Support section examples

This section gives examples of how typical support sections are defined. Many different concepts use non-conventional configurations, so this section is only meant as an indication of how to generate the most common types of wind turbines. The format to follow for each keyword is given in the  Keywords  section.

In general, the tubular tower is the support section that holds the RNA at its highest node. To model onshore turbines, it is common to have a tubular tower directly mounted onto the ground. For offshore turbines, the tubular tower is mounted on a monopile and for floating turbines the tower is mounted on the floater itself. The input file that defines a tubular tower is generaly defined with the following keyword sections:

Keyword	Notes
Name	-
Orientation	-
RNA nodes	If no node is specified, the tubular tower will have no RNA
Substructure node	This only applies for tubular towers connected to another support section, such as a monopile, a truss tower or a floater
Materials	-
Circular hollow cross section	Different types of cross sections can be defined, but Circular hollow  are the most common
Nodes	-
Slave nodes	This is typically used to create hinges
Members	-
Supports	In general, this is only used for standalone tubular towers. If supports are specified for a tower on another support section, the node will have some or all of its degrees of freedom constrained
Springs	Springs (linear or non-linear) are generally applied when part of the tubular tower is below the ground
Non-linear springs	-
Damping loads	-
Transforms	Applies a rotation, translation or scaling when importing the support section into Ashes

The monopile is the most common type of foundation for offshore wind turbines. It generally extends below the seabed and has the tubular tower on its highest node.

Keyword	Notes
Name	-
Orientation	-
Tower node	If this is left empty, the monopile will not have any tubular tower
Materials	-
Circular hollow cross section	Different types of cross sections can be defined, but  Circular hollow  are the most common
Nodes	-
Slave nodes	This is typically used to create hinges
Members	-
Supports	Specifies how the monopile is connected to the ground. It is common to have it fixed at the seabed, or to have it pinned below the seabed together with springs.
Springs	Springs (linear or non-linear) are generally applied when part of the monopile is below the ground
Non-linear springs	-
Damping loads	-
Transforms	Applies a rotation, translation or scaling when importing the support section into Ashes

Another type of support section is the truss tower. This can be used as a foundation offshore (i.e. with a tubular tower on top) or as a standalone support section (i.e. with the RNA directly on top)

Keyword	Notes
Name	-
Orientation	-
RNA nodes	If no node is specified, the truss tower will have no RNA
Tubular tower node	If this is left empty, the monopile will not have any tubular tower
Materials	-
Circular hollow cross section	Different types of cross sections can be defined, but  Circular hollow  are the most common
Nodes	-
Slave nodes	This is typically used to create hinges
Members	-
Supports	Specifies how the tubular tower is connected to the ground. It is common to have it fixed at the seabed, pt to have it pinned below the seabed together with springs.
Springs	Springs (linear or non-linear) are generally applied when part of the tubular tower is below the ground
Non-linear springs	-
Damping loads	-
Transforms	Applies a rotation, translation or scaling when importing the support section into Ashes

The floater is generally moored to the seabed via mooeing lines. It can have one or many tubular towers that will have the RNA on top.

Keyword	Notes
Name	-
Orientation	-
Mooring lines	If left empty, the floater will have no mooring lines. This can be relevant when the floater needs to be tested with linear springs instead of mooring.
Tubular tower node	If this is left empty, the floater will not have any tubular tower. For multi-rotor floaters it is common to have more than one tubular tower
Materials	-
Circular hollow cross section	Different types of cross sections can be defined, but  Circular hollow  are the most common
Nodes	-
Slave nodes	This is typically used to create hinges
Members	-
Supports	This is typically left empty since the floater is moored to the seabed
Springs	This is typically left empty since the floater is moored to the seabed
Non-linear springs	-
Damping loads	-
Transforms	Applies a rotation, translation or scaling when importing the support section into Ashes

The mooring lines can be created from file, for example to add point masses.

Keyword	Notes
Materials	-
Circular solid cross section	Different types of cross sections are available, but the circular solid is the most common for mooring lines
Line section	-