Abstract
Chemically nonequilibrium flows with allowance for vibrational relaxation are investigated numerically within the framework of the hypersonic viscous shock layer equations with reference to the example of the flow in the neighborhood of the critical line of the “Buran” orbital vehicle in its motion along a re-entry trajectory. It is found that the vibrational temperatures of the molecular components differ markedly. The distinctive feature of the model in question, as compared with a model with one average vibrational temperature, is the stronger effect on the flow characteristics over the thermally stressed part of the trajectory. The models proposed in the literature for dissociation from an effective vibrational level are compared with the model for dissociation with a certain probability from all the vibrational levels. It is shown that the use of an approximation of the total dissociation constant as a function of translational temperature only may lead to a considerable variation from the results of calculations with allowance for vibrational relaxation on the basis of the equilibrium dissociation rate constant.
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Additional information
Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 2, pp. 138–146, March–April, 1994.
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Shcherbak, V.G. Comparison of different approaches to the calculation of chemically nonequilibrium flow with allowance for vibrational relaxation. Fluid Dyn 29, 263–269 (1994). https://doi.org/10.1007/BF02324318
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DOI: https://doi.org/10.1007/BF02324318