I-Corps: Engineered bio-inspired surface for passive flow control

这个I-Corps项目更广泛的影响/商业潜力源于这样一个事实，即该项目中提出的微纹理表面可以减少阻力-物体在空气或水中移动时所承受的力。地面运输车辆、飞机、无人机、水下船只、风力涡轮机和HVAC风扇都经历阻力的不利影响，包括燃料/电力消耗增加、温室气体排放增加和能源生产减少。使用所提出的技术的潜在效率增益可以为许多行业节省大量的能源成本，减少温室气体排放，并解决与空气动力学/流体动力学效率低下相关的许多问题。例如，由于减阻而导致的5%的效率提高转化为卡车运输业节省50亿美元的燃料，并且转化为风能行业每年额外2000个风力涡轮机的等效能量生产。用于被动流动控制的微纹理表面在提高效率方面提供了独特的机会，因为它可以根据应用设计为最佳性能，以产生尽可能高的效率增益。这个I-Corps项目采用了一种受鲨鱼皮启发的微结构涂层，它被动地改变了物体表面附近的流动，从而减少了空气和水应用中的阻力。在水洞中使用风力涡轮机翼型的部分进行的实验结果表明，由市售聚氨酯制成的所提出的微结构膜可以延迟分离气泡的大小并将其减小60%，分离气泡是导致阻力增加的现象。风洞试验也证实了这种减阻效果。在翼型和圆柱体上分别记录了高达30%和13%的减少。此外，当将微结构涂层施加到表面时，测量到翼型产生的升力增加高达45%。该技术提高燃料和转换效率的能力将对包括地面运输、航空航天和风能在内的许多行业产生变革性影响。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。

The broader impact/commercial potential of this I-Corps project stems from the fact that the micro-textured surface proposed in this project can reduce drag - the force experienced by an object moving through air or water. Ground transportation vehicles, airplanes, drones, underwater vessels, wind turbines, and HVAC fans all experience the adverse effects of drag in terms of increased fuel/electricity consumption, increased greenhouse gas emissions, and reduced energy production. Potential efficiency gains using the proposed technology can save numerous industries significant energy costs, reduce greenhouse gas emissions, and solve a multitude of problems associated with aerodynamic/hydrodynamic inefficiencies. For example, a 5% increase in efficiency due to drag reduction translates to $5 billion in fuel savings for the trucking industry and the equivalent energy production of an additional 2000 wind turbines per year for the wind energy industry. Micro-textured surfaces for passive flow control presents a unique opportunity in enhancing efficiency in that it can be designed for optimal performance depending on the application to yield the highest possible efficiency gains. This I-Corps project features a micro-structured coating inspired by shark-skin, which passively modifies the flow close to the surface of an object resulting in drag reduction both in air and water applications. Experimental results performed using the section of a wind turbine airfoil in a water tunnel showed that the proposed micro-structured film, made out of a commercially available polyurethane, can delay and reduce the size of the separation bubble, the phenomenon responsible for increased drag, by 60%. The effect of this reduction on drag was also confirmed in wind tunnel experiments. Reductions of up to 30% and 13% were recorded over an airfoil and a cylinder, respectively. Additionally, enhancements of up to 45% in lift generated by an airfoil was measured when the micro-structured coating was applied to the surface. The ability of the proposed technology to increase fuel and conversion efficiencies will have a transformative impact in many industries including ground transportation, aerospace, and wind energy.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.