Page 147 - Advanced Thermodynamics for Engineers, Second Edition
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134    CHAPTER 6 FINITE TIME (OR ENDOREVERSIBLE) THERMODYNAMICS




                                                   exhaust gas

                                                 6      High temperature
                                                        heat exchanger
                                           2
                                                       3

                                                   5
                                                               Turbine
                                    2                        3
                                      Compressor
                                                   5
                                  1                     4         4  Generator
                                 Intake
                                  air                   Fuel
                                                Burner

             FIGURE 6.10
             Arrangement for a gas turbine to use biofuel by indirect combustor.



                                                               T Hin
                                Temperature, T     T Hout  3        5






                                                           4


                                                         4 S S S
                                         2
                                     2 S                  T Lout
                                                    6



                                       1
                                           T Lin

                                                                    Entropy, S
             FIGURE 6.11
             Temperature-entropy diagram for the system shown in Fig. 6.10.
             combustion process with biomass fuel to the highest temperature point of the cycle, i.e. state 5. The hot
             gas exits the combustion chamber and enters the HTHE, where it adds energy to the air by cooling to
             state 6 at constant pressure. In Fig. 6.11, the process 1-2s is an isentropic compression and the actual
             process 1-2 takes into account the non-isentropic nature of a real compressor; the process 3-4s is an
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