What to do if you get 'No electrode node defined' Error in OnScale?

Question:

I am using OnScale to check shear stress on top of my transducer.

I kept getting error called ' No electrode node defined '. My model structure changes depending on frequency and the error comes out if drive frequency is above 4MHz.

Where does that come from?

Answer:

The ' No electrode node defined ' error happens when you had an electrode defined, but then you changed the geometry or the mesh size.

The previous definition of the electrode region cannot find any node in the new changed geometry or mesh.

 no_nodes_defined_electrode.png

In OnScale, electrodes are created by a certain region in space (a surface) which is defined by keypoints. The nodes located within the electrode definition region are automatically assigned a voltage load.

You need to have some nodes within that surface so that when the electrode is created it can associate an electrical load to those nodes.

If you change the mesh size and the electrode definition surface falls on a region with no nodes defined, it will tell you there is no nodes defined.

The position of the electrode does not automatically change if the model has not been configured in a parametric way.

 Try to visualize the electrodes using the following code

(place it after the piez command)

grph 
   Type standard
   Line on
   Plot piez
   end

This will plot only the electrodes. Make sure they exist where you want them to be located!

Use “plot matr piez” to plot both model and electrodes.

 Check that you have some nodes defined for both electrodes.

 If there are no nodes, you need to change the grid to make sure you have some keypoints defined at the position of the electrodes

Related Question:

If the frequency of my transducer changes from 1 MHz to 10 MHz, should I change also the mesh size?