[0.25]KSP Interstellar (Magnetic Nozzles, ISRU Revamp) Version 0.13

[Fractal_UK]

Any news if the patch for it will be released soon ?

0.8 is now feature complete so the vast majority of the work is now done. The remaining work lies in creating resource maps for some of the celestial bodies, testing (+bugfixing) and gameplay and balance tweaks. The final release will depend on how smoothly this all goes but we're certainly nearly there.

[Saphykitten]

0.8 is now feature complete so the vast majority of the work is now done. The remaining work lies in creating resource maps for some of the celestial bodies, testing (+bugfixing) and gameplay and balance tweaks. The final release will depend on how smoothly this all goes but we're certainly nearly there.

Cant wait!

[RabidMonkey]

0.8 is now feature complete so the vast majority of the work is now done. The remaining work lies in creating resource maps for some of the celestial bodies, testing (+bugfixing) and gameplay and balance tweaks. The final release will depend on how smoothly this all goes but we're certainly nearly there.

Commence frantic refreshing...NOW.

[Northstar1989]

NearFuture mod also has Argon- but it has an entirely different (much lower) mass-per-unit, and is used in different engines.

Nonetheless, is there any chance that the atmospheric scooping system might be made compatible with producing NearFuture mod ArgonGas as well> (with production volumes adjusted for the much lower mass-per-unit of the fuel).

[Fido488]

Do you have/do you need beta testers or is it all just you?

[Kielm]

Hello!

TL:DR version:

1) Stock nuclear engines seem to be better than the ones in this mod until fusion power is researched. What's their use?

2) How do I obtain deuterium?

---Wall of text warning---

So I've been using this mod for some time and been enjoying it. Having worked through the tech tree in career mode in 0.7.4 I'm having some trouble finding useful applications for Nuclear-powered rockets.

Before fusion power, the thermal rocket configuration for a 1.25 nuclear reactor seems to provide less ISP and less thrust than a stock nuclear engine, at roughly the same weight, but with the added benefit of producing power. Using plasma thrusters increases the ISP but makes the thrust so low that performing interstellar manoeuvres becomes extremely time-consuming.

In short, the only useful application I've found for nuclear reactors is power generation for science labs. Thermal rocket thrust and ISP are too low to either land on the majority of planets or outperform stock nuclear engines.

I've just researched fusion power so this is about to change, but I'm wondering if anyone else has any ideas about using various sizes of nuclear reactors with different configurations of thermal nozzles/plasma thrusters? I've played around a bit but haven't found any configuration that seems to just... 'work'.

Finally, Engineer Redux seems to be having trouble determining delta-v with the vista engine, and I'm not sure how long the tritium/deut will last. I can breed tritium in the reactor but do I need to electrolyse for deuterium using the science lab or harvest with atmospheric scoops? It's going to be hard enough getting a 3.75m nuclear reactor powered vessel off of Kerbin without even thinking about landing it somewhere as well!

Thanks in advance - great mod with some challenging stuff in it.

[AdmiralTigerclaw]

Yeah, one thing that bugs me about the nuclear thermal engines is that you have to plant the engines on the reactor. Be it the nuclear turbojet or the thermal rocket... you just can't use an effective multi-engine config for it. (Because you weigh it down with several huge reactors.) I understand the logic of course: Direct contact for heat transfer.

Be nice if we could have a way to 'send' thermal energy to functional parts. Or even just the thermal turbojet. You can flow intake air to the reactor and then pipe that superheated air to exhaust nozzles. But of course, the further you pipe it, the most heat is lost into surrounding parts and all that mathematical thermodynamics fun. I just think thermal engines should be able to share reactor heat without having to be bolted right to it. (Even if you have to reduce the effectiveness of the reactors because of the heat-sharing dividing the thermal energy resource.)

[Patupi]

I think a 'heat pipe' is in the works. Not sure if Fractal_UK got it working for the upcoming 0.8 release or not, but he has talked about it.

[Umlüx]

once you have the vista, everything else is practically obsolete.

just calculated the dV of my newest IP ship... althought it has a much better fuel/payload ratio than my old nerva driven ships, it has 4x to 5x the dV

i think with 28.000dV you could visit every planet and back again. now if only the AM tank wouldn't slowly drain the power i could go on forever

[AndreyATGB]

once you have the vista, everything else is practically obsolete.

just calculated the dV of my newest IP ship... althought it has a much better fuel/payload ratio than my old nerva driven ships, it has 4x to 5x the dV

i think with 28.000dV you could visit every planet and back again. now if only the AM tank wouldn't slowly drain the power i could go on forever

You get up to 50k dV at about 40% thrust. That sounds like it would be possible to visit everything, but the reactor will run out of Uranium long before you get to all the planets.

[Umlüx]

i am running with antimatter and have some collectors on the ship. but i don't think it is enough to prevent the tank from getting drained..

now this would be a nice new chart.. how many collectors do you need in each SOI to keep the tanks topped? i don't want to put half a dozen giant solarpanels on my ship to charge the tank..

