Release History

The first commercial release. Nabla is now a licensed product with a free tier: Nabla Free runs out of the box with no key, capped at 25,000 mesh nodes, and the Core and Machines editions unlock the rest. See pricing and the feature matrix.

New features

• Machines module — parametrised PMSM, induction and fractional-slot designs, inner- and outer-rotor topologies, with windings, external circuits, squirrel cages and rotor/stator skew.
• Thermal module — steady-state and transient heat conduction, planar and axisymmetric, on the same mesh.
• Time-harmonic solver for eddy-current and frequency-domain problems, with nonlinear effective permeability.
• Crank-Nicolson time integration alongside backward Euler.
• Second-order (quadratic) elements across the planar, axisymmetric, time-harmonic and thermal solvers.
• Far-field (balloon) boundary condition, so an open model's outer boundary can sit at 2-3x the device radius instead of 20x.
• Multiple motion zones in one model, rotary or linear — counter-rotating rotors, magnetic gears, linear movers.
• Performance analysis for induction machines and PMSMs: equivalent-circuit extraction, torque/speed and efficiency curves, efficiency and loss maps, loss breakdowns.
• Nine worked examples shipped in the application under Help → Examples, each with a build script and notes.
• Python API and MCP server for scripted studies and agent-driven automation.
• Windows installer with a per-user install, a bundled user manual and an optional Triangle download step.

Performance

• Monolithic field-circuit solve replaces the staggered iteration, removing its convergence stalls on strongly coupled models.
• The large-mesh ceiling is gone — meshes far beyond the previous ~130,000-node limit now solve.
• Faster induction-machine equivalent-circuit extraction via a time-harmonic route.

Corrections that change results

• Airgap torque now uses the Arkkio volume integral over the whole gap layer. The previous single-contour form read the mesh as much as the field, and was radius-dependent.
• Iron-loss post-processing corrected; earlier builds over-reported it substantially.
• Field energy, force and field probes read the element's own material rather than a nodal average, which had smeared values across material interfaces.
• Meshing now refuses a model whose sliding band or region seeds are mis-drawn, instead of solving it silently wrong.
• Coil resistance, phase flux linkage and dq-frame voltages corrected.

Model format

• Models are saved as .nbl (format version 2), which records material identity rather than a bare index, so a model opens with the materials it was built with on any machine.
• Older .json and .ujsn models are migrated by opening and re-saving them. Files written before 1.0 carry no format stamp and need File → Open (legacy, unverified).

Download Nabla 0.1.0