Direction: In a simple Brayton cycle, the pressure ratio is 8 and temperature at the entrance of compressor and turbine are 300 K and 1400 K, respectively. Both compressor and gas turbine have isentropic efficiencies equal to 80%. For the gas, assume a constant value of cp (specific heat at constant pressure) equal to 1 kJ/kgK and ratio of specific heats as 1.4. Neglect changes in kinetic and potential energies.
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In a 3-stage air compressor, the inlet pressure is p1, discharge pressure is p4 and the intermediate pressures are p2 and p3 (p2 < p3). The total pressure ratio of the compressor is 10 and the pressure ratios of the stages are equal. If p1 = 100 kPa, the value of the pressure p3 (in kPa) is _______.
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- 464.15 kPa
- 454.15 kPa
- 474.15 kPa
- 460.15 kPa
Correct Option: A
| = | = | | = 2.1544 | | P1 | P2 | P3 |
P2 = 2.1544 × 100 = 215.44
| = 2.1544 | P2 |
P3 = 2.1544 × 215.44 = 464.15 kPa
