Fog collection with hairy wires

Abstract

Fog collection can be an affordable, practical solution to water scarcity in many regions around the world. Commercial fog harvesters typically use mesh structures composed of cylindrical wires or thin strips. The choice of their length scale, especially the width, has been a challenge due to a trade-off problem—wide wires or strips cause fog droplets to avoid contact and display lower deposition efficiency, while meshes comprising thin cylinders or strips often suffer from clogging and exhibit low drainage efficiency. In this study, we propose a cost-effective dual-scale structure, a vertical core composed of two twisted cylindrical wires surrounded by thin hairs protruding along radial direction, which can greatly improve the water collection efficiency by decoupling the mechanisms for droplet deposition and drain: while thin hairs allow fog droplets to retain high Stokes number and deposit with high efficiency, a vertical core functions as a wicking mechanism for deposited droplets to drain quickly. Fabricated hairy wires have a water collection rate of more than two and a half times that of smooth cylindrical wires of the same diameter, and their steady-state performance does not suffer from clogging, in contrast to conventional meshes composed of thin wires. Proposed hairy wires can be mass-produced by slightly modifying commercial products. This study provides a practical solution for the optimal design of fog collectors, benefiting the fight against the global water crisis.

References

[1] Rijsberman FR. Water scarcity: fact or fiction? Agric Water Manage. 2006; 80: 5-22.

[2] Boretti A, Rosa L. Reassessing the projections of the world water development report. NPJ Clean Water. 2019; 2: 15.

[3] Klemm O, Schemenauer RS, Lummerich A, et al. Fog as a fresh-water resource: overview and perspectives. Ambio. 2012; 41: 221-234.

[4] Domen JK, Stringfellow WT, Camarillo MK, Gulati S. Fog water as an alternative and sustainable water resource. Clean Technol Environ Policy. 2014; 16: 235-249.

[5] Jiang Y, Machado C, Park KCK. From capture to transport: a review of engineered surfaces for fog collection. Droplet. 2023; 2:e55.

[6] Kennedy BS, Boreyko JB. Bio-inspired fog harvesting meshes: a review. Adv Funct Mater. 2024; 34:2306162.

[7] Macedonio F, Drioli E, Gusev AA, Bardow A, Semiat R, Kurihara M. Efficient technologies for worldwide clean water supply. Chem Eng Process. 2012; 51: 2-17.

[8] Ghaffour N, Missimer TM, Amy GL. Technical review and evaluation of the economics of water desalination: current and future challenges for better water supply sustainability. Desalination. 2013; 309: 197-207.

[9] Gupta VK, Ali I, Saleh TA, Nayak A, Agarwal S. Chemical treatment technologies for waste-water recycling-an overview. RSC Adv. 2012; 2: 6380-6388.

[10] Salgot M, Folch M. Wastewater treatment and water reuse. CurrOpin Environ Sci Health. 2018; 2: 64-74.

[11] Gultepe I, Tardif R, Michaelides SC, et al. Fog research: a review of past achievements and future perspectives. Pure Appl Geophys. 2007; 164: 1121-1159.

[12] Azeem M, Noman MT, Wiener J, Petru M, Louda P. Structural design of efficient fog collectors: a review. Environ Technol Innovation. 2020; 20:101169.

[13] Verbrugghe N, Khan AZ. Water harvesting through fog collectors: a review of conceptual, experimental and operational aspects. Int J Low Carbon Technol. 2023; 18: 392-403.

[14] Brunazzi E, Paglianti A. Design of complex wire-mesh mist eliminators. AIChE J. 2000; 46: 1131-1137.

[15] El-Dessouky HT, Alatiqi IM, Ettouney HM, Al-Deffeeri NS. Performance of wire mesh mist eliminator. Chem Eng Process. 2000; 39: 129-139.

[16] Jiang Y, Savarirayan S, Yao Y, Park KC. Fog collection on a superhydrophilic wire. Appl Phys Lett. 2019; 114:083701.

[17] Dios Rivera dJ. Aerodynamic collection efficiency of fog water collectors. Atmos Res. 2011; 102: 335-342.

[18] Park KC, Chhatre SS, Srinivasan S, Cohen RE, McKinley GH. Optimal design of permeable fiber network structures for fog harvesting. Langmuir. 2013; 29: 13269-13277.

