Rankine cycle is considered as most practical cycle because of the complete condensation of the steam in the condenser.

How does a practical Rankine cycle differs from an ideal Rankine cycle?

The actual vapor cycle differs from the ideal Rankine Cycle as a result of irreversibility in various components. Two major factors of irreversibility are Fluid friction and heat loss.

Why should a Rankine cycle be considered an ideal cycle for steam power plants?

The efficiency of the Rankine cycle is limited by the high heat of vaporization of the working fluid. ... This low steam turbine entry temperature (compared to a gas turbine) is why the Rankine (steam) cycle is often used as a bottoming cycle to recover otherwise rejected heat in combined-cycle gas turbine power stations.

Why is the Rankine cycle used?

Rankine cycle, in heat engines, ideal cyclical sequence of changes of pressure and temperature of a fluid, such as water, used in an engine, such as a steam engine. It is used as a thermodynamic standard for rating the performance of steam power plants.

What is the reason behind the fact that the ideal regenerative cycle is practically not possible?

The ideal regenerative cycle is not practically possible because a heat exchanger cannot be installed inside the turbine as there are more chances for the erosion of the turbine blade (last stage). The thermal efficiency of the ideal regenerative cycle is equal to that of the Carnot cycle.

RANKINE CYCLE (Simple and Basic)

What process does Rankine cycle contain?

Explanation: Working fluid in Rankine cycle undergoes 4 processes, expansion in turbine, heat addition in Boiler, heat rejection in Condenser and compression in pump.

Why does the efficiency of Rankine cycle increase as a result of regeneration?

Thermal efficiency of the Rankine cycle increases as a result of regeneration since FWH raises the average temperature of the water before it enters the boiler.

What is critical point in Rankine cycle?

The critical point is where the temper- ature and pressure are such that the fluid is no longer classified exclusive- ly as liquid or gas. It is thought of as a fluid above the critical point. The criti- cal point for water is slightly above 3200 psi.

What is Rankine based on?

The Rankine scale is a thermodynamic (absolute) temperature scale. It is based around absolute zero. Rankine is similar to the Kelvin scale in that it starts at absolute zero and 0 °Ra is the same as 0 K but is different as a change of 1 °Ra is the same as a change of 1 °F (Fahrenheit) and not 1 °C (Celsius).

What is the relation of Rankine cycle in term of steam turbine?

In the Rankine cycle, steam is created in a boiler, and part of the enthalpy of the high-pressure superheated steam is converted to shaft work in a steam turbine that drives an electric generator.

What is meant by Rankine cycle?

The Rankine cycle, also called the Rankine vapor cycle, is a thermodynamic cycle that converts heat into mechanical energy. The Rankine cycle is name after William Johnson Macquorn Rankine, a 19th century Scottish engineer and physicist known for his research in the thermodynamic properties of steam.

What is the difference between Rankine cycle and Brayton cycle Mcq?

Explanation: The difference between a Rankine cycle & a Brayton cycle is that the working fluid in a Brayton cycle doesn't undergo phase change while it does in Rankine cycle.

Why efficiency of Rankine cycle is less than Carnot cycle?

The thermal efficiency of a Rankine cycle is lower then that of a Carnot cycle operating between the same temperature levels. This is primarily because of the fact that the energy transfer as heat in the boiler does not take place at constant temperature in the Rankine cycle.

What type of process is the ideal Rankine cycle Mcq?

Explanation: Ideal Rankine Cycle is a reversible process. Explanation: For analytical purposes, always steady flow operation is considered, as in unsteady flow, the various fluid properties vary considerably which remain same when the steady flow operation is assumed.

What is organic Rankine cycle power generation?

Organic Rankine Cycle (ORC) systems are used for power production from low to medium temperature heat sources in the range of 80 to 350 °C and for small-medium applications at any temperature level. This technology allows for exploitation of low-grade heat that otherwise would be wasted.

What is the meaning of Rankine?

: being, according to, or relating to an absolute-temperature scale on which the unit of measurement equals a Fahrenheit degree and on which the freezing point of water is 491.67° and the boiling point 671.67°

What will be the Rankine cycle efficiency of a good steam power plant?

In a good steam power plant, the Rankine cycle efficiency varies from 35 to 45 %.

What is regeneration in Rankine cycle?

Regeneration: Regeneration, a process during which heat is transferred to a thermal energy storage device (called a regenerator) during one part of the cycle and is transferred back to the working fluid during another part of the cycle.

What pump is used in Rankine cycle?

The Rankine cycle operates in the following steps: 1-2-3 Isobaric Heat Transfer. High pressure liquid enters the boiler from the feed pump (1) and is heated to the saturation temperature (2). Further addition of energy causes evaporation of the liquid until it is fully converted to saturated steam (3).

Is the Rankine cycle a closed system?

A Rankine cycle is a closed-cycle system where a working fluid circulates through a minimum of an evaporator, turbine, condenser and a pump to convert heat into work, Figure 1. The conventional working fluid for Rankine cycle plants is water. ...

What is the purpose of reheating and regeneration in Rankine cycle?

Reheating of steam improved the thermal efficiency of the plant, net work output of turbine, reduction in blade erosion (or quality of steam improve). By regeneration thermal efficiency of the plant can be increased but it does not affect work output from turbine.

What is the effect of reheating on Rankine cycle?

Reheating is a method of improving Rankine cycle efficiency which consists of inter-stage heating of the expanding steam. After the first stage of expansion which typically reduces initial steam pressure by one-fourth, the steam is heated up (or close) to the maximum heat source temperature.

What are the advantages and disadvantages of regenerative cycle over simple Rankine cycle?

The thermal efficiency is improved because average temperature of heat addition to the cycle is increased. The Heating rate is reduced. The LP turbine blade height can be reduced because steam flow at lower stage is reduced. The steam condenser size can be reduced.

Why is Rankine cycle considered most practical cycle Mcq?

Higher efficiency during the regeneration process in 'Rankine cycle' is because of: Heat is added before steam enters the low-pressure turbine. The average temperature of heat addition in the boiler increases.

What are the four processes of Rankine cycle?

• Process 1-2: Isentropic compression in a pump. Here the working fluid is pumped from low to high pressure.
• 2-3: Constant pressure heat addition in the boiler. ...
• 3-4: Isentropic expansion in a turbine. ...
• 4-1: Constant pressure heat rejection in a condenser.