Effect of thickness on the buckling strength of egg-shaped pressure hulls

ABSTRACT

This paper is devoted to a further investigation on a range of externally pressurised egg-shaped pressure hulls. Hulls are 2.561 m long, 1.767 m wide, and have uniform wall thickness varying from 10 to 80 mm with 5 mm increment. Series of numerical simulations and laboratory scale experiments are performed to systematically study the buckling of egg-shaped pressure hulls, along with the effect of wall thickness on the buckling. Volume and mass equivalent spherical pressure hulls are also proposed to make a like-for-like comparison with egg-shaped pressure hulls. The results show that egg-shaped pressure hulls seem to be applicable to deep sea manned/unmanned submersibles, especially to full ocean depth ones (11,000 m). Also, deep pressure hulls tend to buckle in an elastic–plastic regime, which is strongly affected by the wall thickness.

KEYWORDS:

• Pressure hull
• egg-shaped shell
• buckling
• wall thickness
• external pressure

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the Natural Science Foundation of Jiangsu Province ‘Bionic Study into Deep Pressure Hulls Based on Biological Properties of Eggshells’ [grant number BK20150469]; the National Natural Science Foundation ‘Research on Elastic-plastic Instability Mechanisms of Medium-thick Deep Sea Egg-shaped Pressure Hulls’ [grant number 51709132]; the Key Program of National Natural Science of China ‘Structural Reliability Analysis on the Spherical Hull of Deepsea Manned Submersibles’ [grant number 51439004]; and the General Program of National Natural Science Foundation of China ‘Study on the Design and Life Calculation Method for the Maraging Steel Sphere of Full-ocean-depth Manned Submersible’ [grant number 51679133].