HomeCalculatorsBrake Thermal Efficiency

Brake Thermal Efficiency

Brake thermal efficiency from SFOC and fuel LCV. η_th = 3600 / (SFOC · LCV).

Engine
Brake thermal efficiency
50.79%
Formula, assumptions, and limits

Modern long-stroke two-stroke with Miller timing can reach 52–54 % on HFO (SFOC ≈ 167, LCV ≈ 40.5). Four-stroke medium-speed 45–48 %. Spark-ignited gas engines 42–46 %.

Symbol legend

SymbolMeaningUnitSource
Specific fuel oil consumptiong/kWhNOx technical file
Lower calorific valueMJ/kgISO 8217 / MEPC.364
Brake thermal efficiency - result