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Register a new userStable Oleoplaned Slippery Surfaces on Biomimetically Patterned Templates
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Added by
Saumyadwip Bandyopadhyay
Publication date
2018
fields
Physics
and research's language is
English
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With the advent of the technology of the oleoplaned slippery surfaces as the better solution to self-cleaning, anti fouling and self-healing smart surfaces, the stability of the oil layer on the surfaces has caught a great deal of attention from the research community. Rose petals irrespective of its superhydrophobic nature exhibits a very high adhesion owing to the hierarchical structures and can thus serve as an excellent surface to obtain a stable oil film. Also, with gradual covering of the rose petal structures by the oil the change in the adhesion force is observed to decrease and an increase in the film thickness beyond a certain height causes cloaking of the droplet and thus presents us with an optimum thickness which can give us a stable oil film and also exhibit high degree of slipperiness. The findings can be applied for further applications in droplet based microfluidics, as a low energy actuation surface, or as a self-healing and self-cleaning surface.
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A dynamic wetting problem is studied for a moving thin fiber inserted in fluid and with a chemically inhomogeneous surface. A reduced model is derived for contact angle hysteresis by using the Onsager principle as an approximation tool. The model is simple and captures the essential dynamics of the contact angle. From this model we derive an upper bound of the advancing contact angle and a lower bound of the receding angle, which are verified by numerical simulations. The results are consistent with the quasi-static results. The model can also be used to understand the asymmetric dependence of the advancing and receding contact angles on the fiber velocity, which is observed recently in physical experiments reported in Guan et al Phys. Rev. Lett. 2016.
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