FreeThinker

[1.8.1, 1.7.3/1.6.1/1.5.1/1.4.5] KSP Interstellar Extended 1.25 Continued Development Thread

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Version 0.8.9 for Kerbal Space Program 0.90

Released on 2015-04-06

  • CTT balance: Small pebble Bed Reactor available later, upgraded Salt Core reactors available earlier
  • Scooped Nitrogen is stored as Liquid Nitrogen
  • Air scooping now extends up to high space (250K)
  • Hydrogen and Helium can be found in higher concentration above the atmosphere
  • Improved GUI atmospheric scoop
  • Added Liquid Hydrogen to Cryostat
  • Added Cooling for for Liquid Hydrogen / CO2 to Cryostat tank

Edited by FreeThinker

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Try it for yourself

Unie8yT.jpg

I'm scooping hydrogen which I use to thrust my with plasma thrusters until I get into high orbit :cool:

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That's really great!!!

P.S. What PC do you have to support so many mods?

not that many, but I have to use ATM otherwise I would crash after 10 minutes. One problem is that is makes many buttons ugly :(

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You can fix many of them with "Nathen ATM config". Not so many, but not so few... My of will hate me with so many mods, with aggressive ATM too...

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Version 0.8.9 for Kerbal Space Program 0.90

Released on 2015-04-06

  • CTT balance: Small pebble Bed Reactor available later, upgraded Salt Core reactors available earlier
  • Scooped Nitrogen is stored as Liquid Nitrogen
  • Air scooping now extends up to high space (250K)
  • Hydrogen and Helium can be found in higher concentration above the atmosphere
  • Improved GUI atmospheric scoop
  • Added Liquid Hydrogen to Cryostat
  • Added Cooling for for Liquid Hydrogen / CO2 to Cryostat tank

FreeThinker,

Another AWESOME update as always!

You even included some changes that I had meant to suggest, but can't remember ever mentioning yet... Like extending the altitude Propulsive Fluid Accumulators work up until a spacecraft hits "high orbit" around a body (I assume you are using the Low/High boundary- so it will adjust correctly with Real Solar System 6.4x installs?) In real life, the Thermosphere extends up to 500-1000 km (depending on levels of solar activity) so the low/high boundary is a convenient place to draw the line on where PFA's work in KSP as it will make it so players can easily determine if their PFA works with a simple Thermometer part (which will work in Low, but not High Orbit...)

Increasing Hydrogen/Helium abundance in the Thermosphere (above the KSP atmosphere line, but before High Orbit) is both realistic and a good idea from a balance-perspective as well...

Also, what Ec/s values did you use for Liquid Hydrogen and CO2? The Ec/s demands for Hydrogen should be one of the *highest* of any of the cryostat storeable fuels- higher than anything but Helium (which has an even lower boiling-point than Hydrogen: -268.9 C vs. -252.9 C) whereas CO2 has its triple-point at -56.6 C and requires *far less* cooling even than Nitrogen, which boils at -197.795 C (although CO2 has to be pressurized to at least 5.12 atm to remain as a liquid- which should increase tank-mass in direct proportion to the pressure-levels, although the cryostat is already so heavy compared to real life we can probably assume it is already storing fuels at 30-40 atm pressure or more... Even RealFuels Service Modules, which store fuels at 20+ atm of pressure are *much* lighter per liter of volume...)

Regards,

Northstar

- - - Updated - - -

P.S. Would still love to get started on those ISRU reactions... I understand you're still waiting to get data from me on the energy of combustion of Methane and LOX at a temperature of 3000 Kelvin (or a general equation that applies to all temperature-ranges?) I'll be working on that- but could we get started on the ISRU reactions I listed before? I really want to get as many of these in as possible before the 1.0 release, as once 1.0 comes out we'll just be scrambling to make sure everything is ported over correctly for the update to the base-game...

There are several of these that are low-hanging fruit. Especially #7, which is just a matter of implementing a name-change from Monopropellant--> Hydrazine when RealFuels is installed (but in turn enables #8, as Hydrazine can then be easily processed into MMH, UDMH, and Aerozine; which can all be burned with easily-produced N2O4...)

Please let me know your thoughts on this.

Regards,

Northstar

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OK, FreeThinker, having just taken a look at the new EnginePropellants file for the first time, some IMPORTANT thoughts/comments on the REAL fuels (ones with real-life counterparts, i.e. I completely ignore LiquidFuel, LFO, Kethane, and the older NearFuture version of Hydrogen with an arbitrary density- as these can all have basically any stats you want to give them without corresponding to reality...)

(1) The fuel-modes seem to be somewhat ordered in terms of DESCENDING Specific Impulse (starting with LqdHydrogen, which has the highest, and working down to LqdCO2 Cleaning, which has the lowest), but you want them to be ordered in terms of ASCENDING Specific Impulse (that is starting with Lqd CO2 Cleaning and working up to LqdHydrogen). This is because the normal, fuel-efficient way to use a thermal rocket is always to start with the lowest-ISP propellants first, and work through that list to get to the higher-ISP propellants, as you get MUCH better Delta-V for the same spacecraft when you consume your less efficient fuels first... With Thermal Rockets you add in the factor that the lower-ISP fuels generally have better Thrust (and the spacecraft will be heavier at the beginning of a mission) and you have even more incentive to move from lowest to highest ISP...

