Methanol synthesis reactor duty (Python Script Mode, LHHW kinetics) — a PENG-ROBINSON process flowsheet
A CO/H₂ syngas feed enters a custom block written in real, sandboxed Python (flowsim/sandbox/) rather than the AST-restricted equation grammar — the case equation mode structurally can't express: a Langmuir-Hinshelwood-Hougen-Watson rate law (a forward kinetic term over a competitive-adsorption denominator, each term Arrhenius/ van't-Hoff temperature-dependent) evaluated inside a real Python loop over the adsorbing species, driving the exothermic reactor's temperature rise. Partial pressures are computed from the real inlet pressure (pinned via inputs) and representative mole fractions (script_params — composition itself can't be pinned into a script, only flow/T/P, so the fractions are illustrative constants, not read from the flowsheet's actual feed). The kinetic/adsorption/heat-of-reaction constants are likewise illustrative (chosen for a physically plausible rate and duty, not fit to a specific published dataset) — the point is the execution model, not a validated methanol-synthesis kinetic scheme.
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- Rigorous PENG-ROBINSON thermodynamics, solved by the same engine every simulation runs on.
- 1 unit operations modeled: RX.
- Focus areas: Python Script Mode, LHHW kinetics, Sandboxed Python, Custom block.
- Thermodynamics
- PENG-ROBINSON
- Components
- carbon_monoxide, h2
- Unit operations
- RX
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("lhhw-methanol-synthesis-kinetics")
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
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