关键字_BOUNDARY_PRESCRIBED_MOTION

*BOUNDARY_PRESCRIBED_MOTION_OPTION1_{OPTION2 }

(*边界_规定_运动_选项1{OPTION2})

Available options for OPTION1 include:

(选项1的可用选项包括：)

NODE (节点)

SET (集合)

SET_BOX (体集合)

RIGID (刚体)

RIGID_LOCAL (刚体_局部)

OPTION2 allows an optional ID to be given that applies either to the single node,

node set or a rigid body:

(选项2允许提供适用于单个节点、节点集或刚体的可选ID：)

ID

If a heading is defined with the ID, then the ID with the heading will be written at the

beginning of the ASCII file, BNDOUT.

(如果标题是用ID定义的，那么带有标题的ID将写入ASCII文件BNDOUT的开头。)

注：BNDOUT(作用：Boundary Condition forces and energy)参考database ASCII

Purpose:Define an imposed nodal motion (velocity, acceleration, or

displacement)on a node or a set of velocities and displacements

can be imposed on rigid bodies. If the local option is active the motion is

prescribed with respect to the local coordinate system for the rigid body

(See variable LCO for keyword*MAT_RIGID).Translational nodal velocity

and acceleration specifications for rigid body nodes are allowed and are

applied as described at the end of this section. For nodes on rigid bodies

use the NODE option. Do not use the NODE option in r-adaptive problems

since the node ID's may change during the adaptive step.

(用途：定义在一个或一组节点上施加的节点运动（速度、加速度或位移）。速度和位移也可以施加在刚体上。如果“局部”选项处于激活状态，则根据刚体的局部坐标系指定运动（请参见关键字*MAT_RIGID的变量LCO）。允许刚体节点的平移节点速度和加速度规范，并按照本节末尾所述进行应用。对于刚体上的节点，请使用“节点”选项。请勿在自适应问题中使用节点选项，因为在自适应步骤中节点编号可能会更改。)

The following card is read if and only if the ID option is specified. The

second card is required.

(当且仅当指定了ID选项时，才会读取以下卡片。第二张卡片是必需的。)

For the SET_BOX option, define the following additional card

(对于定义BOX选项，定义以下附加卡)

Card is required if DOF=9,10,11 on the first card or VAD=4. If DOF<9 and VAD<4,

skip this card.

(如果第一张卡片上的自由度=9,10,11或Velocity/Acceleration/Displacement=4，则需要该卡片。如果自由度<9且Velocity/Acceleration/Displacement<4，则忽略此卡片。)

VARIABLE(变量) DESCRIPTION(说明)

Optional PRESCRIBED MOTION set ID to

ID

(编号)

which this node, node set, or rigid body belongs.

This ID does not need to be unique.

(可选定义节点、节点集或刚体的规定运动ID。此ID不需要是唯一的。)

An optional descriptor for the given ID that will

HEADING

(标题)

be written into the D3HSP file and the

BNDOUT file.

(给定ID的可选描述，将写入D3HSP文件和BNDOUT文件。)

Node ID (NID in *NODE), nodal set ID (SID in

*SET_NODE) , or part ID(PID in *PART) for a

typeID

(ID类型)

rigid body.

(刚体的节点ID（节点ID在*节点中）、节点集ID（节点集ID在*节点集中）或零件ID（零件ID在*零件中）。)

Applicable degrees-of-freedom:(适用自由度：)

EQ.1: x-translational degree-of-freedom,

(等于1:x位移自由度，)

EQ.2: y-translational degree-of-freedom,

(等于2:y位移自由度，)

EQ.3: z-translational degree-of-freedom,

(等于3:z位移自由度，)

EQ.4: translational motion in direction given

DOF

(自由度)

by the VID. Movementon plane normal to the

vector is permitted.

(等于4：在矢量编号给出的方向上的平移运动。允许在垂直于矢量的平面上移动。)

EQ.-4: translational motion in direction given by

the VID. Movement on plane normal to the

vector is not permitted. This option does not

apply to rigid bodies.

(等于-4：在矢量编号给出的方向上的平移运动。不允许在垂直于矢量的平面上移动。此选

项不适用于刚体。)

EQ.5: x-rotational degree-of-freedom,

(等于5:x旋转自由度，)

EQ.6: y-rotational degree-of-freedom,

(等于6:y旋转自由度，)

EQ.7: z-rotational degree-of-freedom,

(等于7:z旋转自由度，)

EQ.8: rotational motion about a vector parallel

to vector VID. Rotation about the normal axes is

permitted.