(2) The "Hydrolox" fuel-mod still contained the "is LFO" code even though ALL the other fuel-modes had it removed. This needs to be removed for the next update of KSP-Interstellar Extended as it messes up the intended ISP and TWR, and causes issues when some fuels have "is LFO" defined and others do not (causing one fuel-mode to overwrite another's intended Thrustmultiplier and ISP...)

(3) The new thermal-decomposition code assumes that Ammonia must be heated to an excessively-high temperature to fully-decompose. The code assumes a 7000 degrees Kelvin heat exchanger is necessary to fully-decompose Ammonia, whereas in reality Ammonia is easily fully-decomposed by a mere 1100 degrees Celsius (1373.15 Kelvin). You need to fix this, and, I suggest, remove the decomposition-curve entirely as it will fully-decompose with *ANY* heat exchanger in KSP-Interstellar Extended (the coldest ones it KSP-I Extended being the experimental fission reactors for CTT which operate at around 1600 K...)

(4) Similarly, Hydrazine fully-decomposes between about 800 and 1000 Kelvin in real life, meaning it will fully-decompose with effectively any nuclear reactor of Microwave Thermal Receiver in the game. But you have it not fully-decomposing until about 6000 Kelvin, which is COMPLETELY unrealistic... I don't think a decomposition-curve is necessary for either Hydrazine or Ammonia (as both fully-decompose at temperatures below the coldest heat exchangers in KSP-Interstellar), it only needlessly complicates the config file...

(5) The temperatures you assume that Water (2000 K) and CO2 (1000 K) start decomposing at are excessively low. In practice, no observable decomposition of either will occur in the very brief time the propellants spend at this temperature before exiting the rocket below at least 3000 Kelvin or hotter...

In short, you got nerf-happy with using the Thermal Decomposition curves to in effect, reduce the Thrust and ISP multipliers for a number of fuels. You need to remove these curves entirely for Ammonia and Hydrazine (as full-decomposition occurs by the temperature of ANY heat exchanger in KSP-Interstellar) and increase the decomposition temperatures for Water and CO2- the latter of which would be used to CLEAN soot off nuclear reactors, not be something that *deposits* it (which is the effect you produce by giving LiquidCO2 a positive SootFactor and a minimum decomposition-temperature of 1000 Kelvin...)

When chemicals start having the OPPOSITE effect of what is expected based on reality (depositing soot rather than removing it, for instance) you know there's something wrong with the balance... You're only going to upset both realists (such as myself- also one of your co-developers...) and veterans used to better fuel-mode performances with these unnecessary and unrealistic nerfs to the fuel-modes through the new Thermal Decomposition curves... Please correct the values as I noted in the 5 comments above...

Regards,

Northstar

P.S. I suggest you actually go and carry out some interplanetary missions in Real Solar System 6.4x or larger before you start assuming things are too powerful. *IF* they are in Stock, it's SUPPOSED to be that way- as KSP Interstellar always is and has been a mod based on introducing essentially realistic technologies and performance into KSP, even if some of them (such as the Warp Drive with which it started) seem over-powered.

I've noticed this again and again with any developer who gets their hands on KSP-Interstellar, they keep trying to fall into the trap of nerfing the performance to seem "balanced" compared to the arbitrary standards of stock and NearFuture performance, the former of which is entirely fictitious and the latter of which is excessively-weak compared to reality when you look at anything they do with nuclear reactors, and considered "useless" even by a great many stock-veterans who have spent much time using that mod's nuclear reactors, including myself... (I can also point you towards some rather derogatory comments about the utility of the excessively-nerfed NearFuture mod by players like Geschosskopf, after his experiences with the "Argonian"...)

Trust me, the nerfing-trap is NOT one you want to fall into. Stick with the realistic performance, and let REALITY dictate your balance- you'll end up getting something that is both fun and believable in the end, regardless of how "balanced" it seems compared to stock performance... (if players want to fly around a miniature solar system with little green aliens, then who are we to tell them they can't have realistic rocket performance? Players can already impose their own arbitrary restrictions or nerfs with the tweakable parts of the KSP-I Extended config if they want, but imposing realistic performance is MUCH harder to do after-the-fact without extensive research by players if the mod wasn't already designed that way to begin with...)

- - - Updated - - -

Ergh, correction, CO2 doesn't thermally decompose until temperatures of at least 3200 K, and only then at pressures approaching 100 atm (such as on the leading-edge of a capsule during re-entry...) In practice not until at least 5000 K at the pressures of a Nuclear Thermal Rocket, with an upper temperature of 7000 K seeming appropriate:

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0CCQQFjAA&url=http%3A%2F%2Fwww.researchgate.net%2Fprofile%2FMatthew_Oehlschlaeger%2Fpublication%2F241688099_Carbon_Dioxide_Thermal_Decomposition_Observation_of_Incubation%2Flinks%2F00b4951ca0124e1e66000000.pdf&ei=gScjVceJH8SHsAWZrIDoBQ&usg=AFQjCNEXucnCWbdaWOAWt4_UGXWhCmXaPg&bvm=bv.89947451,d.b2w&cad=rja

