In flame spray pyrolysis (FSP), the evolution of metal oxide nanoparticles relies on quite a number of droplet (liquid) and vapor phase related physical mechanism as for instance precursor evaporation, oxidation, nucleation via gas‐to‐particle conversion mechanism, and subsequent particle (solid) growth mechanisms based on coagulation, sintering/coalescence, and agglomeration. The liquid precursor and dispersion oxygen feed rates are relevant control parameters of the FSP process for tailoring the nanoparticle size (diameter) and structure as well as the atomizer nozzle configuration. Sophisticated nonintrusive, laser‐based in situ and ex situ diagnostics with multiscale spatial resolution (micrometer to meter range) are applied for analyzing droplet formation and size, gas velocity, temperature, species concentration, as well as primary and agglomerate diameters along the flow direction. Computational fluid dynamics (CFD) are coupled with population balance modeling (PBM) to elucidate the nanoparticle dynamics within the reactive spray. It is found that the CFD‐PBM approach allows estimations of primary and agglomerate nanoparticle diameters within 80 and 75% accuracy compared to experimental data, suggesting that the methods presented could pave the way for designing next‐generations of flame reactors.

中文翻译：

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火焰喷雾热解中的纳米颗粒演化—通过实验和计算分析进行工艺设计

在火焰喷雾热解（FSP）中，金属氧化物纳米颗粒的演化依赖于许多与液滴（液相）和气相相关的物理机制，例如前体蒸发，氧化，通过气-粒转化机制的成核以及随后的过程。基于凝聚，烧结/聚结和团聚的颗粒（固体）生长机制。液态前驱物和分散体氧气的进料速度是FSP工艺的相关控制参数，用于调整纳米粒子的尺寸（直径）和结构以及雾化器喷嘴的配置。具有多尺度空间分辨率（微米至米范围）的先进的基于激光的非侵入式原位和非原位诊断技术可用于分析液滴的形成和大小，气体速度，温度，物质浓度，以及沿流动方向的主直径和附聚物直径。计算流体动力学（CFD）与总体平衡模型（PBM）结合以阐明反应性喷雾中的纳米颗粒动力学。结果发现，与实验数据相比，CFD-PBM方法可以估算初级和团聚纳米颗粒直径，准确度在80％和75％之内，这表明所提出的方法可以为设计下一代火焰反应堆铺平道路。