Hello Ulrich,
Thank you for your reply. You can find the related section in the folowing link
https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v232/en/flu_th/flu_mhd_sec_electric_potential.html
It is the MHD module part of the theory guide.
Which way do you thin is the best to define charge density for particle tracking?
Best regards,