heating and cooling a starship?

[Tyberius]

Subspace heatsinks are looking better and better.

"Don't like the physics in your universe, come to subspace! We'll let you get away with anything here!"

 

[Captain Robert April]

^Dumping the heat in subspace would certainly be a requirement for a stealth ship, like a Bird of Prey. For a ship with nothing to hide, I'm still leaning toward my deflector shield idea. It just seems less complicated, cheaper, and multipurposes an already established onboard system (at least as far as Star Trek ships go; for other shows and stories, YMMV).

 

[Crazy Eddie]

Everything you have just stated describes a closed loop feeding back on itself.

Neither the space shuttle nor the ISS have a multi-gigawatt fusion reactor on board capable of powering an advanced cooling system. Actually, both have power budgets in the tens of kilowatts, which makes such a system totally impractical.

A bigger generate just means more heat. which means you need a bigger generator which means more heat ad infinitum...

The generator isn't for getting rid of heat. The generator is for CONCENTRATING that heat so you can get useable work out of it again. The entropy level only builds once the primary generator is shut down and you're forced to try and run the cooling system off the heat you've already stored; since THAT loop is now closed, sooner or later you're going to have to add more energy to get the loop going again.

again, your power soruce is going to be adding to the heat you have to disipate.

No, you don't have to dissipate it. You have to CONCENTRATE it in a place where you can still extract useable work from it. The excess heat from the main generator adds to the heat sink as well, but with the advantage that it is producing energy from a fuel source and not from reclaimed energy of the heat sink itself. Thus the thermal loop remains an open system.

OK, I am beginning to see the disconnect here. What is your definition of a heat sink?

Generally speaking, a device that allows transfer of heat from one system to another. Usually, a heat sink will reach thermal equilibrium with the thing it's trying to cool, since the transfer is passive (i.e. the heat sink sits there like a sponge and soaks up excess entropy). If the heat is actively pumped into the heat sink, you can break equilibrium, so the heat sink can be much warmer than the ship itself.

yea, not a great example, but I was hoping you would understand that the entire pot is like the entire ship. You may be able to make variations in temperature in parts, but over all your temperature will increase do to the vacuum isolation.

Which is irrelevant. AVERAGE temperature may increase, but you only need to control the the temperature of part of it. Ordinary radiation from the hull would take care of the rest, not to mention impulse exhaust being dumped overboard at tens of kilograms per second (and this, too, makes a convenient heat sink if you can concentrate the ship's thermal energy in the exhaust plume; might even give you a few extra newtons of thrust).

Simple: you concentrate all of that heat to one corner of the pot and keep it there until you need it.

Here in lies the problem. You will collect more than you need.

That all depends on what you need it for, doesn't it? For a starship traveling in interstellar space light years from any other radiating body, I can think of a few things it might need that heat for.

how are the ship's power generators "outside" the system of the ship?

They're not. The FUEL, however, is. And strictly speaking, the cooling system and the ship's environment both constitute sub-systems within the larger system of the ship. And to again remind you that impulse exhaust constitutes an out-loop for the system, which makes the ship an OPEN system where fuel is fed in and exhaust is fed out. You can concentrate the heat anywhere you want within the overall system of the ship, you can convert it into useable work inside the ship or store it until you need it. But even if you don't use it to afterburn the impulse engines, since some energy is leaving the ship anyway, even having more heat than you can afford to store ceases to be a problem.

 

[Crazy Eddie]

^Dumping the heat in subspace would certainly be a requirement for a stealth ship, like a Bird of Prey. For a ship with nothing to hide, I'm still leaning toward my deflector shield idea. It just seems less complicated, cheaper, and multipurposes an already established onboard system (at least as far as Star Trek ships go; for other shows and stories, YMMV).

Especially since the deflectors are nearly always on, and only power up to HIGHER levels when something dangerous is going on.

 

[sojourner]

I have to concede based on the fact that we are debating "handwavium" vs known technology.

 

[Mytran]

Isn't "handwavium" one of the crucial components of a warp core, anyway?

 

[sojourner]

^It is the most versatile substance in the universe and can be found in anything from warp cores to coffee makers.

 

[Unicron]

Yep.