[1.x+] Community Resource Pack

[RoverDude]

NorthStar. I've asked like... five times now to please take this to another thread (i.e. the RealFuels one) or take it to PM.

Keep it up and I will ask for moderation.

[Northstar1989]

NorthStar - with all due respect, we need to let this bit go.

You are correct my dear sir.

Could we just fix the density of Ammonia (a resource that gets much more use in KSP-Interstellar than in RealFuels- in the latter it has an inferior density/ISP combination than Methane and gives less Delta-V for most NERVA+spacecraft configurations than Methane anyways...) so that it's 702.1 kg/m³ before we do so? I think I've made some rather compelling arguments about why it makes more sense to store it at -50 C than at -40 or -34 C...

We're past discussing densities for now, and focusing on getting the first cut taken care of. At that point, if there are any issues - and within that context, only between shared resources, and between two mods with a conflict, we'll bring it up.

All the other densities look good- so the only one I'm still currently worried about is Ammonia. Which is used by both RealFuels and KSP-Interstellar, although it gets much more use in the latter.

An interesting note on the use of Ammonia in RealFuels, by the way. FreeThinker pointed me to some rather interesting Thrust/ISP tables for Nuclear Thermal Rockets a while back from the Atomic Rockets website... Apparently the Thrust you're using in RealFuels for Ammonia is much too low, as at the temperatures of a Nuclear Thermal Rocket your Ammonia propellant breaks down into Nitrogen and Hydrogen gas (so the number of gas molecules doubles) in the exhaust stream- significantly increasing your Thrust at no additional mass or heat requirement on your rocket's part... I'll have to get those tables/calculations to you at some point in the future.

Just need us to stay on task as time is limited, and we all have a lot of work to do.

Indeed. You're right we shouldn't quibble too long over stuff like densities when 1.0 is getting so close...

What is holding you back from adjusting the density of Ammonia to its density at a lower storage-temperature like we already do with Methane and Oxygen (even if I haven't managed to convince you yet that the density of LOX of 1142 kg/m³ does indeed come from chilling it further than its boiling-point along...) What sources, data, or support could I provide you with so I could quickly convince you of my point, and we can move on to more important stuff? Or are you absolutely not going to budge on this, and insist that I abandon this rather important discussion (considering Ammonia's value in KSP-Interstellar) for later?

Also, what other things do we still need to look at or fix? Costs, I take it? Are we all good with naming, or are there any lingering issues there I'm not aware of?

Regards,

Northstar

[RoverDude]

NorthStar.

First. You are talking about a difference per unit of 0.000098. Again... rounding territory.

Second. It's a KSPI-E resource... so I have no idea why you are even lobbying for a change in this thread... talk to FreeThinker.

Enough.

[Northstar1989]

I just wanted to summarize all the progress we've made so far on some resources used by KSP-Interstellar (or that will be in the near future according to FreeThinker- who wants to finalize the transition over to CRP densities for Hydrogen and Oxygen in the future if I understood him correctly...), just so it's clear I'm not trying to be difficult...

Resources with good densities:

LqdHydrogen (close enough for government work!)

LqdOxygen (my point was that the value does *not* need adjusting- it is based off a super-cooled temperature below the boiling-point, as it should be)

LqdMethane

LqdCO2

LqdNitrogen

Resources still in need of densirty-adjustment:

LqdAmmonia (currently 604 kg/m³, should be 702.1 kg/m³- the density at -50 C)

I'll try to compile a similar lists for costs (which I haven't spotted any issues with yet- but I'll want to double-check). And expand this list to include other resources as I check them more carefully.

Regards,

Northstar

- - - Updated - - -

Second. It's a KSPI-E resource... so I have no idea why you are even lobbying for a change in this thread... talk to FreeThinker.

Wait, so FreeThinker has permission to change the density for Ammonia to 702.1 kg/m³ if he's OK with this?

Sweet! I think he will be fine with this change...

