What's in Free, Core and Machines

Nabla Free is a permanent, full-featured tier - not a time-limited trial. Core and Machines are cumulative: Machines includes everything in Core. See pricing for cost and how to buy.

✓ = included. Machines includes everything in Core; Core includes everything in Free. Full legal detail in clause 3 of the Licence Agreement.
Capability Free Core Machines
2D magnetostatic, transient, planar & axisymmetric
First-order (P1) elements
One motion zone (rotary or linear)
Circuit editor (R, L, C, sources, switches)
Materials library
Material editor and curve fitting
DXF import and export
Mesh node cap25,000UnlimitedUnlimited
Report watermarkYesNoNo
Core Pro - included in both paid editions
Time-harmonic solves
2nd-order (P2) elements
Far-field (balloon) boundary condition
Multiple simultaneous motion zones
Crank-Nicolson time integration
Thermal - included in both paid editions
Steady and transient heat conduction
Convection, fixed-temperature, heat-flux BCs
Time-dependent volumetric heat sources
Automation - included in both paid editions
Python API and headless batch runs
MCP server (LLM-driven modelling)
Machines - Nabla Machines only
Parametric PMSM and IM builders
Windings setup, skew, stator/rotor customisation
Machine PDF report
Performance - Nabla Machines only
Efficiency and loss maps, performance curves
MTPA / MTPV trajectories, torque vs speed
IM equivalent circuit extraction
Demagnetisation risk analysis

The Performance entitlement requires Machines to be present as well - granting a higher tier implicitly grants every tier below it, so the upgrade from Core to Machines is one step.

Solver Capabilities

Magnetostatic & Transient Magnetics Free

2D vector-potential formulation, planar and axisymmetric, with permanent magnets, current-carrying conductors and nonlinear magnetic materials.

  • Inductance, force and torque computation
  • Flux density mapping
  • First-order (P1) elements

Time-Harmonic Analysis Core

Frequency-domain (K + jωM) solves with an effective-permeability nonlinear iteration, for AC problems where a full transient run isn't needed.

Second-Order (P2) Elements Core

Quadratic 6-node triangles for planar, axisymmetric and time-harmonic problems, plus the thermal module - higher accuracy per node than P1.

Motion Without Remeshing Free Core

Rotary or linear motion through a sliding band, not a moving mesh. One motion zone is free; Core adds multiple simultaneous zones (two rotors, mover/mover interfaces) and Crank-Nicolson time integration.

  • Rotating and linear machinery simulation
  • Rotor/stator skew (multi-slice, Machines)

Eddy-Current Analysis Free

Induced currents in conductive media under time-varying magnetic fields.

  • Skin and proximity effects
  • Eddy-current losses

Circuit Coupling Free

An embedded Modified Nodal Analysis (MNA) circuit solver, coupled directly to the field solve.

  • Resistors, inductors, capacitors
  • Voltage/current sources and switches
  • Coils wired directly into the circuit

Far-Field (Balloon) Boundary Core

An asymptotic open-boundary termination that lets an unbounded model's outer edge sit at 2-3x the device radius instead of 20x.

Nonlinear Material Support Free

B-H curve materials with saturation, solved by a consistent Newton iteration.

  • Iron loss (Steinmetz) in laminated steels
  • Anisotropic permeability

Thermal Module Core

Steady-state and transient heat conduction on the same mesh as the electromagnetic model, planar or axisymmetric.

  • Convection, fixed-temperature and heat-flux boundary conditions
  • Time-dependent volumetric heat sources
  • Electromagnetic loss results fed in directly as a heat source

Automation Core

Every capability above is scriptable, headless, from outside the GUI.

  • Python API - geometry, meshing, solve, post-processing
  • MCP server (~130 tools) for LLM-driven modelling
  • Batch/CI runs with no display attached

Machine Design Tools Machines

Parametric Machine Builders

PMSM (radial, outrunner, Halbach) and induction machine topologies built from parameters, not drawn by hand - slot/pole advisor included.

Windings & Rotor Tools

Winding layout tools, rotor/stator skew, custom-rotor DXF import, and the squirrel-cage builder for induction rotors.

Machine Analysis

Back-EMF, cogging torque, Ld/Lq extraction, the induction-machine equivalent circuit, and mass estimation.

PDF Report

A shareable machine performance report generated directly from the model.

Performance Analysis Machines

Maps & Curves

Efficiency and loss maps over the full drive envelope, torque-vs-speed and MTPA/MTPV trajectories.

Induction Machine Extraction

Equivalent-circuit parameter extraction from a handful of FEM solves.

Demagnetization Risk

Per-magnet risk analysis against the knee of the demagnetization curve.

Boundary Conditions

Dirichlet & Neumann Free

Fixed potential and specified-flux edges - the two building blocks every model uses.

Periodic & Anti-Periodic Free

Model a repeating sector instead of the full machine, circular or parallel.

Sliding Band Free

What makes motion possible without remeshing - couples a moving ring to a stationary one across an air gap.

Far-Field (Balloon) Core

An open-boundary termination for unbounded problems - see above.

Thermal Boundary Conditions Core

Fixed temperature, heat flux and convection, for the thermal module.

Numerical Methods

FEM Solvers

  • Direct: Simplicial LDLT decomposition
  • Iterative: Conjugate Gradient (CG)
  • Consistent Newton iteration for nonlinear materials

Electric Circuit Solver

  • Modified Nodal Analysis (MNA)
  • Trapezoidal (Crank-Nicolson) companions Core

Geometry & Meshing

CAD Import & Export

Import or export geometry as DXF, or draw directly with the built-in line/arc/circle tools.

Material Editor Free

Define and curve-fit your own B-H and loss data - free on every tier, same as the base material library.

Mesh Generation

An open-source Two-Dimensional Quality Mesh Generator and Delaunay Triangulator

Up to 25,000 nodes on Free; unlimited on Core and Machines.

Parametric Geometry Machines

The parametric PMSM/induction machine builders above generate geometry from parameters directly - see Machine Design Tools.

Post-Processing & Visualization

Field Plots & Probes

Contour, vector and streamline plots; point, contour and shape probes for B, H and derived quantities.

Forces, Torque & Losses

Maxwell-stress (eggshell/Arkkio) force and torque, Joule and iron losses.

Data Analysis & Export

Analyze results with built-in tools, or export to CSV or via the Python API.

Fast Animation Engine

GPU-accelerated OpenGL animation of time-domain and time-harmonic results.