Collaborative Research: Template-Free Manufacturing of Regular Microstructures by Ribbing-Enhanced Roll Coating

合作研究：通过罗纹增强辊涂无模板制造规则微结构

• 批准号: 2030404
• 负责人: Chang-Jin Kim
• 金额: $ 44.95万
• 依托单位: University of California-Los Angeles
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-01 至 2025-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2030404&HistoricalAwards=false
• 关键词: Collaborative; Research; Template; Free; Manufacturing

A technology that can reduce the friction or drag on ship hulls would have a substantial economic and environmental impact by improving fuel efficiency. Microstructured superhydrophobic surfaces may retain air pockets that can act as gas lubrication between the water and the ship hull. Although the superhydrophobic surfaces have been studied for nearly two decades, it is only recently that periodic linear-trench structures have been shown to be effective for marine crafts traveling in open water, which represents sea, oceans, and lakes. The manufacturing of such well-defined micro-trenches has relied on silicon-based microfabrication based on semiconductor manufacturing approaches. These silicon processes are prohibitively expensive and not scalable for large surface areas, such as ship hulls. To address these challenges, a team from North Carolina State University and University of California at Los Angeles would like to utilize roll coating methodology, which is well known for cost-effective and large-scale production, to form the periodic microstructures on large substrates. This new process is researched to develop friction-reduction coatings for ship hulls and study their physical and chemical durability. Hence, outcomes from this research will benefit a wide array of marine applications, including commercial and military ships, which play a significant role in the national and global economies and security applications. This project is investigates the spontaneous pattern generation by ribbing on polymer surfaces during roll coating in an ordered manner using a fundamentally new approach to manufacture three-dimensional micro and nano-scale structures on a large-area substrate. The objectives are to establish the scientific foundation to control the microstructures formed during the roll coating, and to fabricate and validate the drag reduction efficiency of the surfaces in realistic flow conditions of open water and Reynolds number greater than 1 million. The research team will utilize computational modeling to predict the deformation behavior of the viscoelastic polymer verified by the experimental observations. For the proof-of-concept of drag reduction in realistic flows, a microstructured film and a smooth film will be layered on the bottom of a motorboat specifically outfitted to reliably compare the fluid shear stresses on the two. This project will educate the next generation of engineers and scientists through multidisciplinary research involving manufacturing, materials science, computational modeling, and fluid mechanics. The research outcome will be also used to educate K-12, undergraduate, as well as graduate-level students through various formats such as outreach activities and innovative curricular efforts.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

一项可以减少船体摩擦或阻力的技术将通过提高燃油效率对经济和环境产生重大影响。微观结构的超疏水表面可能保留气穴，可以作为水和船体之间的气体润滑。虽然超疏水表面已经研究了近二十年，但直到最近，周期性线性沟槽结构才被证明对在开阔水域（代表海洋、海洋和湖泊）航行的船舶有效。这种定义明确的微沟槽的制造依赖于基于半导体制造方法的硅基微加工。这些硅工艺非常昂贵，而且不能扩展到像船体这样的大表面区域。为了应对这些挑战，来自北卡罗莱纳州立大学和加州大学洛杉矶分校的一个团队希望利用以成本效益和大规模生产而闻名的滚动涂层方法，在大型基材上形成周期性微结构。研究了船体减摩擦涂层的新工艺，并对其物理和化学耐久性进行了研究。因此，这项研究的成果将有利于广泛的海洋应用，包括商业和军用船舶，在国家和全球经济和安全应用中发挥重要作用。该项目研究了聚合物表面在滚涂过程中以有序方式产生的自发图案，采用了一种全新的方法在大面积基板上制造三维微纳米尺度结构。目的是为控制滚涂过程中形成的微观组织奠定科学基础，并在开放水域和雷诺数大于100万的实际流动条件下制造和验证表面的减阻效率。研究小组将利用计算模型来预测粘弹性聚合物的变形行为，并通过实验观察进行验证。为了验证在实际流动中减少阻力的概念，一层微结构膜和一层光滑膜将被分层放置在一艘摩托艇的底部，以可靠地比较两者的流体剪切应力。该项目将通过涉及制造、材料科学、计算建模和流体力学的多学科研究，培养下一代工程师和科学家。研究成果还将通过各种形式，如外展活动和创新课程，用于教育K-12，本科和研究生水平的学生。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Sustainability of the plastron on nano-grass-covered micro-trench superhydrophobic surfaces in high-speed flows of open water

• DOI: 10.1017/jfm.2023.184
• 发表时间: 2023-04
• 期刊: Journal of Fluid Mechanics
• 影响因子: 3.7
• 作者: Ning Yu;Z. R. Li;Alexander McClelland;Francisco Jose del Campo Melchor;Sun Youb Lee;Jae Hwa Lee;C. Kim

Combined Theory and Experimental Verification of Plastron Stability on Superhydrophobic Surface

超疏水表面腹甲稳定性的理论与实验相结合的验证

• DOI: 10.1109/mems51670.2022.9699456
• 发表时间: 2022
• 期刊: IEEE 35th International Conference on Micro Electro Mechanical Systems Conference (MEMS
• 作者: Yu, Ning;Li, Zhaohui Ray;McClelland, Alexander;Kim, Chang-Jin CJ
• 通讯作者: Kim, Chang-Jin CJ

Superhydrophobic drag reduction in turbulent flows: a critical review

• DOI: 10.1007/s00348-021-03322-4
• 发表时间: 2021-10
• 期刊: Experiments in Fluids
• 影响因子: 2.4
• 作者: Hyungmin Park;Chang‐Hwan Choi;C. Kim

Template‐Free Scalable Fabrication of Linearly Periodic Microstructures by Controlling Ribbing Defects Phenomenon in Forward Roll Coating for Multifunctional Applications

• DOI: 10.1002/admi.202201237
• 发表时间: 2022-08
• 期刊: Advanced Materials Interfaces
• 影响因子: 5.4
• 作者: Md. Didarul Islam;Himendra Perera;B. Black;Matthew Phillips;Muh-Jang Chen;G. Hodges;Allyce Jackman;Yuxuan Liu;C. Kim;M. Zikry;Saad A Khan;Yong Zhu;M. Pankow;J. Ryu