Regards,

Northstar

Edited March 15, 2015 by Northstar1989

[RoverDude]

Hell, FreeThinker has full write access to that portion of the document. I'm just waiting for everyone to flag things as done.

RE costs, etc. - bring those up with the relevant curator, not in this thread please.

In case folks kinda forgot what this is for - this is about making sure we do not stomp over eachother. But at the end of the day, I trust the individual curators to do the right thing (i.e. I don't quibble with Taranis over definitions for Oxygen, or Universal Storage for their Hydrogen definition).

The only time we should be bringing stuff up in this thread is if there's a significant issue or game-breaking proposal - like unification of a nuclear fuel, establishing Lqd as our prefix, 1L units, etc.

The detail stuff (costs, specific densities, etc.) stick with whoever is curating the mod that owns it unless it's causing some kind of breaking issue.

[Northstar1989]

Hell, FreeThinker has full write access to that portion of the document. I'm just waiting for everyone to flag things as done.

RE costs, etc. - bring those up with the relevant curator, not in this thread please.

In case folks kinda forgot what this is for - this is about making sure we do not stomp over eachother. But at the end of the day, I trust the individual curators to do the right thing (i.e. I don't quibble with Taranis over definitions for Oxygen, or Universal Storage for their Hydrogen definition).

The only time we should be bringing stuff up in this thread is if there's a significant issue or game-breaking proposal - like unification of a nuclear fuel, establishing Lqd as our prefix, 1L units, etc.

The detail stuff (costs, specific densities, etc.) stick with whoever is curating the mod that owns it unless it's causing some kind of breaking issue.

Alright, well the problem then is that LqdAmmonia is a resource shared by both RealFuels and KSP-Interstellar Extended. The density absolutely needs to be adjusted, though: the density is currently 604 kg/m³ in the document- the density of Ammonia even at its boiling-point (-34 C) is 682.778 kg/m³...

The density I want to go with (I help develop KSP-I Extended, in the same way Regex helps develop RealFuels) is the density at -50 C: 702.1 kg/m³, but the density Regex seems to be favoring is either 682.778 kg/m³ (density at -34 C, the boiling-point: but many other cryogenic densities are already based off lower temperatures than boiling-point, LOX for instance) or 690.2 kg/m³ (density at -40 C, which is ambient temperature of Low Earth/Kerbin Orbit in RealFuels- but ambient is -80 or lower in interplanetary space or out by, say, Jool- which is why I want to go with density at -50 C, as it is the lowest temeprature I can get reliable density-data for...)

The issue boils down to what to change the density of LqdAmmonia to, not whether to change it. All parties involved can agree that the current density of 604 kg/m³ is too low- as this is less than the density of Ammonia at 1 atm and its boiling-point...

So, what I'm not clear on is this: can FreeThinker play the ultimate judge on this issue since he has Full Edit permissions on LqdAmmonia (and it is listed as a primarily KSP-I resource in the CRP working-document), or do we need to all come to some sort of consensus on the issue first?

Regards,

Northstar

Edited March 15, 2015 by Northstar1989

[regex]

Alright, well the problem then is that LqdAmmonia is a resource shared by both RealFuels and KSP-Interstellar Extended. The density absolutely needs to be adjusted, though: the density is currently 604 kg/m³ in the document- the density of Ammonia even at its boiling-point (-34 C) is 682.778 kg/m³...

I'm going to cut this off right now. Liquid Ammonia is a KSPI resource and is curated by KSPI, even if Real Fuels uses it for some off-brand nuclear engine configs. Therefore, do what you need to do.

Real Fuels itself will strive for consistency and easy, real world reference (considering that KSP does not concern itself with elastic densities) rather than some arbitrary densities that someone thought "sounded reasonable" and are open to endless debate about. Therefore, any resource under Real Fuels curation will assume STP density for non-cryogenic resources and liquid phase density at boiling point if it is a cryogenic resource (which is incidentally the 1142kg/m³ value that you see for LOX). If you have an issue with this, bring it to the Real Fuels thread.

[RoverDude]

Just have FreeThinker change it. I keep saying this.

