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Chain |
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Chain |
A chain can be modelled in OrcaFlex by a line type with its various properties set to suitable values. Anchor chain is characterised by its nominal (bar) diameter $d$:
| Figure: | Chain geometry |
The properties of a line type to represent such a chain are given below. For the derivations of these values, click the name of the corresponding property.
| Studless | Studlink | |
|---|---|---|
| OD | $1.80 d$ | $1.89 d$ |
| ID | 0 | 0 |
| Outer contact diameter | $3.35 d$ | $3.6 d$ |
| Inner contact diameter | ~ | ~ |
| Mass/length | $19.9 d^2$ | $21.9 d^2$ (te/m for $d$ in m) |
| Axial stiffness | $0.854{\times}10^8 d^2$ | $1.01{\times}10^8 d^2$ (kN for $d$ in m) |
| Bend stiffness | 0 | 0 |
| Compression is limited | yes | yes |
| Normal drag coefficient | $2.4$ | $2.6$ |
| Normal drag diameter | $d$ | $d$ |
| Axial drag coefficient | $1.15$ | $1.4$ |
| Axial drag diameter | $d/\pi$ | $d/\pi$ |
| Normal added mass coefficient | $1.0$ | $1.0$ |
| Axial added mass coefficient | $0.5$ | $0.5$ |
| Stress diameters | ~ | ~ |
| Allowable stress | ~ | ~ |
| Friction coefficient | typically 0.4 to 0.8 depending on the seabed | |