KSP Interstellar Extended Continued Development Thread

[EnigmaG]

2 hours ago, Liquid5n0w said:

Uranium needs a moderator to start a chain reaction, you can't just put a bunch of uranium together and get a reaction going, you need something to slow down the neutrons emitted.

Ok, is there a risen for the Uranium-Nitride-tank to by so heavy?

5 minutes ago, FreeThinker said:

Lithium need special storage requirments ? What would the mass fraction be? 

I do not know, i only know it dos not like (alkali metal) water and you can cut it with a knife. I do not know how it is handled industrial.

[Profit-]

Lithium is only stored in oil to prevent water from interacting with it as that can cause dangerous things to occur.   Without  water, it is like any other metal, except it is light like wood and melts at around 180c so it can be kept liquid fairly easily. 

[Liquid5n0w]

5 hours ago, FreeThinker said:

Lithium need special storage requirments ? What would the mass fraction be? 

Lithium would only need special storage if you are storing it in an oxygen environment because it quickly oxidizes.  For a rocket you make the fuel air tight anyways, so I suspect it would't need any special requirements.

But one question is that if it's solid how do you move it to the engine? As a powder?  Wouldn't that take up extra space over solid?

Edited June 22, 2016 by Liquid5n0w

[hirschhornsalz]

What about storing it heated? If you can store something at -200 °C in a cryostatic tank, you should easily be able to store something at +200°C where Lithium will be a liquid.

[Undecided]

EDIT: Nevermind, worked it out.

Edited June 23, 2016 by Undecided

[Liquid5n0w]

4 hours ago, hirschhornsalz said:

What about storing it heated? If you can store something at -200 °C in a cryostatic tank, you should easily be able to store something at +200°C where Lithium will be a liquid.

Yeah that is a good option, but I suspect that powder form would have less of a performance heat over insulation and heating.  Also you don't need much of it per second as plasma thrusters have a very low fuel flow.

[FreeThinker]

5 hours ago, Liquid5n0w said:

Yeah that is a good option, but I suspect that powder form would have less of a performance heat over insulation and heating.  Also you don't need much of it per second as plasma thrusters have a very low fuel flow.

Indeed, the power to transfer the Lithium is insignificant to the power required to propel it.

[VaporTrail]

On 6/22/2016 at 9:30 AM, Liquid5n0w said:

Uranium needs a moderator to start a chain reaction, you can't just put a bunch of uranium together and get a reaction going, you need something to slow down the neutrons emitted.

Actually, you can "just put a bunch of uranium together and get a reaction going," and it's actually a major part of nuclear weapon design, as opposed to reactor design (not that an understanding of it isn't necessary here).  The term is "critical mass". 

It really depends on your density of U-235 (or other fissile material). Get enough U-235 (or U-233, Pu-238, Pu-239, yadda, yadda...) close enough together and you will have a self sustaining nuclear fission chain reaction. Early (failed) designs for nuclear weapons used moderators, but almost all modern designs use nearly pure metallic uranium, plutonium, or some other fissile fuel. Depending on the type of weapon, the sub-critical mass of fissile material is turned into a super-critical mass (through rapid joining of two sub-critical masses, usually used in uranium bombs, or imploding a sub-critical mass into a high-density super-critical mass, used in plutonium bombs), allowing a (short-lived) sustained chain reaction. In short, bomb go boom.

A mass of lower grade uranium (approx 15% u-235, 85% u-238 or other non-fissile materials) has a bare-sphere critical mass well over 600 kg, while a bare sphere of weapons grade uranium (near 100% U-235) is critical at about 52 kg, or a diameter of 17cm. 

A neutron moderator allows a sub-critical mass the ability to go super-critical because it slows down those pesky fast neutrons to thermal neutrons, which are much more likely to be captured by the fissile material, and thus allow a sustained chain reaction. In a pressurized water reactor, water is used as a coolant, heat transport medium, and a neutron moderator, all at the same time. 

The thing about this critical mass is not that it goes boom. It just gets hot. Really, REALLY hot if the reaction goes on long enough. Hence the term "meltdown," which is basically when the reactor gets all gooey and delicious. A big worry in the early days was "China syndrome," where the molten reactor was supposedly able to tunnel to "China" (or at least to the water table) and become a big radiological hazard through a huge radioactive plume. Chernobyl was almost an example of this, because of the design of the reactor plant. The core was situated above a pump reservoir, that would have (had not three divers sacrificed their lives to manually operate valves to drain it) caused a steam explosion that would have worsened the already bad situation several-fold. 

Just one more thing. Every time someone uses the line "It's going critical!" in a film containing a nuclear reactor, a nuclear engineer laughs himself to (near)death. Just going critical isn't a problem. In fact, reactors go critical (and super-critical) all the time, as a part of normal operation. The degree, and control with which, a core goes super-critical is what matters. A (properly controlled) nuclear reactor generally goes super-critical relying on the one percent of neutrons that are released well after a fission event. These "delayed neutrons" (along with neutron-poisons in control rods, etc) are what allow the nuclear reaction to be controlled on a human time-scale. An uncontrolled power excursion in which the reaction is being sustained on the neutrons born directly from fission (produced in less than one shake, and yes, that IS a unit of time... from a fission event) is termed as a "prompt-criticality." The line between criticality and prompt-criticality is the dividing point between "reactor" and "bomb."

