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Post by srbrant on Dec 2, 2017 3:06:20 GMT
I can imagine super-massive ships as mobile space colonies or cities, with just enough Delta-V to nudge its way in and out of a Lagrange point.
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Post by srbrant on Nov 27, 2017 5:16:01 GMT
What. A 10,000 sqm hull radiating at 500k disposes of less waste heat than a. 100 sqm radiator at 4000k. Orders of magnitude less. I don't see how a low temperature hull radiator is *at all* beneficial if you're using very high energy powerplants. Unless it's a non-Carnot powerplant like Fission Fragment. Good call. Then there's the issue of scale. I've always loved those enormous dreadnoughts and flying palaces you'd see in Star Trek or Warhammer 40,000. But are they practical? Useful? Efficient? How big can they get?
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Post by srbrant on Nov 24, 2017 16:34:49 GMT
srbrant : If you're going for a different technology level, why don't you just increase the efficiency of all your systems? Increasing efficiency can drastically reduce the amount of waste heat you deal with. This directly reduces the necessary radiator size. Another suggestion I have is gas-filled fins. I mentioned the possibility of 'gas-coolant radiators' in my All the Radiators post. The basic concept is that you fill a transparent bag with gas, then either deflate it once the gas has cooled down enough, or use a gas flow. The fins on your spaceships could be a similar design. Large transparent membranes with gaseous coolant flowing through them. They'd serve as radiators, but don't have to look like the typical flat metal panels of solid radiators. - That's exactly what I'm doing. I just want it to be fairly grounded in reality. Though to emphasize the futuristic setting, there's a whole rainbow of applied phlebetonium thanks to "Neo-alchemy", a new science born from advances in fusion power and exotic metallurgy. Sadly, all but a quarter of these miracle materials have had the secrets to their creation lost during the Technocaust. - There's an interesting idea. I shall consider using it.
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Post by srbrant on Nov 23, 2017 11:15:54 GMT
Well, now I know how science fiction writers in the fifties arrived to those brilliant ideas about nuclear campfires and nuclear washing machines. Gloss over enough details of controlling nuclear chain reactions and there is nothing you can't achieve. And atomic cars, which is probably the closest thing ISIS has to pornography.
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Post by srbrant on Nov 23, 2017 11:13:47 GMT
Good idea! Any ship designs you think would be the most plausible or efficient? Mostly cones and wedges, with radiators being either behind an armored bulge or edge on towards the enemy (providing a thin, hard to hit target). I'd expect combat spacecraft to be littered with sensors, cameras and antennas. Spacefleets/constellations might behave more like distributed webs of sensors and weapons then a naval fleet, since humans are only useful for decision making and armour is not cost-effective. That's why a lot of the ships that I've designed have that large hump - so that the radiators have something to hide behind. If that's not enough, each radiator has a protective cowl facing the front.
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Post by srbrant on Nov 23, 2017 10:21:11 GMT
Can the hull itself be used as a low-grade auxiliary radiator for the habitat module? Also, I've been thinking about fin-shaped radiators that can fold up like fans, though they'd likely need to be quite flexible in order to do so.
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Post by srbrant on Nov 23, 2017 10:02:44 GMT
That I still have to figure out, I'm sad to say. But I'll make a note of it to add more heat sinks. Especially for components that require very small sinks like drone launchers. Though I also had the idea of running coolant pipes through the hull so that the hull itself becomes a heatsink. Albeit one that won't be hot enough to glow. And while these advances in larger payload capacity means a much more spacious interior and significantly reduced added mass limit (like how much you can store on the ship), it's no cruise-ship. It's more like an apartment building at best. If you want non-electric projectile weapons with a higher muzzle velocity than conventional cannons, you might want to take a look at ram accelerators (maximum muzzle velocity of about 10 km/s). Light gas guns, electrothermal guns and blast wave accelerators make for decent projectile launchers too. Good idea! Any ship designs you think would be the most plausible or efficient?
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Post by srbrant on Nov 22, 2017 22:30:55 GMT
Kinetic weaponry is definitely used, though lasers and even exotic and esoteric weapons are employed as well. The reason many of the radiators look so small is because they're on particularly large ships (hypercoolants may be a factor as well.) The "top" and front armor is much more durable for head-on engagements, with the more sensitive equipment (observation domes, communication rigs, docking plugs, escape craft, etc) on the more lightly-armored "underbelly." Advancements in fuel efficiency, fusion engines, exotic metallurgy and supertensile solids means that ships are much larger and can carry significantly higher payloads. What ya mean with exotic and esoteric weaponry? You'll need a lot of heat sink to handle that much waste heat. Also if you use anything more advanced than chem and nuclear liquid and solid core engines you'll need very large radiators to keep your ship from turning into a molten slag. That I still have to figure out, I'm sad to say. But I'll make a note of it to add more heat sinks. Especially for components that require very small sinks like drone launchers. Though I also had the idea of running coolant pipes through the hull so that the hull itself becomes a heatsink. Albeit one that won't be hot enough to glow. And while these advances in larger payload capacity means a much more spacious interior and significantly reduced added mass limit (like how much you can store on the ship), it's no cruise-ship. It's more like an apartment building at best.
