Tutorial revisited

As Grid has evolved since the tutorial was written, there is now an easier way to create the channel:

  1. Click and create a new grid with dimension 2.5x0.32 consisting of 12x4 quads.

    New unit grid.

  2. Choose the "Create Clockwise Circle" mode and create a circle approximately at (0.5, 0.2). Place the mouse cursor above the center of the circle and press Return. If a list of items pops up, choose the Point in the list. In the dialog box enter the exact coordinates for the circle center and click Ok. Now move the mouse cursor atop the circle and press Return once more. Choose the circle from the list and change the radius to 0.05.

    Channel with circle

  3. Choose the "Selection" mode and make sure inner node and boundary node are selectable , .
  4. One by one, select a column of nodes and arrange them on the sides of the circle. Use the middle mouse button to move the selected points. Hold Control while doing so to restrict movement to the x-axis. Try to arrange the nodes around the circle as shown in the image below.

    Channel with circle, now adjusted

  5. Now select the inner node near the circle center (not the circle center itself) and choose Delete selected items from the context menu.

    Channel with hole

  6. Now we have to put the inner nodes on the circle boundary. Select the inner nodes near the circle and open the context menu. Choose Operations/Inner to BoundaryNode and the channel is complete.

    Completed channel