Effect of Micropillar Spacing and Temperature of Substrate on Contact Angle Dynamics
| Autor: | Khellil Sefiane, Gail Duursma, Jonathan G. Terry, John Christy, Coinneach Mackenzie-Dover |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
Fluid Flow and Transfer Processes
Work (thermodynamics) Materials science 020209 energy Mechanical Engineering Dynamics (mechanics) 02 engineering and technology Substrate (electronics) Condensed Matter Physics Microstructure Physics::Fluid Dynamics Contact angle 020303 mechanical engineering & transports 0203 mechanical engineering 0202 electrical engineering electronic engineering information engineering Composite material |
| Zdroj: | Dover, C, Duursma, G, Sefiane, K, Christy, J & Terry, J 2018, ' Effect of micropillar spacing and temperature of substrate on contact angle dynamics ', Heat Transfer Engineering . https://doi.org/10.1080/01457632.2018.1443246 |
| ISSN: | 1521-0537 0145-7632 |
| DOI: | 10.1080/01457632.2018.1443246 |
| Popis: | Contact angle dynamics of droplets deposited on a structured surface were studied in this work and the effects of substrate microstructure and temperature were investigated. Microstructures consisting of uniformly-sized, cubic micropillars with varying pillar spacings were constructed by microfabrication. Droplets (of the order of tens of microlitres in volume) were deposited on these surfaces and dynamic contact angles were observed using various techniques. Advancing and receding contact angles were measured using tilting of the surfaces or by injection and aspiration of fluid from a horizontal droplet by syringe. Droplets on these surfaces appeared to be mainly in the Wenzel state. Contact angle hysteresis was obtained as a function of pillar spacing or, equivalently, surface roughness. Depinning force was deduced and a linear dependence on maximal three phase contact line was found. The techniques of tilting the surface on which the droplet was deposited and uniformly increasing and reducing the volume of the droplet via the syringe both gave the same contact angle hysteresis for a given micropillar spacing. The effect of temperature was then assessed using a heated tilting plate. Contact angle hysteresis was found to increase with temperature. Further work to elucidate mechanisms governing this dependence will be undertaken. |
| Databáze: | OpenAIRE |
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