Question

**1)** An ideal gas is contained in a
piston-cylinder device and undergoes a power cycle as follows:

1-2 isentropic compression from an initial
temperature*T*1= 20 degree celsius with a compression ratio
*r =* 5

2-3 constant pressure heat addition 3-1 constant volume heat rejection

The gas has constant specific heats with *c*v = 0.7
kJ/kg·K and *R=* 0.3 kJ/kg·K.

**(***a***)** Sketch the
*P-*v *and T-s* diagrams for the cycle.

**(***b***)** Determine the heat
and work interactions for each pro-cess, in kJ/kg.
**(***c***)**
Determine the cycle thermal efficiency.

Answer #1

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