The Meshgen-2D is a Windows application for FEM data pre-processing and generating triangular meshes. It is supposed to be used on Win95, Win98, WinNT.

The program enables:

1. Design of 2D domains having arbitrary continuous shapes bounded by poly-lines, arcs and splines.
The domain can have any number of holes, internal curves or internal points. All geometrical objects can be entered and edited graphically or numerically and coordinates of very complicated shapes can be imported from other programs (by using a text file). User interface is intuitive and easy to use.

2. Automatic generation of triangular meshes based on Delaunay triangulation.
The mesh can be refined in any node or along any curve and meshes can be very fine (the mesh size is virtually unlimited - more than 2,000,000,000 triangles). The program has a number of advanced options that enable to create very special meshes (for example a combination of very coarse and very fine mesh, stretched meshes, etc.) But mostly only one or several few commands are enough to get required simple FEM mesh. All important information about the mesh can be exported to a text file in described simple format.

Advanced options:

1. Mesh stretching.
This option enables to define the degree of mesh anisotropy in a general direction. The mesh is then deformed in the given direction, which can be desirable for problems when, for example, a different spatial step is required in the X-direction and a different one in the Y-direction.

2. Support of periodical boundary conditions.
The periodical condition is often used in fluid mechanics to simulate some "infinite" problems like flow through a turbine blade cascade etc. It can be defined on two parts of a boundary curve that are exactly the same and differ each from other just by a vector of translation. This periodical condition requires a special mesh points distribution along boundaries - each point must have a corresponding "periodical point" and their positions differ by the vector of periodical translation. If the user specifies periodical conditions, program automatically checks and corrects the mesh to satisfy these periodical conditions.

3. Mesh smoothing parameters.
There are several options to optimize mesh smoothness. In most cases predefined values of these parameters give good results so it is not necessary to change them.

4. Mesh generation step by step.
This option enables to generate FEM mesh step by step and get some special results. For example it is possible to get the minimum triangular mesh for given distribution of points on boundaries, etc.

MAIN FEATURES OF THE NEW VERSION

1. Now it is possible to generate FEM meshes of virtually unlimited sizes (more the 2,000,000,000 triangles).
2. The algorithm is faster and more stable
3. Improved user interface:

• improved object selection
• double click on an object opens a dialog with its properties
• functions "Undo" and "Redo" are available also for editing boundary points distribution and mesh generation
• many other (less important) changes

Author: M. Sejna (PC-Progress).