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.