Water, on the other hand, thermally decomposes a bit colder- starting to rapidly decompose at about 2200 K (it slowly decomposes much colder), with more than half of the molecules decomposing at 3000 K... However this is after PROLONGED incubation at these temperatures. When rapidly moving through a nuclear thermal rocket, you're probably not going to see appreciable decomposition in that brief time-frame below about 3000 K, and not full-decomposition until at least 4200 K or so...

http://en.wikipedia.org/wiki/Water_splitting#Thermal_decomposition_of_water

Finally, Methane isn't going to require temperatures of 15,000 K to fully-decompose. It should be fully-decomposed by around 3000 K, considering you can quite rapidly decompose it after about 1000 K... So, it's only not going to fully-decompose in some of the coldest heat exchangers in KSP-Interstellar... It's frankly kind of silly that it currently doesn't start decomposing until a higher temperature than CO2 in the mod... (1500 vs 1000 K)

Summary of appropriate decomposition temperature-ranges for Thermal Rockets:

CO2: 5000-7000 K (NO soot deposition below 5000 K! CLEANS soot below 3000 K...)

Water: 2200-4200 K

Methane: 1000-3000 K

Regards,

Northstar

Edited by Northstar1989

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I´m the only on with the problem that the Megawatt buffer do´t charge?

Reactor run´s fine, but throttle down, so the Megawatt buffer´s do´t charge.

Version0.8.8 & 0.8.9, 0.8.2 has been fine.

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I have Near Future Electrical installed and whenever I try to use a fusion reactor, it seems to need over a hundred times as much power as it produces. Is this intended, or do the power costs not get rescaled with the output?

Also, there seems to be a bug with microwave transmission: In my tests, if a deployable transceiver is attached directly to a generator, the generator becomes unable to produce any power.

Edited by MrNukealizer

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If I might make a suggestion: I would lime to see an increase in the large black wing radiators (the ones that don't fold) so that a single, upgraded fusion reactor only needs 2 of them instead of the current 4. This would make them easier to incorporate into designs without the result looking horrible.

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If I might make a suggestion: I would lime to see an increase in the large black wing radiators (the ones that don't fold) so that a single, upgraded fusion reactor only needs 2 of them instead of the current 4. This would make them easier to incorporate into designs without the result looking horrible.

Current thermal radiation is based on real-world performance: we even reflect the approximately 70% higher thermal emissivity (compared to any normal material) that is possible with graphene through meta-material properties...

Regards,

Northstar

- - - Updated - - -

You do realize that the current CRP has been using the 1000kg/m3 definition since CRP first came out, and that definition came from TAC-LS.

From CRP:


RESOURCE_DEFINITION
{
name = Water
density = 0.0010000000
flowMode = ALL_VESSEL
transfer = PUMP
isTweakable = true
unitCost = 0.0008
}

From TAC-LS:


RESOURCE_DEFINITION
{
name = Water
density = 0.001
flowMode = ALL_VESSEL
transfer = PUMP
isTweakable = true
unitCost = 0.0008
}

I think Taranis is owed an apology.

(Edit for completeness)

KSPI LqdWater:


RESOURCE_DEFINITION
{
name = LqdWater
density = 0.001
flowMode = STACK_PRIORITY_SEARCH
transfer = PUMP
isTweakable = true
unitCost = 0.000001
}

I missed this before, and only came across it now by a search...

Yes, it does appear my information was outdated- I know that TACLS did at one time use a different density (most likely by not assuming 1 units = 1 liter). It appears it has been using the correct density for some time now, however, and the only real issue with it is the absolutely insane cost it has of $0.80/liter in 1965 dollars (using the 1 Fund = $1000 1965 USD convention...) making it come out to $5.96/liter in 2015 dollars- which is more expensive than bottled water! (which is sold at ENORMOUS profit :) )

Regards,

Northstar

- - - Updated - - -

@FreeThinker,

It appears there is currently an issue with the way Propulsive Fluid Accumulators work, introduced by your recent increase to the max altitude they work at:

umB3cd7.jpg

Propulsive Fluid Accumulators no longer work below 100 km! (testing by raising this satellite's altitude revealed that to be the cut-off point...) It appears you also introduced a minimum collection-altitude, possibly intentionally?

This is not actually realistic- while in real life, PFA's operate at a minimum altitude of 100 km, Earth's atmosphere is much taller than Kerbin's! (and indeed the proper "atmosphere" extends slightly ABOVE 100 km in full-scale RSS!)

They only operate this high up because drag rapidly increases below the Thermosphere, making it difficult to combat it effectively in the thrust-range of an electric thruster... (with a powerful enough electric thruster, you *can* collect below the Thermosphere, just as you can do in KSP-Interstellar within the proper atmosphere given enough electric power available to a plasma thruster...)

The "edge" of an atmosphere in KSP is the best analog to the edge of the Thermosphere, being at approximately the correct pressure for the point at which drag rapidly increases and the Thermospehre ends (when descending)...

