This data record defines the rotation axis direction for the large angle stability calculation. Rotation Axis is the axis that the structure actively rotates along, during the large angle stability calculation. It is always located on the water plane. Aqwa calculates the large angle stability along rotation axes of different directions.
2 5 7 11 16 21 31 41
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|X| | |LAAX|XXXXX| | | |
- --- -- ---- ----- ----- ---------- ---------- --------
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| | | | |_(3)End Direction of Rotation Axes (E10.0)
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| | | |_(2)Start Direction of Rotation Axes (E10.0)
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| | |_(1)Number of Rotation Axes (I5)
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| |_Compulsory Data Record Keyword (A4)
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|_Optional User Identifier (A2)
(1)-(3) together define a sequence of direction angles with constant angular increment.
(1) is the total number of rotation axes from the start direction set in (2) to the end direction set in (3).
(2)-(3) give the range of the angular directions of rotation axes. (2) is the start direction angle (in degrees) while (3) is the end direction angle (in degrees). Rotation axis direction is defined in the OXY plane of the fixed reference axes (FRA). The direction is defined as the angle between the rotation axis and the positive global X-axis measured anti-clockwise. For example, the rotation axis direction angle is 0 when the rotation axis is along the positive X-axis of the global axes and 90 degrees when along the positive Y-axis of the global axes. The default values of (2) and (3) are both zero degrees.
Note:
If (1)-(3) are all empty, the rotation axis direction is set to zero degrees.
If the number of rotation axes is set by (1) and the range set by (2) and (3) are not consistent, the setting is based on the direction range set by (2) and (3).
Only one LAAX data record is required for each structure. Subsequent ones, starting from the second data record, will be ignored by the program.