摘 要：为了更好地模拟火焰 CVD 法合成 TiO₂ 纳米颗粒过程，应 用 CFD 商业软件 Fluent，对火焰气相沉积法合成 TiO2 纳米颗粒的 湍流扩散燃烧过程进行了详细的数值模拟。模拟中，将 TiO₂ 当作一 种准气体，采用非平衡壁面处理及 RNG k- ε湍流模型，考虑 TiCl4/ 空气反应，对 16 种工况的丙烷 / 空气火焰 CVD 法合成纳米 TiO₂颗粒的燃烧过程进行了计算分析。结果表明：模拟的火焰长度与实 验结果符合得较好；空气 / 丙烷比高于恰当比时，火焰温度的模拟 结果与实验结果符合得较好。 

关键词：火焰气相沉积法；纳米颗粒；湍流扩散燃烧；湍流模型

Abstract：To probe into the effects of the interaction of chemistry and fluid mechanics in the process of flame CVD, the simulation of gas velocity and temperature profile in propane/air turbulent diffusion flame for TiO₂ nano-particles production were detailed performed by using the commercial CFD-code Fluent. Taking the reaction of precursor TiCl₄into account, using RNG k - εturbulent model and non-equilibrium wall functions, sixteen runs of gas concentration and temperature profiles in propane/air turbulent diffusion flame for TiO₂ nano-particles production were simulated in details with the pseudo-component titania. The simulation showed that flame length agrees nicely with those visually observed in experiments, and flame temperature agrees nicely when the mole ratio of O₂ /C₃H₈ was high than stoichiometrical ratio. 

Keywords: flame CVD; nano-particles; turbulent diffusion flame; turbulent model