Focal Plane Shift Imaging for the Analysis of Multi-Droplet Jumping
| العنوان: | Focal Plane Shift Imaging for the Analysis of Multi-Droplet Jumping |
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| المؤلفون: | Nenad Miljkovic, Yuehan Xu, Jae Min Chun, Hyeongyun Cha |
| المصدر: | Journal of Heat Transfer. 139 |
| بيانات النشر: | ASME International, 2017. |
| سنة النشر: | 2017 |
| مصطلحات موضوعية: | Materials science, business.industry, Mechanical Engineering, Carbon nanotube, Condensed Matter Physics, medicine.disease_cause, Surface energy, Visualization, law.invention, Physics::Fluid Dynamics, Cardinal point, Jumping, Optics, Mechanics of Materials, law, Physics::Atomic and Molecular Clusters, medicine, General Materials Science, business |
| الوصف: | High speed images of coalescence induced three-droplet jumping on a nanostructured superhydrophobic carbon nanotube (CNT) surface are presented (θaapp ≈ 173º). When two or more droplets coalesce on a nanostructured superhydrophobic surface, the resulting droplet can jump away from the surface due to the release of excess surface energy. To more easily study the jumping phenomena, we have developed focal plane shift imaging (FPSI) to determine both jumping speed and direction. Figure 1(a) shows a schematic of the FPSI concept. A high speed camera was attached to an upright optical microscope, and samples were horizontally mounted on a cold stage. Initial conditions were obtained by moving the focal plane to be coincident with the middle of the droplets prior to coalescence (Figure 1b). Then the focal plane was shifted above the droplets by a known distance (Figure 1c), followed by measurement of the time taken for the jumping droplet to pass through the shifted focal plane (Figure 1d). By analyzing the initial and final conditions of the departing droplet for multiple three-droplet coalescence events, the three-droplet jumping droplet speed was determined (Figure 2b). Experimentally measured jumping speeds determined by the FPSI imaging technique show good agreement with three-droplet inertial capillary scaling (Figure 2b, dotted line, equation inset). The FPSI visualization technique provides a novel imaging platform for the study of complex multi-droplet jumping-droplet phenomena. |
| تدمد: | 1528-8943 0022-1481 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_________::233219655cfd43572d99826dd01e8449 https://doi.org/10.1115/1.4035573 |
| رقم الأكسشن: | edsair.doi...........233219655cfd43572d99826dd01e8449 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 15288943 00221481 |
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