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Prescribed Rotations

Loading in cylindrical frame : imposed rotations - radial displacements (around a moving axis)

Displacements and rotations imposed with respect to an axis are extensions of imposed displacements (translations) and are used to rotate/move a set of nodes around an axis, which can be moving. As for displacements, this is done with LoadingSet. The motion of the axis is defined in the LoadingSet.

Translation of rotation axis

(axis defined by points p1 and p2):

loadingset.define(p1, Field1D(TX,RE), dx1, fctX1)
loadingset.define(p1, Field1D(TY,RE), dy1, fctY1)
loadingset.define(p1, Field1D(TZ,RE), dz1, fctZ1)
loadingset.define(p2, Field1D(TX,RE), dx2, fctX2)
loadingset.define(p2, Field1D(TY,RE), dy2, fctY2)
loadingset.define(p2, Field1D(TZ,RE), dz2, fctZ2)

`p1`	reference of the origin of the axis
`dx1`, `dy1`, `dz1`	displacements of p1
`fctX1`, `fctY1`, `fctZ1`	Functions y=f(t) of the displacement of p1
`p2`	reference of the end of the axis
`dx2`, `dy2`, `dz2`	displacements of p1
`fctX2`, `fctY2`, `fctZ2`	Functions y=f(t) of the displacement of p2

Case #1: Radial displacement imposed with respect to the axis

loadingset.defineRad(gObject, Field1D(TX,RE), p1, p2, ampl, fct)

`gObject`	Geometric entity
`field`	name of the variable which is concerned by the motion
`ampl`	amplitude
`fct`	Functions y=f(t) (temporal dependency)
`p1`	reference of the origin of the axis
`p2`	reference of the end of the axis

Case #2: Rotation imposed around the axis

loadingset.defineRot(gObject, field, p1, p2, option, ampl, fct)

`gObject`	Geometric entity
`field`	name of the variable which is concerned by the motion (only `Field3D(TXTYTZ,RE)` allowed)
`ampl`	amplitude
`fct`	Functions y=f(t) (can depend on time and position)
`p1`	reference of the origin of the axis
`p2`	reference of the end of the axis
`option`	= `False` : the boundary condition is a given angle, in degrees = `True` : the boundary condition is a given angular speed, in degrees/second

Case #3: 2 successives Rotations imposed around 2 axis

loadingset.defineRot2(gObject, field, axe1, ampl1, fct1, axe2, ampl2, fct2, option)

`gObject`	Geometric entity
`field`	name of the variable which is concerned by the motion (only `Field3D(TXTYTZ,RE)` allowed)
`axe1`	first axe of rotation (mtGeoAxe object)
`ampl1`	amplitude first rotation
`fct1`	Functions y=f(t) of the first rotation (can only depend on time)
`axe1`	second axe of rotation (mtGeoAxe object)
`ampl1`	amplitude second rotation
`fct1`	Functions y=f(t) of the second rotation (can only depend on time)
`option`	= `False` : the boundary condition is a given angle, in degrees = `True` : the boundary condition is a given angular speed, in degrees/second

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