Numerical Analysis of the Formation of TiO2 Nanoparticles in Gas Phase Explosion Flow Field
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摘要: 气相爆炸制备TiO2纳米颗粒的实验成果在近年来多有报道,但对颗粒成长的模拟尚不多见。引入一种气溶胶的单分散性物理模型(Kruis模型),将其应用于气相爆炸流场中TiO2纳米颗粒生长的数值模拟,结合气相爆炸制备实验进行对比分析。结果表明,通过控制前驱体反应组分,气相爆轰合成了直径范围为20~150 nm的球形TiO2纳米颗粒。数值模拟得到的颗粒大小与实验观测结果基本一致。影响纳米颗粒生长的主要因素包括反应温度、颗粒浓度及反应时间。
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关键词:
- 气相爆炸 /
- 二氧化钛(TiO2) /
- 纳米颗粒成长 /
- 数值分析
Abstract: A monodisperse model was introduced to simulate the TiO2 nanoparticles synthesization during the gas phase explosion.The calculation of this model was based on the experimental results and CJ theory which describes the gas phase explosion field.After a numerical analysis and theoretical explanation, the model was validated in comparison with the experimental results of gas phase explosion synthesis of TiO2.TiO2 nanoparticles with diameter of 20-150 nm were obtained.The results show that the numerical analysis can give a rapid predictive result of TiO2 nanoparticles synthesis, and the main factors affecting the growth of nanoparticles are reaction temperature, concentration of particles and reaction time. -
表 1 气相爆炸实验条件及TiO2纳米颗粒特征
Table 1. Experimental conditions and TiO2 characteristics by gas-phase detonation
Sample
No.TiCl4:H2:O2
(Volume ratio)Mass fraction of components/(%) Particle diameter/(nm) Anatase Rutile Anatase Rutile 1 1.0:3.0:1.0 11.2 88.8 22.12 41.94 2 1.0:2.5:1.0 28.1 71.9 19.64 37.61 3 1.0:2.0:1.0 45.0 55.0 26.24 37.70 Note:The particle diameters are calculated by Scherrer equation. -
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