Thus, there is NO NEED for a "minimum" altitude for Propulsive Fluid Accumulators in KSP- and it also creates potential problems with trying to collect around planets other than Kerbin (such as Duna, for instance) where the atmosphere begins at a different height (Propulsive Fluid Accumulators could operate much lower around Mars, for instance, due to the thinner atmosphere and lower orbital velocity...)

At least PFA's still currently work quite well within the actual atmosphere (in RSS 6.4x it starts at 91 km), if you can find enough power to combat the drag, which is realistic...

aczSfxh.jpg

The problem with this being, of course, you cannot use time-warp within the proper atmosphere.

Summary:

- Please remove the minimum collection-height (as long as a PFA is above the "atmosphere" in KSP it should be able to collect in extra-atmospheric mode corresponding to scooping inside the Thermosphere...) It is both annoying for players and unrealistic.

Regards,

Northstar

Edited by Northstar1989

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Finally, Methane isn't going to require temperatures of 15,000 K to fully-decompose. It should be fully-decomposed by around 3000 K, considering you can quite rapidly decompose it after about 1000 K... So, it's only not going to fully-decompose in some of the coldest heat exchangers in KSP-Interstellar... It's frankly kind of silly that it currently doesn't start decomposing until a higher temperature than CO2 in the mod... (1500 vs 1000 K)

Well you told me yourself because of the short time the Propellant is heated, it does not have enough time to decompose and therefore you estimated approximately only 10% is decomposed at 3000K. I simply extended your reasoning trying to predict at which temperature decomposition of 100% is guaranteed when heated for a fraction of a second. Note I also found some documents stating that at 5000K K, and enough incubation time only, 50% would decompose. So clearly you need a much higher temerature than 5000K to get the same result when heated for only a short time. The same argument can be used to explain other prepellants temperature ranges.

Trust me, the nerfing-trap is NOT one you want to fall into. Stick with the realistic performance, and let REALITY dictate your balance- you'll end up getting something that is both fun and believable in the end, regardless of how "balanced" it seems compared to stock performance... (if players want to fly around a miniature solar system with little green aliens, then who are we to tell them they can't have realistic rocket performance? Players can already impose their own arbitrary restrictions or nerfs with the tweakable parts of the KSP-I Extended config if they want, but imposing realistic performance is MUCH harder to do after-the-fact without extensive research by players if the mod wasn't already designed that way to begin with...)

I admid the decompostion mechanic is a conveniant way for me to balance the reactors, giving reactors that are hotter and more advanced a distinct advantage with exotic propellants like methane. This will create a more balanced progression from an traditional but difficult to store hydrogen/oxygen to more heat dependant, but easier to store propellants.

I have Near Future Electrical installed and whenever I try to use a fusion reactor, it seems to need over a hundred times as much power as it produces. Is this intended, or do the power costs not get rescaled with the output?

Also, there seems to be a bug with microwave transmission: In my tests, if a deployable transceiver is attached directly to a generator, the generator becomes unable to produce any power.

Looks like a NFT-E mode oversight of me. For the NFT-E mode, I reduced Power output of all reactors by a factor of 500 but I might have forgoten to lower power requirements as well, resulting in insane power requirements for fusion reactors compaired to power output. Overal I increased the power requirements to 10% of reactor power output, meaning you need a large large amount of power to start fusion, but once started up, it should supply plenty of energy to generate a large surplus of electric power.

- - - Updated - - -

Propulsive Fluid Accumulators no longer work below 100 km! (testing by raising this satellite's altitude revealed that to be the cut-off point...) It appears you also introduced a minimum collection-altitude, possibly intentionally?

Well it's not intended, The idea was to make it more flexable and intresting, not more restrictive. I will look into it. I will also improve the GUI, this way you will know if the current orbit is effective for resource accumulation.

Edit: Fixed the problem in 0.8.10

- - - Updated - - -

Also, what Ec/s values did you use for Liquid Hydrogen and CO2? The Ec/s demands for Hydrogen should be one of the *highest* of any of the cryostat storeable fuels- higher than anything but Helium (which has an even lower boiling-point than Hydrogen: -268.9 C vs. -252.9 C) whereas CO2 has its triple-point at -56.6 C and requires *far less* cooling even than Nitrogen, which boils at -197.795 C (although CO2 has to be pressurized to at least 5.12 atm to remain as a liquid- which should increase tank-mass in direct proportion to the pressure-levels, although the cryostat is already so heavy compared to real life we can probably assume it is already storing fuels at 30-40 atm pressure or more... Even RealFuels Service Modules, which store fuels at 20+ atm of pressure are *much* lighter per liter of volume...)

Depending on the boiling point I gave them higher or lower power requirements. Right now for the 16000 liter tank it is 20, 15, 10 Ec/s (Hydrogen, Nitrogen, CO2). Regarding the exact power cost, I think we need some more accurate estimations. Besides cooling, I believe Hydrogen tanks should also always leak a little, even with enough power due to the small molecules peneatrating the tank wall. I need some good estimes of how much. This is already a existing feature of the Cryostat tanks but not applied. Also note I can already vary the power requirments depending on how much much the tank is filled yet. I also have a idea to modify the power cost depending on the temperature of the tank, that way, it would require significantly less power in the shade or far away from the sun. The opposite, will also be true, going to Moho, will require a lot of more power to keep your tanks cool. To make it look more reralistic, I hope to use the new ammonia radiator models which still need to be textured, then it would truely look like in real life!

