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Gas-dynamic equations involving vibrational relaxation

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We derive the gas-dynamic equations in the Navier-Stokes approximation for weak excitation of molecular vibrational states. We determine the distribution function for the density of the numbers determining occupancy of the vibrational states of the molecules. We show that the relaxational pressure is proportional to the deviation of the vibrational energy density from its local-equilibrium value for the temperature of the translational and rotational degrees of freedom of the molecules.

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Translated from Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki, No. 4, pp. 8–17, July–August, 1972.

In conclusion, the author thanks V. N. Zhigulev and V. S. Galkin for a discussion of his results.

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Pal'tsev, L.A. Gas-dynamic equations involving vibrational relaxation. J Appl Mech Tech Phys 13, 437–445 (1972). https://doi.org/10.1007/BF00850382

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