- Sep 9, 2013
- Reaction score
- Melbourne, Australia
Yes, for a pressure vessel the optimum winding angle is completely different to something representing a load bearing column or something along those lines ie. something experiencing compressive bending loads as opposed to pure tensile in all directions.Actually, a wind angle of ~55° (as shown in the video) IS optimal for my primary intended application of motor cases. You primarily need hoop strength so you want a wind angle not too far from a typical hoop wind, but you also have to have some axial strength to keep the closures in. I can dig up and link the paper I found on the subject later.
The challenge for a straight (internally pressurized) tube of composite construction is attaching the ends. You can't really optimally utilise many of the standard methods available to you for a plain alloy material; although frankenbolt retention has been utilised before with success with some composite tubing although your winding angles might need to reflect the stress distributions of typical alloy tubing than that optimised for pressure vessels as you'd be removing chunks out from the longitudinally stressed structure.
You can glue the ends in to avoid that, but then you need to be ultra careful about the design of those bonded joints with very close attention paid to the hoop *strain* of the tube.
anyway... Great Job! I'll be following with interest.