An analytical solution for an inflated orthotropic membrane tube with an arbitrarily oriented orthotropy basis

In this paper, an analytical solution is proposed for a pressurized cylindrical tube made of an orthotropic membrane, with the orthotropy directions oriented at an arbitrary angle, not necessarily parallel to the tube axis. The formulation is made in the framework of finite deformations and results in a system of three non-linear equations, giving the final radius, length and rotation of the cross-sections of the tube, in the deformed configuration. The set of equations is solved for balanced and unbalanced materials, with various internal pressures and orientations of the membrane. The numerical results obtained are shown to agree very well with those of an independent finite element code.