Consider the air-standard Otto cycle described in Problem 9.94 operating with a compression ratio of 10 (= V_max/V_min). The air just prior to compression is at 70 F and 14.7 psia. The maximum cycle temperature is 4500 F. Assuming constant specific heats, determine the temperature and pressure at the beginning of each process and the thermal efficiency for the cycle.

Problem 9.94

1-2 : Internally reversible, adiabatic compression from the maximum volume V_max to the minimum volume V_min.

2-3 : Constant-volume heat addition to a peak cycle temperature T₃.

3-2 : Internally reversible, adiabatic expansion from V_min to V_max.

4-2 : Constant-volume heat rejection to return to the initial state.

Sketch this cycle using P–V and T–S coordinates, labeling each state point (1, 2, 3, and 4).

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