Just as RegEx has free reign to change anything he wants in RealFuels.

If there are debates with the decisions, sort them out via PM or in the RealFuels thread.

[Northstar1989]

Just have FreeThinker change it. I keep saying this.

Just as RegEx has free reign to change anything he wants in RealFuels.

If there are debates with the decisions, sort them out via PM or in the RealFuels thread.

Alright, will do. I'll make sure FreeThinker knows he has full permission to change the density.

Also, who's responsible for ratifying the LqdCO2 resource? It's used by KSP-Interstellar Extended (and no other mod that I know of, now that BioMass was removed from the process due to lack of communication), but is currently listed as a USI resource. Why is this?

As it stands, I see no issue with the density, cost, or any other parameters of LqdCO2- so I would very much like to see it ratified. If it was listed as a KSP-I resource, I could ask FreeThinker to confirm if he is good with it as it stands- but who is it that manages the USI resources, and why is LqdCO2 even listed as a USI resource in the first place? (does USI use LqdCO2? If so, this was something I wasn't aware of...)

Regards,

Northstar

[RoverDude]

Me. I'll set it as confirmed.

[Northstar1989]

Therefore, any resource under Real Fuels curation will assume STP density for non-cryogenic resources and liquid phase density at boiling point if it is a cryogenic resource (which is incidentally the 1142kg/m³ value that you see for LOX).

Not the density of LOX at its boiling-point. That's less than 200 kg/m³, as I pointed out before. 1142 kg/m³ is the density at the significantly lower temperatures and slightly higher pressures (the latter only important for phase-transition and the temperature at which you find the boiling-point), such as were used on the Shuttle External Fuel Tank and the Saturn V LOX tanks...

You may have been misled into thinking the temperature of the LOX used was at the boiling-point because 99% of sources of the Shuttle EFT and Saturn V LOX tanks use hand-waving statements like "The liquid oxygen tank functions as a huge vacuum bottle designed to store the cryogenic fluid at a very low temperature -- less than minus 297 degrees Fahrenheit" (this is from an article on NASA.gov).

This leads people to incorrectly thing the LOX was stored at -297 F (which is the boiling-point of LOX), when the key phrase here is actually "less than". The actual storage temperature on the pad must have been around -320 F, based on what we know of the LOX density in the Shuttle EFT. As the Shuttle ascended, this temperature could have been allowed to climb- as the LOX storage would not need to be as dense as the LOX tanks progressively emptied their mass into the engines- but it would always have to remain below -297 F in order to keep the LOX as a liquid: hence the phrase "less than minus 297 degrees Farenheit".

OK, well anyways, this is a dead-end discussion. So I'm going to drop it here... On to other topics...

Regards,

Northstar

- - - Updated - - -

OTHER TOPICS:

OK, so in real life (or at least on the Deep Space One and Dawn probes) the noble gasses used to propel ion engines (which have heretofore used Xenon due to its superior thrust and density- but could use lighter gases like Argon for better Exhaust Velocity and thus ISP if more electrical power was available, as with an onboard nuclear reactor...) are stored as supercritical fluids, not as gasses.

Here are the densities/temperatures/pressures of the different useful (helium is too expensive and difficult to store) noble gasses as superciritical fluids:

Neon: 481.91 kg/m³ - 26.79 atm, -228.66 C

Argon: 535.6 kg/m³ - 48.63 atm, -122.46 C

Krypton: 909.21 kg/m³ - 55.25 atm, -63.67 C

Xenon:: 1102.9 kg/m³ - 58.42 atm, 16.59 C

KSP-Interstellar Extended already has a NeonGas and KryptonGas entry on the CRP document, and I has suggested to FreeThinker we delete these and replace them with "SuperCrit Neon" and "Supercrit Krypton" instead. I also suggested KSP-I Extended add its own "SuperCrit Xenon" and "SuperCrit Argon" resources so as to not interfere with the existing "ArgonGas" and "XenonGas" resource definitions...

