## Tag Archives: NASTRAN

## Static Condensation – FEM Analysis

Background Theory With “condensation” is indicated a procedure adopted for the structural analysis to carry out a matrix of stiffness and load boundary conditions of a detailed finite model (DFEM), starting from a raw global finite model (GFEM). The DFEM … Continue reading

## Contact simulation with MSC/Nastran

Linear Gap The linear GAP is the simpliest contact form used in Nastran simulations. Linear GAP can solve a large class of problems like hole bearing, heel-toe interaction, fitting contacts. Linear, therefore does not include frition, large displacements, and material … Continue reading

## Non linear Buckling with FEM approach

Buckling analysis assesses the stability characteristics of a structure. An accurate solution to a buckling problem requires more efforts than just following a numerical procedure, there are a number of factors to consider before a buckling solution can be accepted … Continue reading

## Nastran run in batch mode

Sometimes is necessary to perform several Nastran runs, and by running one by one could be necessary a lot of time. Hereafter are illustrated two methods to speed up these operations. There is an effective method to perform this operation … Continue reading

## Nastran launch commands

The Nastran solver is executed usually by command line like „nastran“. Generally it could be with different name, due to the needs to specify the version of solver. The format nastran command is: nastran2012 input_file keyword1 = value1 keyword2 … Continue reading

## Random Vibration Analysis – Nastran SOL 111

Introduction Random vibration is motion which is non-deterministic, meaning that future behavior cannot be precisely predicted, and it is a characteristic of the input or excitation. To specific a random vibration is usually is used the ASD (acceleration spectral density). … Continue reading

## 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