Electric Window

In OnScale, when any voltage conditions are applied or there is piezoelectric material for which electro-mechanical coupling is desired, the user must specify an electric window. The electric window defines the regions of the grid within which the electrostatic computation will be performed. This is required because within this region, changes are instantaneous everywhere, therefore theimplicit solver must be used. 

The user specifies the electric window using the piez wndo command. There are two ways to define the window.

Nodal Indices

ibegin iend jbegin jend kbegin kend

This defines a single electric window surrounding the area specified by the nodal indices.


auto option

This defines a single electric window surrounding all dielectric or piezoelectric materials (depending on whether option=piez or diel) so be careful with this if you have multiple piezoelectric/dielectric materials.


  1. The larger the electric window, the longer it will take to compute the electrostatic solution at each timestep. Therefore, minimising the electric window increases efficiency and gets you results quicker!
  2. More than one electric window can be declared, however, the windows must not overlap or contact each other and they will be electrically decoupled from one another.