Table of Contents
- 1 Why is Carnot cycle not practical?
- 2 Why the Rankine cycle is preferred over the Carnot cycle in steam power plants?
- 3 Which cycle is used in steam power plant?
- 4 Why is 100 efficiency impossible?
- 5 Why is Rankine cycle considered as the most practical cycle?
- 6 Why is the Carnot cycle not used in power plants?
- 7 Why is the Carnot cycle an idealization of the heat engine cycle?
- 8 Why is a constant pressure process used in the Rankine cycle?
Why is Carnot cycle not practical?
The conceptual value of the Carnot cycle is that it establishes the maximum possible efficiency for an engine cycle operating between TH and TC. It is not a practical engine cycle because the heat transfer into the engine in the isothermal process is too slow to be of practical value.
Why the Rankine cycle is preferred over the Carnot cycle in steam power plants?
Carnot cycle is an ideal cycle for heat engine which gives highest efficiency between given temperature difference but it is a theoretical cycle and actually no engine works on it. Rankine cycle is an ideal cycle of vapor or steam power generation. It gives highest efficiency between given temperature difference.
Why is Rankine cycle considered most practical cycle?
Rankine cycle is considered as most practical cycle because of the complete condensation of the steam in the condenser.
Which cycle is used in steam power plant?
steam Rankine cycle
The steam Rankine cycle is one of the highest utilized types of thermodynamic cycles for electricity production in the world [1]. The steam power stations run on Rankine cycles using steam as a working fluid. The simple ideal Rankine cycle is in fact the most basic vapor power cycle.
Why is 100 efficiency impossible?
No machine is free from the effects of gravity, and even with wonderful lubrication, friction always exists. The energy a machine produces is always less than the energy put into it (energy input). That is why 100\% efficiency in machines shall not be possible.
What is the efficiency of Carnot cycle?
POWER GENERATION SYSTEMS EVALUATED
| ID | Fuel | CO2 Sequestration Technology |
|---|---|---|
| PN2 | Coal | None |
| PN3 | Coal | MEA SCRUBBER |
| PN4 | Coal | O2 FIRING |
| PN5 | Coal | None |
Why is Rankine cycle considered as the most practical cycle?
The efficiency of the Rankine cycle is limited by the high heat of vaporization by the fluid. The fluid must be cycled through and reused constantly, therefore, water is the most practical fluid for this cycle. This means the pump requires less work to compress the water—resulting in higher overall efficiencies.
Why is the Carnot cycle not used in power plants?
There are three reasons for the carnot cycle not being used in power plants: Firstly, carnot cycle involves transition from an isothermal process to an adiabatic process. The heat exchange in carnot cycle is isothermal which needs the working fluid to either phase change or the process be extremely slow.
Which is the best cycle for steam power plant?
However ideal cycle for steam power plant is Rankine cycle. Carnot Vapour cycle is not suitable for steam power plant because in Carnot Vapour cycle at the end of condensation process we get a two phase mixture and next is the compression process where it is impossible to compress a mixture in two phase.
Why is the Carnot cycle an idealization of the heat engine cycle?
In order to approach the Carnot efficiency, the processes involved in the heat engine cycle must be reversible and involve no change in entropy. This means that the Carnot cycle is an idealization, since no real engine processes are reversible and all real physical processes involve some increase in entropy.
Why is a constant pressure process used in the Rankine cycle?
The heat exchange in carnot cycle is isothermal which needs the working fluid to either phase change or the process be extremely slow. Thus constant pressure process is used in rankine cycle. In rankine cycle,the pumping losses are less because the pumping starts at saturated water condition which is eqsy to pump.