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Beam element sensor

The Beam element sensor can be added by right-clicking on the desired element and toggle the sensor on, as shown in the picture below:

The fields of the Beam element sensor are given in the Element coordinate system (see Coordinate systems)
The moments along the principal axes are different at the two nodes defining the element. Therefore, two moments, noted i and j, are given for each principal axis

The figure below shows an example of how to interpret the Moment output around the principal axes and at the different nodes defining the element. In this example, the output analyzed is the Moment (1st principal axis), i.

Right-clicking on the element opens a pop-up window with information about this element. The top of this window shows which nodes are connected to the element and how tey are names. In this example, node i of the element corresponds to node 13 of the tubular tower.
In the Display settings, it is possible to enable the visualization of the Element Coordinate system (see Coordinate systems for more info). The axes defining the element coordinate system are then displayed, with red, green and blue colors corresponding to the axial, the 1 ^st principal and the 2 ^nd principal axes respectively. In the present example, the 1 ^st principal axis is horizontal and perpendicular to the wind (aligned with the global x-axis), as seen in the figure. Note that to facilitate the visualization of the element axes, in this example the wireframe mode has been selected (in the top ribbon of the

Simulation window ).

The Beam Element sensor provides the following fields. Fields in the Plastic-hinge diagnostics section are only populated on plastic-hinge beam elements; on regular elastic beam elements they read zero.

