https://www.youtube.com/watch?v=2IKECt4Y3RI

The Rankine Cycle Improvements

Rankine Cycle Rankine Cycle with Superheat Notes 1. The larger average temperature at which heat is added in a Superheat Rankine cycle results in a larger

efficiency as compared to an ordinary Rankine cycle.

s

T

1

2s 3

4s

a

p4s = pa = p1 = constant

p2s = p3 = constant < p4

s

1

2s 3

4s

a

p4s = p4 = pa = p1 = constant

p2s = p2 = p3 = constant < p4

2

4

T

Rankine Cycle with Reheat

Notes 1. The larger average temperature at which heat is added in a Reheat Rankine cycle results in a larger

efficiency as compared to an ordinary Rankine cycle. 2. The 1st stage turbine typically exits in the SHV phase (State 2). In addition, the quality at the exit of

the 2nd stage turbine (State 4) is larger than that in an ordinary Rankine cycle.

s

T

1

2s

5

6s

a

p6s = pa = p1 = constant

p4s = p5 = constant < p3 < p1

3

4s

p2s = p3 = constant < p1

Rankine Cycle with Supercritical Reheat Notes 1. The larger average temperature at which heat is added in a Supercritical Rankine cycle results in a

larger efficiency as compared to an ordinary Rankine cycle. 2. The 1st stage turbine typically exits in the SHV phase (State 2). In addition, the quality at the exit of

the 2nd stage turbine (State 4) is larger than that in an ordinary Rankine cycle. 3. The large pressures and temperatures in a Supercritical Rankine cycle requires the use of high pressure

piping and steam generator, and turbine materials that can withstand high temperatures. 4. Efficiencies up to 47% can be achieved in a Supercritical Rankine cycle power plant.

s

T

1

2s

5

6s

p2s = p3 = constant

p4s = p5 = constant < p3

3

4s