Tapered Wires

A tapered wire is a wire whose radius varies along its length. Because the change in radius occurs in discrete increments, it is also known as a stepped-radius wire. Tapered wires always have a circular cross section, and the radius typically changes linearly in defined steps—resulting in a wire with sections of constant radius, as illustrated in Fig. 1.

To draw a tapered wire, go to Draw > Tapered Wire in the main menu and select a wire type. The available types (e.g., Line, Arc, Circle) are the same as those found under the Draw menu. For example, Fig. 2 shows the Line page of the Draw dialog box when a linear wire type is selected.

The wire must be divided into wire portions based on the desired number of radius steps, as indicated in Fig. 1. Each wire portion with a constant radius should then be subdivided into segments as required by the Method of Moments used in the simulation.

You can define the number of wire portions and the number of segments per portion in the Attributes tab (see Fig. 3). Here, you can also specify the start and end radii of the taper. To set the material properties—including the resistivity of the wire and any coating—use the Materials tab (see Fig. 4). A tapered coating can be specified by assigning start and end thickness values.

In the workspace, wire portions are shown in alternating colors for easier identification.