Does anyone know how to calculate the rupture pressure of a tank if you know the internal pressure, wall thickness, and strength of the material that makes up the tank?
I'm building a small rocket motor and need to know how thick the combustion chamber needs to be. I also need to know what pressure to make the emergency shutoff valves begin cutting fuel and dumping helium into the chamber.
thanks guys.
Pressurised Tank Rupture question
Moderator: Alyrium Denryle
Pressurised Tank Rupture question
Sì! Abbiamo un' anima! Ma è fatta di tanti piccoli robot.
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SWPIGWANG
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If you know the internal pressure, you can calculate the force on each part of the chamber by mutiplying the area. However the total stress on the chamber would be beyond my skills as it involves intergrating the whole area of the chamber and than with fancy usage of F=ma to balance the forces out. The exact calculation depends on the shape and simple shapes can be easy to calcuate but complex ones are effectively impossible without CAD/CAM.
A circular cylinder chamber should be fairly easily to calcuate, as the stress would simply be the radius times the pressure (tension=r*p) though the exact derivation requires calculus that I am unable to do.
A circular cylinder chamber should be fairly easily to calcuate, as the stress would simply be the radius times the pressure (tension=r*p) though the exact derivation requires calculus that I am unable to do.
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AdmiralKanos
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Calculate the hoop stress on the cylindrical walls and the tensile stress on the connection between the cylindrical wall and the endcap.
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But now, you shall witnesss ... its dismemberment!
"This is what happens when you use trivia napkins for research material"- Sea Skimmer on "Pearl Harbour".
"Do you work out? Your hands are so strong! Especially the right one!"- spoken to Bud Bundy
I'll be PMing you if I don't find anything about hoop stress on Google. And then I'll fine you one imaginary "useless contribution of information" point!AdmiralKanos wrote:Calculate the hoop stress on the cylindrical walls and the tensile stress on the connection between the cylindrical wall and the endcap.
*real quick edit*
Mike, I'd like to say that engineers kick ASS.
First search result on Google:
::kneels:: Thank you O' Mighty One.http://www.tsi.dot.gov/divisions/pipeline/glossary/h/hoop_stress.htm wrote:HOOP STRESS (Barlow?s Formula): The stress in a pipe wall acting circumferentially in a plane perpendicular to the longitudinal axis of the pipe and produced by the pressure of the fluid in the pipe. Hoop stress calculation:
S=PD/2t
S=hoop stress, in psi
P=internal pressure
D=outside diameter of the pipe in inches
t=normal wall thickness, in inches
dgjhjkgh I found something else. Spherical pressure vessels work based on S=PR/2t. This is great. Very very good.
Sì! Abbiamo un' anima! Ma è fatta di tanti piccoli robot.