Ferrion

Free to download: every workspace at full fidelity on the bundled examples, exports unrestricted, no account. One optional unlock brings your own STL. No subscription.

Engineering simulation that runs on your own Mac or iPad.

Ferrion answers the questions you would otherwise guess at. Pick a workspace, start with an example, run it, then read the numbers. The solvers run on the device in front of you, several of them on its GPU. No account, no upload, no cloud queue, and nothing to wait on but the machine you already own.

TWELVE WORKSPACES

Each one asks a different question, and shows only the controls that question needs.

• Studio - the full toolset: every solver, view and control • Hobby - wings and bodies: lift and drag at a glance • Pipe - internal flow in a round pipe: developed velocity profiles • Network - enclosures and manifolds: ports, flow split, balance • Structure - bending and torsion: fix it, load it, and see how the solid deforms • Buoyancy - import a hull, set its mass and centre of gravity: find how it floats, and when it capsizes • Rotor Wake - set rotor axes and RPM: see where the tip vortices go and how they interact • Rotor Loading - spin a rotor and watch the blades bend: how much of your design pitch survives the load

Four more are marked Experimental in the app. Useful today, still being validated, and these results may change between releases:

• Plasma - ionic wind and EHD: electrodes, charge and electric fields • Heat Exchanger - two fluid circuits trading heat through solid walls • Cavitation - find the RPM where a propeller starts to cavitate, and where on the blade • Propeller - thrust, torque and power against RPM, in air or water

IS IT RIGHT?

The question worth asking of any simulation. Here is what we can defend:

• Sphere drag lands within 0-3% of the Schiller-Naumann correlation, which itself sits within about 2% of experiment across that range. • Structure's cut-cell stress is gated against the analytic Kirsch factor, Kt = 3.3. • Rotor wake geometry is gated against Landgrebe and Caradonna-Tung to 0.013 rotor radii. • Buoyancy clips the hull against the waterplane exactly, with no grid and no cells. Given a watertight mesh there is no discretisation error in the answer at all. • Propeller shaft power lands within about 3% of published data. Thrust currently reads 20-25% low, which is a leading-edge resolution limit rather than a physics one. Use it for trends and for comparing two props, not as an absolute design number. It is marked Experimental for exactly that reason.

We would rather tell you than have you find out.

FREE, AND FREE IS NOT A DEMO

Every workspace runs at full fidelity on its bundled examples. Nothing is resolution-capped, time-limited or watermarked, so a free user's numbers are the same numbers. Every export is unrestricted: CSV data, Markdown reports, photos and video.

USE YOUR OWN GEOMETRY

One optional in-app purchase adds the one thing held back - your own geometry:

• Import your own STL, binary or ASCII, into any workspace • Synthesize parametric rotors from a section, blade count, radii, taper and twist

One purchase, no subscription, and it works in every workspace. Family Sharing supported. If you bought Ferrion before it became free, it is already yours.

REQUIREMENTS

macOS 14 or later, or an iPad running iPadOS 17 or later. There is no iPhone version.