[Eadrom]

If I remember correctly, I had an antimatter powered research ship with 2 antimatter collectors. I believe just two was enough to gain antimatter at optimal altitude around the larger planets (Eve, Kerbin, Jool).

You could go Kerbin->Moho->Eve->Duna->Dres->Jool->Eeloo. Depending on how long you spend at Jool waiting for a phase angle to Eeloo, you may or may not want to top off on antimatter at Jool after visiting Eeloo before heading home.

I had an antimatter+plasma thruster+LF setup with ~38k delta V on another ship design and it only required 7500 antimatter to power the reactor at 100% while at full throttle for all 38k delta V. Fairly certain that if you filled one of the smallest antimatter tanks, you could easily go on a tour of all the planets and moons without needing to refuel at all. One thing to consider is that tossing on a 62.5cm nuke reactor/generator or two will take care of your ships power needs for science transmitting and whatever else you need power for as well as keeping your antimatter containment fields fully powered. That's a MUCH lower mass solution that loading up on antimatter collectors. Additionally, those little nuke reactors will last quite some time. If I've done my math correctly, they will last at most 26.3 years or as little as 7.9 years if you are running them hotter than base of 30%. Cut those times to 1/3 if you upgraded them (8.8 and 2.6 years respectively). Granted, you can drastically increase run times both by using a science lab on the ship to reprocess fuel or in the next patch you can use a kerbal to refuel using the upcoming nuke fuel tanks.

Throw on one or two antimatter collectors to grab a trickle charge of antimatter whilst you are waiting for phase angles and just use one or two of the smallest nuke reactor/generator combos to power your ship. Should work out to be one of the more mass efficient solutions to your question.

Edited November 21, 2013 by Eadrom

[Umlüx]

thanks! i'll look into this.

but it isn't possible to downgrade reactors, is it?

[Tommygun]

Only by editing your craft information in the persistant file, but that's tricky.

Back up your persistant file if you try.

[sarbian]

Would you consider an half size version of the radial radiator ? The actual one is quite large for 0.65m satellite. I made myself one (half size, 1/4 surface) but I sure other may be interested.

[Umlüx]

true.

last question (for today ) i know you cant run two generators on one reactor, but how bout the other way around?

is it possible to sandwich a generator (small Nuclear Reactor - Generator - AM Reactor ) so i can run the base energy supply off the fission reacor and only activate the AM Reactor when i need power for the engine?

[Fractal_UK]

Hello!

TL:DR version:

1) Stock nuclear engines seem to be better than the ones in this mod until fusion power is researched. What's their use?

2) How do I obtain deuterium?

---Wall of text warning---

So I've been using this mod for some time and been enjoying it. Having worked through the tech tree in career mode in 0.7.4 I'm having some trouble finding useful applications for Nuclear-powered rockets.

Before fusion power, the thermal rocket configuration for a 1.25 nuclear reactor seems to provide less ISP and less thrust than a stock nuclear engine, at roughly the same weight, but with the added benefit of producing power. Using plasma thrusters increases the ISP but makes the thrust so low that performing interstellar manoeuvres becomes extremely time-consuming.

In short, the only useful application I've found for nuclear reactors is power generation for science labs. Thermal rocket thrust and ISP are too low to either land on the majority of planets or outperform stock nuclear engines.

I've just researched fusion power so this is about to change, but I'm wondering if anyone else has any ideas about using various sizes of nuclear reactors with different configurations of thermal nozzles/plasma thrusters? I've played around a bit but haven't found any configuration that seems to just... 'work'.

Finally, Engineer Redux seems to be having trouble determining delta-v with the vista engine, and I'm not sure how long the tritium/deut will last. I can breed tritium in the reactor but do I need to electrolyse for deuterium using the science lab or harvest with atmospheric scoops? It's going to be hard enough getting a 3.75m nuclear reactor powered vessel off of Kerbin without even thinking about landing it somewhere as well!

Thanks in advance - great mod with some challenging stuff in it.

The only advice I can give you on using the nuclear reactors + thermal rockets is to use LiquidFuel and use the biggest reactor possible. The reactors scale non-linearly in power output with size, all of the basic ones draw quite heavily on real nuclear reactor designs that were tested for space travel. The smallest is drawn from SAFE-400, a 400KW thermal, 100KW electric nuclear reactor that NASA is currently experimenting with. This one I have scaled up somewhat to try and make the smallest size a bit more useful.

At the top end, we go up to Phoebus-2, which I believe was the largest nuclear reactor ever built at just over 4GW_th and would have been used as an alternative Saturn V upper stage. This would've been a little larger in volume terms but only marginally heavier than the Aegletes-2.

Anyway, all of the nuclear reactors have better Isp than the stock versions at 915s compared to 800s for the stock nuclear engine but the thrusts start off very poor and become increasingly good as you go to the larger sizes.

You're therefore best off using the smallest reactor solely for power generation, the 1.25m for power generation and/or aircraft thermal jets and the two larger ones can do all that plus some spacecraft propulsion. Aegletes-2 is the one that is designed to be a really competitive spacecraft engine.

