Structural Characteristics of Corrugated Steel Inner Walls in Liquefied Natural Gas Ship Membrane Compartments

Under high sea conditions, liquefied natural gas (LNG) ships undergo significant shaking, which can affect the deformation and stress levels in the membrane tank walls. In this work, the structural characteristics of the corrugated steel inner wall in LNG ship membrane tanks were examined, different finite element models were established, and the structural characteristics under normal conditions, high sea conditions, and defective conditions were evaluated. The results revealed that corrugated steel exhibited high stress and strain under high sea conditions, with early signs of initial yield. In the presence of defects, the corrugated steel strip experienced higher stress and strain under the same load. Particularly, at a pressure of 10 bar, the defective corrugated steel exhibited a 2.3% increase in maximum stress than the defect-free corrugated steel. Additionally, the incorporation of reinforcement into the corrugated plate significantly reduced its stress and strain. Under a pressure of 10 bar, the reinforced corrugated plate exhibited a maximum stress of 503 MPa, which was 5.1% lower than that of the non-reinforced corrugated plate. This study provides theoretical support and guidance for designing and optimizing the inner wall structure of LNG ship membrane tanks.