Please note, that it is pretty much impossible to turn a (properly designed) nuclear reactor into what most people would term a nuclear bomb without actually disassembling said reactor and reprocessing the materials. However, you can cause all kinds of unpleasantness by exploding a nuclear reactor pressure vessel. Just not "earth shattering kaboom" levels of unpleasantness. 

[FreeThinker]

Critical mass is actualy a major problem for long term nuclear power production in space. When storing nuclear fuel you need to make damn sure the fuel doesn't spontainiously start reacting. To prevent this, the fuel needs to be packed with neutron absorbing material that kill any runaway reactions. As a result, storing nuclear fuel requires a lot more mass than a regual rocket fuel. Therfore the mass fraction for Nuclear fuel storage is simply terrible. FUsion reactor don't have this problem. Therefore when in comes to long life durability, Fusion reactors will win despete the fact reactors themself are more complex and havier.

 

Edited June 24, 2016 by FreeThinker

[VaporTrail]

Not to mention that Deuterium/Tritium fusion has an theoretical energy density ten times that of fission on a strictly fuel related level.

[Aghanim]

Basically fusion reactors are the most OP energy source, as it is the most unlimited, clean, safe and powerful energy source, please nerf

Jokes aside, FreeThinker, can you please update CKAN installation to 1.1.3?

[Liquid5n0w]

8 hours ago, VaporTrail said:

Please note, that it is pretty much impossible to turn a (properly designed) nuclear reactor into what most people would term a nuclear bomb without actually disassembling said reactor and reprocessing the materials. However, you can cause all kinds of unpleasantness by exploding a nuclear reactor pressure vessel. Just not "earth shattering kaboom" levels of unpleasantness. 

What you can't just stick a rod of plutonium into a sub reactor and have it turn into a bomb with a 10 minute countdown?

I think you are overstating the mas fraction problem for uranium storage @FreeThinker.  Uranium is really really dense and you need a small amount of it to run a reactor, especially if it's highly enriched, which I assume would be the only think we would send to space because of the weight of the U-238 is basically dead weight for the payload.

[VaporTrail]

Nope. Worst case, you'd have the plutonium rod go critical in your hand from the neutron flux of the core (and you're dead anyway).  Best you could hope for is a fizzle yield that breaches containment... but that doesn't specifically require plutonium. 

I actually had a method worked out to break the reactor when I worked on one, which took a wrench, a screwdriver, a (specific) key, four to six uninterrupted hours, and a large rubber band (Swiss-Army Knife optional. This was fifteen years and two lifetimes ago... the equipment has changed since to prevent that method from working). It worked because I knew the safety measures built into the system, and actually used them to accomplish the goal. Granted, I'd never actually have tried it... but it was an interesting intellectual exercise. Hardest part was getting a hold of that key.

Definition of "a small amount" of uranium can still result in a fuel mass of tons and a huge volume. A PWR fuel assembly isn't just the fissile materials, it's the support structure, cladding, non-fissile uranium, control rods and mechanisms, and everything that makes the fuel assembly work. Even a pebble-bed design doesn't use straight uranium... the pebbles are mostly graphite wrapped around uranium dioxide, and not very dense at all compared to an equal volume of metallic uranium. 

You can't refuel a reactor like you would a car (well, maybe a PBR, but not a PWR). Pulling a PWR reactor core is a lot like an engine teardown/rebuild on an automobile... if you happen to be an automotively inclined weasel who's violently allergic to motor oil. The fuel rod assemblies have to come out as a piece, and go in as a piece, and coming out they're radioactive as all get-out coming out, and not really pleasant going in either.

Each fuel assembly has to come packaged in a transportation unit, that employs shielding (so the fuel in the new one doesn't  deplete, and the old one doesn't cause a mess). Refueling a CV(N) (two reactors) is an extended process that takes dozens of people months (at best) to accomplish. Granted, it takes on the order of two decades of run time to deplete the cores... so the trade-off is worth it. 

 

[Liquid5n0w]

13 minutes ago, VaporTrail said:

Definition of "a small amount" of uranium can still result in a fuel mass of tons and a huge volume. A PWR fuel assembly isn't just the fissile materials, it's the support structure, cladding, non-fissile uranium, control rods and mechanisms, and everything that makes the fuel assembly work. Even a pebble-bed design doesn't use straight uranium... the pebbles are mostly graphite wrapped around uranium dioxide, and not very dense at all compared to an equal volume of metallic uranium.

What is interesting is that no reactors are built where each and every gram matters.  I'm sure sub reactor designs are sensitive to weight, but not to the same extent that a reactor launched on a chemical rocket would be.  It's interesting to think about how light a reactor could be if you used only U235 and no safety equipment besides the crew shielding next to the reactor.

http://www.projectrho.com/public_html/rocket/basicdesign.php#fission

[VaporTrail]

Ok... still attempting the solar sat. Have a basic design that's working... ish. But something's not gelling... or several things.

