论文标题
泰勒气泡流的热量增强使用铁洛泳
On-demand augmentation in heat transfer of Taylor bubble flows using ferrofluids
论文作者
论文摘要
磁场的应用可能会影响铁漏的热流体传输特性。从最近的研究中可以明显看出，铁洛泳的磁操作对于增强传热很有用。在本研究中，我们研究了一种增强两相传热的新策略，并表明非沸腾的泰勒气泡流（TBF）的磁性操纵可以提供按需增强。在较早的研究（doi：10.1016/j.colsurfa.2020.124589）中，我们表明，铁氟烷TBF的特征可以通过外部磁性操纵来改变。由于TBF的运输特征主要取决于其流动形态，因此预计这种变化会影响其热运输特征，这在本工作中进行了研究。通过磁性操纵的较小气泡和单位电池的产生减少了所得TBF的空隙部分。此外，与较大的气泡刺系统相比，在任何时间实例中，有更多的单位参与热交换过程。这种流动的修饰会导致两相热传递的大量增强（可以高达100％）。增强的程度取决于施加的磁场和诱导的磁力，均匀的气体分数，液体膜厚度/空隙分数和所得TBF的流动形态，这在本研究中进行了检查。 Ferrofluids在TBF中的应用提供了多种好处，例如具有更好的热性能的纳米颗粒的悬架以及通过外部均值进行流动操作的其他功能。建议使用建议的操纵技术的应用为在低雷诺数流中的两相热传递中按需增强提供了有效的替代方法。
The thermo-fluidic transport characteristics of ferrofluids can be influenced by the application of a magnetic field. The magnetic manipulations of ferrofluids have been useful in augmenting heat transfer, as evident from recent investigations. In the present study, we examine a novel strategy for augmenting two-phase heat transfer and show that the magnetic manipulation of non-boiling Taylor bubble flow (TBF) of ferrofluids can provide on-demand augmentation. In an earlier investigation (DOI:10.1016/j.colsurfa.2020.124589), we had shown that the characteristics of the TBF of ferrofluids could be altered through external magnetic manipulations. As transport characteristics of TBFs primarily depend on their flow morphology, it was anticipated that such alteration would affect their thermal transport characteristics, which are examined in the present work. The generation of smaller bubbles and unit-cells through magnetic manipulations decreases the void fraction of the resulting TBF. In addition, a greater number of units participated in the heat exchange process compared to larger bubble-slug systems at any time instance. Such flow modifications cause considerable augmentation (which can go up to 100%) in two-phase heat transfer. The extent of augmentation depends on the applied magnetic field and induced magnetic force, homogeneous gas fraction, liquid film thickness/void fraction and flow morphology of the resulting TBF, which are examined in the present study. The application of ferrofluids in TBFs provides multiple benefits, such as suspension of nanoparticles with better thermal properties and additional functionality of the flow manipulations through external means. The proposed application with the suggested manipulation technique provides an effective alternative for an on-demand augmentation in two-phase heat transfer in low Reynolds number flows.
