# A numerical simulation approach for inflatable asymmetric geometries of orthotropic fabrics

## TL;DR

This paper introduces a simulation framework to design inflatable structures with accurate geometry and load-bearing predictions.

## Contribution

A new framework for predicting the behavior of orthotropic fabrics in inflatable structures under various loads.

## Key findings

- The framework accurately predicts the geometry and deformation of inflatable structures.
- Validation with 3D scanning shows good agreement between simulations and experiments.
- The model accounts for weld anisotropy, geometric nonlinearity, and internal reinforcements.

## Abstract

Inflatable structures are lightweight, easily transported, manufactured, and deployed. These advantages make them widely applicable in civil, aerospace, and recently in wind energy applications. They are also characterized by large deviations between the un-inflated and inflated geometries, making the design process of a structure with well specified target geometry under different loading conditions very challenging. This paper presents a comprehensive framework to predict the geometry of polyvinyl chloride coated polyester fabrics and their behavior under loads. The presented framework includes detailed characterization of the material properties to be fed to commercially available software for FEA of inflatable structures. The developed model is then used to predict the ability of the structure to withstand loads without failure or wrinkling. The framework is validated against 3D scanning of the inflated geometry of four different cases which are chosen to represent different levels of complexity including weld anisotropy, geometric nonlinearity in asymmetric forms, and the effect of internal reinforcements. Comparisons between numerical predictions and experimental outcomes demonstrate the framework’s ability to capture deformation and strain behavior for complex inflatable structures. The proposed workflow provides designers with a valuable tool to design and build inflatables with a higher level of dimensional accuracy and load-bearing capacity, enabling applications beyond current limitations.

The online version contains supplementary material available at 10.1038/s41598-026-40016-5.