Global Flyer

In article ,
Ron Wanttaja wrote:

On Sun, 06 Mar 2005 23:33:48 -0500, Dan Nafe wrote:
[snip]
Doesn't the vehicle get lighter as fuel and oxidizer are consumed,
requiring less thrust, lowering the consumption rate...

Exactly, but the basic rocket equation takes that into account:

Fuel = Initial Mass * (1 - 1/(e^(Delta-V/(ISP * g)))

Ron Wanttaja

I guess that is why you are a rocket scientist.

Dan "Damn-it-Jim,-I'm-a-doctor" Nafe

Rich S. wrote:

P.S. I like that idea about recycling boomers!

They were hovercrafts in "The Matrix" or very close to it...

Ron Wanttaja wrote:
they powered Honolulu with
the output of *one* of these subs.

Cooling them in space, where you don't have access to billions of tons of cold
sea water, is left to the good offices of your local thermal engineer.

Ron Wanttaja

Help me out with this one. While all the sci-fi I sopped up as a kid
referred to the "cold of outer space," isn't vacuum a perfect insulator?
How WOULD you cool the reactors (or whatever engine) with no atmosphere
or handy heavy liquid at lower temp? Wouldn't it take a long time for
the excited molecules to settle down?

I love this thread.

StellaStarr wrote:

Ron Wanttaja wrote:
they powered Honolulu with
the output of *one* of these subs.

Cooling them in space, where you don't have access to billions of tons of
cold sea water, is left to the good offices of your local thermal
engineer.

Ron Wanttaja

Help me out with this one. While all the sci-fi I sopped up as a kid
referred to the "cold of outer space," isn't vacuum a perfect insulator?
How WOULD you cool the reactors (or whatever engine) with no atmosphere
or handy heavy liquid at lower temp? Wouldn't it take a long time for
the excited molecules to settle down?

I love this thread.
Yea I already have my moon station built and the prefab's ready to ship,
life supports finished now all I need is to complete the rockets to get
them there! As soon as I'm finish with the KR-2 ( at current rate that will
take another 30 years!).
John
wishin and dreamin

On Thu, 10 Mar 2005 03:05:16 GMT, StellaStarr wrote:

Ron Wanttaja wrote:
they powered Honolulu with
the output of *one* of these subs.

Cooling them in space, where you don't have access to billions of tons of cold
sea water, is left to the good offices of your local thermal engineer.


Help me out with this one. While all the sci-fi I sopped up as a kid
referred to the "cold of outer space," isn't vacuum a perfect insulator?
How WOULD you cool the reactors (or whatever engine) with no atmosphere
or handy heavy liquid at lower temp? Wouldn't it take a long time for
the excited molecules to settle down?

Yes, it would. The vacuum of space is an excellent insulator, but there's a lot
of "nothing" to suck your heat away. Operational spacecraft usually have
problems with TOO much heat, but if stuff shuts down, things get cold. If the
Space Shuttle doesn't get the doors open soon after orbital insertion, it has to
land, fast...the spacecraft's radiators are on the inside of the doors. On the
flip side, remember the movie, with the power-conserving astronauts freezing.

You get rid of heat with, basically, radiators. Point 'em at black space and
that's about the best you can do.

Cooling a submarine reactor in space is going to be difficult, since IIRC
correctly the reactor is basically a heat source for the creation of steam,
which then turns the turbines that rotates the screws or spins the generators.

You might end up with a big external radiator, kind of like a conventional solar
array only you keep it turned FROM the sun. I don't like this solution, as a
leak is not only going to spew your precious coolant into space, but act as a
thruster upsetting your attitude.

I kind of like the thought of "rafting" three sub hulls side-by side, with the
two outer ones lacking a reactor but stringing radiator tubes on the inside of
the hulls. You might even run radiator lines all through the hulls, then fill
the whole hull with water and freeze them before launch. But like I said, I
ain't a thermal engineer.

Ron Wanttaja

On Thu, 10 Mar 2005 04:12:09 GMT, I wrote:

Yes, it would. The vacuum of space is an excellent insulator, but there's a lot
of "nothing" to suck your heat away. Operational spacecraft usually have
problems with TOO much heat, but if stuff shuts down, things get cold. If the
Space Shuttle doesn't get the doors open soon after orbital insertion, it has to
land, fast...the spacecraft's radiators are on the inside of the doors. On the
flip side, remember the movie, with the power-conserving astronauts freezing.

Agghhh, I was a bit rushed and edited this wrong. Insert "Apollo 13" after
"...remember the movie,".

Ron Wanttaja

Ron Wanttaja wrote:
snip
I don't like this solution, as a
leak is not only going to spew your precious coolant into space, but act as a
thruster upsetting your attitude.


Ron Wanttaja
snip

If we're going to take along precious coolant I vote for Newcastle Brown
Ale ;^) And if you lose it there will be an upset attitude G

"Blueskies" wrote in message
. com...

Big bouncy spring thing hopping between the craters...

At first I laughed - but now that Ron has 'splained things to me, you might
have been right after all!

Rich "If you have to have something to push against, why not the Moon?" S.

"Gary Thomas" wrote in message
...
If we're going to take along precious coolant I vote for Newcastle Brown
Ale ;^) And if you lose it there will be an upset attitude G

Hmmm...... What would be the thrust numbers (ft/sec) for Muzzleloader, I
wonder? What would you carry as an oxidizer? Can it be synthesized from
locally available materials?

Chuck - could you run some experiments with an Earth-bound
Muzzleloader-propelled ultralight and give us some numbers?

Rich S.

"Rich S." wrote

Hmmm...... What would be the thrust numbers (ft/sec) for Muzzleloader, I
wonder? What would you carry as an oxidizer? Can it be synthesized from
locally available materials?

Yep, I know of the perfect oxidizer. Grind up a bit of BoB U, and combine
them, for the perfect result. From what I hear, they do burn out rather
quickly, but *can* be revived to burn again. Bfg
--
Jim in NC