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Post by srbrant on Nov 22, 2017 17:47:45 GMT
0/10 no pusher plate for orions I don't believe in exploding nuclear turd propulsion. (XNTP)
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Post by srbrant on Nov 22, 2017 17:45:47 GMT
These look really good, they have a certain fantasy aspect to them. They would fit amazingly well in a soft sci-fi. Although having boring cylinders or other optimized forms aren't that pleasant to look at. And the fiction in science fiction has to be filled somehow. The radiators appear to be rather small, either you have very high outlet temperatures or use kinetic or missile weaponry. Laser as PDW and maybe even lightly armored sniper ships could work. Kinetic weaponry is definitely used, though lasers and even exotic and esoteric weapons are employed as well. The reason many of the radiators look so small is because they're on particularly large ships (hypercoolants may be a factor as well.) The "top" and front armor is much more durable for head-on engagements, with the more sensitive equipment (observation domes, communication rigs, docking plugs, escape craft, etc) on the more lightly-armored "underbelly." Advancements in fuel efficiency, fusion engines, exotic metallurgy and supertensile solids means that ships are much larger and can carry significantly higher payloads.
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Post by srbrant on Nov 22, 2017 6:26:54 GMT
Oh, and if you want more thrust you can always add in some remass Definitely.
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Post by srbrant on Nov 22, 2017 6:26:19 GMT
For ages, I've been trying to find the perfect starship design philosophies for my story - one that is the ideal balance between realistic and futuristic. I'm glad that I have you guys to turn to for more direct advice (though I feel embarrassed that I'm throwing out all these really speculative ideas like some hapless Trekkie), but I think it would help even more if you had a solid, tangible idea of my ships. Seeing how this is the only Hard SF space combat forum I know of. Here's a work-in-progress chart of Kemono Union ships, built using the "Foss-Gaughan" pattern of starship construction. As well as a somewhat helpful cutaway. Damn, I need a scanner so bad... Attachments:
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Post by srbrant on Nov 22, 2017 2:31:59 GMT
Thank the Omnissiah for fusion reactors... ...And the huge heat-sails in my story. The thing is, just use the damn fusion rockets you fik Okay, okay.
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Post by srbrant on Nov 22, 2017 2:21:47 GMT
Now I know for a fact that this is going to get shot down, but please hear me out. This is a possible way to increase velocity and RM efficiency. A miniature particle accelerator built between the fuel pump and the engine core that, like a coilgun, accelerates a minute portion of reaction mass until it is fired out the back end at three - perhaps even five - times the velocity. To prevent these pups from reaching relativistic speeds, their dry mass is increased until the Delta-V is at around 3-6.00. I know there's going to be a lot of shit being pointed out in this idea, but I want to see what the issues with it are and how I can seal them up with properly applied phlebetonium - enough so that the entire engine design isn't handwaved so I can prevent my SF from getting too soft. Besides engineering there's a physics issue. Engine thrust is (propellent mass) x (exhaust velocity) Engine power is (propellent mass) x .5 x (exhaust velocity) x (exhaust velocity) If you have 3x exhaust velocity (and thus 3x deltaV) the same thrust will require 9x as much power. 5x dV is 25x power at same thrust. Not impossible but there's going to be a lot of waste heat one way or another. Thank the Omnissiah for fusion reactors... ...And the huge heat-sails in my story.
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Post by srbrant on Nov 21, 2017 18:59:00 GMT
Using an particle accelerator won't be a practical mean of accelerating fuel, have you seen the LHC? That thing barely produces micronewtons and weight thousands of tons, extreme propulsion optimization could bring this a few magnitudes down but you still won't have "interesting" propulsion. Instead of using the accelerator to add high exhaust remass into the exhaust stream you could use it or something else to heat up fuel in the core. That would be useful all the way up to nuclear gas core designs. If you have something like fusion the accelerator could be used to initiate fusion reactions. I think you are trying to have innovative ideas in the wrong place, increasing "remass efficiency" can't be done without having to invest something, mass/energy and momentum are conserved in our reality, there is no way around this. But science provides a lot of options of having good fuel efficiency. Nuclear can be very good for within solar systems, even in stories if you have gas core nuclear thermal engines. Fusion is key to torchships, although not without adding remass such as tungsten to get high accelerations. Fusion power is incredibly commonplace in my story, so that's a yes. But how to make such a high-efficiency system without turning the ship into an 890Kt death machine?
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