All unit operations
Fired heater / furnace simulation
2 inlets (process, fuel gas) -> process outlet + flue gas
Governing equations
The exact equations the solver works for a fired heater / furnace — the same math shown in the app's "Theory" panel, not a black box.
- Q_{released}
- total heat of combustion [W]
- F_{fuel,i}
- fuel component i flow [mol/s]
- \mathrm{LHV}_i
- lower heating value of component i [J/mol]
- \eta
- thermal efficiency (design assumption)
- Q_{process}
- duty delivered to the process stream [W]
- Q_{stack}
- unrecovered heat leaving as flue-gas sensible heat [W]
- F_{flue}
- flue-gas molar flow [mol/s]
- T_{stack}
- flue-gas stack temperature [K]
- T_{amb}
- ambient temperature [K]
- H
- stack height [m]
Parameters
inlets: [process feed, fuel gas]; exactly one of duty [W] OR outlet_temperature [K]; optional efficiency [0-1, default 0.85], excess_air_fraction [default 0.15], ambient_temperature [K, default 298.15], stack_height [m, default 30], pressure_drop [Pa]. Fuel gas composition drives combustion stoichiometry (methane, ethane, propane, n_butane, h2, co recognized; other components pass through as inerts). Reports q_released, stack_loss, flue_gas_flow, stack_temperature, draft [Pa, natural chimney draft]