Marine boiler fuel rate from steam demand, evaporation enthalpy, efficiency and fuel LCV.
Formula
$$ \dot m_\text{fuel} = \frac{\dot m_\text{steam} \cdot h_\text{evap}}{\eta_\text{boiler} \cdot \text{LCV}} $$
Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| $\dot m_\text{fuel}$ | Fuel mass-flow to the boiler | t / h (or kg / h) | result |
| $\dot m_\text{steam}$ | Steam production rate | t / h | boiler design spec |
| $h_\text{evap}$ | Evaporation enthalpy - 2260 MJ/t saturated, higher for superheat | MJ / t | steam tables |
| $\eta_\text{boiler}$ | Thermal efficiency - marine oil-fired 0.85–0.92 | - | boiler-maker data |
| $\text{LCV}$ | Lower calorific value of the boiler fuel | MJ / t (kg × 1000) | MEPC.364(79) / ISO 8217 |
Auxiliary exhaust-gas economisers recover main-engine waste heat and displace boiler fuel at sea - see the Waste-Heat Recovery calculator.
Sources
- Woodyard (Ed.) - Pounder’s Marine Diesel Engines and Gas Turbines.
- IMO MEPC.364(79) - Cf conversion factors.