Thermodynamic Cycle Analysis of an Automotive Internal Combustion Engine With the Characteristics of the Commercial BMW N54 Spark-Ignition Model

An analytical method is presented for the thermodynamic analysis of an automotive internal combustion engine with the characteristics of the commercial BMW N54 spark-ignition model. A 3-L displacement volume, six in-line cylinder, four-stroke gasoline engine is considered with two 0.57 bar boost pressure turbochargers and an air-to-air intercooler. Thermodynamic, fluid flow, and heat transfer phenomena are mathematically analyzed to provide results on the chemical composition of the cylinder gases, on their temperature and pressure, on the amount and properties of the residual exhaust gases, on the volumetric and mechanical efficiencies, on the specific fuel consumption, the torque and brake power output, the thermal efficiency, and the energy balance of the engine. The analysis provides results in very close agreement with the actual torque and brake power characteristics reported by the BMW manufacturer.