Computing the Effect of Fringing Fields on Capacitance
Application ID: 12605
A typical capacitor is composed of two conductive objects with a dielectric in between them. A voltage difference applied between these objects results in an electric field between them. This electric field exists not just directly between the conductive objects, but extends some distance away, this is known as a fringing field. To accurately predict the capacitance of a capacitor, the domain used to model the fringing field must be sufficiently large, and the appropriate boundary conditions must be used. Here, a parallel plate capacitor in air is modeled, and the size of the air domain is studied. The choice of boundary condition is also addressed.
This model example illustrates applications of this type that would nominally be built using the following products:AC/DC Module
however, additional products may be required to completely define and model it. Furthermore, this example may also be defined and modeled using components from the following product combinations:
- COMSOL Multiphysics® and
- either the AC/DC Module, MEMS Module, Plasma Module, or Semiconductor Module
The combination of COMSOL® products required to model your application depends on several factors and may include boundary conditions, material properties, physics interfaces, and part libraries. Particular functionality may be common to several products. To determine the right combination of products for your modeling needs, review the Tabela de Especificações and make use of a free evaluation license. The COMSOL Sales and Support teams are available for answering any questions you may have regarding this.