Licensing and activation
The free tier
Section titled “The free tier”The free build is the same binary as the paid one. There is no separate download and no trial timer.
The authoritative list is docs/licensing/tiers.json in this repository — the
application compiles it in, because the free tier has to work with no account
and no network and so has nobody to ask.
| Free | |
|---|---|
| Mesh size | 250,000 cells |
| Cores | 1 |
| Analysis types | Incompressible, Compressible, Convective Heat Transfer, Solid conduction, Scalar transport |
| Cell zones | Not available — no MRF, AMI, overset, porous media or sources |
| Multi-region | Not available, so conjugate heat transfer needs a licence |
| Remote execution | No |
| Reports | Watermarked |
The five analysis types cover most first jobs: external and internal flow, compressible flow, buoyancy-driven convection, conduction through a solid, and tracking a passive scalar. Free-surface, multiphase, reacting, particle and rotating-machinery work needs a licence.
An engineer who discovers a cap after installing is annoyed; one who read it and installed anyway is qualified. That is why the list is here and on the download page rather than in a footnote.
Activating a paid licence
Section titled “Activating a paid licence”Two routes. Both end in the same place.
Sign in. The application opens a browser, you sign in to your account, and the machine is activated against a seat. Use this one — it is fewer steps and it attaches the machine to a person, which is what makes seat management work later.
Enter a licence key. Paste the key from your account. This works with no browser and on a machine that cannot reach a sign-in page.
The difference matters when somebody leaves. A machine activated by signing in can be stopped by removing that person from the organisation; a machine activated by typing a key carries no identity, so it has to be deactivated from the Devices screen. The application says so at the point you choose.
Working offline
Section titled “Working offline”Once activated, the application does not need the network to run. It holds a signed licence file and revalidates periodically; if it cannot reach the licence server it keeps working for a 14-day grace period.
The grace period is deliberately generous and deliberately finite. It covers a site visit, a flight, a customer network that blocks everything — not permanent offline use. If you need genuinely air-gapped activation, that is an Enterprise arrangement rather than a setting.
When a licence lapses, the application degrades to the free tier. It does not lock your cases, make them read-only, or delete anything. Your work stays openable.
Seats and devices
Section titled “Seats and devices”A licence is per seat. What a seat means depends on the licence:
- Named — assigned to a person. They can activate their machines; nobody else can use that seat.
- Floating — a pool. Any member of the organisation can take a seat until the pool is empty.
Manage both at account.shd-sim.com, under Licences and Devices. Deactivating a device frees its seat immediately.
Moving to a new machine
Section titled “Moving to a new machine”Deactivate the old one first, from its licence panel or from the Devices screen in your account. Then activate the new one normally.
If the old machine is gone — dead, wiped, stolen — deactivate it from the Devices screen. You do not need the machine to release its seat.