(等于8：关于平行于VID的矢量的旋转运动。允许绕法向轴旋转。)

EQ.-8: rotational motion about a vector parallel

to vector VID. Rotation about the normal axes is

not permitted. This option does not apply to

rigid bodies.

(等于-8：关于平行于VID的矢量的旋转运动。不允许绕法向轴旋转。此选项不适用于刚体。)

EQ.9: y/z degrees-of-freedom for node rotating

about the x-axis at location

(OFFSET1,OFFSET2) in the yz-plane, point

(y,z). Radial motion is NOT permitted. Not

applicable to rigid bodies.

(等于9：在yz平面的节点（y，z）（坐标值1，坐标值2）绕x轴旋转。不允许径向运动。不适用于刚体。)

EQ.-9: y/z degrees-of-freedom for node rotating

about the x-axis at location

(OFFSET1,OFFSET2) in the yz-plane, point

(y,z). Radial motion is permitted. Not applicable

to rigid bodies.

(等于-9：在yz平面的节点（y，z）（坐标值1，坐标值2）绕x轴旋转。允许径向运动。不适用于刚体。)

EQ.10: z/x degrees-of-freedom for node rotating

about the y-axis at location

(OFFSET1,OFFSET2) in the zx-plane, point

(z,x). Radial motion is NOT permitted. Not

applicable to rigid bodies.

(等于10:在zx平面的节点（z，x）（坐标值1，坐标值2）绕y轴旋转。不允许径向运动。不适用于刚体。)

EQ.-10: z/x degrees-of-freedom for node

rotating about the y-axis at location

(OFFSET1,OFFSET2) in the zx-plane, point

(z,x). Radial motion is permitted. Not applicable

to rigid bodies.

(等于-10：在zx平面的节点（z，x）（坐标值1，坐标值2）绕y轴旋转。允许径向运动。不适用于刚体。)

EQ.11: x/y degrees-of-freedom for node rotating

about the z-axis at location

(OFFSET1,OFFSET2) in the xy-plane, point

(x,y). Radial motion is NOT permitted. Not

applicable to rigid bodies.

(等于11：在xy平面的节点（x，y）（坐标值1，坐标值2）绕z轴旋转。不允许径向运动。不适用于刚体。)

EQ.-11: x/y degrees-of-freedom for node

rotating about the z-axis at location

(OFFSET1,OFFSET2) in the xy-plane, point

(x,y). Ra-dial motion is permitted. Not

applicable to rigid bodies.

(等于-11：在xy平面的节点（x，y）（坐标值1，坐标值2）绕z轴旋转。允许径向运动。不适用于刚体。)

Velocity/Acceleration/Displacement flag: (速度/加速度/位移标志：)

EQ.0: velocity (rigid bodies and nodes), (等于VAD

0：速度（刚体和节点），)

(Velocity/Acceleration/Displacemen)

EQ.1: acceleration (rigid bodies and nodes), (等于1：加速度（刚体和节点），)

EQ.2: displacement (rigid bodies and nodes).(等于2：位移（刚体和节点）。)

EQ.3: velocity versus displacement (rigid bodies

and nodes) (等于3：速度相对位移（刚体和节点）)

EQ.4: relative displacement (rigid bodies only)

(等于4：相对位移（仅刚体）)

Load curve ID to describe motion value versus

time, see

*DEFINE_CURVE,

*DEFINE_CURVE_FUNCTION,

or *DEFINE_FUNCTION.

If LCID refers to *DEFINE_FUNCTION, the

LCID

(Load curve ID)

function can have only time

as an argument, e.g., f(t)=10.*t. See BIRTH

below.

(加载曲线ID描述运动相对时间的关系，请参见*定义_曲线、*定义_曲线函数或*定义_函数。如果LCID引用*定义_函数，则该函数只能将时间作为参数，例如。f（t）=10.*t。见下面的激活。)

SF

(scale factor)

VID

(Vector ID)

Load curve scale factor. (default=1.0)

(加载曲线比例系数(默认值=1.0）)

Vector ID for DOF values of 4 or 8, see

*DEFINE_VECTOR.

