Page 354 - Steam Turbines Design, Applications, and Rerating
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328   Chapter Fifteen

              If all staging is of the Rateau type in this portion of the turbine:

                                  V j = 215/0.46 = 467 m/s

            ΔH i per stage is therefore:
                                     2        2
                                   Vj     467
                            ΔH i =      =       = 109.0 kJ/kg
                                  2000    2000
            The number of Rateau stages in this section would therefore be:

                        Total energy available    832
                                               =        = 7.7 (say 8)
                      Energy removed per stage    109.0

              The turbine will, therefore, contain one 635-mm diameter Curtis
            stage followed by eight 890-mm-diameter Rateau stages with the
            extraction opening after the Curtis stage.
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