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Steam Motor Efficiency

  1. Mar 5, 2015 #1
    I am doing an experiment to determine the performance of a steam plant cycle and analyse it in comparison with the ideal rankine cycle.

    I have a sketch of the actual and real T-S diagram for the steam plant (See attached)

    I am unsure what factors cause the change in the shape of the T-S diagram. I understand that friction and heat loss will reduce the efficiency of the plant but how does this affect the shape of the graph?
     

    Attached Files:

  2. jcsd
  3. Mar 5, 2015 #2

    SteamKing

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    In a well-designed and well-maintained plant, friction and heat losses are minimized, but these wouldn't be included in the thermodynamic cycle diagrams anyway.

    The chief differences between the ideal Rankine cycle and the actual cycle are due to irreversibilities in the expansion of steam in the turbine and in the pumping losses from getting the condensate returned to the boiler to be turned back into steam. It takes more work to pump the condensate and less work is extracted from the turbine in the actual cycle than the ideal cycle.

    http://en.wikipedia.org/wiki/Rankine_cycle#Real_Rankine_cycle_.28non-ideal.29
     
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