Manufacturing Imperfection Sensitivity Analysis of Spherical Pressure Hull for Manned Submersible

作者：Pranesh Bhaskaran^*; Sathianarayanan Dharmaraj; Ramesh Sethuraman; Ramadass Gidugu Ananda

来源：Marine Technology Society Journal, 2013, 47(6): 64-72.

• manned submersible
• pressure hull
• buckling
• imperfection
• finite element analysis

Any pressure hull invariably has imperfections as a result of the manufacturing procedure. Imperfections in a spherical pressure hull are the basis for localized buckling and deformation behavior. Numerical analysis and analytical calculations are carried out to predict the buckling behavior and strength of a pressure hull made of titanium alloy (Ti-6Al-4V) for both perfect and imperfect pressure hulls. Finite element analysis is carried out for different imperfection angles to see the effect on strength and buckling. Results of numerical analysis show that there is considerable reduction in both buckling pressure and strength as a result of imperfections. Hence, allowable deviation due to imperfection for a spherical pressure hull has to be considered for thickness calculations.
Abbreviations:
P external pressure (Design pressure)
D-m mean diameter of the pressure hull
R-m mean radius of the pressure hull
R-i imperfect radius of the pressure hull
t thickness of the pressure hull
Delta R imperfect deviation
delta imperfection angle
sigma hoop stress
P-y pressure at yield strength of the material
P-b buckling pressure
E Young's modulus of the material
mu Poisson's ratio
MSM meters of sea water
APDL ANSYS Parametric Design Language

• 出版日期2013-12