- - - Updated - - -

(1) The fuel-modes seem to be somewhat ordered in terms of DESCENDING Specific Impulse (starting with LqdHydrogen, which has the highest, and working down to LqdCO2 Cleaning, which has the lowest), but you want them to be ordered in terms of ASCENDING Specific Impulse (that is starting with Lqd CO2 Cleaning and working up to LqdHydrogen). This is because the normal, fuel-efficient way to use a thermal rocket is always to start with the lowest-ISP propellants first, and work through that list to get to the higher-ISP propellants, as you get MUCH better Delta-V for the same spacecraft when you consume your less efficient fuels first... With Thermal Rockets you add in the factor that the lower-ISP fuels generally have better Thrust (and the spacecraft will be heavier at the beginning of a mission) and you have even more incentive to move from lowest to highest ISP...

Well I mainly kept this sorting for historical reasons, but I'm not pleased how it works now. One of the problems is that switching during flight can have catastrophic consequences, like killing your crew. I play with TAC life-support and I have already had several instances where I accidently used the crew water as a propellant, killing them after a few days when they die from lack of water. I need somehow to disable certain propellant from usage, especially when the lives of your crew depend on it. This seriously need to improve. preferable a specialized windows that allows you to control the order, enable/disable auto switching and the ability to reserve a certain amount for other usage (like life support).

- - - Updated - - -

Version 0.8.10 for Kerbal Space Program 0.90

Released on 2015-04-07

  • Fixed Minumum Height Propulsive Fluid Accumulators

- - - Updated - - -

Yes, it does appear my information was outdated- I know that TACLS did at one time use a different density (most likely by not assuming 1 units = 1 liter). It appears it has been using the correct density for some time now, however, and the only real issue with it is the absolutely insane cost it has of $0.80/liter in 1965 dollars (using the 1 Fund = $1000 1965 USD convention...) making it come out to $5.96/liter in 2015 dollars- which is more expensive than bottled water! (which is sold at ENORMOUS profit :) )

Perhaps the water cost is for distilled water which is considerably more expansive to produce.

- - - Updated - - -

If I might make a suggestion: I would lime to see an increase in the large black wing radiators (the ones that don't fold) so that a single, upgraded fusion reactor only needs 2 of them instead of the current 4. This would make them easier to incorporate into designs without the result looking horrible.

Those radiators are actualy too small for their cooling effect, that's why it is so high in the tech tree. You want to make it worse? I think I rather lower their mass and surface area than increase it.

- - - Updated - - -

I´m the only on with the problem that the Megawatt buffer do´t charge?

Reactor run´s fine, but throttle down, so the Megawatt buffer´s do´t charge.

Version0.8.8 & 0.8.9, 0.8.2 has been fine.

Well it is intended they buffer doesn't get filled. They were acting like super powerfull, lossless, long lasting capacitators. Who needs batteries if you can store many gigawatt for free? The main reason why they are so large is that they are needed to provide enough power durring high timewarp. This is due to the way Ksp functions at high warp. At high timewarp, you need a 1000000 larger buffer. The problem is that even if you switched power off, you had enough power to run life support for several thousant of years. To fix it, instead of a static ceiling, I danamicly change the ceiling depending on timewarp and maximum power output. This means you ceiling will increase when you go into warp and shrink then you get out of warp. The difference in power is automaticly added or removed.

Edited by FreeThinker

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Well you told me yourself because of the short time the Propellant is heated, it does not have enough time to decompose and therefore you estimated approximately only 10% is decomposed at 3000K.

OOPS! That I did! It appears my previous estimates were quite a bit off, and I refined them after doing some more research... (my more recent estimates are probably more accurate- as they are based on more data) Sorry about that!

I simply extended your reasoning trying to predict at which temperature decomposition of 100% is guaranteed when heated for a fraction of a second. Note I also found some documents stating that at 5000K K, and enough incubation time only, 50% would decompose.

50,000 K? Ummm, show me those documents...

So clearly you need a much higher temerature than 5000K to get the same result when heated for only a fraction of time. The same aregument can be used for other prepellants.

I really need to see these documents. Is it 5000 K or 50,000 K (50,000 K is halfway to the 100,000 K at which nuclear fusion first starts to occur!)

I admid the decompostion mechanic is also a conveniant way for me to balance the reactors, giving reactor that are hotter and more advanced a distinct advantage with exotic propellants like ammonia and methane.

Ammonia isn't an exotic propellant. It's considered one of the most likely propellants for NTR's in real life, and appears in SciFi as far back as the sequel to 2001: A Space Oddessy. It's easily decomposed, and along with Hydrazine, should be fully-decomposed in almost any reactor in KSP-I (except the "experimental" fission reactors that only operate at around 1600K- they might not decompose a very small fraction of the Ammonia or Hydrazine they heat, but will still break down the vast majority...)

Well it's not intended, The idea was to make it more flexable and intresting, not more restrictive. I will look into it. I will also improve the GUI, this way you will know if the current orbit is effective for resource accumulation.

