elements at the intersection of Cartesian cells with the geometrical
boundary.
-\image html cartesian3D_sphere.png "A shpere meshed by Body Fitting algorithm"
+\image html cartesian3D_sphere.png "A sphere meshed by Body Fitting algorithm"
The meshing algorithm is as follows.
<ol>
</li>
</ol>
To apply this algorithm when you define your mesh, select <b>Body
- Fitting</b> in the list of 3D algorithms and click <em> "Add
- Hypothesis" </em> button and <em>"Body Fitting Parameters"</em>" menu
- item. Dialog of <b>Body Fitting Parameters
- hypothesis</b> will appear.
+ Fitting</b> in the list of 3D algorithms and add <b>Body Fitting
+ Parameters</b> hypothesis. The following dialog will appear:
<br>
\anchor cartesian_hyp_anchor
This dialog allows to define
<ul>
-<li>\b Name of the algorithm </li>
-<li> Minimal size of a cell truncated by the geometry boundary. If the
- size of a truncated grid cell is \b Threshold times less than a
- initial cell size, then a mesh element is not created. </li>
-<li> Cartesian structured grid. Each grid axis is defined
- individually. <b> Definition mode </b> chooses a way of grid
- definition: <ul>
- <li> You can specify the \b Coordinates of grid nodes. \b Insert button
- inserts a node at distance \b Step (negative or positive) from a
- selected node. \b Delete button removes a selected node. Double
- click on a coordinate in the list enables its edition. A grid
- defined by \b Coordinates should enclose the geometry, else the
- algorithm will fail. </li>
- <li> You can define the \b Spacing of a grid as an algebraic formula
- <em>f(t)</em> where \a t is a position along a grid axis
- normalized at [0.0,1.0]. The whole range of geometry can be
- divided into sub-ranges with their own spacing formulas to apply;
- \a t varies between 0.0 and 1.0 within each sub-range. \b Insert button
- divides a selected range into two ones. \b Delete button adds the
- selected sub-range to the previous one. Double click on a range in
- the list enables edition of its right boundary. Double click on a
- function in the list enables its edition.
- </li> </ul>
-</li>
-</ul>
+ <li>\b Name of the algorithm. </li>
+ <li> Minimal size of a cell truncated by the geometry boundary. If the
+ size of a truncated grid cell is \b Threshold times less than a
+ initial cell size, then a mesh element is not created. </li>
+ <li> <b> Implement Edges </b> check-box activates incorporation of
+ geometrical edges in the mesh.
+
+\image html cartesian_implement_edge.png "Implement Edges switched off to the left and on to the right"
+
+ <li> <b>Definition mode</b> allows choosing how Cartesian structured
+ grid is defined. Location of nodes along each grid axis is defined
+ individually:
+ <ul>
+ <li> You can specify the \b Coordinates of grid nodes. \b Insert button
+ inserts a node at \b Step distance (negative or positive) from the
+ selected node. \b Delete button removes the selected node. Double
+ click on a coordinate in the list enables its edition.
+ \b Note that node coordinates are measured along directions of
+ axes that can differ from the directions of the Global Coordinate
+ System.</li>
+ <li> You can define the \b Spacing of a grid as an algebraic formula
+ <em>f(t)</em> where \a t is a position along a grid axis
+ normalized at [0.0,1.0]. <em>f(t)</em> must be non-negative
+ at 0. <= \a t <= 1. The whole extent of geometry can be
+ divided into ranges with their own spacing formulas to apply;
+ \a t varies between 0.0 and 1.0 within each \b Range. \b Insert button
+ divides a selected range into two. \b Delete button adds the
+ selected sub-range to the previous one. Double click on a range in
+ the list enables edition of its right boundary. Double click on a
+ function in the list enables its edition.
+ </li> </ul>
+ </li>
+
+ <li> <b> Fixed Point</b> group allows defining an exact location of
+ a grid node in the direction defined by spacing. The following cases
+ are possible:
+ <ul>
+ <li>If all three directions are defined by spacing, there will
+ be a mesh node at the <b> Fixed Point</b>. </li>
+ <li>If two directions are defined by spacing, there will be at
+ least a link between mesh nodes passing through the <b> Fixed
+ Point</b>.</li>
+ <li> If only one direction is defined by spacing, there will be
+ at least an element facet passing through the <b> Fixed
+ Point</b>.</li>
+ <li>If no directions are defined by spacing, <b> Fixed Point</b>
+ is disabled.</li>
+ </ul>
+ </li>
+
+ <li> <b> Directions of Axes</b> group allows setting the directions of grid axes.
+ <ul>
+ <li>If <b> Orthogonal Axes </b> check-box is activated the
+ axes remain orthogonal during their modification. </li>
+ <li> Selection buttons enable snapping corresponding axes to
+ direction of a geometrical edge selected in the Object
+ Browser. Edge direction is defined by coordinates of its end
+ points.</li>
+ <li><b> Optimal Axes</b> button runs an algorithm that tries to
+ set the axes to maximize the number of generated hexahedra.</li>
+ <li><b> Reset </b> button returns the axes in a default position
+ parallel to the axes of the Global Coordinate System.</li>
+ </ul>
+ </li>
+ </ul>
<br>
-<b>See Also</b> a sample TUI Script of a
-\ref tui_cartesian_algo "Usage of Body Fitting algorithm".
+<b>See Also</b> a sample TUI Script of a
+\ref tui_cartesian_algo "Usage of Body Fitting algorithm".
*/