How to simulate organic rankine cycle — marine diesel exhaust waste-heat recovery
A closed R245fa Rankine loop recovers waste heat from a heavy marine diesel engine's exhaust: a two-stream boiler vaporizes the working fluid against the hot exhaust gas, a real isentropic-efficiency turbine expands it to shaft power, an ambient-cooled condenser returns it to saturated liquid, and a pump restores boiler pressure. The exhaust-gas composition is a representative combustion-product mix (N₂/CO₂/O₂/H₂O), not a specific engine's measured flue analysis.
- 1Open the ready-made model
Open the "Organic Rankine Cycle — marine diesel exhaust waste-heat recovery" 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 r245fa, n2, co2, oxygen, water — already selected, so the phase equilibrium and enthalpy are physically consistent from the first run.
- 3Review the flowsheet
The flowsheet chains PUMP, Boiler, Turbine, Condenser. 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
- r245fa, n2, co2, oxygen, water
- Unit operations
- PUMPBoilerTurbineCondenser
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.
- 1The boiler's cold-outlet temperature is a fixed spec (not an approach-temperature/pinch rating against the real exhaust flow), so this demonstrates cycle convergence and net power, not a bounded heat-recovery-area design.
Frequently asked questions
- What does the Organic Rankine Cycle — marine diesel exhaust waste-heat recovery model simulate?
- A closed R245fa Rankine loop recovers waste heat from a heavy marine diesel engine's exhaust: a two-stream boiler vaporizes the working fluid against the hot exhaust gas, a real isentropic-efficiency turbine expands it to shaft power, an ambient-cooled condenser returns it to saturated liquid, and a pump restores boiler pressure. The exhaust-gas composition is a representative combustion-product mix (N₂/CO₂/O₂/H₂O), not a specific engine's measured flue analysis.
- Which thermodynamic method does it use?
- The PENG-ROBINSON property package, over r245fa, n2, co2, oxygen, water — already selected. You can switch the method on the canvas before running.
- Which unit operations are in the flowsheet?
- It chains PUMP, Boiler, Turbine, Condenser. 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. Organic Rankine Cycle — marine diesel exhaust waste-heat recovery 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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