| Due to its better environmental friendliness and outstanding oxidability, ozonehas been widely utilized in water treatment and pharmaceuticals industry. In thispaper, density normalized effective ionization coefficients, electron energydistribution function and drift velocity are all calculated. The streamer breakdownmechanism is introduced to predict the breakdown voltage in ozonizers. Experimentalresults are also plotted for the sake of comparison. In addition, the influence of inertgases on ozone generation is analyzed taking the ozone formation path into account.Results are as follow.(1) In this work, density normalized effective ionization coefficients, electronenergy distribution function, mean electron energy and drift velocity are all calculatedusing Boltzmann equation along with two-term approximation in SF6-Air and SF6-O2mixtures over the range of reduced filed strength from40to500Td. The criticalelectric field strength is obtained at which the ionization and attachment rate areexactly balanced. Results show that SF6addition would lead to increasing meanelectron energy. The drift velocity increases with the increasing reduced field strengthand decreasing SF6content. Moreover, the effective ionization coefficient decreaseswith increasing SF6content at a given reduced field strength.(2) The electron swarm data and effective ionization coefficient are calculated byintroducing inert gases. Moreover，streamer breakdown mechanism is introduced topredict the breakdown voltage in the ozonizers. Results show that inert gas additionswould lead to increasing effective ionization coefficient and decreasing breakdownvoltage.(3) Assisted by Boltzmann analysis, the influence of inert gases on ozoneconcentration, ozone conversion and ozone yield are analyzed. Results show that dueto the excited threshold value of inert gas species and the reaction coefficient,Penning disassociation of excited species and oxygen therefore contribute aconsiderable role in ozone formation. |
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