Carnot ideal heat engine

Although the Carnot cycle is useful in determining the ideal behavior of an ideal heat engine, it is not a practical cycle to use in the design of heat... 

A hypothetical cycle for achieving reversible work, typically consisting of a sequence of operations (1) isothermal expansion of an ideal gas at a temperature T2 (2) adiabatic expansion from T2 to Ti (3) isothermal compression at temperature Ti and (4) adiabatic compression from Ti to T2. This cycle represents the action of an ideal heat engine, one exhibiting maximum thermal efficiency. Inferences drawn from thermodynamic consideration of Carnot cycles have advanced our understanding about the thermodynamics of chemical systems. See Carnot s Theorem Efficiency Thermodynamics... 

In Chapter 5 we said that Carnot s classic model of an idealized heat engine resulted in the following properties of the entropy function ... 

Carnot Cycle - An ideal heat engine (conceived by Sadi Carnot) in which the sequence of operations forming the working cycle consists of isothermal expansion, adiabatic expansion, isothermal compression, and adiabatic compression back to its initial state. 

Sadi Carnot s most valuable contribution to thermodynamics is Carnot s ideal heat engine operating with Carnot cycle. His works on ideal heat engine provided the foundation for quantitative mathematical formulation of Carnot efficiency based on Carnot s theorem. However, Carnot s research findings were not well known until another scientist Benoit Pierre Emile Clapeyron followed in his footsteps and experimented with the change in pressure and volume of the processes of a cycle and its effect on work done. Clapeyron developed Carnot s idea of the efficiency of... 

The most elRcient means of converting thermal energy into work or electricity is the Carnot cycle. The Carnot cycle represents an idealized heat engine that is unachievable in practical systems but that sets a useful standard for heat engine performance and comparisons. The Carnot elRciency is given by... 

Keep in mind that a Carnot engine operates reversibly between two heat reservoirs. The expression of Eq. 4.3.14 gives the efficiency of this kind of idealized heat engine only. If any part of the cycle is carried out irreversibly, dissipation of mechanical energy will cause the efficiency to be lower than the theoretical value given by Eq. 4.3.14. 

The Carnot efficiency relates theworkiynecessary to pump an amount of heat energy Q from a low-temperature heat source at temperature to a higher-temperature heat sink at temperature Tjj, by use of an ideal heat engine. This is ... 

Carnot s work aimed at clarifying, among other things, how large a proportion of the supplied heat could be transformed into mechanical useful work in an ideal heat engine. This can be expressed by the thermal efficiency of the machine, defined in the following way... 

Carnot s cycle A hypothetical scheme for an ideal heat machine. Shows that the maximum efficiency for the conversion of heat into work depends only on the two temperatures between which the heat engine works, and not at all on the nature of the substance employed. 

Heat engines for conversion of solar energy to electric power ideally should have lhe following attributes (1) low cost per kilowatt output capacity (2) long life and reliable operation with minimal maintenance (3) safe and environmentally acceptable operation (4) characteristics compatible with cycle top temperatures up to 1,000 K and (5) efficiency approaching Carnot values. 

We prove the identity of the Kelvin scale and the ideal gas scale by using an ideal gas as the fluid in a reversible heat engine operating in a Carnot cycle between the temperatures T2 and 7. An ideal gas has been defined by Equations (2.36) and (2.37). Then the energy of an ideal gas depends upon the temperature alone, and is independent of the volume. 

In Chapter 2, we have analyzed one particular type of heat engine, the reversible Carnot cycle engine with an ideal gas as the working substance, and found that its efficiency is e = 1 — Tc/Th. For both practical and theoretical reasons, we ask if it is possible, with the same two heat reservoirs, to design an engine that achieves a higher efficiency than the reversible Carnot cycle, ideal gas engine. What can thermodynamics tell us about this possibility ... 

Students are reminded of the upper thermodynamic limit set on the efficiency of a heat engine, for example the internal combustion and gas-turbine engines. The ideal and totally unrealistic engine would operate on the so-called Carnot cycle where the working substance (e.g. the gas) is taken in at the high temperature (Th) and pressure and after doing external work is exhausted at the lower temperature (Tc) and lower pressure. The Carnot efficiency, /, is given by... 

Thus, we can see that heat engines can be conceived with not only system of an ideal gas but also with systems involving physical and chemical changes. And Carnot s Theorem (2nd Law) holds for all such examples. 

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