Smoothing: Shift nodes on a regular surface

With this command selected nodes can be moved to regular surfaces to smooth the structure. Smoothing especially will be necessary after subdivision of macro elements with curved surfaces where these curves are located on such regular surfaces. The calculation of additional internal nodes during this subdivision is based on C⁰-Coons interpolation, which executes linear transition between opposite edges. Especially for nodes on spherical or toroidal surfaces the calculated nodes may more or less differ from the regular surface.

The regular surface must be defined within a local coordinate system. In case no local coordinate system is given the global system is used. After the definition of the surface all these nodes have to be selected which are to be moved onto this surface. With option “Maximum distance” a maximum distance may be specified. Nodes with distances from the surface greater than this value aren’t moved. Moving is done perpendicular to the specified regular surface.

Moving of nodes can also be done by command Intersection, which does a translation of nodes along a vector and so an intersection of 2 regular surfaces can be achieved.

Following dialog shows the available options:

Regular surface

Plane: Any of x,y,z values can be set as a constant value in respect to a given coordinate system i.e. only the value in this direction is changed to the given value. The relevant value must be provided in the input field.

Circular cylinder: Radius must be given in the input field. Z-axis of the given coordinate system will be chosen as the axis of the cylinder.

Sphere: The radius of the sphere must be given in the input field. Basis of the given coordinate system will be chosen as the center of the sphere.

Torus: The radius of the toroidal surface must be given in the input field. Nodes P1 and P2 of the given coordinate system define the radius of the torus. This coordinate system must be defined as a toroidal system.

Cone: Two ID’s of nodes lying on the cone surface must be given. If button “Graphically” is pressed, the 2 nodes can be selected graphically. The z-axis of the selected coordinate system will be used as the cone axis. The displacement of the nodes is perpendicular to the cone surface.

Coor System: The ID of a previously defined coordinate system must be given. The list box shows all currently available systems. ID 0 is for global coordinate system.

Input field: Parameters (for example radius, node ID’s) must be given within this input field.

Maximum distance: Maximum value for the distance a node can be moved may be given.

Node selection / element selection

Select nodes to be translated or select elements where all nodes of selected elements are considered.

Undo

Pressing this button, the latest displacement is made undone.