher atmospheric pressures. I'm not sure what sure what direction to take them, though.

Playing with NASA's EngineSimU, I learned that higher pressures mean more mass to pull the engine through. Not changing anything else, this means a lot more thrust if one can sustain the fuel (or oxidizer in my case) flow, and the engine doesn't overheat. On Eve though, the thicker air means more lift and not needing as much thrust. I might want to simulate an engine governor that actually reduces thrust in higher pressures.

This is a realism / gameplay balance problem now. I can certainly do more thrust based on the EngineSim numbers, and have engines fall off or melt without careful throttling. Or I can 'design in' a throttle governor by reducing the thrust. I could even adjust both atmCurve and atmosphereCurve and have specific impulse change with pressure, simulating the requirement of a higher chamber pressure, much like OhioBob's engines provide more thrust at higher pressures with lower specific impulse. I could also leave them alone; they seem to work fine as-is from a gameplay view.

[Gordon Fecyk]

Thicker Air Means More Thrust

After playing with normal air breathing jets on Galileo's world Tellumo and its ten atmospheres' worth of air, I produced extensions to the stock jets' atmCurve float curves to allow for more thrust in more dense air. I did that with Advanced Jet Engines, that uses NASA's EngineSim code to calculate thrust. That's a whole other project.

Once the stock jets had reasonably extended atmCurves, I applied the same extended atmCurves to the Explodium versions here.

The result is that these engines now have more thrust the lower you go in Eve's thick atmosphere. The Zephyrus gets the most benefit up to three to four atmospheres, but seems quite prone now to overheating; watch that throttle carefully. The Hades actually becomes useful in smaller planes, as long as you watch out for excessive dynamic pressures. And the rest have benefits and drawbacks of their own to discover.

It's late for me now so I haven't published a release 1.1, but the updated configurations are in the repository. You can copy the updated Engine folder into your game to see the changes.

[Gordon Fecyk]

Version 1.1.0 now available from SpaceDock and GitHub. This release includes the extensions to the atmCurve float curves derived from experimenting with Advanced Jet Engines on Tellumo, a 'super-Kerbin' world in Galileo's Planet Pack. The results of that experiment are in the Jet Engine Curve Extender project.

[Gordon Fecyk]

Looks like this works on v1.4.1 without changes. Make sure you use a current Module Manager version for KSP 1.4.1 compatibility. 

[Gordon Fecyk]

I did it!

Not by much, and with a few asterisks, but I did it...!

https://kerbalx.com/gordonf/Big-OX

This version couldn't make it back down, but a version with a cluster of radiators did.

[MrFancyPL]

Hello, can you add compatibility to the KER or other mod that shows DeltaV ?

[JadeOfMaar]

2 hours ago, MrFancyPL said:

Hello, can you add compatibility to the KER or other mod that shows DeltaV ?

You don't write compatibility configs for KER. Everything simply works. The part where you'll get dV problems is where this mod, I think, does not provide tanks for ExplodiumVapor. So you only ever have the total amount that the intakes are holding so dV calculations will always be short.

However, what I think (but am not absolutely sure of) @Gordon Fecyk may need to do is ensure that for all his engines, the PROPELLANT[ExpVapor] nodes contain this key ignoreForIsp = True so KER will use only Oxidizer to calculate dV for the engines.

[Gordon Fecyk]

2 hours ago, JadeOfMaar said:

However, what I think (but am not absolutely sure of) [that I] may need to do is ensure that for all his engines, the PROPELLANT[ExpVapor] nodes contain this key ignoreForIsp = True so KER will use only Oxidizer to calculate dV for the engines.

I was wondering about this.

This is what the J-34 Zephyrus propellant sections look like after Module Manager has its way with it:

			PROPELLANT
			{
				name = ExpVapour
				ignoreForIsp = True
				ratio = 0.366
				DrawGauge = False
			}
			PROPELLANT
			{
				name = Oxidizer
				resourceFlowMode = STAGE_STACK_FLOW_BALANCE
				ratio = 1
				DrawGauge = True
			}

This is similar to the IntakeAir setting since I'm just editing PROPELLANT[IntakeAir] to make the ExpVapour entry. Would I need to explicitly include ignoreForIsp = False for Oxidizer? 

[Post-testing] After explicitly including ignoreForIsp = False for Oxidizer on the J-X5 Beelzebub engine, I'm not seeing any difference in per-stage delta-v values for the Big-OX craft in Kerbal Engineer. It still displays miniscule values, like 16 m/s. KSP itself displays what looks like a valid specific impulse value in the engine's info window; it should be 1810 seconds due to the ExV / OX reaction being weaker than IA / LF.

I wonder if Kerbal Engineer is ignoring OX always and just focusing on what the other propellant is. Those intakes / harvesters only store a little a bit of ExV.

Edited May 7, 2018 by Gordon Fecyk
Testing results

[JadeOfMaar]

3 minutes ago, Gordon Fecyk said:

This is similar to the IntakeAir setting since I'm just editing PROPELLANT[IntakeAir] to make the ExpVapour entry. Would I need to explicitly include ignoreForIsp = False for Oxidizer? 

I'm hoping this is the case already, since you merely change the resource name there. The snippet from MM is how it should be. But no, don't apply it to Oxidizer. That should actually make things worse.  

If you build a plane right now with the J-34 Zephyrus and a bix Oxidizer tank, will KER give you reasonably high numbers (like a few thousand m/s)?

[Gordon Fecyk]

10 minutes ago, JadeOfMaar said:

If you build a plane right now with the J-34 Zephyrus and a bix Oxidizer tank, will KER give you reasonably high numbers (like a few thousand m/s)?

No. In fact I built a Kerbal-X-alike using J-34s as a first stage booster, and delta-v for that stage stays fixed at 17 m/s. 

[Gordon Fecyk]

Two Major Changes Need Testing Were Published

The current repository, but not a release (v1.2.0 now released), has Ferram Aerospace Research adjustments to change the aerodynamic properties for intakes / harvesters and wet wings. This seems to correct a FAR incompatibility problem where the centre of lift arrow would appear when it shouldn't.

Also, the current edition of Kerbal Engineer Redux, maintained by @jrbudda, now displays sane delta-v values for the engines.

I can confirm basic compatibility with KER 1.1.5.2 and an unofficial FAR v0.15.9.2 for KSP 1.4.3. I can also confirm basic compatibility with the official FAR release v0.19.5.1 for KSP 1.3.1. And that I'm going to need to re-design my SSTEO space planes.

Edited June 20, 2018 by Gordon Fecyk
Changes now released in v1.2.0

[Gordon Fecyk]

Major Overhaul of Part Configs

Because of trouble I ran into with Kerbal X, I converted all part configurations to complete parts and not just Module Manager-generated clones.

If anyone has time, please download a copy of the current repository and see if anything breaks. I'll do a new release after I've added comments back to the part configs.

[Gordon Fecyk]

Release 1.3.0 Available

General Release 1.3.0 now available from GitHub and SpaceDock. This release should fix craft uploads to Kerbal X, and I'll make the parts available to Kerbal X shortly. Also I fixed some localization to avoid confusing opening and closing the harvesters with starting and stopping them.

[Zosma Procyon]

Wouldn't nuclear thermal turbine engines be simpler?

[DStaal]

2 minutes ago, Zosma Procyon said:

Wouldn't nuclear thermal turbine engines be simpler?

Nukes are heavy, dangerous to work around, and it's hard to refine their fuel.  (Luckily they don't need much of it.)  There's arguments to be made both ways - and there are other mod packs with nuclear jet engines, so you can try both out in your game.