I mention this here because I was wondering if:

(1) NathanKell, Regex, etc. would be interested in adding supercritical noble gasses as resources with native RealFuels support. Basically, just add tanks definitions for these resources to RealFuels that rely on the definitions used in the CRP 2.0 release we are currently working on...

(2) Nerta would be interested in jumping on this bandwagon, and swapping NearFuture Propulsion to use a "SuperCrit Argon" resource instead of "ArgonGas" for its electric thrusters...

The benefits of using superciritcal noble gasses instead of their gas phases at STP should be quite obvious:

(1) You get much better mass-fractions than with gaseous storage. For instance, Argon is 300.9 times denser as a supercritical fluid (535.6 kg/m³) than as a gas at STP (1.78 kg/m³). Argon is only pressurized to 48.63 barr at its critical point, meaning you're going to require about 50 times the tank mass (the minimum tank-mass is directly proportional to internal pressure for a pressure-vessel in vacuum) for about 300 times the fuel mass. Which isn't a bad deal really- even if you chill ArgonGas to just above its boiling-point (-186 C) you're only going to increase fuel-density 3.24-fold (based on a density of 5.772 kg/m³ for Argon at -185 C). A better fuel tank mass-fraction means lower propellant-requirements for the same Delta-V or more Delta-V for the same fuel mass: which amounts to major cost-savings when you're sending a probe all the way to Eeloo...

(2) Your much higher fuel-density means your ion probe (or even nuclear-electric manned spacecraft!) has a much smaller aerodynamic profile. It's the difference between trying to lift a crumpled up ball of paper and a ball of lead through the atmosphere- and your Delta-V costs are going to be much, much lower (several hundred m/s lower if your launch vehicle only carries your probe to Low Orbit) to get the same mass of supercritical fluid to orbit considering the incredibly low density of the gas-phase... With the new drag-model in the stock aerodynamcis system coming out in 1.0, things like fuel-density will actually affect Delta-V costs to orbit without having to install FAR, and you will also be able to get away with a smaller probe inside cheaper+smaller fairings if you are using supercritical propellant on your interplanetary probe...

Regards,

Northstar

Edited March 15, 2015 by Northstar1989

[sal_vager]

Northstar1989, you've been asked to stop, so stop.

[RoverDude]

That talk can wait till after 1.0 as this boat has left.

Can we please eliminate the theorycraft? It is derailing the thread and the task at hand.

[Edit]

(Ninja'd by moderator - thanks!)

The appropriate place for that discussion is the KSPI thread. If FreeThinker chooses to change around how the stuff works and wants to discuss coordination with Nertea, then we can have that talk.

After 1.0.

[regex]

Okay, as long as ferram4 doesn't ask for any other weird solid fuels, the RF portion is finished for the next version.

[cantab]

Maybe this is a dumb question, but if things are going to be changed why not standardise on 1 unit = 1 kilogram? Then CRP doesn't have to worry about density at all, it's a matter for the people making storage parts to consider. And say Modmaker X reckons their tanks should hold Argon Gas at 150 bar and Modmaker Y reckons it should be 300 bar, both just give their respective parts the configs they reckon are right and neither is ignoring any density assumed by CRP.

[Crzyrndm]

Because then you have to get the cost right for your mod which:

A) makes the CRP pointless

KSP handles part costs in a really terrible way (dry cost = part cost - resource cost) so that has a lot of potential to end really badly if two mods conflict over it

[RoverDude]

Maybe this is a dumb question, but if things are going to be changed why not standardise on 1 unit = 1 kilogram? Then CRP doesn't have to worry about density at all, it's a matter for the people making storage parts to consider. And say Modmaker X reckons their tanks should hold Argon Gas at 150 bar and Modmaker Y reckons it should be 300 bar, both just give their respective parts the configs they reckon are right and neither is ignoring any density assumed by CRP.

Because this is not how resource definitions work. Density is kinda one of those required fields. Also you just kick the can down to everyone trying to figure out how large tanks should be, which becomes a balance nightmare. Oh... and how KSP handles cost and resources in general.