[19] Schunk C, Trautwein P, Hruschka H, et al. Testing water yield, efficiency of different meshes and water quality with a novel fog collector for high wind speeds. Aerosol Air Quality Res. 2018; 18: 240-253.

[20] Regalado CM, Ritter A. The design of an optimal fog water collector: A theoretical analysis. Atmos Res. 2016; 178: 45-54.

[21] Li J, Ran R, Wang H, et al. Aerodynamics-assisted, efficient and scalable kirigami fog collectors. Nat Commun. 2021; 12: 5484.

[22] Moncuquet A, Mitranescu A, Marchand OC, Ramananarivo S, Duprat C. Collecting fog with vertical fibres: combined laboratory and in-situ study. Atmos Res. 2022; 277:106312.

[23] Mukhopadhyay A, Datta A, Dutta PS, Datta A, Ganguly R. Droplet morphology-based wettability tuning and design of fog harvesting mesh to minimize mesh-clogging. Langmuir. 2024; 40: 8094-8107.

[24] Park J, Lee C, Lee S, Cho H, Moon MW, Kim SJ. Clogged water bridges for fog harvesting. Soft Matter. 2021; 17: 136-144.

[25] Shi W, Anderson MJ, Tulkoff JB, Kennedy BS, Boreyko JB. Fog harvesting with harps. ACS Appl Mater Interfaces. 2018; 10: 11979-11986.

[26] Shi W, van der Sloot TW, Hart BJ, Kennedy BS, Boreyko JB. Harps enable water harvesting under light fog conditions. Adv Sustain Syst2020; 4:2000040.

[27] Kowalski NG, Shi W, Kennedy BS, Boreyko JB. Optimizing fog harps. ACS Appl Mater Interfaces. 2021; 13: 38826-38834.

[28] Kowalski NG, Boreyko JB. Dynamics of fog droplets on a harp wire. Soft Matter. 2022; 18: 7148-7158.

[29] Kaindu JK, Murphy KR, Kowalski NG, et al. Antitangling and manufacturable fog harps for high-efficiency water harvesting. Droplet. 2023; 2:e78.

[30] Bai H, Zhao T, Wang X, et al. Cactus kirigami for efficient fog harvesting: simplifying a 3D cactus into 2D paper art. J Mater Chem A. 2020; 8: 13452-13458.

[31] Ju J, Bai H, Zheng Y, Zhao T, Fang R, Jiang L. A multi-structural and multi-functional integrated fog collection system in cactus. Nat Commun. 2012; 3: 1247.

[32] Kanooni A, Kohan MR. Fog water harvesting with cylindrical brush. Sci Rep. 2024; 14:19679.

[33] Langmuir I, Blodgett K. A mathematical investigation of water droplet trajectories. No. 5418Army Air Forces Headquarters, Air Technical Service Command; 1946.

[34] Princen H. Capillary phenomena in assemblies of parallel cylinders: II. Capillary rise in systems with more than two cylinders. J Colloid Interface Sci. 1969; 30: 359-371.

[35] Py C, Reverdy P, Doppler L, Bico J, Roman B, Baroud CN. Capillary origami: spontaneous wrapping of a droplet with an elastic sheet. Phys Rev Lett. 2007; 98:156103.

[36] Pokroy B, Kang SH, Mahadevan L, Aizenberg J. Self-organization of a mesoscale bristle into ordered, hierarchical helical assemblies. Science. 2009; 323: 237-240.

[37] Jiang Y, Machado C, Savarirayan S, Patankar NA, Park KC. Onset time of fog collection. Soft Matter. 2019; 15: 6779-6783.

[38] Boreyko JB, Chen CH. Self-propelled dropwise condensate on superhydrophobic surfaces. Phys Rev Lett. 2009; 103:184501.

[39] Jiang Y, Feng L, O'Donnell A, et al. Coalescence-induced propulsion of droplets on a superhydrophilic wire. Appl Phys Lett. 2022; 121:231602.

[40] Feng L, Jiang Y, Machado C, Choi W, Patankar NA, Park KC. Short-time asymmetric droplet coalescence dynamics on a pre-wetted fiber. Appl Phys Lett. 2024; 125:061601.

RIGHTS & PERMISSIONS

2025 The Author(s). Droplet published by Jilin University and John Wiley & Sons Australia, Ltd.