Dear Rajeev,
It cannot be explained in simple terms.If you have had a formal course on FEM, you should be knowing about how stiffness matrix is generated in FEM or how boundary conditions are modelled. The only thing which you may not know is how the elbow elements function.If you did not have any formal course on FEM, I would advise you to read the book by Cook, Malkus and Plesha on this subject and you will find answers to most of your queries there.Regarding elbow elements, read manual of any standard general purpose finite element code like ABAQUS for eg.It tells a lot about those elements.There is a paper by Bathe and Almeida on elbow elements. However behaviour of elbows can also be simulated by using shell elements , something which is done by FE Codes like FEPipe/NozzlePro to generate SIF and Flexibility factors.
Regards
Edited by anindya stress (04/04/10 06:22 AM)
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anindya