Microsoft Word - Cengel and Boles TOC _2-03-05_.doc

or, (10–3) where (10–4) Boiler(w
0): (10–5) Turbine(q
0): (10–6) Condenser(w
0): (10–7) The thermal efficiencyof the Rankine cyc ...

...

It is also interesting to note the thermal efficiency of a Carnot cycle oper- ating between the same temperature limits The diff ...

the steam in the boiler to compensate for these undesired heat losses. As a result, cycle efficiency decreases. Of particular im ...

EXAMPLE 10–2 An Actual Steam Power Cycle A steam power plant operates on the cycle shown in Fig. 10–5. If the isen- tropic effic ...

Turbine work output: Boiler heat input: Thus, (b) The power produced by this power plant is Discussion Without the irreversibili ...

To take advantage of the increased efficiencies at low pressures, the con- densers of steam power plants usually operate well be ...

Operating pressures of boilers have gradually increased over the years from about 2.7 MPa (400 psia) in 1922 to over 30 MPa (450 ...

Chapter 10 | 563 (a) This is the steam power plant discussed in Example 10–1, except that the condenser pressure is lowered to 1 ...

564 | Thermodynamics Therefore, the thermal efficiency increases from 33.4 to 37.3 percent as a result of superheating the steam ...

expansion process takes place in two stages. In the first stage (the high- pressure turbine), steam is expanded isentropically t ...

566 | Thermodynamics Tavg,reheat s T FIGURE 10–12 The average temperature at which heat is transferred during reheating increase ...

Chapter 10 | 567 Pump 3 6 Boiler Condenser 2 s T, °C 4 1 5 Reheater Reheating P 4 = P 5 = Preheat 15 MPa 10 kPa 10 kPa 15 MPa 15 ...

and Discussion This problem was solved in Example 10–3cfor the same pres- sure and temperature limits but without the reheat pro ...

sure (state 6). Some steam is extracted at this state and routed to the feed- water heater, while the remaining steam continues ...

where The thermal efficiency of the Rankine cycle increases as a result of regen- eration. This is because regeneration raises t ...

ture of the extracted steam because a temperature difference of at least a few degrees is required for any effective heat transf ...

572 | Thermodynamics Boiler Condenser s T 5 1 7 2 Pump II Turbine 1 4 7 6 3 4 3 2 1.2 MPa 1.2 MPa 6 10 kPa Pump I 10 kPa wturb,o ...

Chapter 10 | 573 State 3: State 4: State 5: State 6: State 7: The energy analysis of open feedwater heaters is identical to the ...

574 | Thermodynamics Discussion This problem was worked out in Example 10–3cfor the same pressure and temperature limits but wit ...