Field behaviour at a triple junction in composite dielectric arrangements

The author examines the field behaviour at and near various points of contact between a solid dielectric and a conductor. The topics discussed include analytical expressions and numerically calculated results of field strength as well as their potential practical applications. The effect of conductivity is explained in some cases. There are principally three contact conditions depending on the contact angle; 90, 0 to 90, and 0°. The contact angle between 0 and 90° results in a field concentration of K×l^m near a contact point where l is the distance from the point. In the case of zero contact angle, where a solid dielectric and a conductor are both rounded or planar, a simple mathematical function expresses the effect of relative permittivity on the field concentration at the contact