Drag reduction for viscous laminar flow on spray-coated non-wetting surfaces
Name
McKinley_Drag reduction.pdf
Size
1.84 MB
Format
Adobe PDF
Checksum (MD5)
9499d5ea950b9b53197580c561219b49
Author(s)
Srinivasan, Siddarth
Choi, Wonjae
Park, Kyoo-Chul
Chhatre, Shreerang S.
Cohen, Robert E.
McKinley, Gareth H.
Park, Kyoo Chul
Date Issued
2013
Journal
Soft Matter
Publisher
Royal Society of Chemistry
Citation
Srinivasan, Siddarth, Wonjae Choi, Kyoo-Chul Park, Shreerang S. Chhatre, Robert E. Cohen, and Gareth H. McKinley. “Drag reduction for viscous laminar flow on spray-coated non-wetting surfaces.” Soft Matter 9, no. 24 (2013): 5691.
Version
Final published version
Abstract
We estimate the effective Navier-slip length for flow over a spray-fabricated liquid-repellent surface which supports a composite solid–air–liquid interface or ‘Cassie–Baxter’ state. The morphology of the coated substrate consists of randomly distributed corpuscular microstructures which encapsulate a film of trapped air (or ‘plastron’) upon contact with liquid. The reduction in viscous skin friction due to the plastron is evaluated using torque measurements in a parallel plate rheometer resulting in a measured slip length of bslip z 39 mm, comparable to the mean periodicity of the microstructure evaluated from confocal fluorescence microscopy. The introduction of a large primary length-scale using dual-textured spray-coated meshes increases the magnitude of the effective slip length to values in the range 94 mm # b[subscript slip] # 213 mm depending on the geometric features of the mesh. The wetted solid fractions on each mesh are calculated from free surface simulations on model sinusoidal mesh geometries. The trend in measured values of b[subscript slip] with the mesh periodicity L and the computed wetted solid-fraction ro[subscript s] are found to be consistent with existing analytic predictions.
MIT Department
Massachusetts Institute of Technology. Department of Chemical Engineering
Massachusetts Institute of Technology. Department of Mechanical Engineering
Terms of Use
Article is available under a Creative Commons license
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1039/c3sm50445j
