Transition from pressurised envoronment to vaccum environment

[MikeBH]

Hi Armin11, I like the plasma solution as I am a plasma physisist. But I am also a practical guy so I think you are right the airlock without any air is the best solution. You suggest a gel to replace the air. I think this should be a gel inside a flexible but impervious outer surface so like an inflated ballon. It does not really need to be gel. The astronaut makes his way through a surface between the two inflated ballons. The ballons are touching making a vacuum seal but the astronaut separates only part of the seal as he moves through. Because the surface touches the astronauts suit, no air escapes as she move through.

 

[armin11]

Hi Mike, I've thought about the inflatable structure outside the airlock, but I think the power used to depressurize the space between the balloons is much more than the airlock and the time to do that is so high.
Dear Ryan_m_b your comment put an idea to my mind. What if we don't make the gel stronger with the use of polymers instead we make it stronger with the help of magnetic field that keeps gel in place. Next stage is getting through this gel. You said if it gets dehydrated it turns into aerogel. So we keep the condition for the gel cold, so it won't get dehydrated at first. Once the astronaut gets into a pile of gel we vaporize the water at the back of astronaut so gel turns into aerogel and no air gets out, so astronaut can get out from the other side. when the mission is complete and astronaut wants to get back we insert water into aerogel or some other work to make the aerogel soft again so astronaut can get in easily. Isn't this possible?

 

[armin11]

Gels are made from polymers in water. You can make them stronger with higher densities of polymer, longer polymers and cross linked polymers. Problem is if you make it tough enough to withstand the atmosphere of the inside of the station an astronaut won't get through. Worse in space the water would just boil off and you'd be left with (at best) an aerogel.

What is your opinion about my previous comment?

 

[Ryan_m_b]

Dear Ryan_m_b your comment put an idea to my mind. What if we don't make the gel stronger with the use of polymers instead we make it stronger with the help of magnetic field that keeps gel in place.

I know of know mechanism by which this would work. You still aren't going to keep the water in place.

Next stage is getting through this gel. You said if it gets dehydrated it turns into aerogel. So we keep the condition for the gel cold, so it won't get dehydrated at first.

Temperature is not the problem, pressure is. Even if the gel freezes to ice that's not going to help.

Once the astronaut gets into a pile of gel we vaporize the water at the back of astronaut so gel turns into aerogel and no air gets out, so astronaut can get out from the other side. when the mission is complete and astronaut wants to get back we insert water into aerogel or some other work to make the aerogel soft again so astronaut can get in easily. Isn't this possible?

I'm not sure what you mean here. Aerogel is a porous solid, its the complete opposite of what you want as it would allow air through but not an astronaut.

 

[armin11]

I'm not sure what you mean here. Aerogel is a porous solid, its the complete opposite of what you want as it would allow air through but not an astronaut.

I understand that there are more than fifty different kinds of aerogels, so you are saying there is none of them that is not porous and is impervious?!

 

[Ryan_m_b]

I understand that there are more than fifty different kinds of aerogels, so you are saying there is none of them that is not porous and is impervious?!

An aerogel is a gel that has had it's water removed leaving just the frame. You possibly could make one non-porous by compressing it or adding some kind of coating but you might as well call that a composite material.

Either way how does making a non porous and impervious material help you with your problem?

 

[armin11]

Either way how does making a non porous and impervious material help you with your problem?

If when the astronaut gets into gel, we turn the back segment of the gel into aerogel,the segment which is in the airlock,then no air is lost!

 

[Ryan_m_b]

If when the astronaut gets into gel, we turn the back segment of the gel into aerogel,the segment which is in the airlock,then no air is lost!

So your proposed idea is:

1. A segment of the wall of the vehicle is made from non-pourous (i.e. air tight) aerogel
2. As an astronaut approaches this segment the side nearest to them becomes a gel
3. Pushing themselves forward the areogel in front turns to gel and the gel behind back to aerogel

Is this correct? Assuming it is here are my problems with each point

1. Can a non-pourous aerogel be built that is suitable material for the wall of a space vehicle?
2. I am unaware of any method of turning an aerogel back into a gel, especially in the manner described
3. Assuming you could do this when the outer aerogel is converted back into gel it is structually weakened and the water in it will boil away in the vacuum before freezing

Those are quick points off the top of my head but I'm fairly certain there are other, big problems with this proposal as well.

 

[Travis_King]

It's cheaper to waste the air. On big ships just have robots/vehicles to the work. Like the deep sea subs. If you need someone inside it fine, just drop on in, you have a tiny air lock between the vehicle door and the entry port, very little air wasted. If you do need to step outside, deal with the few cubic feet of air lost...

 

[armin11]

So your proposed idea is:

1. A segment of the wall of the vehicle is made from non-pourous (i.e. air tight) aerogel
2. As an astronaut approaches this segment the side nearest to them becomes a gel
3. Pushing themselves forward the areogel in front turns to gel and the gel behind back to aerogel

Is this correct? Assuming it is here are my problems with each point

1. 
   
   Yo got the idea right! Though it has many problems and flaws, I think it can be feasible!It is great idea for my course project! For turning gel into aerogel we use some CO2,is that right?

 

[armin11]

What about using hydrogel instead of gel?

 

[Ryan_m_b]

What about using hydrogel instead of gel?

Actually everything I've said has been with hydrogels in mind.

 

[aquinn@UB]

I don't know if anyone said this already , but You need a load lock of some kind that you can vent to isolate your vacuum " Chamber" or else you could never get the thing open.