# Stress and Deformation Analysis of Prestressed Wound Composite Components with an Arch-Shaped Metal Liner

## TL;DR

This paper introduces a new model to analyze stress and deformation in prestressed composite components with arch-shaped metal liners, improving design accuracy.

## Contribution

The study introduces the 'additional bending moment effect' and validates a 3D finite element model for arch-shaped prestressed wound components.

## Key findings

- A 3D finite element model was developed and validated with less than 2% error compared to experiments.
- Stress distributions in arch-shaped sections are similar to circular sections, with differences under 5%.
- Deformation in arch-shaped components can be modeled as the sum of arc and straight segment deformations when the length-to-diameter ratio is less than 4.

## Abstract

The stress distribution in prestressed filament wound components plays a crucial role in determining the quality of these components during their operational lifespan. This article proposes a physical model to analyze the stress and deformation of prestressed wound composite components with arch-shaped sections. Drawing upon the principles of beam theory, we delve into the analysis of prestressed wound components with metal liners featuring arch-shaped sections. Our investigation revealed a noteworthy phenomenon termed the “additional bending moment effect” within prestressed wound components with arch-shaped sections. Furthermore, this study establishes a relationship between this additional bending moment and the external pressure. In addition, a 3D finite element (FE) model for prestressed wound components with arch-shaped sections incorporating metal liners was developed. The model’s accuracy was validated through a comparison with prestressed wound experiments, showcasing an error margin of less than 2%. In comparison with prestressed wound components with circular cross-sections under identical load and dimensional parameters, it was observed that prestressed wound components with arch-shaped sections exhibit stress distributions in the arc segments akin to their circular counterparts, with differences not exceeding 5%. Notably, when the ratio of the straight segment length to the inner diameter of the arc segment inner is less than 4, the deformation on the symmetric plane of the arc segment in an arch-shaped component can be effectively considered as the summation of deformations in equivalent-sized arc and straight segments under identical loading conditions. This yields an equivalent physical model and a streamlined analysis and design methodology for describing the deformation characteristics of prestressed wound components with arch-shaped sections.