A simple technique for characterizing flexible materials using pressurized tubes

Abstract

This work numerically and experimentally studies the deformation of flexible tubes under positive transmural pressure. The numerical analysis uses asymmetric static simulations with a neo-Hookean model, defined by the shear modulus, validated through experiments with two different materials. A dimensionless study was conducted to evaluate the variation in tube volume as a function of transmural load (the ratio of transmural pressure per shear modulus), considering different lengths and thicknesses. For thin-walled conducts, a reduction of one order of magnitude in thickness requires a smaller transmural load of the same order to achieve the same deformation. Additionally, length does not affect deformation for relatively thin-walled conducts. So, for flexible conducts long enough and thin enough, the volumetric deformation as a function of the ratio of the transmural load to dimensionless thickness collapses into a single curve, simplifying the prediction of deformation. This curve allows the shear modulus to be estimated with a single experiment using a manometer, facilitating the characterization of these materials.