纳米粒子聚合物的流动行为在一个流体化床模拟有孔状结构的基于拖动规律
Shaowei Wang1, Xiaobing Hu1, Niannian Liu2
1Energy and Power Engineering Institute, Henan University of Science and Technology, Luoyang 471003, China.
Nanomaterials (Basel, Switzerland)
|June 26, 2024
概括
这项研究开发了一种新的拖动模型,用于在流体化床中的纳米粒子聚合物. 基于多孔结构的拖动定律准确地预测了流化行为,改善了纳米粒子合成过程.
科学领域:
- 化学工程是化学工程的重要组成部分.
- 流体力学 流体力学 流体力学
- 材料科学 材料科学 材料科学
背景情况:
- 液化床反应堆是有效的纳米粒子合成由于可扩展性和大型气体-固体接触.
- 纳米粒子形成多孔聚合物 (>90%的多孔性),影响流化动态.
- 聚合物多孔性对流化床流动行为的影响仍然不太清楚.
研究的目的:
- 开发和评估一个拖动模型,以解释纳米粒子聚合物的多孔结构.
- 为了研究多孔结构对纳米粒子聚合物在流化床中的水力动力学的影响.
- 评估基于多孔结构的阻力规律对于欧勒-欧勒两流体模型的适用性.
主要方法:
- 开发了一种阻力模型,将基于多孔结构的阻力规律纳入欧利尔-欧利尔的两流体模型.
- 在颗粒物和泡流化方案中进行了数值模拟.
- 对关键流化参数的实验数据进行验证的模型预测.
主要成果:
- 基于多孔结构的阻力定律,特别是对于碎形多孔球,与实验数据的一致性比固体球模型更好.
- 准确预测最小流化速度,泡速度,床膨胀比率和聚合物分散系数.
- 证明了孔隙结构对气体-固体流动行为的显著影响.
结论:
- 孔隙结构显著影响了纳米粒子聚合物在流体化床中的气体-固体流动行为.
- 基于多孔结构的阻力定律更适合于模拟纳米颗粒聚合物流化床.
- 开发的模型增强了纳米粒子合成和处理在流体化床中的理解和预测.
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