sub build underway christmas 2011

A submersible shell which copied the engineering present in known structures.

There is no indication of how the engineering in dissimilar structures translates- therefore no way of determining how his work will respond to loads imposed in use.

Further- failed to demonstrate that a poured concrete submarine build is within the reasonable capabilities of the home builder.
A submersible shell built in Columbia, proves to the contrary that the build method may have significant insurmountable challenges.
This build is visibly showing cracking, voids, discontinuous pour used to lay up.

Further as far as a visionary he is illogically and oddly focusing on the single feature of hull material as having a profound effect on the viability of ocean cruising on submersibles.
He spares no words in describing the panacea of ocean cruising from his short experience of sitting in a lake in a underpowered shell he built.

For instance he goes at great length to say that the submersible is 'immune' to storms at sea from having sat through a single thunderstorm in a lake in his underpowered shell.

His vision fails to address how a real submersible operating at sea can submerge to sufficient depth for sufficient duration to be of any use as a storm tactic.
He gives absolutely no indication of how he might maintain trim or power through these storms he says he is safe from, and has no experience from which to speak.


I would not travel at sea in a semi submersible if someone gave one to me.
Have you been to sea Tugboat?
Have you seen how much shipping is out there?

Being run down is a simply assailable risk to what remains a untried and hypothetical endeavor.

He is if nothing else- enthusiastic.
A visionary?

Follow his vision at your peril.

Genius?
This vision has been around for what?
A hundred years or more?

http://en.wikipedia.org/wiki/Twenty_Thousand_Leagues_Under_the_Sea

 

It has nothing at all to do with the "rapid expansion of gases".

The drum collapses because the gas inside it (in this case the atmosphere) has been largely driven out of the oil drum and replaced with water vapour.

The implosion is due to atmospheric air pressure acting on the drum when there is a partial vacuum inside, with that partially vacuum being caused by the phase change of water vapour back to water liquid.

It illustrates that a vessel that will hold a significant internal pressure (oil drums are typically OK for 1.5 to 2 bar above atmospheric I believe, they have to be to take the internal forces from high density liquids) can easily fail at a lower differential pressure when the direction of the force is reversed.

The failure mode is typically Euler buckling, and is worth looking into, even if you don't want to do any math................

 

Still waiting for drawings to study and comment on. It's not my job to prove anything right or wrong. The sea does that just fine. This is absolute BS. Poster is just looking for a fight.

 

he has done it--ive talked to him..he did have working prototypes prior..he has good reasons not to divulge things- i agree with his reasoning--i dont necessarily agree with everything he says--we differ on the hull shell such as the quasi-ferr-cement hull that i proposed vs his thickl concrete hull... we differ on some of the ways to surface and run submerged and the weights and the shape of the hull..but he still-in my opinion -is a leader in that he had the guts to try- fail or succeed the guys a leader and a visionary to use concrete..its not been done other than by him that i know of-and only a matter of time before this type of hull is made to work...--this make him unique.like it or not -agree or not with his engineering--he has gone where no one else dared...
by the way those voids are a non issue-nothing an epoxy cement wouldnt fix..its really a no issue there...the pressure in fact does seal up the hull-it compresses it until there is no more spaces to be opened..look at the trieste it leaked on the surface but the pressure closed it up...

 

no --not looking for a fight--I WAS LOOKING FOR A HATCH!!!..thats it-thats all-i DO NOT need to prove or justify anything to you or anyone else- take it or leave it- i know what i know and -im quite content listening to you guys argue over it...


bottom line --if you don't like my posts-or this thread --you know where the door is... go somewhere else and complain ...better yet if you know so much--help me with my tug build...

 

yes the rapid expansion of gases then the cooling - causes the vacuum--we are talking the same thing-Jeremy take the heating and cooling out of the equation --can the buckling occur?? btw its only capable of withstanding 1 atm...nothing more...exaclty 1 atm. thats the vaccum-

 

I am sorry to burst your bubble Tugboat- he is proceeded by and copies decades of work done by others including fully build and functional concrete submarines.

Is anyone a "visionary" by copying the work of others.. build in steel, build in concrete.
What difference does it really make?- you still just have a hull.
The real challenges lie in the systems build out and the utility of cruising the submersible.

This thread is going nowhere as it perhaps has nowhere to go-
Wellmer provides no example to follow.
To the degree that interest lies in pursuing concrete as a hull material, I suppose the 'other thread' will sus out the topic.

I am still interested in your answer to my question:

And to answer your question above- no: a oil drum is not capable of withstanding 1 ATM

 

Sorry, but you're still talking about gases here. The drum collapses because there is very little gas (i.e air) inside it. The air has been forced out, leaving virtually no gas inside the drum at all. It doesn't then collapse specifically because it's been cooled, that's just the mechanism by which the phase change is induced which removes the water vapour and causes the partial vacuum (which won't be "exactly 1 atmosphere", BTW, it will be limited by the effectiveness of the removal of air by the water vapour and by the partial pressure of water vapour - some of the vapour will remain as the pressure reduces).

