.. _tutorials:

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Tutorials
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This tutorial aims at giving important steps of the use of « Bloc Fissure ». Those steps are the standard procedure that the user should apply to avoid « Bloc Fissure » failure and unexpected problem in the modelisation afterwards.

First, the user should ask himself if its case is compatible with « Bloc Fissure ». See the section on :ref:`limitations <recommendations>`.

1) Convert elements from quadratic to linear

Mesh Module: Modification > Convert to/from quadratic

2) Change the orientation of all faces to set them to outgoing

Mesh Module: Modification > Reorient faces

3) Verify that the crack exceeds everywhere from the structure. If it's not the case, move or extend the crack geometry.

4) Verify that the crack front edges don't stop right at the Box surface.

**Here are some advices :**

*To move the crack:*

GEOM Module: Operations > Transformation > Translation

*First way to extend the crack geometry in GEOM module:*
  - Operations > Explode: Choose the crack geometry and explode into Edges
  - Operation > Transformations > Extension: extend the length of the crack edges
  - Rebuild edges to get a closed group of edges exceeding from the structure
  - New Entity > Build > Wire: Create a wire from the edges
  - New Entity > Build > Face: Create a face from the wire
  - Get the new crack front edge number

+-----------------------------------+-----------------------------------+-----------------------------------+-----------------------------------+
| .. image:: images/tutorial_1.png  | .. image:: images/tutorial_2.png  | .. image:: images/tutorial_3.png  | .. image:: images/tutorial_4.png  |
|    :height: 200                   |    :height: 200                   |    :height: 200                   |    :height: 200                   |
|    :align: center                 |    :align: center                 |    :align: center                 |    :align: center                 |
+-----------------------------------+-----------------------------------+-----------------------------------+-----------------------------------+
|    Initial bad crack geometry     |   Explode face into edges         |  Extend front edge and            |  Rebuild crack face               |
|                                   |                                   |  rebuild wire                     |                                   |
+-----------------------------------+-----------------------------------+-----------------------------------+-----------------------------------+

*second way to extend the crack geometry in GEOM module:*
  - Create new surfaces linked to the original crack geometry
  - Fuse the surfaces to get an extended crack

5) Execute the « Bloc Fissure » script and check that it ended successfully.

6) Reorient faces to outgoing normal

7) Rebuild groups impacted by crack insertion

8) Export the cracked mesh










