Re: [PSUBS-MAILIST] supercavitating small sub - request for proposals - a taker

[Paul Kreemer <paulkreemer@gmail.com>]

Dino, reader beware, but I did try your pipe in the Hull Calc spreadsheet.  I'm not an experienced user of it and am getting what I think is a bad result.  With the default steel material, I get a crush depth of just 52fsw for a 26" OD, 
0.5" shell thickness.  This is with no flanges or frames.

Here's another resource to check out though.  Roger Cortesi at MIT has a page up on the crush depth of simple cylinders.  With your shell thickness to OD ratio, 
0.0192, it looks like the pipe should handle 300m before buckling.  Just take a look at the spreadsheet - it should open fine in OpenOffice.  

BUT these formulas were used and tested with smaller cylinders and makes reference to thick-walled pressure vessels.

http://pergatory.mit.edu/rcortesi/portf/pressvesfailure/presvesfail.html
 which has a spreadsheet you can download: Simple Pressure
    Vessel Failure Modes.xls


Any comments or help?

Paul