Edit: Fixed the problem in 0.8.10

Glad to know it's fixed, because it turns out the PFA's don't actually work in time-warp at ANY altitude in 0.8.09:

1kSakvD.jpg

Here my PFA was, near the maximum altitude they should work at in stock (250 km) although less than the appropriate cap in RSS 6.4x (around 325 km) and it still wasn't working in time-warp!

Depending on the boiling point I gave them higher or lower power requirements. Right now for the 16000 liter tank it is 20, 15, 10 Ec/s (Hydrogen, Nitrogen, CO2). Regarding the exact power cost, I think we need some more accurate estimations. Besides cooling, I believe Hydrogen tanks should also always leak a little, even with enough power due to the small molecules peneatrating the tank wall. I need some good estimes of how much. This is already a existing feature of the Cryostat tanks but not applied. Also note I can already vary the power requirments depending on how much much the tank is filled yet. I also have a idea to modify the power cost depending on the temperature of the tank, that way, it would require significantly less power in the shade or far away from the sun. The opposite, will also be true, going to Moho, will require a lot of more power to keep your tanks cool. To make it look more reralistic, I hope to use the new ammonia radiator models which still need to be textured, then it would truely look like in real life!

Actually, the cooling-cost for a tank is completely unrelated to how full it is. It is related to one thing only: the rate at which heat leaks into it (which is entirely determined by the surface area). For that matter the rate at which cryogenics boil off when NOT cooled is also related almost entirely to the surface area (bigger tanks tend to boil off a bit more slowly due to their thinker walls- a tank with 8 times the volume will have 4 times the surface area and walls twice as thick- for exactly the same ratio of tank mass to volume... But thicker walls act as better insulators...

All this means that it can sometimes be more effective to split the same amount of fuel into a larger number of smaller tanks, even though each of the smaller tanks requires more electricity relative to its volume (I hope this relationship between tank volume and electrical requirements being non-linear is still represented with the new tank types, as it was with the Nitrogen tanks), if some of the fuel will be used earlier in the mission and some later- so you don't have to cool as much tank volume later in the mission...

Well I mainly kept this sorting for historical reasons, but I'm not pleased how it works now. One of the problems is that switching during flight can have catastrophic consequences, like killing your crew. I play with TAC life-support and I have already had several instances where I accidently used the crew water as a propellant, killing them after a few days when they die from lack of water. I need somehow to disable certain propellant from usage, especially when the lives of your crew depend on it. This seriously need to improve. preferable a specialized windows that allows you to control the order, enable/disable auto switching and the ability to reserve a certain amount for other usage (like life support).

There is already a way to reserve a certain amount of other uses, and always has- simply forbid certain tanks before performing a burn by right-clicking them and clicking the appropriate arrow next to the fill-gauge for that tank... As for auto-switching, what auto-switching? I've never had my fuels automatically switch during flight- I always have to toggle it manually...

Version 0.8.10 for Kerbal Space Program 0.90

Released on 2015-04-07

  • Fixed Minumum Height Propulsive Fluid Accumulators

AWESOME!

Perhaps the water cost is for distilled water which is considerably more expansive to produce.

Distilling water might increase its cost maybe 10-fold, if that. It isn't exactly an expensive process- I was trusted to operate a small distiller as a TA in my high school chemistry lab back when I was in high school... The equipment to do it isn't hugely expensive- and gets much cheaper for the capacity the more you scale it up...

The cost of Water in TACLS ($5.76/liter) is already more than 100x what it should be based on real life costs. The value KSP-I uses is fine if we assume highly-expensive filtering processes were used.

Those radiators are actualy too small for their cooling effect, that's why it is so high in the tech tree. You want to make it worse? I think I rather lower their mass as surface area than increase it.

Hmmm, indeed there does seem to be a mis-match between the radiator "surface area" value in the config and the actual size of the physical model. It's not that they radiate too much heat for their surface area (according to the part config), those values are realistic for all radiators as I explained before- it's that the model is too small for the surface area we assign it...

But yeah, a decrease in the assigned surface area to match the model, or an upscaling of the model to match the surface area might be in order...

Well it is intended they buffer doesn't get filled. They were acting like super powerfull, lossless, long lasting capacitators. Who needs batteries if you can store many gigawatt for free? The main reason why they are so large is that they are needed to provide enough power durring high warp. Tjhis is due to thr way Ksp function at high warp. To fix it, instead of a static ceiling, I danamicly change the ceiling depending on timewarp and maximum power output. This means you ceiling will increase when you go into warp and shrink then you get out of warp. The difference in power is automaticly added or removed.

Interesting. Cool. :cool:

Regards,

Northstar

Edited by Northstar1989

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50,000 K? Ummm, show me those documents...

No I mend 5000K and can't seem to find the document again

Edited by FreeThinker

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Also, some eye-candy to make up for my recent grumpiness a bit:

5ZkxA9V.png

This is the Hydrazine-propelled Nuclear Thermal Spaceplane I designed and flew to orbit in RSS 6.4x that I was talking about needing the Hydrazine fuel-mode for before (well, technically, this is a later redesign of the version that was waiting when I wrote that...) It is shown here de-orbiting after a successful mission to deploy part of the Propulsive Fluid Acccumulator shown earlier... (I launched the probe core, heat radiators, and additional LqdNitrogen tankage in a separate launch)

It won't work anymore if Hydrazine is made to (unrealistically) not fully-decay in a 2750 K nuclear reactor though (the temperature of the main reactor after a bit of WasteHeat accumulation).