No thank you

[Northstar1989]

Northstar1989, you've been asked to stop, so stop.

Way ahead of you Sal

OK, well anyways, this is a dead-end discussion. So I'm going to drop it here... On to other topics...

I assume you meant the discussion of LOX-density, of course? (since that was what RoverDude wanted me to stop discussing)

The mention of adding supercritical-fluid noble gasses is something that I just brought up, and has never been discussed before (at least not recently) and is an entirely separate topic- one that I quite reasonably have the right to comment on in this thread, especially given that I help maintain/develop one of the mods participating in this effort (KSP-I Extended) and am trying to recruit other mod-authors to use these resources in their mods as well...

Of course, it was just a comment- not a discussion. There's no need to follow up on that unless Nertea or NathanKell/Regex bite on wanting to collaborate on these resources. Otherwise, adding supercritical noble gasses is just a private matter between myself and FreeThinker.

Regards,

Northstar

- - - Updated - - -

Okay, as long as ferram4 doesn't ask for any other weird solid fuels, the RF portion is finished for the next version.

Wait, FERRAM (the creator of the LEGENDARY Ferram Aerospace Research mod) asked for weird solid fuels? What did he want added, exactly?

Regards,

Northstar

Edited March 16, 2015 by Northstar1989

[RoverDude]

The KSPI thread is the appropriate place to discuss a proposed change to KSPI, not this one.

From my standpoint, the resource list is locked at this point until 1.0.

Afterwards, if a mod is preparing to release something new with some more bits, then it can be brought up for a point release.

[Northstar1989]

The KSPI thread is the appropriate place to discuss a proposed change to KSPI, not this one.

From my standpoint, the resource list is locked at this point until 1.0.

Afterwards, if a mod is preparing to release something new with some more bits, then it can be brought up for a point release.

Don't worry- there won't be any more discussion of those proposed resources, I already extended an invitation to Nertea and NathanKell/Regex/Starwaster to join in using those resources- which is the main reason I mentioned them here...

Why would the resource-list be locked at this point though? If KSP-I Extended can push through some new resources (and delete a couple existing ones that only it uses) and make sure the changes are good-to-go before the deadline, without any input/help from any other modders, then why would it be an issue pushing to get these resources added before the CRP 2.0 development deadline later this week?

Regards,

Northstar

[RoverDude]

Because we have a limited timetable.

Deprecation is fine, but if KSPI suddenly has new stuff that does not fall into the myriad of resources we already have, I'd be surprised, and it can always be a supplementary config (no different than the set of USI resources that are not in CRP yet) - and at that point FreeThinker can bring it up.

[FreeThinker]

Well for the 2 new Resources, Neon and Krypton, I changed their states and density to SuperCritical and removed the postfix ( since they are no longer a Gas).

I think It would be a good idea to do the same for Argon and Xenon. I know XenonGas is an existing stock resource, But I think we can convert all XenonGas to Xenon (without postFix) with a simple MM script. Then we finally have all real Resources in 1 unit / 1 L (except for Antimatter). Realize we only have one shot at this, we cannot do it latter!

Edited March 16, 2015 by FreeThinker

[RoverDude]

Sorry, no messing with stock resources.

Also supercrit messes up the atmospheric harvesting tables. So I am opposed to dropping the noble gasses - you're free to add your supercrit versions.

[FreeThinker]

Sorry, no messing with stock resources.

Also supercrit messes up the atmospheric harvesting tables. So I am opposed to dropping the noble gasses - you're free to add your supercrit versions.

True, I will change it back

[RoverDude]

Also - we do not just have 'one shot' - this has always been an evolving process, we're just doing a fairly large change set right now. As noted, we can always add stuff post-launch.

I'm allowing some extra stuff in here as a courtesy, since normally the criteria are that stuff has to be used by multiple mods to even be on that list in the first place (hence why a decent chunk of my own resources are not there). but I'd rather not this become polluted with stuff in the planning phase, or a large swath of stuff only used by one mod.