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SSSF Analysis of Devices Used in Power Generation - 1. P M V Subbarao Professor Mechanical Engineering Department. Sources of Work for Manufacturing Industry …. Thermal Structure of Power Generation System. Options for Power Plants. Shaft Power Generation Systems.
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SSSF Analysis of Devices Used in Power Generation - 1 P M V Subbarao Professor Mechanical Engineering Department Sources of Work for Manufacturing Industry …..
Options for Power Plants • Shaft Power Generation Systems
The first Step in Innovation of A Power Plant p=constant p=constant Rankine Cycle Brayton Cycle Process 1 2 Adiabatic compression Process 2 3 Constant pressure heat addition Process 3 4 Isentropic expansion Process 4 1 Adiabatic Pressure heat rejection
Selection of Fluids : Thermodynamics • The selection of working fluids and operational variables is very important to obtain better system performance. • The thermodynamic properties of working fluids will affect the system efficiency, operation, and environmental impact. • Fluid must be selected in accordance to the temperature level of the heat source. • Minimum temperature difference between the source and working fluid during heat addition (pinch point) is limiting factor for heat transfer
Candidate Working Substances for Rankine Cycle Working Substances must be selected in accordance to the heat source temperature level (Tcr < Tin-source)
Selection of Fluids : Ecology • Environmental impacts and restrictions by using organic substances • Inflamable and/or toxic and/or GWP (Global Warming Potential) and/or ODP • (Ozone Depletion Potential)
List of CVs • Main components of the above cycle are: • 1) Pump – Generate high Pressure water. • 2) Boiler (steam generator) – heat exchanger • 3) Turbine – generates mechanical power • 4) Condenser – heat exchanger • Others components include: • nozzles, diffusers, throttling devices Each one of these CVs carryout a specific process continuously at almost SSSF. However, The plant operates in a Cycle.
Pump : Adiabatic Process 1 2 SSSF: Conservation of mass First Law : No heat transfer, change in kinetic and potential energies are negligible
For SSSF Process: Liquids are incompressible, change in volume per unit change in Pressure is negligible.
Pumping of Incompressible Fluids Adiabatic pumping of a liquid is almost an Isothermal process!!