[Zosma Procyon]

4 minutes ago, DStaal said:

Nukes are heavy, dangerous to work around, and it's hard to refine their fuel.  (Luckily they don't need much of it.)  There's arguments to be made both ways - and there are other mod packs with nuclear jet engines, so you can try both out in your game.

We're talking about a video game universe populated by little minions that get their nutrients through photosynthesis and have no self preservation instinct. I think it would be easier to program a nuclear jet engine that will simply breath whatever air is present around it.

[DStaal]

17 minutes ago, Zosma Procyon said:

We're talking about a video game universe populated by little minions that get their nutrients through photosynthesis and have no self preservation instinct. I think it would be easier to program a nuclear jet engine that will simply breath whatever air is present around it.

And there are several other mods which have already done that.  There's one in the Near Future mods I know off the top of my head.

[Zosma Procyon]

5 hours ago, DStaal said:

And there are several other mods which have already done that.  There's one in the Near Future mods I know off the top of my head.

Near future requires too many dependencies for my system.

[DStaal]

9 hours ago, Zosma Procyon said:

Near future requires too many dependencies for my system.

I'd argue, but that pack does contain four dependencies.  Still, it was just one example and doesn't impact my main point: Complaining in this mod's thread doesn't get you anything.  You aren't being forced to use it, and there *are* mods that do what you want.

You don't like this mod?  Fine.  Ignore it.

[Zosma Procyon]

4 hours ago, DStaal said:

I'd argue, but that pack does contain four dependencies.  Still, it was just one example and doesn't impact my main point: Complaining in this mod's thread doesn't get you anything.  You aren't being forced to use it, and there *are* mods that do what you want.

You don't like this mod?  Fine.  Ignore it.

It's more a problem with my Macbook Pro. I can't get the game to consistently run fast on it. And I can't get 1.5.1 to work at all, but that's another ongoing saga.

Edited November 7, 2018 by Zosma Procyon

[DStaal]

43 minutes ago, Zosma Procyon said:

It's more a problem with my Macbook Pro. I can't get the game to consistently run fast on it. And I can't get 1.5.1 to work at all, but that's another ongoing saga.

Drop the IVAs, you'll save a lot of RAM.  Other than that - I've run KSP fairly well on a gen-1 Mac Pro, with over a hundred mods.  Some mods slow things down more than others, and having more ships/debris in flight will slow things down.  Near Future - or this mod - have very little effect if you're already swapping RAM.

[Gordon Fecyk]

On ‎11‎/‎6‎/‎2018 at 4:47 PM, Zosma Procyon said:

Wouldn't nuclear thermal turbine engines be simpler?

The engines that just suck in atmosphere and squirt it out the back?  You're looking for Atomic Age. And that has two dependencies.

This one's a stock-alike take on jet engines and it doesn't even depend on Module Manager anymore. I've worked out all of the technical bits, though I might have to inspect the 1.5.1 stock jets for changes to their float curves and make sure I'm using similar curves here for a 1.5.1 release of this. But Explodium Breathing Engines otherwise works in KSP 1.5.1 without changes, being just a part mod and no software.

[Gordon Fecyk]

1.4.0 Release for KSP 1.7

I released updates to Explodium Breathing Engines to accommodate KSP 1.7, and to fix Module Manager warnings when using RealPlume Stock. There are also resource adjustments.

If you want the updated RealPlume configs now, you can copy the configs from my fork. 

[Meid]

Can i make a config for my kopernicus planet pack that allows the usage of the intakes on that planet?

[Gordon Fecyk]

On 9/16/2019 at 1:06 PM, "Our Benefactors" said:

Can i make a config for my kopernicus planet pack that allows the usage of the intakes on that planet?

Sure, and you (or I) could add it to the next release. What's the name of the world? You need only edit ExplodiumVapour.cfg in Resources to add your planet to the list.

And for everyone else: RealPlume Stock now contains native support for Explodium Breathing Engines. They added the ethane plume to RealPlume and the plume configurations to RP-Stock.