A quasi-linear method for frictional model in helical layers of bent flexible risers

This paper deals with the behaviour of two helical layers of bent flexible risers. An analytical model with frictional effects is developed to summarize the mechanical behaviour of helical armour wires. To ensure a unified process of calculation, all formulas are simplified to build up a system of quasi-linear partial differential equations. The numerical solution is determined by finite difference method. Appropriate results are shown in the paper. The geometrical quantities, slips and stresses are matched with other analytical results and found valid.