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Further Analysis of Irreversible Processes. P M V Subbarao Professor Mechanical Engineering Department. Other Methods to Account the Entropy Generation…. Process Efficiency of A Turbine.
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Further Analysis of Irreversible Processes P M V Subbarao Professor Mechanical Engineering Department Other Methods to Account the Entropy Generation…..
Process Efficiency of A Turbine • A turbine following a Reversible process will produce maximum work output using high enthalpy steam/gas. • Irreversible or actual turbine generates relatively lower magnitude of benefits. • The level of this process irreversibility is also defined as efficiency of a process or machine.
Quantification of Irreversibilities in Turbine (Power Generating Machine) pinlet Ideal work ws = hin – herev Actual work wa = hin – heirr h pExit s
Isentropic Efficiency of a Turbine • Isentropic efficiency is defined for an irreversible process. • This is the ratio of actual performance to Isentropic performance of a machine. • For power generation machines: • Isentropic efficiency = Actual power output/Isentropic power output. These definitions are case dependent and a separate definition is to be developed for each application.
ea Power Consuming Device Irreversible compressor: intake es h exit s i Isentropic(Reversible) work input | wiso| = hes-hi Irreversible work input |wact| = hea-hi For Power consuming machines: Isentropic efficiency = Isentropic power input/Actual Power input. Isentropic Efficiency of compressor
A Generalized Model Of A Manufacturing System Creation of Energy Sources for Manufacturing System Manufacturing System Material Processing System Creation of Energy Sources for Material Processing System
Alternate Generalized Model Of A Manufacturing System Material Processing System Manufacturing System
Power Plant for A Manufacturing System & Material Processing System Power Plant for Manufacturing System & Material Processing System
Heat Source for A Manufacturing System & Material Processing System Heat Generation Unit for Manufacturing System & Material Processing System
Model Equations for Generalized Manufacturing System • Conservation of mass: • First Law • Entropy Balance: