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In: Mechanical Engineering

An ideal Otto cycle uses air as the working fluid; its state at the beginning of...

An ideal Otto cycle uses air as the working fluid; its state at the beginning of the compression is 120 psia and 60°F, its temperature at the end of the combustion is 1500°F, and its compression ratio is 9. Use constant specific heats at room temperature. Determine the rate of heat addition and rejection for this ideal Otto cycle when it produces 120 hp. The properties of air at room temperature are R = 0.3704 psia·ft3/lbm·R, cp = 0.240 Btu/lbm·R, cv = 0.171 Btu/lbm·R, and k = 1.4.

The rate of heat addition is ____________ Btu/h.

The rate of heat rejection is ___________________ Btu/h.

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