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arXiv · 1802.03036

A new jet-stirred reactor for chemical kinetics investigations

Abbasali A. Davani·Paul D. Ronney
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Abstract

A novel jet-stirred reactor was designed to study combustion processes at low Damk\"ohler number (Da, ratio of residence time to chemical time), i.e. chemical kinetics. In this new design, multiple impinging turbulent jets are used to stir the mixture. The goal of this work is to identify an optimal configuration of multiple pairs of impinging jets and outlet ports for as a Jet-Stirred Reactor (JSR) for chemical kinetics experiments. With this motivation, ANSYS-FLUENT computations using the RANS - Reynolds Stress Model were used to simulate mixing and reaction in such geometries and their performance was compared to classical JSR (4 Jets In Plus (+) Pattern (4JIPP) introduced by Matras & Villermaux 1973; Dagaut et al. 1986; etc.). Results showed that a configuration of 8 jets, each surrounded by a concentric annular outlet (CIAO), at the corners of an imaginary cube circumscribed by a spherical chamber provided far more uniform composition and temperature and thereby more nearly match the idealizations assumed in well-stirred reactor theory, even at values of Da higher than those accessible to other JSR experiments. Moreover, the CIAO design yielded inferred reaction rate constants that were much to the actual values than the classical JSR design.

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Abbasali A. Davani, Paul D. Ronney. 2018-02-08. A new jet-stirred reactor for chemical kinetics investigations. https://arxiv.org/abs/1802.03036

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