An exploration for the macroscopic physical meaning of entropy
Tóm tắt
The macroscopic physical meaning of entropy is analyzed based on the exergy (availability) of a combined system (a closed system and its environment), which is the maximum amount of useful work obtainable from the system and the environment as the system is brought into equilibrium with the environment. The process the system experiences can be divided in two sequent sub-processes, the process at constant volume, which represents the heat interaction of the system with the environment, and the adiabatic process, which represents the work interaction of the system with the environment. It is shown that the macroscopic physical meaning of entropy is a measure of the unavailable energy of a closed system for doing useful work through heat interaction. This statement is more precise than those reported in prior literature. The unavailability function of a closed system can be defined as T
0
S and p
0
V in volume constant process and adiabatic process, respectively. Their changes, that is, Δ(T
0
S) and Δ(p
0
V) represent the unusable parts of the internal energy of a closed system for doing useful work in corresponding processes. Finally, the relation between Clausius entropy and Boltzmann entropy is discussed based on the comparison of their expressions for absolute entropy.
Tài liệu tham khảo
Shannon C E. A mathematical theory of communication. Bell Syst Tech J, 1948, 27: 379–423, 623–656
Georgescu-Roegen N. The Entropy Law and the Economic Process. Cambridge: Harvard University Press, 1971. 125–142
Feng D, Feng S T. The World of Entropy (in Chinese). Beijing: Science Press, 2005. 1
Harken H. Synergy: Theory and Application (in Chinese). Beijing: China Science and Technology Press, 1990. 259
Prigogine I. What is entropy? Naturwissenschaften, 1989, 76: 1–8
Tribus M, Mclrvine E C. Energy and information. Sei Am, 1971, 225: 179–184
Moran M J. Availability Analysis: A Guide to Efficient Energy Use. New Jersey: Prentice-Hall, Inc., 1982. 46: 4–8
Liu G Y, Liu Z G, Yin J M, et al. Engineering Thermodynamics (in Chinese). Beijing: Higher Education Press, 1998. 132, 147–149
Safire W. The New York Times Guide to Essential Knowledge. 2nd ed. London: Macmillan, 2007. 369
Martin E, Hine R S. A Dictionary of Biology. 4th ed. Oxford: Oxford University Press, 2000. 208
Kirwan A D. Mother Nature’s Two Laws. New Jersey: World Scientific, 2000. 37–39
Simpson J A, Weiner ESC. The Oxford English Dictionary: vol. V. 2nd ed. Oxford: Clarendon Press, 1989. 308
Rajput R K. Engineering Thermodynamics. 3rd ed. Sudbury, MA: Jones & Bartlett Publishers, 2009. 314–315