it is about mooring line of the floating wind turbines

1. Mooring System Modeling
J.M. Jonkman
2007

2. Total Load on The Platform
• The total load on the support platform from the
contribution of all mooring lines:
• represents the pre-tension at the
fairleads from the weight of the cable not resting
on the seafloor in water. If the catenary lines
were neutrally buoyant, then would be zero.
• is the (i,j) component of the linearized
restoring matrix from all mooring lines.

3. Jonkman’s Quasi-static Module
• The Jonkman’s quasi-static module can model an
array of homogenous taut or slack catenary
mooring lines.
• It accounts for the apparent weight in fluid,
elastic stretching, and seabed friction of each
line, but neglects the individual line bending
stiffness.
• Because the module is fully coupled with FAST
and ADAMS, it also accounts for the nonlinear
geometric restoration of the complete mooring
system.

4. Module Calculation Procedure

5. Local Coordinate System

6. Analytical Formulation
• In the local coordinate system, the analytical
formulation is given in terms of two nonlinear
equations in two unknowns.
• The unknowns are the horizontal and vertical
components of the effective tension in the
mooring line at the fairlead, HF and VF,
respectively. (The effective tension is defined as
the actual cable [wall] tension plus the
hydrostatic pressure.)

7. When No Portion of The Line Rests on The Seabed:

8. When A Portion of The Mooring Line Adjacent To The Anchor Rests
on The Seabed:

9. Initial Guess In The Newton-Raphson Iteration:

10. The Horizontal And Vertical Components of The Effective Tension
At The Anchor:

11. Configuration of, And Effective Tensions Within The
Mooring Line:

12. Configuration of, And Effective Tensions Within The Mooring Line, W
A Portion of The Mooring Line Rests on The Seabed: