由于带有颗粒的流动而导致的侵蚀和沉积的调查
Sol Johanne Mehammer1, Martin M Greve1, Pawel Kosinski1
1Department of Physics and Technology, University of Bergen, Postbox 7803, Bergen 5020, Norway.
Langmuir : the ACS journal of surfaces and colloids
|November 14, 2024
概括
微/中等尺度的沙粒会导致侵蚀,而纳米尺度的氧化铁颗粒会导致多相流中的沉积和腐蚀. 这项研究调查了具有增强热性质的流体中的粒子行为.
科学领域:
- 多相流动动力学 多相流动力学
- 材料科学与工程 材料科学与工程
- 纳米技术的应用.
背景情况:
- 纳米流体提供了增强的热性能,但由于侵蚀和沉积,在工程应用中面临挑战.
- 了解粒子-流体相互作用对于纳米流体的实际实施至关重要.
研究的目的:
- 为了研究颗粒侵蚀和沉积,在多相流中含有微/介质和纳米级颗粒.
- 在流量条件下分析沙子和氧化铁纳米颗粒对表面的影响.
主要方法:
- 实验研究涉及将板长时间浸入旋转的带颗粒液体中的实验研究.
- 使用扫描电子显微镜 (SEM),原子力显微镜 (AFM) 和能量分散X射线 (EDX) 分析进行表面分析.
- 理论分析包括动量响应时间和特征流量时间比较,以及计算流体动力学 (CFD) 模拟.
主要成果:
- 识别出微/中等尺度的沙粒是侵蚀的主要原因.
- 纳米铁氧化物颗粒导致了显著的沉积和腐蚀,形成氧化,而不是明显的侵蚀.
- 理论和CFD分析证实了关于粒子行为的实验观测.
结论:
- 不同的颗粒大小在多相流中表现出不同的行为 (侵蚀与沉积/腐蚀).
- 纳米颗粒沉积和随后的腐蚀对纳米流体在工程系统中的应用提出了重大挑战.
- 需要进一步的研究,以减轻实际纳米流体利用的沉积和腐蚀问题.
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