There are a number of different element diameters you can specify when inputting geometric properties in the Rigid Riser format.
Specifically you can input values for:
This section discusses the significance of each of these diameter inputs in order to eliminate any possible ambiguity or confusion. Diameters Summary shows this information in a convenient table format.
In the Rigid Riser format, diameter data you specify is used in four ways. Firstly, it is used in calculating forces on an element from a variety of sources as part of setting up the finite element equilibrium equations. Secondly, some of the values can be used in calculating cross-section properties. Thirdly, diameter values are used in calculating hoop, bending and von Mises stress output from the results of an analysis, this being a purely postprocessing operation. Fourthly, it is used to calculate the effect of coatings. Coatings are the subject of a separate section.