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In: Mechanical Engineering

An ideal diesel engine uses air as the working fluid and operates with a thermal efficiency...


An ideal diesel engine uses air as the working fluid and operates with a thermal efficiency ?th =0.5 with a rate of heat addition Qin=120 kW. The temperature at the beginning and the end of the addition heat (combustion) are respectively: T2=900 K and T3=2100 K. Assume constant specific heats (Cp and Cv). The air properties at a room temperature T1=293.0 K are: Cp=1.005 kJ/kg.K, Cv=0.718KJ/kg.K, the gas constant of air is R=0.287 kJ/kg.K and the ratio of specific heats k=1.4. Calculate:
a/ The network Wnet and the rate of the heat rejected Qout in kW.
b/ The mass flow rate of the air mair.
c/ The cutoff ratio rc.and the compression ratio r.
d/ T4

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samet mamat answered 2 years ago
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