stem_material

This crate provides a Material definition for simulation of electromagnetic devices – especially electric motors – built on top of the var_quantity crate. It is used to define motor components within stem - a Simulation Toolbox for Electric Motors. See the stem book for an introduction to the framework.

Due to the aforementioned tight coupling with var_quantity, this crate reexports it. It also heavily relies on the uom crate for providing static quantities. The resulting interface is therefore hard to misuse, as it doesn't matter whether e.g. the density of a material is given as kg/m³ or as g/cm³ - uom will take care of the conversions automatically.

Modeling soft magnetism

Even though this crate is foundational for stem, some of its components might also be useful outside of it. In particular, it offers the following types to model soft magnetism:

• The FerromagneticPermeability struct offers a spline-based way to model the ferromagnetic behaviour of a material from measured datapoints. It is particularily optimized for usage with iterative solvers and slightly modifies the resulting curve to achieve numerical stability and fast convergence. It models both µr = f(H) and µr = f(B), meaning that either the magnetic field strength H or the magnetic flux density B can be used to calculate the relative permeability of a material.
• The JordanModel type provides a simple and fast model for calculating hysteresis and eddy current losses based on the equation p = kh * f * B² + kec * (f * B)². The accompanying module offers ergonomic ways to obtain the the loss coefficients kh and kec using least-square fitting.

Serialization and deserialization

The serde integration is gated behind the serde feature flag.

Most of the types (except errors) in this crate implement serialization and deserialization. See the docstrings of the individual types for details.

Documentation

The full API documentation is available at https://docs.rs/stem_material/0.1.1/stem_material/.