 

Is anyone here familiar with the term "Beating a dead horse"?

-Tom

 

The TRIESTE is an underwater Dirigible with a heavy personnel sphere hanging from a steel envelope full of lighter-than-water gasoline. The envelope is light and the petrol non-compressible. How does this correlate with the concrete sub? I don't get the connection other than they go under water.
The oil drum failing in compression is obvious. The thin steel of the drum is intended to be loaded in tension by its' internal contents.
By evacuating the interior by any means, boiling or a vacuum pump, it inevitably fails in compression before 1 atm pressure difference.

 

People are nutty and unfailingly bright.

That TRIESTE ship really captures the imagination by sailing the depths like a hot air balloon

 

"I am sorry to burst your bubble Tugboat- he is proceeded by and copies decades of work done by others including fully build and functional concrete submarines."


***** then you admit the concept works?...so now the question is how to integrate the systems


Is anyone a "visionary" by copying the work of others.. build in steel, build in concrete.
What difference does it really make?- you still just have a hull.
The real challenges lie in the systems build out and the utility of cruising the submersible.
**** yes
This thread is going nowhere as it perhaps has nowhere to go-
Wellmer provides no example to follow.
To the degree that interest lies in pursuing concrete as a hull material, I suppose the 'other thread' will sus out the topic.

I am still interested in your answer to my question:

You build using the designs you mentioned above...using working hulls and based on the empirical tests done by labs- by me using hydraulic presses..using say 2 inch thick ferr cement-reading on how to reinforce the mateials- and then over build it again...just to be sure...


And to answer your question above- no: a oil drum is not capable of withstanding 1 ATM

OK YES-- I believe that any cyclinder unless re-inforced will only withstand exaclty 1 atm..or the air removed from any closed cyl..is 1atm before buckling failure-

http://www.youtube.com/watch?v=8D2Q-UawaeA&feature=g-user-u

 

the trieste had a sphere and the data is conctradictory-some say 1 inch thick others 4...never the less there were leaks that were sealed under the pressure...btw see carl t fross's youtube channel he is an expert-and sorry it was exactly 1 atm

 

guys- dont ask me to provide evidence--you need to provide evidence it WONT work!--im tired here..im off to my tug build--if you agree with this thread stay... if not -no one is forcing you to stay and debate--if you are all so much expert engineers-dont you have better projects to be thinking about? i am sure your time is better spent elsewhere...

please feel free to help with my tug build i have lots of questions and know less about the initial set up than i do about amateur sub designs..so ill see you around. ive already pointed out I am not building the sub for a long time if ever so it moot anyway!!

why do we need to repeat over and over your points and my points?? i am not going to prove what i know to you- no one can--if your right then whatever- but the tug build is my priority--and none of you have built a sub anymore than i have, and have the same knowedge as i do and can access the same knowedge--so its time to let it ride...ill let you ramble on now..thanks for the input ill take the good and throw out the crap...im interested in a boat...because of the reasons mentioned earlier...you win..now lets move on..

 

Of course it works Tugboat
There have been submarines made with concrete hulls and there is a active and fairly broad research base into the construction of concrete pressure vessels for all sorts of marine application.

I don't know that anyone ever said it couldn't be done..

If I may, I think that most look at projects critically to see if they provide for the basics I keep mentioning:
Appropriate design given the materials used to meet the forces anticipated.
There are a couple of reasons you are getting a bit of a hard time here:

One- you are largely quoting or restating some of wellmers arguments.
You should read through the old threads on this- wellmer was never able to address the basic questions raised.

Two- no one really wants to discus a project unless there is evidence of a well thought out design.
Most correctly believe that a great deal of effort is for naught in these large projects if the design is not robust in that it meets the requirements of the service the vessel will be put to.

My pet peeve?

I really enjoy good engineering and problem solving.
In the case of submarine design, I take issue with the design being based on testing solely when proposed by a one off builder.
Test what?
A model?- does the tester have any ideal of how to scale forces and scant-lings between his model and the full size vessel?
Test the full size?
How many iterations can a man do?

Again- no one wants to poke holes in you. It's just the experience of professionals doesn't cause them to fall over when they see "out of the box"
They actually are more concerned that the box be filled with the basics:

"anything built must be designed so that the material used, in the structure chosen, will meet the loads imposed."

Edit- I hear you. That tug sounds like a great project.
If you don't mind we will carry on here trying to poke holes in concrete subs.
For some reason the topic draws a crowd and everyone has a good time