(矢量ID对于自由度为4或8时，请参见*定义_矢量。)

DEATH

(结束)

Time imposed motion/constraint is removed:

(强制的运动/约束结束时间：)

EQ.0.0: default set to 1028

(等于0.0：默认设置为1028)

Time imposed motion/constraint is activated

starting from the initial abscissa value of the

curve or function (*DEFINE_FUNCTION).

BIRTH

(激活)

Warning: BIRTH is ignored if the LCID is

defined as a function, i.e., *DEFINE

_CURVE_FUNCTION.

(强制运动/约束从曲线或函数（*定义_函数）的初始横坐标值开始激活。警告：如果LCID

定义为函数，则忽略激活。例如,*定义_曲线_函数。)

A box ID defining a box region in space in

which the constraint is activated. Only the nodes

falling inside the box will be applied the

prescribed motion. If LCBCHK is not defined,

the box volume is reevaluated every time step to

determine the nodes for which the prescribed

BOXID

motion is active. This reevaluation of the

volume is referred to as a “box-check”.

(一个BOXID，用于定义空间中激活约束的区域。只有落在区域内的节点才会应用于指定的运动。如果未定义LCBCHK，则每个时间步都会重新计算长方体体积，以确定指定运动处于活动状态的节点。这种重新评估称为“box-check”。)

Optional load curve allowing more flexible and

efficient use of SET_BOX option. Instead of

performing box-check at every time step,

discrete box-check times could be given as

X-values of LCBCHK. LCBCHK’s Y-values

specify corresponding death times. For example,

a curve with points (20,30) and (50,70) will

result in two box checks. The first will occur at

20, and the prescribed motion will be active

LCBCHK

from 20 to 30. The second will occur at 50, and

the prescribed motion will be active from 50 to

70. A Y-value of “0” means the prescribed

mot ion will stay active until next box-check.

For example, an additional 3 rd point of (90,0)

will lead to another box-check at 90, and the

prescribed motion will be active from 90 until

the end of the simulation.

(可选负载曲线，允许更灵活、更高效地使用设置BOX选项。不必在每个时间步执行box-check，离散的box-check时间可以作为LCBCHK的X值给出。LCBCHK的Y值指定

了相应的结束时间。例如，点（20,30）和（50,70）的曲线将导致两个box-check。第一个将在20时激活，规定的运动将在20到30时激活。第二个将在50时发生，规定的运动将在50到70时激活。Y值“0”表示规定的运动将保持激活状态，直到下一个box-check选中为止。例如，额外的第三个点（90,0）将导致在90处进行另一个box-check，并且指定的运动将从90处激活，直到模拟结束。)

Time offset flag for the SET_BOX option:(设置BOX选项的时间偏移标志：)

EQ.1: the time value of the load curve, LCID,

TOFFSET

(时间偏移)

will be offset by the time when the node enters

the box,

(等于1：加载曲线的时间值，当节点进入BOX,LCID将指定时间偏移，)

EQ.0: no time offset is applied to LCID(等式0：没有时间偏移应用于LCID)

OFFSET1

(偏移1)

OFFSET2

(偏移2)

MRB

(Master rigid body)

NODE1

(节点1)

NODE2

(节点2)

Remarks:(附注)

When DOF=5, 6, 7, or 8, nodal rotational degrees-of-freedom are prescribed in the

case of deformable nodes ( OPTION1 =NODE or SET) whereas body rotations are

prescribed in the case of a rigid body ( OPTION1 =RIGID). In the case of a rigid

body, the axis of prescribed rotation always passes through the body's center of mass.

Offset for DOF types 9-11 (y, z, x direction)

(自由度类型9-11的偏移（y、z、x方向）)

Offset for DOF types 9-11 (z, x, y direction)

(自由度类型9-11的偏移（z、x、y方向）)

Master rigid body for measuring the relative

displacement.

(用于测量相对位移的主刚体。)

Optional orientation node, n1, for relative

displacement

(相对位移的可选方向节点n1)

Optional orientation node, n2, for relative

displacement

(相对位移的可选方向节点n2)

For |DOF|=8, the axis of the prescribed rotation is parallel to vector VID. To prescribe

a body rotation of a set of deformable nodes, with the axis of rotation parallel to

global axes x, y, or z, use OPTION1 =SET with |DOF| = 9, 10, or 11, respectively.

The load curve scale factor can be used for simple modifications or unit adjustments.

