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In: Mechanical Engineering

The compression ratio is 8 in an engine working with the ideal Otto cycle. The heat...

The compression ratio is 8 in an engine working with the ideal Otto cycle. The heat transfer to the engine takes place from a heat source at a temperature of 1000 ° C and the heat transfer from the engine to the outside takes place in the environment of 20 ° C and 100 kPa. At the start of the isentropic compression process, the temperature is 50 ⁰C and the pressure is 110 kPa. The temperature at the end of the combustion process is 900 ⁰C. Calculate the pressures and temperatures at all points of the cycle, the thermal efficiency of the cycle and the thermal efficiency of the Carnot cycle operating between the same high and low temperature sources (k = 1.4 cv = 0.718 kj / kg.K) by accepting specific temperatures as constant.

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