Camot cycle

In comparison the theoretical efficiency of a conventional combustion engine is limited by the Camot-cycle efficiency. This efficiency (Equation 6.5) is a function of the operating temperature (T2) and the temperature of the surroundings (Ti). 

Figure 6.3. Camot cycle temperature-volume diagram.

TABLE 6.1. Coupling of Two Camot Cycles with Different Efficiencies... 

The relationship between the thermodynamic temperature scale and the ideal gas temperature scale can be derived by calculating the thermodynamic quantities for a Camot cycle with an ideal gas as the working substance. Eor this purpose, we shall use 0 to represent the ideal gas temperamre. 

We can do this by examining the small Camot cycles in more detail. For example, for the cycle labeled a, we can state definitely, because the adiabatic steps contribute nothing to DQ/T, that... 

A better approximation to the actual cycle of Figure 6.5(a) would be a larger number of Camot cycles in Figure 6.5(h). In each such approximation. Equation (6.61) would be valid, but as the number of cycles used for the approximation is increased, the area BACB becomes smaller and smaller. In the limit of an... 

Figure 6.9. Gibbs temperature-entropy diagram for a Camot cycle.

Show that the efficiency of a Carnot cycle in which any step is carried out irreversibly cannot be greater than that of a reversible Camot cycle. 

Figure 4.3 Reversible Camot cycle, showing steps (1) reversible isothermal expansion at th (2) reversible adiabatic expansion and cooling from th to tc (3) reversible isothermal compression at tc (4) reversible adiabatic compression and heating back to the original starting point. The total area of the Camot cycle, P dV, is the net useful work w performed in the cyclic process (see text).

Figure 4.4 Reversible Camot cycle, shown in (a) PV diagram, (b) ST diagram.

The temperature-entropy diagram for the Camot cycle, corresponding to the pressure-volume diagram is shown in Fig. 2. 

Since a Camot engine is reversible, it may be operated in reverse the Camot cycle is then traversed in the opposite direction, and it becomes a reversible... 

With the improved C in hand, we can now envision operating the old Camot cycle as a heat pump C, then coupling this to C as shown in (4.15), using the heat output qh from heat pump C, to drive the improved heat engine C (i.e., with qh = ) ... 

In a Camot cycle (Fig. 13.5), a system traverses two isothermal and two adiabatic paths to return to its original state. Each path is carried out reversibly (that is, in thermal equilibrium, with internal and external forces nearly balanced at every step). As the system proceeds from state A to C through state B, the system performs work (Fig. 13.5a) ... 

In classical equilibrium thermodynamics, the simplest model of an engine that converts heat into work is the Camot cycle. The behavior of a heat engine working between two heat... 

O = K. This mirror O is, at this case, the direct Camot Cycle O as for its structure, but functioning in the indirect, reverse mode [6, 8]. 

Then, necessarily, the mirror, the reverse Camot Cycle O (the transfer channel K ) is to be constructed with that step-aside (excluding that stationarity) from the observed 0 = K. Now we mean that the step-aside of the observing process O from the observed process O is realized by the difference Tw-T w >0. Now, within this thermodynamic point of view, it is valid that... 

Then we need a mirror, the reverse Camot Cycle O =T (or the relevant transfer channel K ) would be constructed in such a way that the mentioned step-aside from the observed transfer channel K was respected. [It is the step-aside of the observing process (O, T) from the observed process (O, 7) also we can consider a computing process k and its description -the program rj, and its observation, see later]. 

It is valid, for AA is a residuum work after the work A A has been performed at the temperature Tw- Evidently, the sense of the symbol T w (within the double cycle OO and when AQ0=AQ o) is expressible by the symbol 7 0", which is possible, for the working temperatures of the whole cycle OO are Tw and T "w = 7 0". The relation (30) expresses that fact that the double cycle OO is the direct Camot Cycle just with its working temperatures TW>T =7 0". In the double cycle OO it is valid that... 

The COP in real refrigeration cycles is always less than for the ideal (Camot) cycle and there is constant effort to achieve this ideal valne. 

The next step is the conversion of the thermal energy of the steam to the mechanical energy of a turbine. The efficiency of this step is limited by absolute thermodynamic constraints as described classically through an ideal heat cycle such as the Camot cycle. 

The Camot cycle is formulated directly from the second law of thermodynamics. It is a perfectly reversible, adiabatic cycle consisting of two constant entropy processes and two constant temperature processes. It defines the ultimate efficiency for any process operating between two temperatures. The coefficient of performance (COP) of the reverse Camot cycle (refrigerator) is expressed as... 

Rankine Cycle Thermodynamics, Carnot cycles provide the highest theoretical efficiency possible, but these are entirely gas phase. A drawback to a Camot cycle is the need for gas compression. Producing efficient, laige-volume compressors has been such a problem that combustion turbines and jet engines were not practical until the late 1940s. 

Nicolas Leonard Sadi Carnot, the French engineer and physicist, was bom in Paris in 1796. His father, Lazare Nicolas Marguerite Carnot, was in the French military service. Sadi Camot is considered as the founder of modem thermodynamics. Famous for his invaluable contributions to science and thermodynamics, Sadi Camot was honored with the title Father of Thermodynamics. Some of his noteworthy contributions to thermodynamics are the concepts of Camot heat engine, Camot cycle, Carnot s theorem, Camot efficiency, and reversible cycle. 

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