Waste Heat and Cooling

[Starglider]

This is a relevant question for a simulation I'm working on - over long bombardments, ISD armour thermal conductivity is (presumably) good enough that the temperature of the whole outer hull will reach hundreds of degrees, causing further impacts to do more damage and ultimately large areas of the hull to melt, unless there is an extremely powerful active cooling system to prevent this. Clearly waste heat issues for heavy turbolasers, much less the superlaser, would be insurmountable without either incredible efficiencies or incredible cooling, but even an X-wing would have serious overheating problems with contemporary efficiencies and cooling tech (and no visible large radiators). Possible options for ultratech cooling are pumping heat into ultradense or extradimensional heat sinks (including possibly fuel reserves), dumping it out the engine exhausts somehow, using the shields as a radiator (though we don't see red-hot glowing shield surfaces) or internal buried radiators using neutrinos, tachyons or some other sort of non-interacting particle.

[Xess]

The ROTS:ICS shows shield generators attached to neutrino radiators so I'd say that they use similar technology for disposing of waste heat generated by weapons.

[Starglider]

The ROTS:ICS shows shield generators attached to neutrino radiators so I'd say that they use similar technology for disposing of waste heat generated by weapons.

Thanks: I don't have the book, but that would be my preference anyway. Ultratech cooling adds another soft-sci-fi gadget, but the setting has plenty of those already. Once you've got that it can be used to support any other high-energy-intensity technology. Requiring incredibly high efficiencies for everything energy intensive is a locally low but pervasive strain on credibility that adds up to a worse hypothesis, IMHO.

Amusingly just assuming still-very-high 99.9% reactor-to-muzzle efficiencies on all heavy weapons is going to add enough active cooling to an ISD to considerably (further) raise the number of GCS required to take one out.

[Sarevok]

The ROTS:ICS shows shield generators attached to neutrino radiators so I'd say that they use similar technology for disposing of waste heat generated by weapons.

Ok total physics lay person here.

When a ISDs HTLs are firing there could be a huge number of neutrinos flooding the ship. Dont neutrinos cause very tiny effects which allow them to be detected here on Earth ? At close proximity to a ISD's extremely powerful reactors would it have any effects on the crew's health ?

[SCRawl]

The ROTS:ICS shows shield generators attached to neutrino radiators so I'd say that they use similar technology for disposing of waste heat generated by weapons.

Ok total physics lay person here.

When a ISDs HTLs are firing there could be a huge number of neutrinos flooding the ship. Dont neutrinos cause very tiny effects which allow them to be detected here on Earth ? At close proximity to a ISD's extremely powerful reactors would it have any effects on the crew's health ?

Neutrinos don't interact with very much at all. I can recall one of my physics professors quipping that they have a mean path length -- the average distance a neutrino will travel before interacting with its medium -- of a light year in lead. He might have been exaggerating, but the fact of the matter is that neutrinos pass through stuff very well, and if it passes right through you without hitting anything, it's not going to harm you.

If you have uncountable quintillions being generated each second, though, the odds that one will eventually interact with one of the cells in your body (and mutate it, possibly causing cancer) goes up. It's just really small to start with.

[Wyrm]

I once calculated that a neutrino dose density of 3.56e30 neutrinos/cm^2 at ~20 MeV should deliver a radiation dose of around 227 grays (Gy), and assuming a 3rd of these result in charged current interactions, should be a dose of 75.66 sieverts (Sv), which is enough radiation for disorientation to set in within minutes from CNS syndrome, and almost certain death resulting.

Basically, it's the neutrino dose taken 1 AU from a SN 1987 A supernova event. Of course, your goose would be quite thoroughly cooked for other reasons.

[Starglider]

Truly vast quantities of neutrinos will cause enough ionisation to be a problem, but if the radiators are unidirectional and positioned to radiate out through the hull the crew won't have a problem (though if this is the case you might not want to park your ISD in front of the Death Star's radiators).

[Warsie]

over long bombardments, ISD armour thermal conductivity is (presumably) good enough that the temperature of the whole outer hull will reach hundreds of degrees, causing further impacts to do more damage and ultimately large areas of the hull to melt, unless there is an extremely powerful active cooling system to prevent this.

Not really, based on the X-wing novels ISD armor can be vaporized by one turbolaser hit

Clearly waste heat issues for heavy turbolasers, much less the superlaser, would be insurmountable

Turbolasers use coolant fluid which is supposedly dangerous and the Superlaser is in a tube some distance wide to keep the laser from interacting with anything/

but even an X-wing would have serious overheating problems with contemporary efficiencies and cooling tech (and no visible large radiators).

IIRC, isn't that why the X-wings lock their S-foils in attack position, for more surface area to cool off due to the fact that they will be creating more heat from the lasers and such?

Not so sure, please don't flame me.

But for planetary shield systems, they absorb the energy and bury it into the planet

[Starglider]

over long bombardments, ISD armour thermal conductivity is (presumably) good enough that the temperature of the whole outer hull will reach hundreds of degrees

Not really, based on the X-wing novels ISD armor can be vaporized by one turbolaser hit

Actually I was referring to an ISD versus horde of GCS simulation I've been working up - Federation phasers are sufficiently low powered that slow cooking is a serious issue.

[Batman]

Assuming naval phasers on full power have a noticeable thermal component to begin with. Do they? I honestly don't know, and the scorching they do on Trek ships seems to suggest they do, but on the other hand if it WAS direct heat transfer shouldn't we see melting/vaporization and noticeable thermal side effects? Whenever phasers actually leave holes in ships it appears to be NDF damage (or so memory says).

