An incompressible ber-reinforced material model for human umbilical veins

Abstract

In this project two material models are proposed for the human umbilical vein. A numerical solution method is also proposed. The purpose of this solution method is to signicantly reduce the calculation time as apposed to using generalized FE software. The numerical solution uses a nonlinear least squaresmethod to nd the material models parameters and a simpsons numerical integrationscheme to nd the solution of the analytical integrals. The method doesreproduce experimental results for the pressure radius relationship and forceradius relationship. The accuracy for the simple model was very good, as it manages to follow the pressure radii relationship. The fiber reinforced model also had a good pressure radii relationships, but as a result of adding an extra equation for the force did not manage to nd as accurate results for the force.The least squares method seems to have too many variables to find a solution without tweaking the boundary and starting conditions. As a result the method is faster but not as reliable.