CFD-1300: Plane 2D Meshing with Boundary Layers

In this tutorial, you will learn to generate 2D boundary layer type meshes with an arbitrary number of layers and thickness distribution in domains defined by edges. You will also generate 2D boundary layer type meshes in areas where the clearance or separation of bounding edges is not enough to accommodate the user specified nominal boundary layer thickness/number or layers.

The model file used in this exercise can be found in the file. Copy the file(s) from this directory to your working directory.

Load the CFD User Profile

  1. From the menu bar, click Preferences > User Profiles or click the Load User Profile icon, , on the Standard toolbar.
  2. Click Engineering Solutions > CFD.
  3. Click OK.

Create Nodes

  1. Click Geometry > Create > Nodes > XYZ.
  2. Enter the following for the node coordinates: Node 1: 0, 0, 0; Node 2: 0, -30, 0; Node 3: 100, 0, 0; Node 4: 100, -30, 0; Node 5: 300, 0, 0; Node 6: 300, -100, 0; Node 7: 1000, 0, 0; Node 8: 1000, -100, 0.

    Figure 1. . Nodes are created per the geometry

Create Lines

  1. Click Geometry > Create > Lines > Linear Nodes.
  2. Make your selections and click create.

    Figure 2. . Connecting the nodes to form the lines

Create the Surface

  1. Click Mesh > Surface Mesh 2D > Surface/Mesh > Planes.
  2. Select all of the lines that you created in the previous step.
  3. Click create.

    Figure 3. Created Surfaces

Generate a 2D BL Mesh

  1. Click Mesh > Surface Mesh 2D > 2D Mesh with BL.
  2. Select the 2D Smooth BL tab.
  3. Select Surfaces for generating boundary layer meshing.

    Figure 4.
  4. Set the Default selection to With BL.
    This indicates that by default 2D boundary layers will be created from all lines of selected surfaces.
    Note: If you have a few lines out of many where 2D BL needs to be generated, you can switch the default to W/o BL.
  5. Select the lines that do not require 2D BL using the W/o BL (remesh) selector, since you want the boundary layer to be imprinted on without BL edges.

    Figure 5.
    Note: If 2D BL needs to be collapsed on W/o BL edges, select it using the W/o BL (fixed) selector.
  6. Set the 2D BL parameters and mesh sizes.

    Figure 6.

    Figure 7.


In this tutorial, you generated 2D meshes with boundary layers on a complex cross section.

You obtained a high-quality mesh by allowing boundary node insertion and movement. Engineering Solutions automatically cuts back the number of layers when boundary layer collision occurs, thus producing a consistent mesh even in narrow areas. In narrow passages you can also reduce the total boundary layer thickness by starting with a smaller first layer thickness and/or a smaller growth rate.