[Starglider]

Assuming naval phasers on full power have a noticeable thermal component to begin with. Do they?

Sometimes. The glowing edges, melting, scorching and vaporisation are quite apparent when the Reliant is blasting the Enterprise in 'The Wrath of Khan'. OTOH in 'Generations' the disruptor bolts didn't seem to be doing much to the Ent-D other than leaving scorch marks and cracking coolant pipes (the later seems to be what actually destroyed the ship).

Whenever phasers actually leave holes in ships it appears to be NDF damage (or so memory says).

Unfortunately these 'NDF effects' are so wildly inconsistent in the show it's very difficult to come up with a convincing empirical model for them (in fact it's rather amusing to watch the authors of TNG tech manual try to do so - Mike Wong's page limits itself to speculation about the general mechanism and qualitative limitations). I'm just assuming that ISD hulls are at least as resistant to phasers as TNG packing crates, and thus only the raw (thermal) energy input has to be calculated. I am however generously assuming (in the default params for that sim) that phasers have the same apparent damage multiplier against Wars shields that they seem to have against Trek shields, simply because it's a '(sensible) upper limits of Trek versus lower limits of Wars' comparison.

[Warsie]

Actually I was referring to an ISD versus horde of GCS simulation I've been working up - Federation phasers are sufficiently low powered that slow cooking is a serious issue.

Okay, sorry

[Wyrm]

IIRC, isn't that why the X-wings lock their S-foils in attack position, for more surface area to cool off due to the fact that they will be creating more heat from the lasers and such?

When the S-foils spread, the corresponding points in the wing forms two new surfaces. The effective area of any radiators in the wings increases by the area of these two surfaces. This is because the opposing wing is blocking the heat radiated from the undersurface, and will reabsorb any heat that hits them. (Good radiators are also good absorbers.)

[bz249]

[quote="Sarevok"][quote="Xess"]The ROTS:ICS shows shield generators attached to neutrino radiators so I'd say that they use similar technology for disposing of waste heat generated by weapons.[/quote]

Ok total physics lay person here.

When a ISDs HTLs are firing there could be a huge number of neutrinos flooding the ship. Dont neutrinos cause very tiny effects which allow them to be detected here on Earth ? At close proximity to a ISD's extremely powerful reactors would it have any effects on the crew's health ?[/quote]

This is the site of the Sudbury Neutrino Observatory http://www.sno.phy.queensu.ca/ just check the quantities of heavy water and the detected neutrino flux. So nothing to really worry about.
The only possible issue with this system is the conservation of the leptonic charge (but this can be easily eliminated if they radiate neutrino-antineutrino pairs).

[Cykeisme]

IIRC, isn't that why the X-wings lock their S-foils in attack position, for more surface area to cool off due to the fact that they will be creating more heat from the lasers and such?

When the S-foils spread, the corresponding points in the wing forms two new surfaces. The effective area of any radiators in the wings increases by the area of these two surfaces. This is because the opposing wing is blocking the heat radiated from the undersurface, and will reabsorb any heat that hits them. (Good radiators are also good absorbers.)

True, the opposing S-foil would "shadow" and absorb a lot of the radiation from the inside-facing surface, but this is a three-dimensional situation. For any given point on the inside surfaces, a significant portion of the radiated heat would "miss" the opposite S-foil.

Still, I doubt this is the only (or even primary) reason for S-foil separation, otherwise they'd separate further (even a full 90 degrees) to avoid the problem mentioned before. It may simply be to spread out maneuvering jets that are arrayed along the edges of each foil.

[Wyrm]

True, the opposing S-foil would "shadow" and absorb a lot of the radiation from the inside-facing surface, but this is a three-dimensional situation. For any given point on the inside surfaces, a significant portion of the radiated heat would "miss" the opposite S-foil.

Exactly. In order to provide cooling (rather than just playing hot potato with its twin), the heat radiated has to escape to space. For the heat in the new volume formed by the two S-foils to escape to space, it must to go through the surface of that volume. Therefore, the extra cooling provided by the radiators in locked position is dependent on the area bounding that volume.

Still, I doubt this is the only (or even primary) reason for S-foil separation, otherwise they'd separate further (even a full 90 degrees) to avoid the problem mentioned before. It may simply be to spread out maneuvering jets that are arrayed along the edges of each foil.

This is my thought, too. The spread S-foils would get a larger lever arm on the pitch (and sacrafice a little lever arm on the yaw).

[Warsie]

When the S-foils spread, the corresponding points in the wing forms two new surfaces. The effective area of any radiators in the wings increases by the area of these two surfaces. This is because the opposing wing is blocking the heat radiated from the undersurface, and will reabsorb any heat that hits them. (Good radiators are also good absorbers.)

Right.

[Illuminatus Primus]

The ROTS:ICS shows shield generators attached to neutrino radiators so I'd say that they use similar technology for disposing of waste heat generated by weapons.

Ok total physics lay person here.

When a ISDs HTLs are firing there could be a huge number of neutrinos flooding the ship. Dont neutrinos cause very tiny effects which allow them to be detected here on Earth ? At close proximity to a ISD's extremely powerful reactors would it have any effects on the crew's health ?

This is the site of the Sudbury Neutrino Observatory http://www.sno.phy.queensu.ca/ just check the quantities of heavy water and the detected neutrino flux. So nothing to really worry about.
The only possible issue with this system is the conservation of the leptonic charge (but this can be easily eliminated if they radiate neutrino-antineutrino pairs).

Maybe sterile neutrinos exist in SW, and they're radiated by these radiators. In which case they don't even interact with the weak force.