patran& nastran MPC 说明

fzh03120110

MPC Type	Analysis Type	Description
Explicit	Structural	Creates an  explicit MPC between a dependent degree of freedom and one or more  independent degrees of freedom. The dependent term consists of a node ID and  a degree of freedom, while an independent term consists of a coefficient, a  node ID, and a degree of freedom. An unlimited number of independent terms  can be specified, while only one dependent term can be specified. The  constant term is not allowed in MSC.Nastran.
Linea r Surf-Vol	Structural	Creates an  RSSCON type MPC between a dependent node on a linear 2D plate element and two  independent nodes on a linear 3D solid element to connect the plate element  to the solid element. One dependent and two independent terms can be  specified. Each term consists of a single node.
Rigid (Fixed)	Structural	Creates a  rigid MPC between one independent node and one or more dependent nodes in  which all six structural degrees of freedom are rigidly attached to each  other. An unlimited number of dependent terms can be specified, while only  one independent term can be specified. Each term consists of a single node.  There is no constant term for this MPC type.
RBAR	Structural	Creates an  RBAR element, which defines a rigid bar  between two nodes. Up to two dependent and two independent terms can be  specified. Each term consists of a node and a list of degrees of freedom. The  nodes specified in the two dependent terms must be the same as the nodes  specified in the two independent terms. Any combination of the degrees of  freedom of the two nodes can be specified as independent as long as the total  number of independent degrees of freedom adds up to six. There is no constant  term for this MPC type.
RBE1	Structural	Creates an  RBE1 element, which defines a rigid body connected to an arbitrary number of  nodes. An arbitrary number of dependent terms can be specified. Each term  consists of a node and a list of degrees of freedom. Any number of  independent terms can be specified as long as the total number of degrees of  freedom specified in all of the independent terms adds up to six. Since at  least one degree of freedom must be specified for each term there is no way  the user can create more that six independent terms. There is no constant  term for this MPC type.
RBE2	Structural	Creates an  RBE2 element, which defines a rigid body between an arbitrary number of  nodes. Although the user can only specify one dependent term, an arbitrary  number of nodes can be associated to this term. The user is also prompted to  associate a list of degrees of freedom to this term. A single independent term  can be specified, which consists of a single node. There is no constant term  for this MPC type.
RBE3	Structural	Creates an  RBE3 element, which defines the motion of a reference node as the weighted  average of the motions of a set of nodes. An arbitrary number of dependent  terms can be specified, each term consisting of a node and a list of degrees  of freedom. The first dependent term is used to define the reference node.  The other dependent terms define additional node/degrees of freedom, which  are added to the m-set. An arbitrary number of independent terms can also be  specified. Each independent term consists of a constant coefficient  (weighting factor), a node, and a list of degrees of freedom. There is no  constant term for this MPC type.
RROD	Structural	Creates an  RROD element, which defines a pinned rod between two nodes that is rigid in  extension. One dependent term is specified, which consists of a node and a  single translational degree of freedom. One independent term is specified,  which consists of a single node. There is no constant term for this MPC type.
RSPLINE	Structural	Creates an  RSPLINE element, which interpolates the displacements of a set of independent  nodes to define the displacements at a set of dependent nodes using elastic  beam equations. An arbitrary number of dependent terms can be specified. Each  dependent term consists of a node, a list of degrees of freedom, and a  sequence number. An arbitrary number of independent nodes (minimum of two)  can be specified. Each independent term consists of a node and a sequence  number. The sequence number is used to order the dependent and independent terms  with respect to each other. The only restriction is that the first and the  last terms in the sequence must be independent terms. A constant term, called  D/L Ratio, must also be specified.
RTRPLT	Structural	Creates an  RTRPLT element, which defines a rigid triangular plate between three nodes.  Up to three dependent and three independent terms can be specified. Each term  consists of a node and a list of degrees of freedom. The nodes specified in  the three dependent terms must be the same as the nodes specified in the  three independent terms. Any combination of the degrees of freedom of the  three nodes can be specified as independent as long as the total number of  independent degrees of freedom adds up to six. There is no constant term for  this MPC type.
Cyclic Symmetry	Structural	Describes  cyclic symmetry boundary conditions for a segment of the model. If a cyclic  symmetry solution sequence is chosen, such as “SOL 114,” then CYJOIN, CYAX  and CYSYM entries are created. If a solution sequence that is not explicitly  cyclic symmetric is chosen, such as “SOL 101,” MPC and SPC cards are created.  Be careful, for this option automatically alters the analysis coordinate  references of the nodes involved. This could erroneously change the meaning  of previously applied load and boundary conditions, as well as element  properties.
Sliding Surface	Structural	Describes the  boundary conditions of sliding surfaces, such as pipe sleeves. These boundary  conditions are written to the NASTRAN input file as explicit MPCs. Be  careful, for this option automatically redefines the analysis coordinate  references of all affected nodes. This could erroneously alter the meaning of  previously applied load and boundary conditions, as well as element  properties.