Geometric Properties in Flexible Riser Format |
 
|
Geometric Properties in Flexible Riser Format |
|
When using the Flexible Riser format you specify geometric property data under four headings:
•Structural properties: there are three Material Models available, Linear Elastic, Non-linear Elastic, and Hysteretic Bending
•Mass and Polar Inertia per Unit Length
•Diameter Inputs: there are four external diameter inputs and one internal diameter input
•Buoyancy Formulations: the options are Default and Distributed
All of these are now discussed in more detail. Note that the choice of buoyancy formulation has significance for some of the external diameter inputs, so you may wish to read the article on Buoyancy Formulations before reading the section discussing Diameter Inputs.
•*GEOMETRIC SETS is used to assign geometric properties to element sets (see OPTION=FLEXIBLE).
•*MOMENT-CURVATURE is used to define moment-curvature curves for non-linear materials.
•*FORCE-STRAIN is used to define force-strain curves for non-linear materials.
•*TORQUE-TWIST is used to define torque-twist curves for non-linear materials.
Note also that the old *STRESS/STRAIN keyword has effectively been superseded by these new non-linear material definition keywords which explicitly distinguish between bending, axial and torsional stiffness.
If you would like to see an example of how structural properties are defined in the Flexible Riser format, refer to C02 - Multi-Line Flexible System.