Question Brainstorm: How to build a spaceship?

[Kaito]

This leads to the obvious solution of using the propellant as liquid cooling for the electronics!

Thats perfect! As for maximum effect, dump it directly onto the electronics!

 

[JamesG]

I have. You haven't said exactly you're going to be doing all this insulation from cold, since (as T.Neo pointed out) a vacuum is already very insulating and doesn't conduct.

You also haven't explained why you think that having electronics fry themselves in their own generated heat is a good idea.

I was adressing the orginal concern over extreme cold conditions. My reply was he did not have to worry about that because the electronics would heat themselves. I never stated you did not need to cool anything. You jumped in out of context to the discussion at hand and assumed.

You know what assuming things makes you look like don't you?

 

[Andy44]

Actually, using propellant ot cool electronics is not so bad an idea, but it's not so practical. Many satellites use a heat pipe system which uses a fluid to carry heat from electronics heat sinks to external radiators. Heat is wierd in space, you'd think it's very cold, but without fluid to convect the heat away the inside of an unpressurized vehicle just stays hot, and the outer skin reflects heat back in.

This is the problem with spacecraft design, it seems so easy but years of experience tell us otherwise. Explorer I, the first US satellite, was supposed to be spin-stabilized. Works on paper, right? Just like a football pass? Nope. Turns out that energy dissipation from whip antennae and fuel slosh complicate the matter, and the vehicle tumbled end-over-end after a short time.

It's little things like this, that aren't obvious, that make it difficult for the backyard amateur to build his own space vehicle.

 

[T.Neo]

It's little things like this, that aren't obvious, that make it difficult for the backyard amateur to build his own space vehicle.

It's little things like that, which aren't obvious, that make it difficult for anyone to build anything.

 

[JamesG]

But in other environments they concequences for even small mistakes usually aren't so unforgiving.

Which Soyuz was it that the crew died because an air pressure release valve stuck open on their way down?

 

[Ghostrider]

But in other environments they concequences for even small mistakes usually aren't so unforgiving.

Which Soyuz was it that the crew died because an air pressure release valve stuck open on their way down?

Soyuz 11. BTW space is just a vacuum with some rads thrown in for good measure, it's far more forgiving than deep-sea diving where a hull breach would mean almost instant death and you're losing heat by the truckload. There are some industrial environment that can be far worse than space, the issue with space is the time needed to be rescued.

 

[Dig Gil]

In my latest post (before that let's strike out the balloon phase) I suppose that the engines are fired up before the reach extreme cold so, that way the reactions heat the engines themeselves.
Striking out the balloon phase makes us needing larger rockets which are more noticeable to the air traffic and military/government Radars :S .
To control temperature of electronics: I don't think that they will fry themeselves unless our construction is one of the worst efficiency-killing apparatus out there. In the launching and orbiting devices we would need to shield the electronics from solar radiation and strong magnetic fields, because it's that that makes temperature rising on space, but our main device, the robot (rover, probe, whatever you want to call it), has got its electronics in a Box with air inside that works like if it were a portable atmosphere. If the atmosphere becomes saturated with heat then we eject it to space and release into the Box more nitrogen from our liquid nitrogen canister. If there's too much cold we turn on the heating coils that then warm up this atmosphere ambient. When on the Moon the robot could also dissipate heat to the ground, couldn't it?

 

[Hielor]

I was adressing the orginal concern over extreme cold conditions.

Without actually ever mentioning where these "extreme cold" conditions actually are.

Since space is a vacuum, there's no particles to transfer your heat to (as there are in, say, Antarctica). The only heat loss is through radiation, which is a much slower procedure.

Electronics in space don't need to be insulated from cold the way they would in Antarctica, since they won't be losing heat anywhere near as rapidly. In fact, in spaceships, getting too cold is rarely the problem, it's usually the exact opposite: you have too much heat that you need to dump overboard. Thus, radiators.

Actually, using propellant ot cool electronics is not so bad an idea, but it's not so practical.

Hey, the SR71 used its fuel to cool the pilots!

 

[Sky Captain]

How to build a spaceship?

Hire the Top Gear team - they know how to build a space shuttle
http://www.orbiter-forum.com/showthread.php?p=138810&posted=1#post138810

 

[jedidia]

yeah, they might even get the thing to not crash and burn in a second attempt... :lol:

But reaching space with that contraption, or god forbid orbit, would require quite some design changes...

 

[Sky Captain]

Top Gear team + Mythbusters team together almost certainly could build something that goes really fast and high. Mythbusters has lot of experience in custom built equipment, electronics, remote control devices and various stuff that would be useful to guide the rocket. With help from some retaired NASA rocket engineers I think it`s plausible they could launch a small few kg sattellite into orbit.

 

[T.Neo]

Top Gear?

That was pretty much a publicity stunt, despite the huge cool factor.

I think, given the right resources, the Mythbusters team could definitely pull off something like a suborbital flight. They seem to be quite experienced in fabricating unusual devices, and (at least IMO) seem to have real ingenuity on their side.

 

[vonneuman]

and a lot of money:lol:

 

[Dig Gil]

That's the MAJOR problem.

 

[vonneuman]

That's the MAJOR problem.

Exactly. It all comes down to money