Variational Principles for Stellar Structure
نویسنده
چکیده
The four equations of stellar structure are reformulated as two alternate pairs of variational principles. Different thermodynamic representations lead to the same hydromechanical equations, but the thermal equations require, not the entropy, but the temperature as the thermal field variable. Our treatment emphasizes the hydrostatic energy and the entropy production rate of luminosity produced and transported. The conceptual and calculational advantages of integral over differential formulations of stellar structure are discussed along with the difficulties in describing stellar chemical evolution by variational principles. Subject headings: Stellar structure and evolution; variational principles; non-equilibrium thermodynamics Published in the Astrophysical Journal: 20 July 1997
منابع مشابه
VARIATIONAL PRINCIPLES FOR STELLAR STRUCTURE Dallas
The four equations of stellar structure are reformulated as two alternate pairs of variational principles. Different thermodynamic representations lead to the same hydromechanical equations, but the thermal equations require, not the entropy, but the temperature as the thermal field variable. Our treatment emphasizes the hydrostatic energy and the entropy production rate of luminosity produced ...
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