Reduction of skin-friction in large-scale turbulent flows using superhydrophobic surfaces

使用超疏水表面减少大规模湍流中的表面摩擦

• 批准号: RGPIN-2014-04320
• 负责人: Ghaemi, Sina
• 金额: $ 1.68万
• 依托单位: University of Alberta
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=679393
• 关键词: Reduction; skin; friction; large; scale

Skin-friction force opposes the motion of a fluid over a solid surface. It forms almost all the opposing force in transportation of oil and gas through pipelines and also a substantial portion of the drag force acting on aircraft and marine vehicles. The ubiquitous resistance of skin-friction in the transportation industry and its direct impact on the annual fuel consumption and emission of pollutants have promoted research on different mitigation methods.*Advances in micro/nano fabrication have introduced synthetic superhydrophobic surface as a method with significant potential for reduction of skin-friction in liquid flows. A superhydrophobic surface is formed by micro/nanoscale roughness covered by a thin hydrophobic coating which prevents liquid from entering the cavities. This combination results in formation of liquid-air interface with negligible friction allowing the liquid to freely slip. The performance of superhydrophobic surfaces in turbulent flows has been observed to be different than the laminar regime indicating a complex mechanism depending on the flow regime.*The objective of the proposed research program is to investigate the application of superhydrophobic surfaces for reduction of skin-friction in large-scale turbulent flows relevant to industrial applications. The research will include a detailed characterization of the turbulent boundary layer at the immediate vicinity of the surface in order to identify the mechanism of skin-friction reduction. Development of models and superhydrophobic surfaces with maximum reduction of skin-friction and longevity of the air-liquid interface will be pursued.*The proposed research will provide the practical guidelines for long-term goal of reduction of skin-friction and consequently development of efficient and environmentally friendly pipelines of oil, petroleum products, and carbon dioxide across Canada.

表面摩擦力与流体在固体表面上的运动相反。 它形成了通过管道运输石油和天然气的几乎所有阻力，也是作用在飞机和海上车辆上的阻力的很大一部分。 在交通运输行业中，表面摩擦阻力无处不在，它对年燃料消耗和污染物排放的直接影响促进了对不同缓解方法的研究。微/纳米制造技术的发展引入了合成超疏水表面作为一种具有显著潜力的方法，用于减少液体流动中的表面摩擦。 超疏水表面由微/纳米级粗糙度形成，粗糙度被薄疏水涂层覆盖，该涂层防止液体进入腔体。 这种组合导致形成具有可忽略摩擦的液体-空气界面，从而允许液体自由滑动。 已经观察到超疏水表面在湍流中的性能不同于层流状态，表明取决于流状态的复杂机制。拟议的研究计划的目的是研究超疏水表面的应用，以减少与工业应用相关的大规模湍流中的表面摩擦。 这项研究将包括对表面附近紊流边界层的详细描述，以确定减少表面摩擦的机制。 将致力于开发最大限度地减少表面摩擦和延长气液界面寿命的模型和超疏水表面。拟议的研究将为减少皮肤摩擦的长期目标提供实用的指导方针，从而在加拿大各地开发高效和环保的石油，石油产品和二氧化碳管道。