Field	Unit	Description
Axial force	kN	Force along the element axis
Shear force (1^st prin. axis)	kN	Shear force along the 1^st principal axis
Shear force (2^nd prin. axis)	kN	Shear force along the 2^nd principal axis
Shear force, mag.	kN	Magnitude of the shear force
Torque	kNm	Moment around the axial direction of the element
Moment (1^st prin. axis), i	kNm	Moment around the 1^st principal axis at node i
Moment (2^nd prin. axis), i	kNm	Moment around the 2^nd principal axis at node i
Moment, mag., i	kNm	Magnitude of the moment at node i
Moment (1^st prin. axis), j	kNm	Moment around the 1^st principal axis at node j
Moment (2^nd prin. axis), j	kNm	Moment around the 2^nd principal axis at node j
Moment, mag., j	kNm	Magnitude of the moment at node j
Total force (i)	kN	3-component vector representing the elastic force at node i
Max normal stress mag.	MPa	Maximum stress in the direction parallel to the axis of the element
Twist (structural)	deg	The twist of the frame element compared to its initial twist due to rotational deformation (see Frame element twist)
Twist (structural) - rad	rad	Same as above, in radians
Deformed length	m	Current length of the element, taking account the deformations
Elongation	-	Ratio of the deformed length over the initial length
Strain energy	J	Elastic strain energy currently stored in the element
Kinetic energy	J	Kinetic energy of the element
Mechanical energy	J	Sum of the kinetic energy and strain energy of the element
Deformational rotation (i)	deg	Magnitude of the rotation of node i relative to the rigid-body rotation of the element (deformation-only component)
Deformational rotation (j)	deg	Magnitude of the rotation of node j relative to the rigid-body rotation of the element (deformation-only component)
Deformational rotation (axial)	deg	Component of the deformational rotation around the axial direction of the element
Deformational rotation (1^st prin.)	deg	Component of the deformational rotation around the 1^st principal axis
Deformational rotation (2^nd prin.)	deg	Component of the deformational rotation around the 2^nd principal axis
Deformational rotation (i) - rad	rad	Same as Deformational rotation (i), in radians
Deformational rotation (j) - rad	rad	Same as Deformational rotation (j), in radians
Deformational rotation (axial) - rad	rad	Same as Deformational rotation (axial), in radians
Deformational rotation (1st prin.) - rad	rad	Same as Deformational rotation (1^st prin.), in radians
Deformational rotation (2nd prin.) - rad	rad	Same as Deformational rotation (2^nd prin.), in radians
Damping force, i	kN	Magnitude of the structural damping force at node i
Damping moment, i	kNm	Magnitude of the structural damping moment at node i
Damping force, sum	kN	Magnitude of the total structural damping force on the element (sum of contributions at nodes i and j)
Damping moment, sum	kNm	Magnitude of the total structural damping moment on the element (sum of contributions at nodes i and j)
Plastic-hinge diagnostics (populated only on plastic-hinge beam elements; read zero otherwise)
Plastic rotation (1^st prin.), i	rad	Current plastic rotation at the hinge at node i, around the 1^st principal axis
Plastic rotation (2^nd prin.), i	rad	Current plastic rotation at the hinge at node i, around the 2^nd principal axis
Plastic rotation (1^st prin.), j	rad	Current plastic rotation at the hinge at node j, around the 1^st principal axis
Plastic rotation (2^nd prin.), j	rad	Current plastic rotation at the hinge at node j, around the 2^nd principal axis
Accum. plastic rotation (1^st prin.), i	rad	Accumulated absolute plastic rotation (sum of \|Δθ_p\|) at the hinge at node i, 1^st principal axis
Accum. plastic rotation (2^nd prin.), i	rad	Accumulated absolute plastic rotation at the hinge at node i, 2^nd principal axis
Accum. plastic rotation (1^st prin.), j	rad	Accumulated absolute plastic rotation at the hinge at node j, 1^st principal axis
Accum. plastic rotation (2^nd prin.), j	rad	Accumulated absolute plastic rotation at the hinge at node j, 2^nd principal axis
Hinge yielded (1^st prin.), i	-	1 once the hinge at node i (1^st principal axis) has yielded (accumulated plastic strain exceeds 1% of the elastic yield strain), 0 otherwise
Hinge yielded (2^nd prin.), i	-	1 once the hinge at node i (2^nd principal axis) has yielded, 0 otherwise
Hinge yielded (1^st prin.), j	-	1 once the hinge at node j (1^st principal axis) has yielded, 0 otherwise
Hinge yielded (2^nd prin.), j	-	1 once the hinge at node j (2^nd principal axis) has yielded, 0 otherwise
Effective yield moment (1^st prin.), i	kNm	Current yield moment at the hinge at node i (1^st principal axis) including isotropic hardening
Effective yield moment (2^nd prin.), i	kNm	Current yield moment at the hinge at node i (2^nd principal axis) including isotropic hardening
Effective yield moment (1^st prin.), j	kNm	Current yield moment at the hinge at node j (1^st principal axis) including isotropic hardening
Effective yield moment (2^nd prin.), j	kNm	Current yield moment at the hinge at node j (2^nd principal axis) including isotropic hardening
Moment / yield ratio (1^st prin.), i	-	\|M\| / M_y,eff at the hinge at node i, 1^st principal axis (ratio of current moment magnitude to effective yield moment)
Moment / yield ratio (2^nd prin.), i	-	\|M\| / M_y,eff at the hinge at node i, 2^nd principal axis
Moment / yield ratio (1^st prin.), j	-	\|M\| / M_y,eff at the hinge at node j, 1^st principal axis
Moment / yield ratio (2^nd prin.), j	-	\|M\| / M_y,eff at the hinge at node j, 2^nd principal axis
Dissipated energy (sum)	J	Total energy dissipated through plastic deformation, summed over all four hinges of the element
Reversal count (1^st prin.), i	-	Number of plastic-strain-rate sign reversals observed at the hinge at node i, 1^st principal axis
Reversal count (2^nd prin.), i	-	Number of plastic-strain-rate sign reversals observed at the hinge at node i, 2^nd principal axis
Reversal count (1^st prin.), j	-	Number of plastic-strain-rate sign reversals observed at the hinge at node j, 1^st principal axis
Reversal count (2^nd prin.), j	-	Number of plastic-strain-rate sign reversals observed at the hinge at node j, 2^nd principal axis

Note: the output Max normal stress and Max shear stress are only displayed for elements whose cross-section has a known geometry. For the default blades for example, only the outer shape of the blade elements (i.e. the geometry of the airfoils) is known, whereas the internal structure of the blade is now known. Therefore it is not possible to calculate the maximum stresses for blade elements.