EAGER: Experimental Study of Condensation Enhancement on Durable Slippery Surfaces

EAGER：耐用光滑表面上凝结增强的实验研究

• 批准号: 1929677
• 负责人: Xianming Dai
• 金额: $ 17万
• 依托单位: University of Texas at Dallas
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-06-01 至 2022-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1929677&HistoricalAwards=false
• 关键词: EAGER; Experimental; Study; Condensation; Enhancement

Enhancing condensation improves power plant efficiency, water harvesting, desalination, and refrigeration. An ideal surface for condensation enhancement must provide large heat transfer areas and rapid droplet removal in durable operations. Until now, this could not be achieved because of scientific challenges in both droplet removal and surface durability. First, the passive liquid repellency on air-independent rough surfaces has not been achieved due to the large pinning forces on rough surfaces. Second, the surface durability in a steam environment with continuous droplet shedding cannot be sustained. Most of existing liquid-repellent surfaces rely on the existence of air lubricant, which can be displaced in a steam environment or in contact with low surface tension fluids, leading to the failure of condensate removal. The goal of this EAGER project is to address those challenges by developing previously unachieved hydrophilic and slippery rough surfaces. The research outcomes are integrated with outreach and education, with under-represented students recruited and trained. The PI also actively approaches the industrial companies in Texas for broad impact of the research .The experimental study of condensation enhancement on air-independent slippery rough surfaces leads to a conceptually different strategy from the air-dependent condensation on superhydrophobic surfaces. This hydrophilic slippery rough surface gives a large surface area for condensation and in the meantime keeps a small contact angle hysteresis for condensate removal. The research objectives include: (1) experimentally demonstrate that the slippery rough surfaces can significantly increase the condensation heat transfer coefficient compared with the state-of-the-art condensing surfaces, and (2) understand the failure mechanism of this surface in a steam environment with continuous droplet shedding. To improve surface durability, polymer chains are grafted on the rough substrate to simultaneously enhance heat transfer areas and droplet removal. This project leads to the development of durable air-independent slippery rough surfaces for exceptional condensation enhancement.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.

加强冷凝可以提高发电厂的效率、水收集、脱盐和制冷。理想的冷凝强化表面必须提供大的传热面积和持久运行中的快速液滴去除。到目前为止，由于在液滴去除和表面耐久性方面的科学挑战，这还无法实现。首先，由于粗糙表面上的大的钉扎力，在不依赖于空气的粗糙表面上的被动液体排斥性尚未实现。第二，在具有连续液滴脱落的蒸汽环境中的表面耐久性不能持续。大多数现有的液体排斥表面依赖于空气润滑剂的存在，其可以在蒸汽环境中或与低表面张力流体接触时被置换，导致冷凝物去除失败。EAGER项目的目标是通过开发以前未实现的亲水和光滑粗糙表面来解决这些挑战。研究成果与外联和教育相结合，招募和培训了代表性不足的学生。PI还积极接触德克萨斯州的工业公司，以获得研究的广泛影响。在不依赖于空气的光滑粗糙表面上进行的冷凝增强实验研究导致了与超疏水表面上依赖于空气的冷凝在概念上不同的策略。这种亲水光滑的粗糙表面为冷凝提供了大的表面积，同时为冷凝物的去除保持了小的接触角滞后。研究目标包括：（1）实验证明光滑粗糙表面与现有技术的冷凝表面相比可以显著地增加冷凝传热系数，以及（2）理解这种表面在具有连续液滴脱落的蒸汽环境中的失效机理。为了提高表面耐久性，将聚合物链接枝在粗糙基材上，以同时增强传热面积和液滴去除。该项目导致了持久的空气独立光滑粗糙表面的发展，以实现卓越的冷凝增强。该奖项反映了NSF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

Gradient Quasi‐Liquid Surface Enabled Self‐Propulsion of Highly Wetting Liquids

• DOI: 10.1002/adfm.202008614
• 发表时间: 2021-01
• 期刊: Advanced Functional Materials
• 影响因子: 19
• 作者: Lei Zhang;Zongqi Guo;Jyotirmoyee Sarma;Weiwei Zhao;X. Dai

Molecular Dynamics Simulations of Water Condensation on Surfaces with Tunable Wettability

• DOI: 10.1021/acs.langmuir.0c00915
• 发表时间: 2020-07-07
• 期刊: LANGMUIR
• 影响因子: 3.9
• 作者: Ranathunga, Dineli T. S.;Shamir, Alexandra;Nielsen, Steven O.
• 通讯作者: Nielsen, Steven O.

Hydrophilic slippery surface enabled coarsening effect for rapid water harvesting

• DOI: 10.1016/j.xcrp.2021.100387
• 发表时间: 2021-04-21
• 期刊: CELL REPORTS PHYSICAL SCIENCE
• 影响因子: 8.9
• 作者: Guo, Zongqi;Zhang, Lei;Dai, Xianming
• 通讯作者: Dai, Xianming

Designing air-independent slippery rough surfaces for condensation

• DOI: 10.1016/j.ijheatmasstransfer.2019.06.035
• 发表时间: 2019-09
• 期刊: International Journal of Heat and Mass Transfer
• 影响因子: 5.2
• 作者: G. Sirohia;X. Dai