Scalable and Resilient Etched Metallic Micro- and Nanostructured Surfaces for Enhanced Flow Boiling
Scalable and Resilient Etched Metallic Micro- and Nanostructured Surfaces for Enhanced Flow Boiling
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DOI：
10.1021/acsanm.1c00524
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发表时间：
2021-07
影响因子：
5.9
通讯作者：
N. Upot;Allison Mahvi;Kazi Fazle Rabbi;Jiaqi Li;A. Jacobi;N. Miljkovic
中科院分区：
文献类型：
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作者：
N. Upot;Allison Mahvi;Kazi Fazle Rabbi;Jiaqi Li;A. Jacobi;N. Miljkovic
管道和通道中的流动沸腾和蒸发发生在各种能源系统中，例如制冷、空调、发电、电子冷却、蒸馏和净化。在这项工作中，我们证明，与光滑的非结构化铝管相比，在可扩展微结构（~40 μm）、工业规模（~1 m 长）铝 (Al) 管中制冷剂流动沸腾期间，传热系数显着提高了 270%。为了实现可扩展的纳米制造，我们依靠盐酸铝蚀刻来创建高度共形且耐用的结构化表面。使用 R134a 制冷剂作为工作流体，在直径 6.35 mm 的铝管中进行流动沸腾测试。为了对我们的方法进行基准测试并阐明结构长度尺度的影响，我们还制造了超可扩展的勃姆石（AlO（OH））纳米结构（~300 nm）铝管，表明蚀刻的微米级特征是增强的必要性和关键。使用 28 天的连续流动沸腾实验进行的耐久性测试表明，蚀刻表面的降解可以忽略不计。与当前的增强方法（例如挤压、拉拔和焊接）相比，用于创建这些耐用的蚀刻铝微结构的可扩展且经济有效的技术可以显着降低制造成本。
Flow boiling and evaporation in tubes and channels occur in a wide variety of energy systems, such as refrigeration, air conditioning, power generation, electronics cooling, distillation, and purification. In this work, we demonstrate remarkably increased heat transfer coefficients of 270% during refrigerant flow boiling in scalable microstructured (∼40 μm), industrial-scale (∼1 m long) aluminum (Al) tubes, when compared to smooth unstructured Al tubes. To achieve scalable nanomanufacturing, we create highly conformal and durable structured surfaces by relying on hydrochloric acid Al etching. Flow boiling tests were conducted in 6.35 mm diameter Al tubes using R134a refrigerant as the working fluid. To benchmark our approach and to elucidate the effect of the structure length scale, we also fabricated ultrascalable boehmite (AlO(OH)) nanostructured (∼300 nm) Al tubes, showing that etched microscale features are necessary and key to enhancement. Durability tests conducted using a 28 day long continual flow boiling experiment demonstrated negligible degradation of the etched surfaces. The scalable and cost-effective techniques used to create these durable, etched-Al microstructures may significantly reduce manufacturing cost when contrasted with current enhancement approaches such as extrusion, drawing, and welding.