dear sir,
i am new to caeser. i want to know why we use connecting node in caeser?? what is the difference bw normal node and the connecting node?? i have read the definition of the connecting node in caeser guide but i coudn't relate it to practicle application. please clarify my doubt..

Dear shrav

Please type +connecting+node
in the search box located at the top right corner of the forum page and you will find discussions on connecting node and its applications.

regards
Siddharth.

Connective node means a node point which is related to other node no.

Like we model node 40 then node 50 then node 60 it makes continuous pipe.
Instead if I make 40 to 50 pipe then 50 connective node 51 with anchor then 51 to 60 another pipe . Both the above makes the same thing.

But If in connective node instead anchor we make Y support it will be different.

Connective node means there are two node no in same global co ordinate. Now we have choice to make relation between that two node no 50 & 51.

If we make connective node with Y support means there will not be any relative movement between them in Y direction but both the point are free to move with respect to other in Z ,X Ry,Rz & Rx direction

Conneting nodes does not necessarily mean that two nodes are at same pt. in space.
It simply means that the two points are connected in the specified degree of freedom ( say ANC, X, Y, Z etc) by the specified stiffness [ if default stiffness is used then the node-C-Node are not having any relative desplacement in the connected DOF but can have relative displacement in the non connected DOFs. If however non rigid stiffness has been used, the node, C-node can have relative displacement even in the connected DOF(s)].

A simpler way to look is like this: A point w/o C-node is also having a C-node which is immovable in space say , ground . For a node having a C-node the point is moving and not immovable in space.

Suppose a pipe is supported from ground , this is a case of " no C-node".

Similarly if a pipe is supported from a pipe support clip welded to a vessel that point is not immovable like ground.

Mathematically C-node is an application of an FEA concept of " Multi Point Constraint".

There are enough examples in CAESAR II manuals to explain this concept.

Thanks Anindya for your response.
I was trying the idea in caesar
“Connecting nodes does not necessarily mean that two nodes are at same pt. in space.”

When ever I am trying to connect two node with connecting node where there are global difference of co ordinate , caesar by default pulling both the node point in same location over-riding there previous two different global co ordinate.
In a big model also when ever I am trying to connect a node point with other node point which are within the model but in different location then caesar break the model & can not run, it is showing dimensional error.
That means what I feel caesar model understand connecting node in same global co ordinate only.
Please correct me if I miss something in my understanding.
In case of finite element analysis I do not any idea about connecting node behavior but I feel it will be very difficult for piping model to behave properly when we try to relate two different location node point .
Thanks Anindya once again for your good suggestion on different topic in this forum & personal help.

The idea behind the CNODE (connecting node) is "an association of degrees of freedom". Take that phrase and think about it.

Then visualize a "ball and socket connection", like your shoulder. This is an example of a CNODE where the associated degrees of freedom are "X", "Y", and "Z".

Typically, the CNODEs are at the same location in space - such as with your shoulder. However, there are instances where this isn't true, so you can flip the setting of the Configuration Directive CONNECT_GEOMETRY_THRU_CNODES. Note, this setting applies to the whole model, you can't have it set one way for just a part of the model.

Thanks Richard.
Got the Idea.

thank you all for your kind reply.. we are doing a project in which support is defined in node and displacements are defined at connecting node. if we define both support and node at same point it is showing error,why it so?? does the reactions differ in connecting node and the node to which it is connected.??

A support is a "boundary condition", a displacement is a "boundary condition". So numerically a support and a displacement are the same thing. A support can be thought of as a displacement of zero magnitude. For example, a "Y" support could be modeled as this displacement vector: (free, 0.0, free, free, free, free).

CAESAR II complains if you try to over-specify a boundary condition (so don't do it). If you need to specify a displacement, remove the support and properly specify the displacement vector(s).

Supports simplfy the input:
- It is much easier to specify a "Y" support than the above example displacement vector.
- You can't specify a "+Y" using a displacement vector.
- You can't specify a "gap" using a displacement vector.

Supports and Displacements each serve their own purpose to simplify modeling. However, they are both boundary conditions that restrict movement in specified degrees of freedom.

thank you sir..

sir , we give some displacemnts at cnode.. will the reactions at cnode be reflected at node to which it is connected?? for example let us assume a node 10 i will give here just a rest and in its connecting node 11 i will give here displacement in x,y,z directions then the reactions at node and cnode should differ .. is it right ,sir..

If a given degree of freedom is associated (between a node and cnode) with a rigid stiffness, then the load will be the same on the node and the cnode.