Variational Formulations and Extended Thermodynamics for Resting Irreversible Fluids with Heat Flow
نویسنده
چکیده
Nonequilibrium statistical mechanics helps to estimate corrections to the entropy and energy of the fluid with heat flux in terms of the nonequilibrium distribution function, f. This leads to the coefficients of wave model of heat: relaxation time, propagation speed and thermal inertia. With these data a quadratic Lagrangian and a variational principle of Hamilton’s type follows for the fluid in the field representation of fluid’s motion. We analyze canonical conservation laws and show the satisfaction of the second law under the constraint of these conservation laws. Key-Words: Grad solution, variational calculus, wave equations, conservation laws, entropy.
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