How to simulate sco2 allam-fetvedt oxy-combustion power cycle
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.
- 1Open the ready-made model
Open the "sCO2 Allam-Fetvedt oxy-combustion power cycle" model in the MaximaLabs workspace — no install, no license. It loads live on the canvas, ready to edit and run.
- 2Confirm the thermodynamics
This process is modeled with the PENG-ROBINSON property package over co2, methane, oxygen, water, argon — already selected, so the phase equilibrium and enthalpy are physically consistent from the first run.
- 3Review the flowsheet
The flowsheet chains Compressor, Combustor, Turbine, TRIM Cooler. Every block is a real, solvable unit op you can reconfigure on the canvas.
- 4Run the simulation
Click Run. The deterministic solver converges the material and energy balances (recycles included) and fills the live stream table — the AI never invents a number.
- 5Read the results and iterate
Inspect the converged streams, tweak a spec, and re-run — or ask the AI copilot to explain a result or diagnose a failed solve in plain English.
- Thermodynamics
- PENG-ROBINSON
- Components
- co2, methane, oxygen, water, argon
- Unit operations
- CompressorCombustorTurbineTRIM Cooler
Opens live on the canvas — free, no install.
Explore the model & flowsheetModeling assumptions & limitations
What this model captures, and what it deliberately does not — from the engineers who built it.
- 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.
Frequently asked questions
- What does the sCO2 Allam-Fetvedt oxy-combustion power cycle model simulate?
- 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.
- Which thermodynamic method does it use?
- The PENG-ROBINSON property package, over co2, methane, oxygen, water, argon — already selected. You can switch the method on the canvas before running.
- Which unit operations are in the flowsheet?
- It chains Compressor, Combustor, Turbine, TRIM Cooler. Every block is a real, solvable unit operation you can reconfigure, add to, or remove.
- Do I need to install software or buy a license?
- No. sCO2 Allam-Fetvedt oxy-combustion power cycle runs entirely in your browser on MaximaLabs — free, no install, no license. Open the model to load it live and run the deterministic solver.
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