Thermos Index

Thermodynamics-Turbine Vapour Cycle with Superheat on T-h Diagram


Steam cycle on Temp - Enthalpy Diagram

This cycle shows the stages of operation in a turbine plant with superheated steam.    The enthalpy reduction in the turbine is represented by F -> G .   The reversible process for an ideal isentropic (reversible adiabetic) is represented by F->G'.   This enthalpy loss would be (h g2 - h 2 ) in the reversible case this would be (h g2 - h 2s ).

The heat loss by heat transfer in the condenser is shown as G->C and results in a loss of enthalpy of (h2- hf2)or in the idealised reversible process it is shown by G'-> C with a loss of enthalpy of (h2s- hf2).

The work done on the water in extracting it from the condenser and feeding it to the boiler during adiabetic compression C-> D is (h d - h f2 ) = length M

The energy added to the working agent by heat transfer across the heat transfer surfaces in the boiler is (hg1 - hd ) which is approx.( h g1 - h f2 )

The Rankine efficiency of the Rankine Cycle AFG'CDEA is

The efficiency of the Real Cycle is



....More notes to follow....


Steam Turbine Links
  1. Wikipedia- Steam Turbines..A series of very informative notes and diagrams
  2. Steam Turbines..A one page article with very good graphics
  3. Technology Characterization Steam Turbine ..A downloadable paper including lots of useful relevant information
  4. Tpub-Steam Turbines ..Lots of useful Information and very nice sketches


Thermos Index