User Forum of Software BASEMENT

gunsonj

User

Registered: 2015-10-19

Posts: 1

building an ocean model mesh whose element area is dependent on depth

I am using BASEMESH with QGIS to construct a finite-element grid for
use with the ocean wave model SWAN (SWAN can use the triangle
output files to make an unstructured grid).

Is there a way of generating the mesh such that the element area
is a simple function of the water depth ? 
See for example, the two plots in the middle of the page at
http://swanmodel.sourceforge.net/unswan/unswan.htm

Regards,

Jim

qtheiler

User

Registered: 2015-07-30

Posts: 60

Re: building an ocean model mesh whose element area is dependent on depth

Hi,

You can try to increase the number of vertices at the border coast.  This means that you line must have more vertices at this border. This will automatically increase the mesh definition.

Cheers.

Sam

Developer

From: VAW - ETH Zurich

Registered: 2014-09-04

Posts: 46

Website

Re: building an ocean model mesh whose element area is dependent on depth

this cannot be done automatically within BASEmesh.

But you can manually add region points that define the maximum element size (see Quality meshing in BASEmesh):
- define regions that are enclosed by breaklines e.g. region with water depth larger than 20m.
- put a point inside that region with a field containing the maximum element area within that region (you can choose this value freely, e.g. your function with argument 20)

your result should then look quite similar to the plots you posted.

have fun, cheers