magnetostatics

Solves for the 2D magnetic vector potential on a grid by relaxation, then draws the flux density as a heatmap with field lines traced as exact contours of the potential — not an approximation, that's just what constant-A contours are in a planar field. Pick a preset, pick materials, hit solve.

Problem

preset

—

flux heatmap field lines

Material library

|B| flux density (heatmap) + field lines (contours of A)

0max

Model: linear materials (no saturation), 2D (translation-invariant in z), Dirichlet A=0 at the domain edge as a far-field stand-in. Permanent magnets are modeled as the equivalent bound surface currents of a uniformly magnetized block (the Amperian-loop picture) — the same current sheets a solenoid uses in the limit. Solved by SOR relaxation in a small Rust crate compiled to wasm32-unknown-unknown with no wasm-bindgen — plain exported pointers into wasm linear memory, read/written as Float32Array views. Source: rust/magnetostatics.