In 0.8, you can accentuate some of these advantages using Thorium reactors. Thorium is better suited large exploration type ships because it requires more reprocessing to remove neutron absorbing elements from the core but I have also discovered the working fluid can be higher temperature than Uranium, and that translates directly to better specific impulse.

Thorium will push your I_sp up to 993s and thrust up by ~27%. Aegletes 2 would therefore do, with LiquidFuel propellant, 849kN @ 993s I_sp, which pushes its TWR just ahead of the stock LV-N, in addition to the superior specific impulse.

Would you consider an half size version of the radial radiator ? The actual one is quite large for 0.65m satellite. I made myself one (half size, 1/4 surface) but I sure other may be interested.

Yes, you're probably right. Do you think that radiator has a place as it is and I should make a second, small version or do you think I should simply shrink the current part?

i am running with antimatter and have some collectors on the ship. but i don't think it is enough to prevent the tank from getting drained..

now this would be a nice new chart.. how many collectors do you need in each SOI to keep the tanks topped? i don't want to put half a dozen giant solarpanels on my ship to charge the tank..

Dr Nuke made these charts for every planet:

Charts

[sarbian]

Yes, you're probably right. Do you think that radiator has a place as it is and I should make a second, small version or do you think I should simply shrink the current part?

The current one has a place since the smallest deployable radiators are quite large (I made smaller version too but they look kind of ridiculous in smaller size). I have a use for the current size for larger 1m sat.

You should change the in-game name the current one to remove the "small" and add the small one.

[babbos]

sorry, wrong mod, ignore

Edited November 21, 2013 by babbos

[Fractal_UK]

The current one has a place since the smallest deployable radiators are quite large (I made smaller version too but they look kind of ridiculous in smaller size). I have a use for the current size for larger 1m sat.

You should change the in-game name the current one to remove the "small" and add the small one.

I'll have a look at making another scaled down version then, I think it should still offer plenty of cooling capacity for the smallest satellites.

Additionally, I'm about 1/3 of the way through the celestial body resource maps now but I have, at least, done the difficult ones (Eve, Kerbin and Laythe). Once the rest are done, the release shouldn't take long to finalise.

[Jivaii]

I installed 0.7.4 and have a few issues / remarks to make...

Time Delay

I love time delay! But really, now we are not able to land a probe remotely anywhere but Kerbin's moons right? Am i missing something?

Flight Computer

Issue 1, not precise Delta/v calculation. I think everyone must have noticed that by now, the delta/v burn command to the flight computer will not burn the amount expected by a node guide...

Issue 2, In a repetitive occurrence i could not make the Flight Computer to point straight. This happened on two identical very small probes that were attached to a main probe. Once detached and they were on their own, when i commanded them to point to Retrograde or the Node they would just spin out of control rolling like crazy. Unless i hit the time warp button fast enough, they'd spin so fast that i'd get the 'cannot warp while in acceleration' message, essentially rendering the game inoperable until a cancel command reached the vessel (~3m)...

Let me know if you'd like me to repost to GH

Mate, I think you're in the wrong thread. May I redirect you to Remote Tech 2?

[DrNuke]

i am running with antimatter and have some collectors on the ship. but i don't think it is enough to prevent the tank from getting drained..

now this would be a nice new chart.. how many collectors do you need in each SOI to keep the tanks topped? i don't want to put half a dozen giant solarpanels on my ship to charge the tank..

Fractal posted my chart earlier, just multiply the flux per the number of collectors to get your rate per second. Keep in mind those are the maximum amounts you can gather per planet, which means it's at the optimal altitude. Operating at different altitudes will yield reduced collections.

[mossman]

I just put a Science Lab in orbit with a large solar array but apparently it's not getting powered (And is therefore useless). Apparently this is because the stock "ElectricCharge" resource and that used by the mod aren't compatible. Why is this? Doesn't make sense to me that power produced from nuclear/antimatter reactors is any different in use then solar or otherwise.

[Jivaii]

I just put a Science Lab in orbit with a large solar array but apparently it's not getting powered (And is therefore useless). Apparently this is because the stock "ElectricCharge" resource and that used by the mod aren't compatible. Why is this? Doesn't make sense to me that power produced from nuclear/antimatter reactors is any different in use then solar or otherwise.

You need to supply the lab with Megajoules. Not just Electric Charge.

[Defesan]

I just put a Science Lab in orbit with a large solar array but apparently it's not getting powered (And is therefore useless). Apparently this is because the stock "ElectricCharge" resource and that used by the mod aren't compatible. Why is this? Doesn't make sense to me that power produced from nuclear/antimatter reactors is any different in use then solar or otherwise.

The science lab takes approximately 5 MW to operate, assuming you're only doing research or nuclear fuel reprocessing. In converted terms, each large solar panel, in Kerbin orbit, provides about 12 kW. I think. Probably around there somewhere. So in orbit around Kerbin, you'd need about 417 solar panels -- bear in mind we're talking the big ones here -- to power the science lab. It may seem unrealistic to have the two resources be incompatible, but really, there are only a few scenarios where they would even approach the same orders of magnitude. Are you flying your science lab in a very low orbit around the sun?