SOLUTION

The Rankine cycle is a model used to predict the performance of steam turbine systems. It was also used to study the performance of reciprocating steam engines. The Rankine cycle is an idealized thermodynamic cycle of a heat engine that converts heat into mechanical work while undergoing the phase change. The heat is supplied externally to a closed loop, which usually uses water as the working fluid. It is named after William John Macquorn Rankine, a Scottish polymath and Glasgow University professor.

Power depends on the temperature difference between a heat source and a cold source. The higher the difference, the more mechanical power can be efficiently extracted out of heat energy, as per Carnot’s theorem.

The heat sources used in these power plants are usually nuclear fission or the combustion of fossil fuels such as coal, natural gas, and oil, or concentrated solar power. The higher the temperature, the better.

Principal Components of Vapour Power Plant

The four basic components of a vapor power plant are shown in Fig. Each component in the cycle is regarded as a control volume, operating at steady state.

1. Boiler:-  The heat is supplied to the working fluid (feed water) in the boiler and thus vapor is generated. The vapor leaving the boiler is either saturated or superheated depending upon the amount of heat supplied into the boiler.
2. Turbine: The vapor leaving the boiler enters the turbine, where it expands isentropically to the condenser pressure. The work produced by the turbine is rotary (shaft) work and is used to drive an electric generator or machine.
3. Condenser: The condenser is attached at the exit of the turbine. The vapor leaving the turbine is wet vapor and it is condensed completely in the condenser, by giving its latent heat to some other cooling fluid like water.
4. Pump:- The liquid condensate leaving the condenser is pumped to the operating pressure of the boiler. The pump operation is considered is entropic.

Brayton Cycle:- The Brayton cycle is the ideal cycle for gas-turbine engines. Today, it is used for the gas turbine in which both the compression and expansion processes are implemented such as the jet engine.

Stirling cycle:- Stirling engine is used in some submarines because this engine produces very less noise thus serving its purpose for the submarine which is used for secret purposes. it is also used in automobile, aircraft engines, pump engine etc.

Carnot cycle:- Carnot engine is a theoretical cycle. It is used for analytical and more importantly reference purposes only.