In real engines, the heat transfers at a sudden change in temperature whereas in a Carnot engine, the temperature remains constant. In our day to day lives, reversible processes can’t be carried out and there is no such engine with 100 % efficiency. Thus, the Carnot cycle is practically not possible.
Why is Carnot engine Impossible?
Because the Carnot cycle consist of Isothermal process which is not possible to achieve in reality. The perfect Isothermal requires temperature of the system to be constant irrespective of increase in pressure and decrease in volume. Carnot cycle is ideal cycle in nature.
Is a Carnot engine possible?
Any engine using the Carnot cycle, which uses only reversible processes (adiabatic and isothermal), is known as a Carnot engine. Any engine that uses the Carnot cycle enjoys the maximum theoretical efficiency. … Carnot cycles without heat loss may be possible at absolute zero, but this has never been seen in nature.
Why Carnot refrigerator is not possible?
This is because that the isentropic process of Carnot cycle requires a high speed of air while the isothermal process of Carnot cycle requires extremely slower speed. … This large variation in speed of air is simply not possible.
What are the limitations of Carnot engine?
The higher the temperature of the low- temperature sink, the more difficult for a heat engine to transfer heat into it. Thus, lower thermal efficiency also. 16. LIMITATIONS OF CARNOT CYCLE The isentropic process 1-2 is practically not achievable,as it is difficult to handle two phase system.
Why 100% efficiency is not possible?
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.
Why 100 efficient engine is not possible?
A heat engine is considered to be 100% efficient if only all the heat is converted into useful work or mechanical energy. … Since heat engines cannot convert all the heat energy into mechanical energy, their efficiency can never be 100%.
Are all reversible engines Carnot engines?
The same proof can be run through with the reversible engine as more efficient and again there is a violation. This means all reversible engines are of the same efficiency as Carnot engines.
Why does the Carnot heat engine not exist in practice give any four points?
A Carnot engine has to be perfectly reversible. This means zero friction, and perfect thermal conductivity between reservoirs*. In practice neither of these things are possible so you will only ever get “close”.
Why is Carnot cycle not used in steam power plant?
However; the Carnot cycle is not a suitable model for steam power cycle since: The turbine has to handle steam with low quality which will cause erosion and wear in turbine blades. … Thus, the Carnot cycle cannot be approximated in actual devices and is not a realistic model for vapor power cycles.
Is reverse Carnot cycle possible?
Reversed Carnot Cycle
Carnot cycle is a totally reversible cycle which consists of two reversible isothermal processes and two isentropic processes. It has the maximum efficiency for a given temperature limit. Since it is a reversible cycle, all four processes can be reversed.
What are the limitations of a Carnot cycle for refrigeration?
Limitations of Carnot cycle:
This is difficult to achieve in practice. In addition, the volumetric refrigeration capacity of the Carnot system is very small leading to large compressor displacement, which gives rise to large frictional effects.
What are the challenges for Carnot refrigeration cycle?
Practical difficulties with Carnot refrigeration system:
Such variation of speed in a stroke is not possible and makes it impracticable. With finite specific heats of a medium, it is not possible to carry out isothermal heat transfer process in practice.
What is the Carnot efficiency of a heat engine?
The Carnot Efficiency is the theoretical maximum efficiency one can get when the heat engine is operating between two temperatures: The temperature at which the high temperature reservoir operates ( THot ). The temperature at which the low temperature reservoir operates ( TCold ).