Article
Chemistry, Physical
Xin He, Ben-Xi Zhang, Shuo-Lin Wang, Yi-Feng Wang, Yan-Ru Yang, Xiao-Dong Wang, Duu-Jong Lee
Summary: The study reveals that under an external electric field, a nanodroplet on pillar-arrayed surfaces can transition from an initial Cassie state to a partial wetting state, and eventually to a Wenzel state. The free-energy landscape shows multiple local energy minima, corresponding to multiple metastable states. It is found that the wetting transition from Wenzel to Cassie state is spontaneous only when the Cassie droplet is in a global energy minimum configuration.
JOURNAL OF MOLECULAR LIQUIDS
(2022)
Article
Chemistry, Analytical
Zhantao Wang, Xiaojuan Liu, Li Wang, Cunlu Zhao, Danfeng Zhou, Jiazheng Wei
Summary: This study reports for the first time the phenomenon of droplet trampolining using electrowetting and provides consistent results through experiments and simulations. The findings are important for applications that require vertical transportation of droplets or detachment of droplets from solid surfaces.
Article
Chemistry, Multidisciplinary
Fuqiang Chu, Zhongyuan Ni, Dongsheng Wen, Yanhui Feng, Shaokang Li, Lei Jiang, Zhichao Dong
Summary: Liquid manipulation plays a crucial role in daily life and future technological processes. This study demonstrates a droplet-impact-induced liquid film sculpture strategy on a microstructured heterowettable surface, which can precisely sculpt a liquid film into any desired pattern. The liquid film sculpture exhibits self-propulsion and high construction speed, making it suitable for various applications such as no-spray printing, painting, cleaning, and drawing.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Physical
Run Liu, Yi-Bo Wang, Shu-Wei Yang, Han-Wu Liu, Yan-Ru Yang, Xiao-Dong Wang, Duu-Jong Lee
Summary: Through molecular dynamics (MD) simulations, the study investigates the bouncing dynamics of nanodroplets impacting a hydrophobic surface under electric fields with various field strengths and directions. The impacts of the electric fields on the bouncing dynamics of nanodroplets are significant, especially when the field strength exceeds 0.08 V A-1 and the field direction is altered.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2021)
Article
Chemistry, Physical
Georg Schnell, Christian Polley, Robert Thomas, Stephan Bartling, Johannes Wagner, Armin Springer, Hermann Seitz
Summary: In this study, the researchers used a customized instrument to investigate the lateral adhesion forces on femtosecond laser-structured surfaces. They found that the droplet motion was significantly influenced by the chemical and topographical surface features. The droplet mobility was classified into static, transfer, and kinetic regimes, which is crucial for designing surfaces with extreme wetting characteristics.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2023)
Article
Engineering, Chemical
Ajit Kumar, Manabendra Pathak
Summary: In this study, the impact of droplets on hydrophobic and superhydrophobic surfaces was investigated using electrowetting technique. The results showed that the dynamics of the droplet were strongly influenced by the voltage amplitude, frequency, and surface hydrophobicity. Increasing the voltage amplitude enhanced the spreading of the droplet but reduced its recoiling rate, leading to partial or complete suppression of droplet rebound. The combination of voltage amplitude, frequency, and surface hydrophobicity affected the degree of droplet rebound suppression.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Chemistry, Physical
Nicolas T. Theodorou, Alexandros G. Sourais, Athanasios G. Papathanasiou
Summary: This study investigates the electrowetting-induced detachment of droplets from solid surfaces through simulation and experiments. The results show that optimal detachment can be achieved when the application of voltage is synchronized with the spreading time of the droplet. The droplet's ability to detach depends mainly on its contact angle, viscosity, and applied voltage.
Article
Physics, Multidisciplinary
Jing Lou, SongLin Shi, Chen Ma, CunJing Lv, QuanShui Zheng
Summary: In this study, a new wetting state called the suspended penetration wetting state was identified, where the droplet can penetrate the micropillars on textured surfaces without touching the base. Experimental results showed that the droplet can spontaneously recover to the initial wetting state when the external pressure is removed.
