.. _quickstart_meshing_webUI:
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Automated Meshing with the WebUI
*********************************

After uploading a CAD geometry into a new project (see the :ref:`previous Quick Start tutorial <quick_start_geometry>`), the next step is to mesh it. This tutorial uses the **beta mesher** to generate both the surface mesh and the volume mesh from the geometry.

Turning on the beta mesher
==========================

The mesher is chosen per project in the **Project settings** drawer. A new project uses the mesher set as your account's **Default mesher**, which is the **Legacy mesher** unless you have changed it.

#. Open the project created in the :ref:`previous tutorial <quick_start_geometry>`.
#. Click the gear (**Settings**) button in the top bar and select **Project settings**.
#. On the **Run settings** tab, turn on **Beta mesher**. Leave **GeometryAI** off: while it is on, the project uses the GeometryAI mesher and the **Beta mesher** toggle cannot be changed.
#. Close the drawer.

The toggle can only be changed while you are editing a draft run, which is the state a newly created project opens in. See :doc:`/gui_guide/01.introduction/07.project-settings` for the other settings in this drawer.

.. figure:: Figures/beta_mesher_toggle.png
   :width: 95%
   :align: center

   *Turning on the beta mesher in Project settings.*

.. tip::

   To start every new project with the beta mesher, set **Default mesher** to **Beta mesher** in your account preferences (see :doc:`/gui_guide/06.account-settings/01.preferences`). The preference is applied the first time you open a new geometry project.

Grouping the faces
==================

The faces of the eVTOL are grouped in the .csm file through their ``groupName`` attribute. The mesh keeps one boundary per face group, so choose the grouping before meshing.

In the **Entities** panel on the right, the **Faces** entry is grouped by ``faceId`` by default, one entry per CAD face. Set the grouping selector next to **Faces** to ``groupName`` and confirm. **Faces** now lists the seven groups of the eVTOL.

.. figure:: Figures/faces_grouping.png
   :width: 60%
   :align: center

   *Grouping the faces by groupName.*

.. note::

   Switching the grouping clears what is already assigned to the faces, such as boundary conditions or refinements, so set it first.

Setting the mesh parameters
===========================

The mesh settings are in the **Mesh** section of the **Simulation** tab on the left. The **Farfield** keeps its default **Automated farfield** type, so nothing needs to change there for this tutorial.

Click **Mesh parameters** to open its panel. Two fields have no default and must be filled in before meshing:

* **Surface max edge length**: enter ``0.1`` m.
* **Boundary layer first layer thickness**: enter ``1e-6`` m.

Keep the defaults for the other fields, including a **Curvature resolution angle** of 12 degrees. Each parameter is described in :doc:`/gui_guide/02.simulation-setup/02.mesh/02.mesh-parameters`, and :ref:`our meshing guidelines <knowledge_base_meshing>` help choose values for your own geometries.

.. figure:: Figures/mesh_parameters_beta.png
   :width: 95%
   :align: center

   *Required mesh parameters for the eVTOL.*

.. note::

   The beta mesher does not offer the **Surface edge refinement** used by the legacy mesher, so the leading-edge refinement from earlier versions of this tutorial is not needed. The refinements that the beta mesher supports are listed in :doc:`/gui_guide/02.simulation-setup/02.mesh/06.refinements/README`.

Running the meshers
===================

With the required settings in place, launch the meshing tool chain from the **Run** button at the top right. The main **Run** button runs the whole simulation, so use the arrow next to it instead. Its menu offers **Up to surface mesh** and **Up to volume mesh**.

Select **Up to volume mesh**. In the **Preview** window, name your run and click **Run up to volume mesh**. The surface mesh is generated first, then the volume mesh.

.. figure:: Figures/run_volume_mesh.png
   :width: 95%
   :align: center

   *Launching the surface and volume meshers.*

Inspecting the mesh
===================

Once a mesh is available, click **Mesh** in the view selector at the top of the viewer and select **Mesh (Surface)** or **Mesh (Volume)**. The viewer first loads a low-resolution preview. To see the mesh elements, click **Low res** and select **High resolution**.

.. figure:: Figures/mesh_view.png
   :width: 95%
   :align: center

   *Viewing the generated mesh.*

To navigate the view:

* Hold the right mouse button and drag to pan.
* Scroll the mouse wheel to zoom in and out.
* Hold the left mouse button and drag to rotate.
* Click a face, edge or corner of the **Rotation cube** to snap to that view.

The full list of mouse and keyboard controls is in :doc:`/gui_guide/01.introduction/06.shortcuts`.

.. figure:: Figures/view_cube.png
   :width: 95%
   :align: center

   *Using the rotation cube to align the view.*

Congratulations, you now have a mesh that is ready to run simulations on. You can now proceed to the next quick start tutorial on :ref:`launching a case <quickstart_case_launching_webUI>`.