Use constant specific heats at room temperature. Round final answers to one decimal place
A spark-ignition engine has a compression ratio of 7.9, an isentropic compression efficiency of 83.3%, and an isentropic expansion efficiency of 95.9%. At the beginning of the compression the air in the cylinder is at 13 psia and 60 °F. The maximum gas temperature is found to be 2300 °F by measurement.
Determine the
a) specifc heat addition, (Btu/lbm)
b) thermal efficiency, (%)
c) mean effective pressure of this engine when modeled with the Otto cycle. (psia)