Re: [PSUBS-MAILIST] Close cycle gasoline engines

[Ian Roxborough <irox@ix.netcom.com>]

On Fri, 30 Aug 2002 16:09:22 +0200
melon <melon@online.no> wrote:

> I intend to (attempt to) run my sub with a crossbreed of a hydrogen peroxide 
> (h2o2) turbine, and a stirling engine/hydrogen fuel cell system.

There is already a hydrogen fuel cell system using hydrogen peroxide,
they are probably a few now.  The one I remember had the H2O2 stored
inside of ping-pong balls which would be cut open when more fuel
was needed.

> The rough theory is as follows, hydrogen peroxide is a fairly stable liquid.  
> It turns into a gas when it comes into contact with a number of things 
> (silver, copper), something the designers of "Kursk" found out.

I think you'll find that this was well know long before the "Kursk"
was even designed.

>  The  transition from liquid to gas gives you a fair bit of energy to feed
> a normal  gas turbine, and also gives you heat, to run a stirling engine.

H2O2 contains soooooooooo much energy that you don't have to
worry about effiently extracting all the energy.  If you're 
serious about working with H2O2, then I'd pick one method
of extracting energy and stick with it.  The is no need to
extract all the kinetic, thermal and chemical energy stored
in H2O2. 

Combining all three methods will probably just tripple the
amount of problems you've got solve.  I would suggest dropping
the turbine part altogether.  Blades chopping through a mixure
of super hot gas made from H2 and O2 seems really dangerous.

> Coincidentally, the process gives you hydrogen and oxygen, to feed your fuel 
> cell, your air scrubbing system etc.
> 
> It's a match made in heaven, although some would argue a match that requires
> a lot of piping, tanks, valves and possibly too much mumbo jumbo to be of

(Valves and piping might be too dangerous since H2O2 is pressure
 sensitive.)

> real value. But then again, I am not building a sub because it's the easiest
> thing to do.

H2O2 does seem like the prefect match to for the submarine 
endurance problem (energy + breathing gas).   Of course I've
not yet seen a personal submarine that really needs this problem
solved (OK maybe CSSX1).

Remember the designers of "kursk" had 40 or 50 years head start
over any psub'ers.

As for the safety aspect, for some people anything is dangerous,
but if you come up with a complete test plan, where most of the
testing is done remotely, with nobody in 100+ feet (or whatever
safe radius is need).  With much testing on dry land before
more remote controlled wet trails.  Plus destructively testing
a few designs so that you can understand how they will fail and
place armour between the H2O2 unit and human storage vessel.
Also maybe conducted unmanned tests where set off a failure
in a finished submergerd submarine to see if the pressure vessel
will survive.  This will all cost big bucks I'd imagine, but so
would a submarine that would need such a device.

I know some people on the list would rather not discuss H2O2,
but AIP this is one of favourite topics.  Although personally
I think I'll be trying something more a long the lines of
converting a K350 to be an underwater glider for my AIP project.

Ian.


-- 
The moon ate the sun on Monday and it was an awsome sight to see.