Libre Mechanics it’s an Open Knowledge project created to offer a useful platform of information related with the development and research of Mechanical Engineering themes and similar fields, higly related with the use of Open Source and Software Libre tools. Here you will find a wide variety of projects, publications and scientific material available as references for developing their own projects, also guides and tutorials that allow you to take advantage of free software tools available today.
DOWNLOAD: Advanced CalculiX Tutorial.PDF
Usual FEA applications involve analysis where multi body assemblies are loaded to determine the contact behavior between each other, some of this data are friction, relative displacement and contact pressure. This kind of cases of study are specially complex and requires much more technological resources due to the nonlinearity characteristics of the case, where a slight change on the geometry, mesh or frontier conditions overcome on a totally different behavior.
CalculiX offers a highly custom process to control contact parameters such as, contact pressure, over closure behavior, clearance superposition and penetration; this characterized Calculix as preferred over other FEA/FEM applications on the development of especial cases where common mechanical assumptions are not sustainable such as:
- Special material coupling
- Multi phase contact
- Introduction of soft and moisturized surfaces
This technical advantage and the capacity to allow important changes on the solution central process involve the risk to inaccurate results due the lack of experience in the application of advanced parameters. For this precise tutorial it will be assumed that the user its already
familiar with the working environment of CalculiX CCX and CGX modules,
if this is not the case it is recommendable to refer first to some
beginner tutorial for example:
- Getting Started with CalculiX by Jeff Baylor
- Short Tutorial For Using CalculiX GraphiX (cgx) As Preprocessor by Guido Dhondt
- How To Install CalculiX 2.4 multi-thread under Ubuntu 11.04 and later by Libre Mechanics
This tutorial is intended to be a simple and easy way to introduce the user to the multi body contact handling on CalculiX, please notice that some scientific and technical data may not be a representation of any real life case; further contact theorical explication will be omitted in order to maintain the simplicity of this document.
As the user is probably aware by now, the document make a number of simplifying assumptions as the tutorial progressed, this is done in the interest of gaining a clearer understanding of these fundamental without getting bogged down in special details and exceptions. By no means it hast the complete history of contact handling on CalculiX, it is much broader in scope that can be presented in a single document such as this, but it is sincerely hoped that this tutorial will enable one to do a better job on the definition, solution and study of this kind of analysis.
For the ease follow of this tutorial the different used and generated files named on the different chapters are available for download, allowing the user to skip or compare any step of the tutorial by its own. Please keep in mind that any file may vary from user to user by the meshing and computational conditions, but it does not meaning this difference will represent an error of processing.
Most of the documents recurses as images and this tutorial its available at the sourceforge page