Influence of operational parameters on the statistics of thermal field in low Damkohler reaction zones

The fluctuating temperature field in a jet stirred flow reactor designed fu r chemical kinetic studies of hydrocarbon oxidation is investigated. In ord er to address both the question of the degree of micromixing and that of th e turbulence/chemistry interaction, the present paper analyses and compares the fluctuating temperature structures inside this rc:actor for various si tuations. The experimental study is conducted by thr technique of fine-wire thermoanemometry. The pdfs, spectra and the relevant time scales of the te mperature field are determined. In parallel, the fuel conversion rates of p ropane oxidation in all the experimental conditions are determined fi om a simulation work which takes into account a detailed kinetic model previousl y established. The variation of the unmixedness and the time scales of the temperature field is compared for a wide range of parameters in the reactin g and non-reacting cases. The discussion is conducted in terms of the ratio between the time scales of the scalar and dynamic fields and of a Damkohle r number.