SCIENCE CHINA-PHYSICS MECHANICS & ASTRONOMY
(2021)
Article
Multidisciplinary Sciences
Sandra Benter, Adam Jonsson, Jonas Johansson, Lin Zhu, Evangelos Golias, Lars-Erik Wernersson, Anders Mikkelsen
Summary: This study proposes the use of lithographically defined metal stacks to regulate the surface concentrations of freely diffusing synthesis elements on compound semiconductors. The geometric control of Indium droplet formation on Indium Arsenide surfaces is achieved, and the behaviours of Aluminium and Palladium as flux control agents are investigated. The study demonstrates that lithographic metal patterns can be used to control the formation of large droplets during the heating of compound semiconductors, providing a new way to steer bottom-up synthesis on-chip.
NATURE COMMUNICATIONS
(2023)
Article
Thermodynamics
Xuan Gao, Yakang Xia, Ri Li
Summary: Experimental investigation on transient flow boiling of ethanol droplets impinging on heated copper plates reveals that microstructured surfaces can achieve boiling at lower temperatures and increasing surface roughness decreases the Leidenfrost temperature. Additionally, it is found that surface microstructures slightly reduce the Nukiyama temperature. This work is relevant to high temperature boiling regimes in two-phase spray cooling applications.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2021)
Article
Thermodynamics
Jizu Lyu, Linsong Gao, Yang Li, Minli Bai, Dongdong Gao, Zhang Yongfei
Summary: The study experimentally investigates the dynamics of droplet impact and evaporation on regular micro-grooved and irregular microstructured surfaces. The results show that surface temperature has little effect on the spreading factor curves in the first spreading phase, but significantly impacts evaporation time at higher temperatures. Irregular microstructured surfaces provide more active nucleation sites, contributing to shorter evaporation time compared to regular micro-grooved and flat surfaces.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2021)
Article
Nanoscience & Nanotechnology
Soumei Baba, Kenichiro Sawada, Kohsuke Tanaka, Atsushi Okamoto
Summary: This study focused on the hierarchical nano/microstructure of Euphorbia myrsinites leaves and successfully mimicked the structure artificially to provide important insights for the development of new engineering materials.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Thermodynamics
Shinan Chang, Haifeng Qi, Shu Zhou, Yinglin Yang
Summary: In this study, the freezing characteristics of water droplets on different surfaces were experimentally investigated. The results showed that different materials have different effects on the freezing characteristics of water droplets. Superhydrophobic surfaces exhibited a better anti-freezing performance compared to hydrophilic surfaces. Additionally, the observed singular jet phenomena indicated that surface temperature significantly affects the freezing rate of water droplets.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Materials Science, Multidisciplinary
Asif Raiyan, Behrouz Mohammadian, Hossein Sojoudi
Summary: This study investigates the wettability of superhydrophobic nanoporous surfaces in condensation and freezing environments, finding that carbon nanotube microstructured pillars with favorable topological configuration exhibit excellent anti-condensation and anti-icing properties.
Article
Engineering, Chemical
Hyeon Woo Son, Jung Bin Yang, Dong Rip Kim
Summary: Demisters with high water separation efficiencies are crucial for performance enhancement in thermal desalination. Microstructured surfaces inspired by nature have shown potential to significantly increase water separation by enhancing water capturing and transporting features. However, there is still a lack of experimental investigation on the performance enhancement of demisters with these functional surfaces.
