Category Archives: FEM – Analysis

Finite Element Method
The finite element method (FEM) is a numerical technique for finding approximate solutions to boundary value problems for differential equations. It uses variational methods (the calculus of variations) to minimize an error function and produce a stable solution. Analogous to the idea that connecting many tiny straight lines can approximate a larger circle, FEM encompasses all the methods for connecting many simple element equations over many small subdomains, named finite elements, to approximate a more complex equation over a larger domain.

Fastener modelling in Nastran

This way of modelling presented in this post is one of most used, as it is simple and sufficiently accurate. For the fastener modelling generally is used a Spring type element (CBUSH), and it should be done as Mesh-indipendent, like a … Continue reading

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Linear Buckling Analysis – SOL 105

Theoretical Background Buckling analysis assesses the stability characteristics dictating the integrity limit of a structure. Let us start with a linear equation of motion for a preloaded structure: where M,C, K and  Kd are mass, viscous damping, material and differential stiffness … Continue reading

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Problems with Large XDB or OP2

If you are constantly having to work with large models and larger output in XDB format, MSC Nastran has come out with a good solution. A common fatal message encoutered while writting out large size xdb files is UFM 6062(DBC). … Continue reading

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