Hybrid Thermofluid Modeling with LTE and non-LTE Assumption for Decaying Molecular Gas Arcs

A hybrid simulation model for SF
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arcs in decaying phase was developed with the two-temperature chemically non-equilibrium (2T-CNE) model and the chemical equilibrium (2T-CE) model. We previously developed the full 2T-CNE model for the whole calculation space, which needs a long computation time. The developed hybrid model in the present work comprises the 2T-CNE model for decaying arcs in a region with a specified temperature range, whereas the CE model is adopted in the calculation space except the above specified region. The criterion on heavy-particle temperature range for chemical non-equilibrium calculation in the hybrid 2T-CNE model was also studied to get the distribution of temperature and those of each of species almost equal to those by the full 2T-CNE model. As a result, the developed 2T-CNE hybrid simulation model for CNE calculation for heavy-particle temperatures above 1000 K was found to be useful to simulate gas flow, temperature and chemical fields in decaying SF
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arcs in spite of a partial consideration of chemically non-equilibrium effects.