Line data: Analytic catenary

Solution grid

For a line which uses the analytic catenary representation, these data define the associated solution grid for the top end of the line:

Horizontal tension steps

These are the horizontal tension values of the solution grid. More precisely, each value specifies the horizontal component of the line tension at the closest point to the bottom end which does not lie on the seabed.

These tension values are generated at step count steps between the from and to values, spaced in a geometric progression. If the step count is zero, then only the from value is used.

Fairlead vertical offset steps

The fairlead vertical offset values of the solution grid. Each value specifies the vertical displacement of the top end of the line above/below its position in reset state.

Again, these values are generated at step count steps between the from and to values, but this time equally-spaced in an arithmetic progression. And again, if the step count is zero, then only the from value is used.

Tolerance

The relative tolerance to which the analytic catenary solution at each grid point will be computed.

View curves

The view curves button opens a graph window which allows you to select and view the analytic catenary solutions for any of the grid points.

Seabed slope

The slope of the effective flat seabed assumed for the purposes of solving the analytic catenary problem. Setting this data to ~ instructs OrcaFlex to use the slope of the seabed beneath the anchor in the direction that points from the anchor to the fairlead. This is inferred from the positions of the line ends when the model is in reset state.