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Showing 1 to 20 of 22 for “"Droplet Impact"”.
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Computational Modeling of Droplet Impact Dynamics on Solid Substrates
… computational model is developed to simulate the impact dynamics of a droplet on solid substrates with the purpose of predicting the droplet spreading characteristics over time. Previous studies focused on finding relations between the impact parameters and outcome dynamics. A modified approach …
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Droplet Impact on a Solid Surface: Analytical Modeling and Experimentation for Spreading Phase
A normal droplet impacting a flat, stationary, solid surface exhibits symmetric spreading. A key aspect of this symmetric spreading, particularly during deposition at low Weber numbers, is the formation of a rim along the lamella edge. The rim is crucial for predicting maximum spreading, and its …
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Investigating Droplet Impact Dynamics on Engineered Surfaces: Effects of Roughness, Wettability, and Prospects for Anti-Icing Applications
Understanding how water droplets interact with engineered surfaces can help address critical challenges such as ice accumulation on airplanes, wind turbines, and power lines, which can pose safety risks and result in costly damage. This research examines how surface properties, including roughness …
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Droplet-based Two-phase Thermal Management
… new advanced thermal management methods. Droplet-based two-phase thermal management technologies are considered promising solutions to conquer the cooling challenges in the electronic industries. The heat transfer behavior of droplets is based on several important fundamental processes, …
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Droplet Rebound and Atomization Characteristics of Vibrating Surfaces
… of ice or snow on the wing surface due to impact with supercooled droplets when passing through clouds at high altitudes, causing loss of lift obtained by the wings. It was found that droplet impact characteristics are dependent on droplet size, surface roughness, surface material …
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Development of a Metal Droplet Generator for Studying Impact Dynamics
<p>Metal droplet-based 3D printing is a popular technique used for creating complex structures and multi-material components. However, accuracy is a significant challenge in this process due to complex thermal and dynamic behaviors that can negatively affect the final workpiece. To improve …
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A three-dimensional printing machine to facilitate observation of printing phenomena
… Three Dimensional Printing machine, the droplet impact observation station, which this thesis documents. The requirements of the machine are presented, the realized design and operation of the machined described, the results of initial tests of operation presented and areas for further …
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The influence of vapor pressure on droplet contact dynamics on smooth surfaces.
Droplet impact experiments were performed with different fluids using Total Internal Reflection Microscopy (TIRM) on a smooth surface to gain insight into the mechanism for the air film failure of volatile liquids. Several parameters were varied including the impact velocity and droplet …
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Investigation into smoothed particle hydrodynamics for non-newtonian droplet modelling
Droplet splatter dynamics is an important study in the field of forensics since a crime event can produce many blood stains. Understanding the origins of the blood stains from pure observations is very difficult because much of the information about the impact is lost. A theoretical model is …
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Phase transfer in a collision between a droplet and solid spheres
The hydrodynamics of a liquid droplet impinging on a particle is of direct relevance to many engineering applications. The mechanism of heat and mass transfer during the droplet solid collision is essential to the design and operation of many industrial systems. However, very limited systemic …
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Feasibility study of rapid prototyping using the uniform droplet spray process
… of rapid prototyping using the Uniform Droplet Spray (UDS) process. Straight and stable liquid metal jets are crucial requirements in the application of UDS to rapid prototyping. Methods to maintain the jet straight and stable were developed. Hardware improvements include an auxiliary …
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Engineering physico-chemical interactions across drug delivery, agriculture and carbon capture
… a less viscous fluid. Second, by cloaking spray droplets in minute quantities of plant oils (≤ 1wt%), we enhance energy dissipation during droplet impact on hydrophobic surfaces and demonstrate a 5x reduction in pesticide waste on a variety of plant leaves. Finally, mist-scale droplets and space …
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Impact Dynamics of Water Droplet on Solid Surfaces: Effect of Impact Reynolds Number, Hydrophobicity, Surface Roughness and Temperature
… are dealing with is aircraft icing. The impact and freezing process of a water droplet on a cold surface has been investigated over time in order to develop preventative methods for avoiding icing. In the present study, we examined the behavior of a water droplet impacting on an aluminum …
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Modeling Droplet Impingement Dynamics on Micropillar-Arrayed Viscoelastic Substrates Through Microgeometry-Free and Multiscale Methods
The droplet impact dynamics on micropillar-arrayed viscoelastic substrates has been thoroughly investigated by two distinct modeling methods, i.e., microgeometry-free and multiscale modeling methods. The viscoelasticity of the micropillar-arrayed substrate is characterized by a five-parameter …
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Understanding the Formation Mechanism of Plasma-sprayed Ni and Ni20Cr Splats through Experimental and Numerical Study
… coatings, the molten (or semi-molten) droplets impact on the substrate surface, spread and solidify to form splats with various morphologies. Splats serve as the basic building blocks of the bulk coating where their morphology changes and splat-substrate interactions are critical for …
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Impact and Departure Dynamics of Droplets and Bubbles
Droplets and bubbles are important for understanding natural phenomena such as falling raindrops, airborne disease transmission, and plant respiration systems, and also for engineering contexts such as semiconductor fabrication, nuclear power plants, and electronics cooling. However, still, more …
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Effects of Two-Phase Flow in a Multistage Centrifugal Compressor
… known to be affected by the ingestion of liquid droplets in the compressor. In these multiphase flows, the liquid and the vapor phase are tightly coupled. Therefore the interphase heat, mass and momentum transfer as well as droplet dynamics including droplet breakup and droplet-wall interactions …
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Meaningful descriptions of thixotropy and extensibility for yield-stress fluid drop impact on thin films
Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2022-11-15 without embargo terms
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An investigation of droplets and films falling over horizontal tubes
… and in particular, the behavior and role of droplets in horizontal-tube banks. Only axisymmetric cases, such as the formation of droplets from capillaries and jets, are generally considered in the literature. Flow visualization experiments were conducted on two horizontal-tube banks with …
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Aircraft Anti-Icing Analysis: Water Droplet Dynamics Under High-Frequency Atomization and Superhydrophobic Effects
… the weight. Still, complexities arise from water droplets freezing at supercooled levels. A novel approach uses the structure's vibration to induce atomization, a proposed active anti-icing method using high-frequency Piezoelectric Transducer (PZT) vibration and combines it with the passive method …
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