A process simulator that runs in your browser: steady-state, pressure-driven and dynamic flowsheets, rigorous thermodynamics, and an AI copilot that builds and explains them. There is nothing to install.

Does the AI calculate the results?

No. The copilot proposes a flowsheet or a change and explains it; the deterministic solver computes every temperature, duty and composition you see. A flowsheet from the copilot that does not validate is not applied.

Will it feel familiar if I have used Aspen Plus or HYSYS?

That is the intent. The workbench has a ribbon, an All Items tree, a form for each block and the three run modes — steady state, pressure driven and dynamics — so the habits carry over.

Can it open my Aspen or HYSYS cases?

Aspen Plus .bkp and .apw, HYSYS .hsc and DWSIM files import with deterministic parsing and a report of what was recovered. A HYSYS .hsc import is partial — unit names and types, not connectivity — and the report says so.

Which thermodynamic models are included?

Peng-Robinson and SRK (including Gᴱ mixing rules), NRTL, UNIQUAC, UNIFAC, PC-SAFT, CPA, GERG-2008, electrolyte NRTL, Pitzer and the IAPWS steam tables — more than 30 property packages in all.

Yes. The Python SDK (pip install flowsim-sdk) creates, runs and reads simulations, and its results are the same objects the canvas shows.

How much does it cost?

It is free to start, with no credit card. Paid plans add higher limits and team features; the pricing page has the details.

Dense-medium separator simulation

ore (+ medium) -> sinks + floats (Tromp partition on particle density)

Simulate it free Browse example flowsheets

Governing equations

The exact equations the solver works for a dense-medium separator — the same math shown in the app's "Theory" panel, not a black box.

P(\rho) = \frac{1}{1 + \exp\big(\ln 3\,(\rho_{50} - \rho)/E_p\big)}

E_p = \tfrac{1}{2}(\rho_{75} - \rho_{25}),\quad E_p(d) = E_p\,(d_{ref}/d)^{n}

\rho_{particle} = \Big(\sum_m w_m/\rho_m\Big)^{-1}

$P(\rho)$: fraction of particles of density ρ reporting to the sinks
$\rho_{50}$: cut density — half the particles report to the sinks [kg/m^3]
$E_p$: écart probable [kg/m^3]
$\rho_{25}, \rho_{75}$: densities with 25% and 75% to the sinks [kg/m^3]
$d_{ref}, n$: reference size [m] and exponent of the Ep size scaling
$w_m, \rho_m$: mass share and density of mineral m in a particle
$\rho_{particle}$: particle density [kg/m^3]

Parameters

cut_density_kg_m3 [kg/m^3, required — the Tromp ρ50], ecart_probable_kg_m3 [kg/m^3, required — Ep = (ρ75 − ρ25)/2; 0 = perfect]; optional ep_reference_size_m [m] + ep_size_exponent [-] (Ep(d) = Ep·(d_ref/d)^n), mineral_densities_kg_m3 [{mineral: kg/m^3} — else the feed's mineral_texture, else the cited table], valuable_mineral + grain_size_m [m] (liberation: composites sort on their own density), liquid_to_sinks [0..1, required with a liquid inlet], assay [{name: {mineral: mass fraction}} — e.g. p2o5 publishes P2O5 and BPL grades]. Needs solids.psd + psd_minerals

Dense-medium separator simulation

Governing equations

Parameters

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