TY - JOUR
T1 - Experimental investigations of liquid-infused surface robustness under turbulent flow
AU - Fu, Matthew K.
AU - Chen, Ting Hsuan
AU - Arnold, Craig B.
AU - Hultmark, Marcus Nils
N1 - Funding Information:
This work was supported under the Office of Naval Research (ONR) Multidisciplinary University Research Initiative (MURI) Grants N00014-12-0875 and N00014-12-1-0962, Program Manager Dr. Ki-Han Kim. M. K. Fu was also supported, in part, by the Department of Defense (DoD) through the National Defense Science and Engineering Graduate Fellowship (NDSEG) Program.
Funding Information:
The authors are thankful to all of the former and current members of the ONR MURI SLIPS team, especially Ying Liu, Dr. Rémy Mensire, Dr. Jason Wexler, Prof. Ian Jacobi, Dr. Brian Rosenberg, Prof. Howard Stone and Prof. Alexander Smits for their insight and discussions. The authors would also like to thank Dr. Tyler Van Buren and Dan Hoffman for their assistance in manufacturing the aluminum substrates. The authors would also like to thank Karen Wang, Kevin Lee, and Raj Balaji for their assistance in designing, manufacturing, and characterizing the channel facility.
Publisher Copyright:
© 2019, Springer-Verlag GmbH Germany, part of Springer Nature.
PY - 2019/6/1
Y1 - 2019/6/1
N2 - Liquid-infused surfaces present a novel coating for passive drag reduction in turbulent flows. Conceptually similar to superhydrophobic surfaces, which are composed of air pockets trapped within hydrophobic roughness, liquid-infused surfaces instead rely on a preferentially wetting, liquid lubricant to create a heterogeneous surface of fluid–solid and fluid–fluid interfaces. The mobility of the lubricant within the textures allows the fluid–fluid interfaces to support a finite interfacial slip velocity. In the proper configuration, the collection of slipping interfaces can result in a significant reduction in skin friction drag. However, sustaining this drag reduction is predicated on maintaining the integrity of the lubricating layer. While liquid-infused surfaces are robust to the most common sources of superhydrophobic surface failure, they exhibit a distinct susceptibility to shear/slip-driven drainage. Here, the robustness and behavior of lubricant-infused streamwise microgrooves are studied, in a turbulent channel flow facility. In the presence of external turbulent shear flow, a finite length of lubricant is found to be retained within the microtextures by a mechanism analogous to capillary rise, consistent with the observations of Wexler et al. (Phys Rev Lett 114(16):168301, 2015b), while the remainder of the lubricant is driven out of the surface. This retention mechanism is exploited to maintain a lubricating layer over a larger surface area by using a novel chemical patterning technique. Chemical barriers are scribed along the streamwise length of the grooves. These periodic barriers disrupt the continuity of the streamwise groove and inhibit the downstream drainage of the lubricant. The effectiveness of this approach is evaluated in a turbulent channel flow with promising results.
AB - Liquid-infused surfaces present a novel coating for passive drag reduction in turbulent flows. Conceptually similar to superhydrophobic surfaces, which are composed of air pockets trapped within hydrophobic roughness, liquid-infused surfaces instead rely on a preferentially wetting, liquid lubricant to create a heterogeneous surface of fluid–solid and fluid–fluid interfaces. The mobility of the lubricant within the textures allows the fluid–fluid interfaces to support a finite interfacial slip velocity. In the proper configuration, the collection of slipping interfaces can result in a significant reduction in skin friction drag. However, sustaining this drag reduction is predicated on maintaining the integrity of the lubricating layer. While liquid-infused surfaces are robust to the most common sources of superhydrophobic surface failure, they exhibit a distinct susceptibility to shear/slip-driven drainage. Here, the robustness and behavior of lubricant-infused streamwise microgrooves are studied, in a turbulent channel flow facility. In the presence of external turbulent shear flow, a finite length of lubricant is found to be retained within the microtextures by a mechanism analogous to capillary rise, consistent with the observations of Wexler et al. (Phys Rev Lett 114(16):168301, 2015b), while the remainder of the lubricant is driven out of the surface. This retention mechanism is exploited to maintain a lubricating layer over a larger surface area by using a novel chemical patterning technique. Chemical barriers are scribed along the streamwise length of the grooves. These periodic barriers disrupt the continuity of the streamwise groove and inhibit the downstream drainage of the lubricant. The effectiveness of this approach is evaluated in a turbulent channel flow with promising results.
UR - http://www.scopus.com/inward/record.url?scp=85067670340&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85067670340&partnerID=8YFLogxK
U2 - 10.1007/s00348-019-2747-9
DO - 10.1007/s00348-019-2747-9
M3 - Article
AN - SCOPUS:85067670340
SN - 0723-4864
VL - 60
JO - Experiments in Fluids
JF - Experiments in Fluids
IS - 6
M1 - 100
ER -