Only thing different between the two is altitude above Kerbol. Sixty Gigantors @ 100% scaling. Radial out, transmitter on out facing end. Panels flat on to Kerbol, radiators edge on behind support arms). 

ElectricCharge capacity x 50 is Max microwave transmission, right? I'm getting a quarter GW transmitted, which seems right given energy flow on panels but... it goes down closer in? Sat is still at 800,000,000 m... but pushing only 205 MW and falling (~4 minutes game time from second pic). What am I missing?  

Thermal effects on my panels, but no waste heat in my radiators... I get much closer and the panels burn off (without a single tick of waste heat in the radiators). I know we're in the middle of a patch cycle, but I was having similar issues before the patch went live. Is something screwy actually going on, or is it in my head?

[FreeThinker]

19 minutes ago, VaporTrail said:

Ok... still attempting the solar sat. Have a basic design that's working... ish. But something's not gelling... or several things.

Only thing different between the two is altitude above Kerbol. Sixty Gigantors @ 100% scaling. Radial out, transmitter on out facing end. Panels flat on to Kerbol, radiators edge on behind support arms). 

ElectricCharge capacity x 50 is Max microwave transmission, right? I'm getting a quarter GW transmitted, which seems right given energy flow on panels but... it goes down closer in? Sat is still at 800,000,000 m... but pushing only 205 MW and falling (~4 minutes game time from second pic). What am I missing?  

Thermal effects on my panels, but no waste heat in my radiators... I get much closer and the panels burn off (without a single tick of waste heat in the radiators). I know we're in the middle of a patch cycle, but I was having similar issues before the patch went live. Is something screwy actually going on, or is it in my head?

I can't see what radiator you are using, but if you know, you could try to edit the radiator file and change isCoreRadiator to false.

[VaporTrail]

Graphite Radiator Folding Medium, x4, 100% scaling.

Believe it's out of Interstellar.

[Liquid5n0w]

8 minutes ago, FreeThinker said:

I can't see what radiator you are using, but if you know, you could try to edit the radiator file and change isCoreRadiator to false.

Either way, waste heat shouldn't affect how much power a solar panel makes right? It should only shut down the panel once it's too hot.

[FreeThinker]

20 minutes ago, Liquid5n0w said:

Either way, waste heat shouldn't affect how much power a solar panel makes right? It should only shut down the panel once it's too hot.

I don't know. after stock implemented star heating, I removed the old solar heat wasteheat mechanism. They were also kind of unbalanced as the operate on completely different power scales.

[Ericwi]

If you deactivate the nuke reactors on a solid core or CANDLE engine can you reactivate it?

 

[Liquid5n0w]

12 minutes ago, FreeThinker said:

I don't know. after stock implemented star heating, I removed the old solar heat wasteheat mechanism. They were also kind of unbalanced as the operate on completely different power scales.

But why is the solar output dropping when he hyperwarps the sat closer to the star?

[Nansuchao]

2 minutes ago, Liquid5n0w said:

But why is the solar output dropping when he hyperwarps the sat closer to the star?

Well, that has sense in reality, and it can be a stock feature, MAYBE.

[Profit-]

On 6/24/2016 at 4:57 AM, FreeThinker said:

Critical mass is actualy a major problem for long term nuclear power production in space. When storing nuclear fuel you need to make damn sure the fuel doesn't spontainiously start reacting. To prevent this, the fuel needs to be packed with neutron absorbing material that kill any runaway reactions. As a result, storing nuclear fuel requires a lot more mass than a regual rocket fuel. Therfore the mass fraction for Nuclear fuel storage is simply terrible. FUsion reactor don't have this problem. Therefore when in comes to long life durability, Fusion reactors will win despete the fact reactors themself are more complex and havier.

 

Just want to point out. Thorium, as it needs to be breed first, has NO critical mass and you can put a million tons of it in a lump. 

[Karpen]

Hey, I have a question. Sorry if it was already asked. I use the current KSPI version on 1.1.13, and the VASIMR Engine has always the "on" animation. Is there a way to turn this off and only seeing this when the engine is actually on?

[FreeThinker]

Version 1.9 for Kerbal Space Program 1.1.3

Released on 2016-06-26

• Compiled against KSP 1.1.3
• Replaced ORS Surface and Ocean resource gathering by Stock resource gathering system
• Molten Salt Reactor can now breed tritium using Lithium6
• Added harvesting of Alumina, Borate, Hydrates, Monazite, SolarWind, Uraninite. SaltWater, Silicates and Water to Stock Resource Drill
• Added ability to scan Alumina, Borate, Hydrates, Monazite, SolarWind, Uraninite. SaltWater, Silicates and Water with Orbital Scanner and
• Surface Scanner (disabled when SCANstat is installed)
• IRSU Refiniery now also accepts Electric Charge for imput
• Added HeavyWater Electrolysis to IRSU Refinery
• Added Borate Processing to IRSU Refinery
• Added Silicates Processing to IRSU Refinery
• Added SolarWind Processing to IRSU Refinery
• Added SaltWater Processing to IRSU Refinery