OrcaFlex examples

Moorings

Below is a list of links to OrcaFlex example topics. Within each topic are a number of examples which each comprise one or more simulation files, a description pdf file, workspace files and sometimes other supporting files. The files for each example are zipped for easy download. The simulation files can be opened and viewed with the demonstration version of OrcaFlex.

Moorings

C03 Turret moored FPSO

This example shows how to model a turret moored FPSO, using a constraint to model the rotation between the turret and the vessel.

C05 Single point mooring

An OrcaFlex default vessel is moored using three legs and a short chafe chain from the connecting node. This system is often used as a temporary mooring. In OrcaFlex we aim to inspect the load on the moorings and also quantify the mooring offset for this vessel in this sea state. The simulation uses irregular waves acting for a duration of 1 hour.

C06 CALM buoy

In this example, a CALM buoy is moored by six equally spaced mooring lines. A shuttle tanker is moored to the buoy by a hawser, with fluid transfer through a floating hose. These models are coupled analysis examples.

This document also describes the ‘spar buoy short wave issue’ and presents two options for avoiding problems when modelling scenarios where the wavelength is in the order of three times the buoy’s diameter (or less).

Included are two models - the first demonstrates how the CALM buoy can be modelled as a single stack of cylinders, while the second demonstrates the use of multiple stacks of cylinders, to allow both radial and axial discretisation of the buoy’s properties.

C07 Metocean buoy in deep water

The example shows a metocean buoy moored in deep water. It is held in place by a long mooring line anchored at the seabed. A regular wave train has been applied.

C08 Fish farm

Two fish farm cages are modelled. They are connected to each other via moorings to give a 2 cell structure.

C09 Fenders

In this example, a method of modelling a quayside fender is presented. The method uses a constraint object to model the non-linear deflection and damping properties of a cell type fender. A similar approach could be used to model other types of fender e.g. pneumatic fenders.

C10 Multiple statics

This example provides a Python script and demonstrates how it can be used to perform a Multiple Statics mooring calculation.

The Multiple Statics calculation performs a series of static analyses for a grid of different positions of a vessel, and is mainly used in mooring analyses. The output would typically be tables and graphs of load-offset curves.