Impact of co-flow on the spray flame behaviour applied to nanoparticle synthesis
Impact of co-flow on the spray flame behaviour applied to nanoparticle synthesis
复制标题
协流对纳米粒子合成中喷雾火焰行为的影响
DOI：
10.1002/cjce.23386
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发表时间：
2019
期刊：
影响因子：
--
通讯作者：
Dirceu
中科院分区：
文献类型：
--
作者：
Lizoel;Meierhofer;Florian;Bianchi Neto;França Meier;Fritsching;Noriler;Dirceu
火焰喷雾热解（FSP）是合成各种金属和金属氧化物的纳米颗粒的既定工艺。应用FSP反应器的开放或封闭配置是控制反应区中的燃料-氧化剂比的有效工具，从而控制温度分布以及颗粒形成和生长过程。在目前的工作中，几何设置代表一个开放和封闭的火焰反应器进行了比较，并研究其对温度，速度和颗粒特性的影响。此外，几个不同的燃烧反应的动力学机制进行了评估，并分析了它们对局部反应器的温度和气体成分分布的影响。采用欧拉-拉格朗日方法描述多相湍流气液两相流，采用基于粒子数平衡方程（PBE）模型的单分散方法预测颗粒的形成和演化。从开放式反应器的结果，气体进入火焰中的空气夹带质量流率计算。几个数值实验进行了封闭的设置。将适当的共流速率供应到封闭反应器中导致与开放反应器配置所发现的类似的火焰行为。通过减少并流气体，观察到外壳壁上的强再循环区和颗粒沉积。在这种情况下，局部温度显著增加，导致较大的初级纳米颗粒直径。
Flame spray pyrolysis (FSP) is an established process to synthesize nanoparticles of various metals and metal oxides. Applying open or enclosed configurations of the FSP reactor is an efficient tool to control the fuel‐oxidizer ratio in the reaction zone and, thus, the temperature distribution and the particle formation and growth process. In the present work, geometrical setups representing an open and an enclosed flame reactor are compared and their influence on the temperature, velocity, and particle characteristics is investigated. In addition, several distinct kinetic mechanisms for the combustion reactions are evaluated and their effects on the local reactor temperature and gas composition distribution are analyzed. An Eulerian‐Lagrangian approach is adopted to describe the multiphase turbulent gas‐droplet flow and a monodisperse approach based on the population balance equation (PBE) model is implemented to predict the particle formation and evolution. From the open reactor results, the air entrainment mass flow rate of gas into the flame is calculated. Several numerical experiments are performed with the enclosed setup. Supplying an appropriate co‐flow rate into the enclosed reactor results in similar flame behaviour as found for the open reactor configuration. By reducing the co‐flow gas, strong recirculation zones and particle deposition on the enclosure walls are observed. In this situation, the local temperature increases considerably, resulting in larger primary nanoparticle diameters.
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影响因子：
8.4
作者：
Mädler, L;Roessler, A;Weimar, U
通讯作者：
Weimar, U
影响因子：
2.5
作者：
Grossmann, H. K.;Grieb, T.;Maedler, L.
通讯作者：
Maedler, L.
雾化和喷涂参数对纳米粒子生产火焰喷涂工艺的影响
影响因子：
1.2
作者：
D. Noriler;C.D. Rosebrock;L. Mädler;H.F. Meier;U. Fritsching
通讯作者：
U. Fritsching
影响因子：
9.2
作者：
Gockeln, Michael;Pokhrel, Suman;Kun, Robert
通讯作者：
Kun, Robert
影响因子：
3.7
作者：
C. Rosebrock;N. Riefler;T. Wriedt;L. Mädler;S. Tse
通讯作者：
C. Rosebrock;N. Riefler;T. Wriedt;L. Mädler;S. Tse