Preprocessor of the SIGMA system for training of developers of CAE application used in aerospace industry CAD systems

Аuthors

Stolyarchuk V. A.

Moscow Aviation Institute (National Research University), 4, Volokolamskoe shosse, Moscow, А-80, GSP-3, 125993, Russia

e-mail: vladimir.stolyarchuk@gmail.com

Abstract

This article describes a Preprocessor of an educational training software program intended for preparation of developers of engineering analysis systems used in CAD systems in aerospace industry. The purpose of the Preprocessor is preparation of the input data for calculations where proposed subject of calculations is a flat bar. The Preprocessor generates an optimal finite element mesh using various triangulation methods and evaluates its quality before any calculations take place.
The geometric model of the designed object is created with the help of standard primitives such as point, line, arc, circle, and is split into 8 nodal zones. The finite element mesh is generated using isoparametric coordinate method, frontal method, and several Delaunay methods. In the frontal method the density function is specified in numeric form interactively using graphical elements. In Delaunay methods first the set of support nodes of the finite element mesh is generated (in 5 different ways), then triangulation of the area is carried out using either S-Hull algorithm or the Paul Burka’s method. Results of all triangulation algorithms are attached. Additionally, the Preprocessor has a subsystem to optimize the mesh using the increasing minimum angle method and a subsystem to regulate the mesh by positioning each node in the center of gravity of the polygon. There is also a subsystem to analyze the quality of the mesh, allowing to review the full specification of the mesh with graphical highlighting of areas with high and low mesh quality. As a result, the Preprocessor is a complex tool designed for generating meshes of various types and for analyzing their characteristics. The UI of the system was designed with the purpose of training the user. It was developed using standard WinForms library. The application is using MDI (Multi Document Interface) technology allowing users to work on multiple projects. The development was done in C# programming language using .NET platform (IDE Microsoft Visual Studio 2010 Ultimate) and Tao Framework that allows .Net and Mono developers access to OpenGL and SDL.
During the use of the Preprocessor significant scientific results and lots of hands on experience were obtained.

Keywords:

CAE, finite element procedures, triangulation procedures, optimization procedures of finite element model

References

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