Tower
=====================

The :code:`tower` is defined similar to the :code:`blade`.

.. literalinclude:: ../../test/turbine/IEA-15-240-RWT.yaml
    :start-after: C_PM:
    :end-before: monopile:

:code:`reference_axis` : Object
    The field :code:`reference_axis` describe the three-dimensional shape of the reference axis of the tower via three sub-fields, namely :code:`x`, :code:`y`, and :code:`z`. The three sub-fields contain the pairs of arrays :code:`grid` and :code:`values`. The former is nondimensional, while the latter is expressed in meters. :code:`x`, :code:`y`, and :code:`z` are expressed in the tower reference system, with :code:`x` parallel to the ground pointing downwind, :code:`y` parallel to the ground and to the rotor plane, and :code:`z` perpendicular to the ground pointing upwards. Standard towers are only defined along :code:`z`.

:code:`outer_diameter.values` : Array of floats, m
    Diameters of the tower defined from tower base (grid = 0) to tower top (grid = 1).

:code:`drag_coefficient.values` : Array of floats
    This is the equivalent drag coefficient used to compute the aerodynamic forces generated by the tower immersed in the flow. Standard aeroelastic solvers use this parameter.

:code:`outfitting_factor` : Float
    Multiplier of tower mass to account for the mass of the auxiliary systems, such as stairs, elevator, paint, etc. This can be used to convert the mass of the steel cylinders to the total mass of the tower.

The field :code:`layers` mimic the same field of the blade.