Hydrazine is already routinely used in RCS thrusters that operate at a fraction of that temperature (and basically rely on catalyst beds to reduce the activation energy), and once can rapidly and fully thermally decompose Hydrazine by around 1000 K even without a catalyst (remember, its flash point is a mere 52 C). There's no need to include a Thermal Decomposition curve for either Hydrazine or Ammonia in KSP-I Extended... Especially considering the colder NTR's might well include metal catalyst-surfaces somewhere along the propellant path after the heat-exchanger: Ammonia, Hydrazine, etc. breakdown are easily catalyzed by Iron alloys, for instance... Adding a thin layer of high-temperature steel alloys along the exhaust pathway is not particularly difficult...

Regards,

Northstar

Edited by Northstar1989

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All this means that it can sometimes be more effective to split the same amount of fuel into a larger number of smaller tanks, even though each of the smaller tanks requires more electricity relative to its volume (I hope this relationship between tank volume and electrical requirements being non-linear is still represented with the new tank types, as it was with the Nitrogen tanks), if some of the fuel will be used earlier in the mission and some later- so you don't have to cool as much tank volume later in the mission...

Sorry I don't understand. Smaller tanks would increase the total amount of tanks, and would therefore increase power cost and leaking. They most efective meathod to transport hydrogen would be a single ball shaped tank

- - - Updated - - -

It won't work anymore if Hydrazine is made to (unrealistically) not fully-decay in a 2750 K nuclear reactor though (the temperature of the main reactor after a bit of WasteHeat accumulation).

Alright, now answer me the following question: If Ammonia would fully decompose at low temperatures (<3000K) Why would anyone bother developing Engines with Hydrolox? There must be inherent problems with the fuel otherwise we would already be developed and used. My best guess is that to decompose you need significant higher temperatures which is not possible right now.

Edit, perhas another potential problem of ammonia is it's toxicity

Nuclear thermal engines use the heat of a nuclear reactor to heat a propellant. Although early Russian designs used ammonia or an ammonia/alcohol mixture as propellant, the ideal working fluid for space applications is the liquid form of the lightest element, hydrogen. Although successfully ground-tested in both Russia, they have never been flown due primarily to environmental and safety concerns.

It is a relatively high-boiling gas with a vapour pressure of 8.7 bar at 20 deg C. Ammonia. is toxic, and will dissolve easily in water. It will form flammable and explosive mixtures with air. Although ammonia itself is toxic, the exhaust gases from the combustion of ammonia and oxygen are not. Ammonia is produced by a Haber-Bosch process, in which the elements, nitrogen and hydrogen, are united at a temperature of 500 to 600 deg C and a. pressure of approximately 200 bar in the presence of a promoted iron catalyst. It is estimated that 4 million tonnes of anhydrous synthetic ammonia were produced in 1959 in the United States, at which time the price of tank-car quantities of refrigeration-grade anhydrous ammonia was $ 80 per tonne.

Oxidizer: Nuclear. Oxidizer: Nuclear. Fuel: Ammonia. Fuel: Ammonia+Alcohol. Propellant Formulation: Nuclear/NH3+Alcohol (C2H5OH). Fuel Density: 0.604 g/cc. Fuel Freezing Point: -78 deg C. Fuel Boiling Point: -33 deg C.

If ammonia is so toxit, perhaps that explains why they didn't even dare to use Hydrazine

- - - Updated - - -

Edit: intresting document which mentions ammonia

- - - Updated - - -

Edit: Found an intresting discussion regarding the problems of ammonia

>Lumping water and ammonia together is a bit unfair

>to ammonia. Ammonia decomposes at high temperature

>into nitrogen and hydrogen, giving a mixture with

>an effective molecular weight of 8.25. Water remains

>mostly intact, with a MW of 18.

True, although the ammonia decomposition reaction is discouraged by high

pressure, and is also endothermic (absorbs some heat). The experience of

using ammonia as a fuel in chemical rockets has not been a happy one, with

many development difficulties, although it's hard to say whether that

would carry over to NTRs.

And even at 8.25, the advantage over chemical rockets is rather limited.

(For those who aren't up on this... The key problem is that solid-core

nuclear thermal rockets must be run cool enough that the core doesn't

melt, while chemical rockets are under no such constraint; temperatures in

a high-pressure LOX/LH2 flame are very high. *The* big advantage of

solid-core nuclear rockets is that their exhaust is all hydrogen, which

gives very high performance because of its very low molecular weight and

some other reasons, while the hotter chemical rockets have to accept an

exhaust with a lot of heavier and less helpful molecules.)

>Also, water is

>oxidizing, and will react with the engine components

>(like carbon), which forces the use of oxidation-

>resistant engine components, limiting the temperature

>that can be achieved.

