I need a little bit of help with understanding some aspects of the
Stanford Torus design.
truly is worth a thousand words.
First, I'm assuming that I've drawn the Torus as the Stanford Study
described. If I've made an error, I'd appreciate anyone's
clarification.
Here are my questions.
1.) How does the rotating torus hull act as a pressure vessel when
it is bi-sected by a roof of glass? Won't atmospheric pressure blow
the two halves apart?
I know in pressure vessels here on earth, they try to avoid welds
wherever possible, instead rolling thick pieces of metal into
cyinders, spheres, and then making very difficult welds to join the
thick metal.
2.) Won't the non-rotating shell and chevrons entail a massive
reconstruction every time the habitat has to be moved into a
different orbit, or even if its orbit has to be adjusted with the
occasional boost?
3.) Mass is needed to provide radiation shielding. If the shielding
is attached to the habitat, the structure of the habitat has to be
upgraded to carry the load under centrifugal force. Wouldn't this
upgrading be primarily a matter of adding more structural support
(thicker pressure hull) thus reducing the amount of shielding
needed. Couldn't an attached shield encompass a thicker pressure
hull to carry the load of the shielding and then a cavity on the
outside of the pressure hull to stuff slag into. Wouldn't this
prevent complications inherent in moving the structure? Or is this
question a strawman I've put up to solve the problem I've posed in
question 2?
> 1.) How does the rotating torus hull act as a pressure vessel when
> it is bi-sected by a roof of glass? Won't atmospheric pressure blow
> the two halves apart?
>
> I know in pressure vessels here on earth, they try to avoid welds
> wherever possible, instead rolling thick pieces of metal into
> cyinders, spheres, and then making very difficult welds to join the
> thick metal.
>
out of place. As far as I remember, most of the pressure vessels here
are used to contain gaseous masses at tens of atmospheres, and so the
engineering requirements are much tougher than for spacecraft. A more
approximate comparison would be one using pressurized aircraft, were the
difference between internal and external pressure is roughly 1 bar -
like in space. And in that case, you can see that there are lots of welds.
Lucio Coelho
> (...)
> > 1.) How does the rotating torus hull act as a pressure vessel
when
> > it is bi-sected by a roof of glass? Won't atmospheric pressure
blow
> > the two halves apart?
> >
> > I know in pressure vessels here on earth, they try to avoid
welds
> > wherever possible, instead rolling thick pieces of metal into
> > cyinders, spheres, and then making very difficult welds to join
the
> > thick metal.
> >
> I think that the comparison with existing pressure vessels on
Earth is
> out of place. As far as I remember, most of the pressure vessels
here
> are used to contain gaseous masses at tens of atmospheres, and so
the
> engineering requirements are much tougher than for spacecraft. A
more
> approximate comparison would be one using pressurized aircraft,
were the
> difference between internal and external pressure is roughly 1
bar -
> like in space. And in that case, you can see that there are lots
of welds.
>
> (...)
> Lucio Coelho
bisected with a glass "roof" How's that going to work?
Welds are commonly used on large pressure vessels with
high pressures.
spherical pressure vessel is to cast two hemispheres and
weld them together.
Cylindrical pressure vessels need hemispherical ends
which are welded on to the cylindrical core.
======
As for the Stanford Torus, I believe the glass roof is
not a pressure carrying structure, it is unsealed and
presumably has vents in it to allow equalization of
pressure between the two sides.
Metallic pressure vessels are a lot easier to develop
than glass ones.
Disregard my previous comment about vented windows, I
misunderstood.
the metallic part will be difficult.
I envisage pre-loaded metallic load reinforcing rods
which pass through the glass and weld into the metallic
walls either side. Also, the window will have to be
hermetically sealed using gaskets, and tongue in groove
design. The window will probably be multi-layer, e.g.
I believe the Shuttle windows are 7 layers with air gaps
between.
Regards,
Cahrles R.
>Here are my questions.
>
>1.) How does the rotating torus hull act as a pressure vessel when
>it is bi-sected by a roof of glass? Won't atmospheric pressure blow
>the two halves apart?
>
Glass can carry tensile loadings- or else you can use ties across the
gap to keep the two sides from coming unzipped, and allow the air
pressure to help keep the glass pressed against the inside of the
habitat and maintain the airtight seal.
>wherever possible, instead rolling thick pieces of metal into
>cyinders, spheres, and then making very difficult welds to join the
>thick metal.
>
A technique called stir welding can be used, and gives excellent strength.
>2.) Won't the non-rotating shell and chevrons entail a massive
>reconstruction every time the habitat has to be moved into a
>different orbit, or even if its orbit has to be adjusted with the
>occasional boost?
>
I don't think it's too hard to move.
>3.) Mass is needed to provide radiation shielding. If the shielding
>is attached to the habitat, the structure of the habitat has to be
>upgraded to carry the load under centrifugal force. Wouldn't this
>upgrading be primarily a matter of adding more structural support
>(thicker pressure hull) thus reducing the amount of shielding
>needed.
>
Why don't you pull the figures from www.matweb.com and work out what you
need to do?
> Couldn't an attached shield encompass a thicker pressure
>hull to carry the load of the shielding and then a cavity on the
>outside of the pressure hull to stuff slag into. Wouldn't this
>prevent complications inherent in moving the structure? Or is this
>question a strawman I've put up to solve the problem I've posed in
>question 2?
>
You'd probably be better off having a non rotating shield that avoids
covering the windows.
I don't understand the reasons for confusion. Think of the Stanford Torus
shielding, "the shell" as the fender on a bicycle. The wheel (the torus,
people live where the air is) rotates, the fender does not. Jay Huebner
> I don't understand the reasons for confusion. Think of the Stanford Torus
> shielding, "the shell" as the fender on a bicycle. The wheel (the torus,
> people live where the air is) rotates, the fender does not. Jay Huebner
Of course spacecraft radiators are a bit more complex. In particular, they
generally need to transfer power and/or fluids across the rotary bearing.
These mechanisms are quite costly.
Hmm, I wonder if anybody has thought of using microwaves to transmit power
across rotating structures.