Jia-Cai Huang, Tian-Yang Han, Jie Zhang, Ming-Jiu Ni
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引用次数: 0
Abstract
Theoretical modeling is proposed to predict the maximum spreading of water-based ferrofluid droplets impacting upon dry surfaces influenced by a vertical magnetic field. Constructed on the principle of energy balance, this model demonstrates excellent agreement with numerical findings across various impact velocities, contact angles, and magnetic strengths. Notably, as magnetic field strength escalates, magnetic forces prevail over viscous and capillary forces, exerting a significant influence on spreading dynamics and diminishing the maximum spreading diameter of ferrofluid droplets if the impacting shape is spherical. However, for freely falling droplets, the shape becomes prolate before impacting and the promoted surface energy balances the magnetic inhibitory effect on droplet spreading, thus resulting in an almost unchanged maximum spreading diameter. By postulating complete conversion of initial kinetic energy into magnetic energy, a scaling law is derived for maximum spreading diameter under extremely high magnetic fields. Further interpolation with viscous dissipation and capillary effects enables universal rescaling under diverse impact conditions. Through comparison with numerical outcomes, the validity of our theoretical model is affirmed, establishing a balanced formula between distinct energy components for predicting maximum spreading diameter of ferrofluid droplets accurately.
期刊介绍:
Langmuir is an interdisciplinary journal publishing articles in the following subject categories:
Colloids: surfactants and self-assembly, dispersions, emulsions, foams
Interfaces: adsorption, reactions, films, forces
Biological Interfaces: biocolloids, biomolecular and biomimetic materials
Materials: nano- and mesostructured materials, polymers, gels, liquid crystals
Electrochemistry: interfacial charge transfer, charge transport, electrocatalysis, electrokinetic phenomena, bioelectrochemistry
Devices and Applications: sensors, fluidics, patterning, catalysis, photonic crystals
However, when high-impact, original work is submitted that does not fit within the above categories, decisions to accept or decline such papers will be based on one criteria: What Would Irving Do?
Langmuir ranks #2 in citations out of 136 journals in the category of Physical Chemistry with 113,157 total citations. The journal received an Impact Factor of 4.384*.
This journal is also indexed in the categories of Materials Science (ranked #1) and Multidisciplinary Chemistry (ranked #5).