Organic Rankine Cycle — marine diesel exhaust waste-heat recovery — a PENG-ROBINSON process flowsheet
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.
Modeling assumptions & limitations
- 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.
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- Rigorous PENG-ROBINSON thermodynamics, solved by the same engine every simulation runs on.
- 4 unit operations modeled: PUMP, Boiler, Turbine, Condenser.
- Focus areas: ORC, Waste heat recovery, Marine, Closed loop, Rankine cycle.
- Thermodynamics
- PENG-ROBINSON
- Components
- r245fa, n2, co2, oxygen, water
- Unit operations
- PUMPBoilerTurbineCondenser
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("orc-marine-waste-heat")
sim = client.create_simulation(example["title"], example["flowsheet"])
result = client.run_and_wait(sim["id"])
print(result["status"]) # "converged"
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