Author Topic: Global Nodal numbering Scheme  (Read 5679 times)

Son_new

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Global Nodal numbering Scheme
« on: June 12, 2013, 01:49:02 AM »
Dear All,

What is the nodal numbering scheme(first end, second end) in general that we need to obey, especially for the frame elements? IMHO there shouldn't be any procedure as long as coordinates and rotation is provided, but it seems that its not like that. Your help will be appreciated.

Regards,

 

Prof. R.L. Taylor

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Re: Global Nodal numbering Scheme
« Reply #1 on: June 12, 2013, 08:51:22 AM »
Your question is not very precise.  Generally, feap likes node numbers to be from 1 to a maximum (numnp in program), however, if nodes are not referenced by elements they are usually not used.  Thus if you only enter:

coord
  2 0 1 0.0 0.0
  4 0 1 10.0 0.0

elem
  1 0 1 2 4

all is ok.  However, feap stores nodal information for nodes 1 and 3 so memory is wasted.

Element numbers must always be from 1 to a maxiumum (numel in program).

If your questions is different please give an example of what you want to know.

Son_new

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Re: Global Nodal numbering Scheme
« Reply #2 on: June 12, 2013, 10:47:26 AM »
Sorry for not being verbose,

I mean If use below code, addressing the frame element first and end nodes in reverse order, will it cause incorrect results?
actually this is connectivity issue among elements.

Code: [Select]
coord
  2 0 1 0.0 0.0
  4 0 1 10.0 0.0
elem
  1 0 1 4 2

and what is the general approach adopted to compose the global numbering connectivity, does it really matter if element is addressed as 1 0 1 4 2   or 1 0 1 2 4 ?

Regards,
« Last Edit: June 12, 2013, 11:00:17 PM by Son_new »

Prof. R.L. Taylor

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Re: Global Nodal numbering Scheme
« Reply #3 on: June 14, 2013, 12:07:51 PM »
It should not affect the displacements you compute.  All frame elements use a coordinate transformation to make the orientation relative to global coordinates.  The easiest way to check is to solve small problems where you know the answer and check results.