As I recall, the problem is not so much that it's hard to build an

oxidation-resistant NTR, as that it's hard to build one that can run well

on *both* oxidizing and reducing mixtures. That is, you can probably

build one which will run hot on water (or carbon dioxide, another

propellant of interest that turns oxidizing at high temperatures), but you

can't run the same engine hot on hydrogen or ammonia. So there hasn't

been much interest in trying.

Edited by FreeThinker

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It won't work anymore if Hydrazine is made to (unrealistically) not fully-decay in a 2750 K nuclear reactor though (the temperature of the main reactor after a bit of WasteHeat accumulation).

Well there is one way I could improve it. Instead of calculating the decomposition fraction as a linear function, I might add an exponential component which allow it to grow faster in the beginning.

Like decompositionFraction = LinearTemperatureFraction ^ 0.5 . This means you get significantly higher Isp/thrust al lower temeratures but to get maximum performance you still need higher temperatures

For your 2750K engines that would result in a decompositionFraction = ((3750 - 600) / (6000 - 600)) exp 0.5 = 0.47 ^ 0.5 = 0.687 (which is 46% higher from what you have now)

Edit: Because methane decomposition is chance related, perhaps I can improve it further by using a Gausian function

The formation of soot particles depends on a wide range of parameters including

temperature, pressure, and fuel type. Temperature plays a particularly important

role among these parameters. Several experimental measurements, both in laminar

premixed ames [17, 18, 206] and in shock tubes [90, 96, 77], have shown that soot

volume fraction exhibits a so-called \bell shaped" curve as a function of temperature.

At low temperatures, soot volume fraction increases with increasing temperature.

p(x) = exp(-(x-mu)^2/(2*sigma^2))/sqrt(2*pi*sigma^2)

# where mu is the center of the bell curve, and sigma is proportional to its "width"

Edited by FreeThinker

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Regarding using water as a propelant in solid cores, I think we should perhaps only allow with some reducing agent like Hydrogen, Hydrozine or Ammonia disolved in the water as an antioxidiser, otherwise the water will start to oxidising the heat exchanger with resulting nuclear fuel leaking. Gas core reactors would on the other hand not have this problem, or allow it only with Kerbal Engeneers with High enough Stupidity ;)

Edited by FreeThinker

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The cost of Water in TACLS ($5.76/liter) is already more than 100x what it should be based on real life costs. The value KSP-I uses is fine if we assume highly-expensive filtering processes were used.

Perhaps he tried to compensate for the fact that Kerbal require very little water to survice. To kerbals we are like Giants which are heavy and require a huge amount of resource to maintain. Which made me think, why hell are we sending heavy resource hungry full sized Humans into space, when we can do it for 1/4 of the cost by sending little people (midgets/dwarves/halflings)? That would reduce cost for "manned" space exploration by a huge degree!!

Off cource sending kerbal sized little people wouldn't be as cool as sending full sized humans, but as long as the are proportionaly correct, the people don't have to know :P

Edited by FreeThinker

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Current thermal radiation is based on real-world performance: we even reflect the approximately 70% higher thermal emissivity (compared to any normal material) that is possible with graphene through meta-material properties...

Regards,

Northstar

- - - Updated - - -

I missed this before, and only came across it now by a search...

Yes, it does appear my information was outdated- I know that TACLS did at one time use a different density (most likely by not assuming 1 units = 1 liter). It appears it has been using the correct density for some time now, however, and the only real issue with it is the absolutely insane cost it has of $0.80/liter in 1965 dollars (using the 1 Fund = $1000 1965 USD convention...) making it come out to $5.96/liter in 2015 dollars- which is more expensive than bottled water! (which is sold at ENORMOUS profit :) )

Regards,

Northstar

Oh...Oh well. I will just have to get better at hiding them then. Thank you.

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[h=2]Version 0.8.11 for Kerbal Space Program 0.90[/h] Released on 2015-04-07

  • Fixes Fusion power Requirements for NFT-E / SETI
  • Increased MegaWatt storage to at least 5% of overall power reactor output

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Hi.

why do my nuclear reactors have anemic sub-10kW thermal power output?

I deleted all my Near Future files, reinstalled KSPI-E, created a new save and selected the KSPI 0.90 techtree.... To no avail. I'm sitting in the VAB with a 2.5 ton Sethlans fission reactor that produces only 8kW thermal power.

what should I do?

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SETI-BalanceMod v0.8.8

Removed ProceduralParts dependencies

This allows players to avoid the ProceduralParts/TweakScale bug and makes SETI a more viable choice for existing games, especially based on the CommunityTechTree.

Together, those factors allow for SETI-KSPIextended joint usage.

Only some minor surface optimizations still to do for full support, like naming scheme and maybe very minor technode shuffling. I m still searching for an adequate washer component, but since procedural parts are no longer required, this is not crucial anymore.

Please note, that it might take some time until the CKAN dependency list is updated.

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Hi.

why do my nuclear reactors have anemic sub-10kW thermal power output?

I deleted all my Near Future files, reinstalled KSPI-E, created a new save and selected the KSPI 0.90 techtree.... To no avail. I'm sitting in the VAB with a 2.5 ton Sethlans fission reactor that produces only 8kW thermal power.

what should I do?

It should be at least 4MW, somehow the reduction is applied multiple times. weird

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