PREFLU offers easy definition geometrical entities or geometry modification.
Parameters can be simple numerical values or complex arithmetical formulas and used to define node coordinates and circle radii.
Figures 1 and 2 illustrate the modified geometry parameters, which accurately describe the geometry of a motor's rotor teeth.
When a parameter's value is changed, PREFLU automatically adjusts lines, regions, and meshes defined by that parameter. Manual redefinition is not necessary.
Another parameter application is point duplication, making it easier to describe repetitive geometry sections.
Figure 3 shows the initial geometry of a rotor tooth. Figure 4 shows how point duplication and parameter modification allow recreation of rotor teeth for motor design.
Various geometry sections can be defined as different regions. PREFLU offers four different types of regions:
These regions make it possible to define FLUX2D models for magnetic, electrostatic, and electric conduction problems.
You can represent an open boundary by using an Infinite region. This eliminates the need to create unnecessarily large meshes.
Shell regions in PREFLU are used to describe ATILA geometries. These shell regions allow ATILA to model fluid/solid interfaces and fluid damping regions. Shell regions are used in FLUX2D to represent certain boundary conditions.
When using PREFLU, it is not always necessary to include some regions in the problems domain. For example, in electrostatics the conductor is not needed for computation. You can exclude these regions from the mesh by defining Hole regions.
In PREFLU, you can assign a different set of physical properties to each region of the model. Figure 5 illustrates the regions of a motor. Each of these regions is defined with different physical properties.
PREFLU features automatic and assisted mesh generators. These generators can be coupled to create a more precise mesh. They generate second-order triangular or quadrilateral elements
The assisted mesh generator can be used to locally control the mesh density, or to reduce the number of elements used. This generator uses predefined parameterized and non-parameterized elements to subdivide a mesh. Figure 6 shows how the assisted mesh generator is used to describe the mesh of the magnet regions in our motor. Quadrilateral elements are used in the magnets to create a uniform mesh.
Using the automatic mesh generator, based on the Delaunay triangulation method, is a fast and efficient way to create a mesh for your model. The mesh density is determined by the position and number of nodes that are placed on the lines of your geometry. If the mesh density is inconsistent, PREFLU automatically creates nodes to compensate. You control the node distribution on the lines of the geometry. This means that you control the density of your mesh. Figure 7 illustrates the automatic mesh node placement on the lines of the motor's geometry.
PREFLU allows you to couple both mesh generators to create meshes that are well adapted to your model. This coupling allows you to locally control the mesh density to obtain more accurate results. Figure 8 illustrates how the assisted mesh regions in Figure 6 are coupled with the automatic mesh regions in Figure 7 to create an accurate mesh of the motor.
PREFLU is an effective tool for creating geometries and Finite Element Models. These models are well adapted to electromagnetic and thermal applications, including linear and rotating motion. As FLUX2D'S preprocessor, PREFLU allows you to define models for computing magnetic, electric, and thermal fields. When using PREFLU as ATILA's preprocessor you can model problems which include fluid/solid interfaces and fluid damping regions.