Cylindrical Shells (shells)
Purpose
Screen thin cylindrical shells under internal pressure, axial force and bending moment using membrane theory plus von Mises combined stress.
Physics & theory
For a thin cylinder of mean radius and wall thickness , hoop stress from internal pressure is . Closed ends add axial membrane stress . External axial load and bending add further normal stress. von Mises equivalent stress combines hoop, axial and bending components for yield screening.
Governing equations
Numerical method
Closed-form membrane and simplified beam bending deflection estimate via solveShellEngine.
Inputs
| Parameter | Description |
|---|---|
radius, thickness, length | Shell geometry |
internalPressure, axialForce, bendingMoment | Loads |
endCondition | Open or closed ends |
allowableStress | Design allowable |
Outputs
- Hoop, axial, bending and von Mises stress; safety factor; indicative deflection; status message.
Design codes & checks
- Indicative: Membrane + von Mises screening
- US/EU: ASME BPVC / EN 13445 context (screening only)
Assumptions & limitations
- Thin-shell theory (); no nozzle, knuckle or buckling under external pressure.
- User supplies load combinations and factors.
References
- Roark, R. J., & Young, W. C. Formulas for Stress and Strain, Ch. 7.
- ASME BPVC Section VIII — pressure vessel design context.