Structural characteristics of corrugated sandwich rectangular pressure vessels

Rectangular cross-section pressure vessels are favored for point-to-point liquid cargo transportation due to their compact structure, stability, and high volumetric efficiency. However, they suffer from insufficient local stiffness, resulting in lower load-bearing capacity compared to circular cross-section pressure vessels. The corrugated sandwich structure offers excellent bending performance, lightweight properties, and ease of forming. This paper proposes and designs a rectangular pressure vessel enhanced with a corrugated sandwich structure. Finite element analysis is employed to study its load-bearing characteristics, and the mechanical model is simplified accordingly. A deviation of 4.55% was found through theoretical calculations, confirming the accuracy of the finite element analysis results. The new pressure vessel design increases volume by 17.2% compared to traditional designs. The ratio of the moment of inertia of the circumferential reinforcement structure ([Formula: see text]) to that of the external corrugated sandwich structure ([Formula: see text]), denoted as Π₁. As the parameter Π₁ increases, the average displacement and maximum stress show an increasing trend, stabilizing when Π₁ ≥ 1.14. With the increase of Π₂, the average displacement rises, while the maximum stress first increases and then decreases, reaching its minimum at Π₂ = 1.55.