PADDER is an algorithm that creates a set of particules called a "discrete mesh". The particules are characterized by a location in space and a weight that can be considered as the radius of a sphere whose center is the location of the particule.
Discrete meshes are typically used to modelize civil components in rapid dynamic computation problems (seisms, chocs). These components consists in concrete parts embedding steal bares for reinforcement. These parts are input to the algorithm as standard finite elements meshes. The cells of theses meshes drive the location and sizing of particules.
In the med representation, a discrete mesh is described as MED_BALL elements. A MED_BALL element is defined by a location and a radius.
The PADDER algoritm is integrated in the module SMESH as a SALOME plugin. This section illustrates how to use this plugin to create a discrete mesh.
In this example, we suppose that two standard meshes (Finite Elements Meshes) have been created and publish in the study to modelize the concrete part (here with the name "concrete") and the steal bars part (here with the name "ferrail"):
The PADDER plugin can be invoked from the SMESH plugins menu, as illustrated on the figure below:
When you clic on the "PADDER mesher" item, the graphical interface of the PADDER plugin appears:
This interface invites you to specify input data by pressing the button "Input". This command opens the Input dialog box to specify the list of meshes and the type of the selected meshes (to be choosen between "concrete" or "steelbar" using the combobox on the right side of the input line):
In the figure below, the mesh with name "concrete" has been selected in the study and added in the list of input file as a "concrete mesh". You have to input the mesh in the dialog using the rounded arrow icon, then specify a group name (the name of the group of MED_BALL created for this mesh in the resulting mesh), and finnaly clic on the "Add" icon:
Then, the mesh with name "ferrail" is selected and added to the list as a "steelbar mesh":
The input dialog box can be validated toreturn to the main plugin interface. The "Compute" button is now enable, indicating that the problem is ready to be computed:
The command "Compute" start the job. The progression can be requested using the command "Refresh". In the figure below, the job is still running:
Finally, the job is finished and the result is ready to be published in the SALOME study:
Clic on the command "Publish" to explicitly import the resulting med file in SMESH and published the resulting mesh in the SALOME study:
Note that this mesh contains one group for each of the input mesh. A group with the name specified in the input dialog has been defined for the set of MED_BALL created from the corresponding input mesh:
The configuration of the plugin consists in specifying the location of the padder executable program for each of the SALOME resource (at least for the localhost resource). This specification is done in the file padder.cfg, located in the plugin installation folder (i.e. <SMESH_ROOT_DIR>/plugins):