Abstract
This paper discusses two important additions under development in MoorDyn, a computationally-efficient lumped mass model for simulating the dynamics of mooring systems. The first is a means of modelling friction between mooring lines and the seabed. A simple saturated-damping approach is demonstrated, and tests with steady lateral motion show reasonable behavior from this initial implementation. The second capability under development is modelling mooring systems attached to more than one floating body. This is relevant for new design ideas that see moorings attached to multi-body structures or shared among and entire array of floating energy devices. A means of coupling about a collect of independently-moving fairlead connections has been implemented. The resulting capability is demonstrated with a scenario involving a mooring line connecting two bodies undergoing circular motions. Seabed friction is also included in the scenario, showing the effect that such friction can have in altering the mechanical power dissipated by the moorings in a shared-mooring wave energy array. Lastly, some ideas are presented for wave tank tests that could be used to validate these newly-implemented model components.