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In: Mechanical Engineering

Consider an automobile engine which operates on the ideal Otto cycle. In this engine, air is...

Consider an automobile engine which operates on the ideal Otto cycle. In this engine, air is compressed with a compression ratio of 10. At the beginning of the compression process, air is at 105 kPa and 17oC, and in the combustion process 640 kJ/kg of heat is added to air. Taking into account the variation of specific heats with temperature, determine (a) the pressure and temperature at the end of the heat-addition (combustion) process, (b) the net work output, (c) the thermal efficiency of the engine, and show the cycle on a P-ν diagram.

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