Article
Thermodynamics
Srivathsan Sudhakar, Justin A. Weibel, Feng Zhou, Ercan M. Dede, Suresh Garimella
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2020)
Article
Thermodynamics
Gaurav Patankar, Justin A. Weibel, Suresh Garimella
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2020)
Article
Thermodynamics
Kalind Baraya, Justin A. Weibel, Suresh Garimella
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2020)
Article
Physics, Applied
Enakshi D. Wikramanayake, Jordin Perry, Vaibhav Bahadur
APPLIED PHYSICS LETTERS
(2020)
Article
Chemistry, Physical
Enakshi Wikramanayake, Vaibhav Bahadur
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2020)
Article
Mechanics
Ankur Miglani, Justin A. Weibel, Suresh Garimella
Summary: This study experimentally assesses the effect of thermal coupling between parallel microchannels on flow maldistribution caused by the Ledinegg instability and compares the results to prior theoretical predictions. The data show that thermal coupling reduces flow maldistribution range and severity, providing evidence that channel-to-channel thermal coupling can redistribute heat load and reduce flow maldistribution under extreme conditions.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2021)
Article
Engineering, Manufacturing
Kalind Baraya, Justin A. Weibel, Suresh V. Garimella
Summary: An easy-to-use representation of vapor chambers with effective anisotropic properties has been developed for accurate simulation of their operation, independent of boundary conditions and heat input. This approach helps match the thermal responses of the vapor chamber to a full, physical simulation of phase change and energy transport in the vapor core.
IEEE TRANSACTIONS ON COMPONENTS PACKAGING AND MANUFACTURING TECHNOLOGY
(2021)
Article
Thermodynamics
Taylor P. Allred, Justin A. Weibel, Suresh Garimella
Summary: This study investigates the dynamic contact angles during bubble growth and departure, showing that the receding contact angle plays a crucial role in the early stages of bubble growth. Additionally, the advancing contact angle affects the departure morphology, calling for a redefinition of wettability classifications based on dynamic contact angles in the context of boiling.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2021)
Article
Mechanics
Ankur Miglani, Justin A. Weibel, Suresh V. Garimella
Summary: This study investigates flow maldistribution between two parallel microchannels caused by Ledinegg instability, which leads to uneven flow distribution and temperature difference between channels as power increases. The results show that in extreme conditions, a significant proportion of flow is directed to the channel operating in the single-phase liquid regime, while the other channel receives only a small portion of the flow.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2021)
Review
Engineering, Electrical & Electronic
Manojkumar Lokanathan, Palash Acharya, Abdelhamid Ouroua, Shannon M. Strank, Robert E. Hebner, Vaibhav Bahadur
Summary: Dielectric materials with high thermal conductivity have been the focus of research for enhancing performance in electronics packaging and thermal management. Recent developments in nanocomposite dielectric materials have shown promising results, but the assessment of their practical applications requires consideration of various thermal, mechanical, and electrical properties in addition to high TC.
PROCEEDINGS OF THE IEEE
(2021)
Article
Chemistry, Multidisciplinary
Aritra Kar, Palash Vadiraj Acharya, Awan Bhati, Ashish Mhadeshwar, Pradeep Venkataraman, Timothy A. Barckholtz, Hugo Celio, Filippo Mangolini, Vaibhav Bahadur
Summary: Gas hydrates offer solutions in various applications, but their formation is limited by long induction times for nucleation. This study introduces a simple and environmentally friendly technique using magnesium to significantly promote the nucleation of CO2 hydrates. Magnesium triggers nucleation almost instantaneously, with induction times less than 1 minute and nucleation rates 3000 times higher than baseline. Insights into the chemistry behind magnesium-based promotion, including the role of magnesium-water-CO2 gas three-phase line, porous oxide layers, and magnesium alloys, were uncovered.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2021)
Article
Chemistry, Multidisciplinary
Aritra Kar, Awan Bhati, Manojkumar Lokanathan, Vaibhav Bahadur
Summary: The study found that controlling the interfacial chemistry at the three-phase line can influence ice nucleation, with silicone oil and almond oil replacing air at the water-air interface speeding up the nucleation process and leading to higher ice nucleation temperatures at the aluminum-water-silicone oil (or almond oil) interface. The model suggests that three-phase contact lines usually provide a stronger driving force than heterogeneous nucleation, accelerating the nucleation process.
