Continuous polymerization -> inline devolatilization -> melt transfer — a FLORY-HUGGINS process flowsheet
A continuous free-radical CSTR (Mn/Mw/PDI via method-of-moments) converts 10% of its monomer feed to polymer per pass; the effluent flashes above its real Flory-Huggins bubble point to strip most of the residual monomer for recycle (the same physics as the polystyrene-devolatilization example, chained directly onto a reactor for the first time). The still-solvent-carrying melt then transfers through a pipe whose pressure drop is driven by a real non-Newtonian melt viscosity — the 3.4-power Mw scaling law plus Carreau shear-thinning, not a flat user-guessed constant — closing the 'viscosity-driven hydraulic pressure drop' gap a competitive pitch this session flagged as unbuilt.
Modeling assumptions & limitations
- 1'ethanol'/'polymer' are the Flory-Huggins-package's actual solvent/polymer ids (the same stand-in-carrier convention the free-radical-polymerization example already uses, with monomer_mw overridden to styrene's real 104 g/mol) — a real bulk process pushes further toward a solids-rich melt, but the Flory-Huggins flash's own bubble-point search becomes numerically unreliable very close to the solvent's critical point at high polymer loading (found while building this example), so the reactor conversion here is tuned to a regime that flashes cleanly and monotonically rather than chasing an unverified near-critical number.
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- Rigorous FLORY-HUGGINS thermodynamics, solved by the same engine every simulation runs on.
- 3 unit operations modeled: POLY, Devol, MELT PIPE.
- Focus areas: Polymer, Devolatilization, Melt viscosity, Non-Newtonian, Pipeline.
- Verified fast convergence — a real, measured solve time, not an estimate.
- Thermodynamics
- FLORY-HUGGINS
- Components
- ethanol, polymer
- Unit operations
- POLYDevolMELT PIPE
Opens in a new tab, loaded straight into the app — no setup.
Read the step-by-step guideReproduce this exact result from Python — the real client.get_example() → run_and_wait() path, not a mockup.
from flowsim.sdk import FlowSimClient
client = FlowSimClient()
example = client.get_example("polymerization-devolatilization-melt-transfer")
sim = client.create_simulation(example["title"], example["flowsheet"])
result = client.run_and_wait(sim["id"])
print(result["status"]) # "converged"
streams = client.streams(sim["id"])Related models
Polystyrene devolatilization (Flory-Huggins)
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The same monomer feed, split 50/50 into two trains at equal total reactor volume: a 3-stage CSTR cascade (each stage blending its own new polymer with the MWD already carried by the stream from the stage before it) versus a single tubular (PFR) reactor. Both converge to a real, different Mn/Mw/PDI — the PFR reaches higher conversion at the same total volume, but its cumulative polydispersity is measurably broader than the cascade's, because chain length drifts continuously with conversion along the tube while each CSTR stage makes its own local production under one fixed monomer concentration. See the 'Polymerization Reactors' docs page for the full reasoning.
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