1) A power cycle for a piston-cylinder device is described by the following four processes 1-2...

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1) A power cycle for a piston-cylinder device is described by the following four processes 1-2 Isothermal compression from 300 K, 100 kPa to 600 kPa 2-3 Constant pressure heat addition until the temperature is 800 K 3-4 Isentropic expansion until the volume at state 4 equals the volume at state 1. Constant volume heat rejection until the temperature is 300 K. 4-1 Sketch the P-v and T-s diagrams for this cycle. 2) Consider an ideal Otto cycle with cold-air-standard assumptions, and compression ratio of 12. The temperature and pressure at the beginning of the compression process are 300 K and 0.1 MPa respectively. The maximum air temperature in the cycle is found to be 1800K. Determine (a) the temperature and pressure at the end of each process of the cycle, (b) the thermal efficiency of the cycle, (c) the mean effective pressure of the cycle, and (d) the entropy change per unit mass for the heat addition and heat rejection processes. 3) Solve problem 2 assuming that the isentropic efficiency of the compression and expansion process is 70%. 1) A power cycle for a piston-cylinder device is described by the following four processes 1-2 Isothermal compression from 300 K, 100 kPa to 600 kPa 2-3 Constant pressure heat addition until the temperature is 800 K 3-4 Isentropic expansion until the volume at state 4 equals the volume at state 1. Constant volume heat rejection until the temperature is 300 K. 4-1 Sketch the P-v and T-s diagrams for this cycle. 2) Consider an ideal Otto cycle with cold-air-standard assumptions, and compression ratio of 12. The temperature and pressure at the beginning of the compression process are 300 K and 0.1 MPa respectively. The maximum air temperature in the cycle is found to be 1800K. Determine (a) the temperature and pressure at the end of each process of the cycle, (b) the thermal efficiency of the cycle, (c) the mean effective pressure of the cycle, and (d) the entropy change per unit mass for the heat addition and heat rejection processes. 3) Solve problem 2 assuming that the isentropic efficiency of the compression and expansion process is 70%.