During the expansion process of the ideal Otto cycle, the gas is a mixture whose volumetric composition is 25 percent nitrogen, 7 percent oxygen, 28 percent water, and 40 percent carbon dioxide. Calculate the thermal efficiency of this cycle when the air at the beginning of the compression is at 12 psia and 55°F, the compression ratio is 7, and the maxi- mum cycle temperature is 1600°F. Model the heat-addition and heat-rejection processes using constant gas properties that are the average of the air and expansion gas properties

During the expansion process of the ideal Otto
cycle, the gas is a mixture whose volumetric composition is
25 percent nitrogen, 7 percent oxygen, 28 percent water, and
40 percent carbon dioxide. Calculate the thermal efficiency of
this cycle when the air at the beginning of the compression is
at 12 psia and 55°F, the compression ratio is 7, and the maxi-
mum cycle temperature is 1600°F. Model the heat-addition
and heat-rejection processes using constant gas properties that
are the average of the air and expansion gas properties.