Capacitance of transmission line of parallel cylinders with variable radial width

This paper presents a formulation for evaluation of the capacitance of a pair of cylinders of unequal radii with variable and different width of dielectric on the cylinders. Conformal transformation using co-tangent hyperbolic function transforms the conductor boundaries to parallel plates and dielectric boundaries to curved contours. The expression for the capacitance is derived taking into account the changes in signs of the functions representing the curved contours. Numerical data on capacitance are presented.