Consider one cylinder of a spark-ignition, internal-combustion engine. Before the compression stroke, the cylinder is filled with a mixture of air and methane. Assume that 110% theoretical air has been used, that the state before compression is 100 kPa, 25C. The compression ratio of the engine is 9 to 1.
a. Determine the pressure and temperature after compression, assuming a reversible adiabatic process.
b. Assume that complete combustion takes place while the piston is at top dead center (at minimum volume) in an adiabatic process. Determine the temperature and pressure after combustion, and the increase in entropy during the combustion process.
c. What is the irreversibility for this process?