(当DOF=5、6、7或8时，在可变形节点（选项1=节点或集合）的情况下规定节点旋转自由度，而在刚体（选项1=刚体）的情况下规定旋转自由度。对于刚体，规定的旋转轴始终通过刚体的质心。对于| DOF |=8，规定旋转轴平行于矢量VID。要指定一组可变形节点的主体旋转，且旋转轴平行于全局x、y或z轴，在| DOF |=9、10或11时使用选项1=集合。负荷曲线比例系数可用于简单修改或单位调整。)

The relative displacement can be measured in either of two ways:

(可通过以下两种方式之一测量相对位移：)

1. Along a straight line between the mass centers of the rigid bodies,

(1. 沿刚体质心之间的直线，)

2. Along a vector beginning at node n1 and terminating at node n2.

(2. 沿着节点n1开始节点n2终止的向量。)

With option 1, a positive displacement will move the rigid bodies further apart, and,

likewise a negative motion will move the rigid bodies closer together. The mass

centers of the rigid bodies must not be coincident when this option is used. With

option 2 the relative displacement is measured along the vector, and the rigid bodies

may be coincident. Note that the motion of the master rigid body is not directly

affected by this option, i.e., no forces are generated on the master rigid body.

(在选项1中，正向位移将使刚体进一步分开，同样，负向位移将使刚体更靠近。使用此选项时，刚体的质心不得重合。使用选项2，沿矢量测量相对位移，刚体可能重合。请注意，主刚体的运动不受此选项的直接影响，例如，不会在主刚体上生成力。)

The activation time, BIRTH, is the time during the solution that the constraint begins

to act. Until this time, the prescribed motion card is ignored. The function value of

the load curves will be evaluated at the offset time given by the difference of the

solution time and BIRTH, i.e., (solution timeBIRTH). Relative displacements that

occur prior to reaching BIRTH are ignored. Only relative displacements that occur

after BIRTH are prescribed.

(激活时间BIRTH是求解期间约束开始起作用的时间。在此之前，将忽略指定的运动卡片。载荷曲线的函数值将在求解时间和激活时间之差给出的偏移时间进行

评估，例如(求解—激活时间）。激活前发生的相对位移将被忽略。仅规定激活后发生的相对移位。)

When the constrained node is on a rigid body, the translational motion is imposed

without altering the angular velocity of the rigid body by calculating the appropriate

translational velocity for the center of mass of the rigid body using the equation:

(当受约束节点位于刚体上时，在不改变刚体角速度的情况下施加平移运动，通过使用以下等式计算刚体质心的适当平移速度：)

where

vcmis the velocity of the center of mass,

vnodeis the specified nodal velocity,

is the angular velocity of the rigid body,

xcmis the current coordinate of the mass

center, and

xnodeis the current coordinate of the nodal point. Extreme care must be

used when prescribing motion of a rigid body node. Typically, for nodes on a given

rigid body, the motion of no more than one node should be prescribed or unexpected

results may be obtained.

(vcm是质心的速度。vnode是指定的节点速度,是刚体的角速度，xcm是质心的当前坐标，xnode是节点的当前坐标。在规定刚体节点的运动时，需注意。通常，对于给定刚体上的节点，应规定不超过一个节点的运动，否则可能会获得无法预料的结果。)

When the RIGID option is used to prescribe rotation of a rigid body, the axis of

rotation will always be shifted such that it passes through the center-of-mass of the

rigid body. By using *PART _INERTIA or

*CONSTRAINED_NODAL_RIGID_BODY_INERTIA, one can override the

internally-calculated location of the center-of-mass.

(当使用“刚体”选项指定刚体的旋转时，旋转轴将始终移动，以使其穿过刚体的质量中心。通过使用*部分_惯性或*约束节点_刚体惯性，可以覆盖质量中心的内部计算位置。)

When the RIGID_LOCAL option is invoked, the orientation of the local coordinate

system rotates with time in accordance with rotation of the rigid body.

(调用“刚体_局部”选项时，局部坐标系的方向将根据刚体的旋转随时间旋转。)

Angular displacements are applied in an incremental fashion hence it is not possible

to correctly prescribe a successive set of rotations about multiple axes. In light of this

the command *BOUNDARY _PRESCRIBED_ORIENTATION_RIGID should be

used for the purpose of prescribing the general orientation of a rigid body.

(角位移是以增量方式应用的，因此不可能正确地规定一组围绕多个轴的连续旋转。鉴于此，应使用命令*BOUNDARY _PRESCRIBED_ORIENTATION_RIGID来规定刚体的一般方向。)