sCO2 Allam-Fetvedt oxy-combustion power cycle — a PENG-ROBINSON process flowsheet
Natural gas burns in near-pure oxygen, diluted by a large recycled supercritical-CO₂ flow instead of air's nitrogen — the oxy-combustion, near-critical-CO₂ cycle that yields pipeline-ready CO₂ with no separate capture step. Main compressor takes CO₂ from just above its critical point (310 K, 8 MPa vs. Tc=304 K/Pc=7.38 MPa) to 30 MPa; the combined CO2+combustion-product stream expands through a real isentropic-efficiency turbine, still supercritical throughout.
Modeling assumptions & limitations
- 1This is an open-cycle v1, not the fully closed recuperated loop — the compressor's CO₂ feed and the turbine's exhaust aren't tied together via a recuperator/recompression recycle yet (a stated follow-up), so read this as 'does the near-critical compression + oxy-combustion + supercritical expansion chain converge and deliver net power', not a bounded plant design.
- 2The combustor's ambient_temperature param is reused as the recycled-CO₂ inlet temperature (a naming artifact of the air-furnace origins), not true ambient.
- 3Turbine-inlet temperature here (~760 K) is lower than a commercial Allam design's ~1150 degC — that gap is exactly what the missing recuperator would close by preheating the recycle CO₂ before combustion.
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- Rigorous PENG-ROBINSON thermodynamics, solved by the same engine every simulation runs on.
- 4 unit operations modeled: Compressor, Combustor, Turbine, TRIM Cooler.
- Focus areas: sCO2, Allam cycle, Oxy-combustion, Carbon capture, Power generation.
- Thermodynamics
- PENG-ROBINSON
- Components
- co2, methane, oxygen, water, argon
- Unit operations
- CompressorCombustorTurbineTRIM Cooler
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("allam-fetvedt-cycle")
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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