Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 23 for “"Superhydrophobic surface"”.
-
Passive and active approaches to sustained turbulent hydrodynamic drag reduction using superhydrophobic surfaces
Superhydrophobic surfaces have been shown to trap a pocket of air (or a "plastron") in between the features of their rough texture when submerged in water. A partial slip condition is created at the interface between the water and the submerged body, allowing for a reduction in skin friction drag. …
-
Developing an active, high-heat-flux thermal management strategy for power electronics via jumping-droplet phase-change cooling
… from a copper oxide (CuO) nanostructured superhydrophobic surface to the transistor hot spots by applying electric fields between the condensing surface and an electrically floated circuit (directly to the transistor) or a guard ring (surrounding the transistor). Heat transfer measurements …
-
Design and construction of rigs for studying surface condensation and creating anodized metal oxide surfaces
… design and construction of a rig for studying surface condensation and a rig for creating anodized metal oxides (AMOs). The condensation rig characterizes condensation for different surfaces; this is done with the use of known heat transfer principles to calculate characteristic heat fluxes and …
-
ADDITIVE MANUFACTURING OF SUPERHYDROPHOBIC STAINLESS STEEL COMPOSITES
… that achieve these goals by demonstrating superhydrophobic surface behaviors. Composite materials made up of 316L stainless steel powders and various concentrations of boron nitride nanotubes (BNNT) were mixed and printed via laser powder directed energy deposition (LP-DED). The additively …
-
Droplet deposition on hydrophobic surfaces for agricultural sprays
… a novel idea based on the modification of the surface of the plant. By precipitating opposite polyelectrolytes, in-situ, we create sparse pinning sites that pin the contact lines of the impacting droplets from the spray and prevent them from bouncing off. We first study the behavior of the …
-
Enhanced coalescence-induced jumping droplet departure
Water vapor condensation on superhydrophobic surfaces has received much attention in recent years due to its ability to shed water droplets at length scales three decades smaller than the capillary length (~ 1mm) via coalescence induced droplet jumping. Jumping-droplet condensation has been …
-
Superhydrophobic membranes for membrane distillation and crystallization
… form of low permeate flux and membrane wetting. Superhydrophobic modifications to the membrane surface could potentially overcome this issue. While superhydrophobic surfaces have been known to display anti-fouling properties, how this affects membrane distillation performance is still not well …
-
Condensation heat transfer on nanoengineered surfaces
… related studies with the aim of developing a surface that promotes robust dropwise condensation. Due to their remarkably low droplet adhesion, superhydrophobic surfaces were investigated for application to dropwise condensation. Although precise model superhydrophobic surfaces were necessary …
-
Characterization of the robustness of superhydrophobic surfaces during condensation
… power plants in their power generation cycles. Superhydrophobic surfaces can potentially improve the heat transfer due to condensation when compared to the untreated surfaces typically used in condensers. This can improve the efficiency of power plants by up to 3%. These surfaces are made by …
-
Dynamical Phase-Change Phenomena
… is the wetting or dewetting transitions of a superhydrophobic surface, in which the phase residing within the surface structure switches between vapor and liquid. Phase transition phenomena frequently occur in our daily life; examples include: a ``liquid'' to ``solid'' transition when cars …
-
Enhanced Laminar Convective Heat Transfer using Microstructured Superhydrophobic Surfaces
… the complex interactions between a solid surface and a fluid in motion relative to the surface. For many cases, the classical no slip boundary condition holds true. However, there are a subset of situations where this assumption is not valid, and slip between the surface and fluid must be …
-
The Effects of Surface Topography on Droplet Evaporation and Condensation
… phase-change heat transfer enhancement, surface chemistry and energy system optimization. Especially, in the past two decades, the rapid development of the nature-inspired non-wetting surfaces has promoted the applications of droplet-based phase change phenomena in various scenarios. …
-
Effects of micro- and nano-scale surface geometry on behaviors of live cells and liquid droplets
As the scale of the surface texture responsible for superhydrophobicity becomes similar to the size of a droplet, simple models based on homogeneity assumptions begin to break down. In order to better understand these discrete phenomena, we first create a unique model with the finite element …
-
Liquid-infused slippery surfaces for air-conditioning and refrigeration applications
Liquid-infused surfaces have drawn a lot of attention due to their excellent water repellency. A method is presented for creating a durable liquid-infused surface (LISs) on aluminum surfaces to minimize the water retention and enhance thermal-hydraulic performance for air-conditioning and …
-
Droplet levitation and underwater plastron restoration using aerophilic surface textures
… of active components in liquids and responsive surfaces to resist the wetting of water on solid surface textures. When a superhydrophobic surface comes into contact with water, it traps a thin layer of air (plastron) within its surface texture. This entrapped air is advantageous for reducing the …
-
Specialized Inter-Particle Interaction Lbm For Patterned Superhydrophobic Surfaces
… INTER-PARTICLE INTERACTION LBM FOR PATTERNED SUPERHYDROPHOBIC SURFACES</p> <p>by</p> <p>AMAL S. YAGUB</p> <p>ABSTRACT:</p> <p> Superhydrophobic surface characteristics are important in many industrial applications, ranging from the textile to the military. It was observed that surfaces …
-
Aircraft Anti-Icing Analysis: Water Droplet Dynamics Under High-Frequency Atomization and Superhydrophobic Effects
… and combines it with the passive method of surface roughness variation by fabricating superhydrophobic surfaces. The study analyzes the droplet impact at 3 speeds. The impact is recorded with high-speed imaging using selected resonant frequencies (between 6 kHz and 25.6 kHz) to determine the …
-
Dynamic wetting of soft materials and applications of dynamic tensiometry
Surfaces and interfaces pervade our world and understanding the phenomena that occur at them is imperative for a wide range of commercial and industrial applications. This thesis focuses on investigating the influence of physical and chemical parameters on surface wettability and characterizing …
-
Electrostatic charging of jumping droplets on superhydrophobic nanostructured surfaces : fundamental study and applications
… environmental control. Recent advancements in surface engineering have offered new opportunities to enhance condensation heat transfer by drastically changing the wetting properties of the condenser surface. Specifically, the development of superhydrophobic surfaces has been pursued to enhance …
-
3D integration of micro- and nanostructures into bio-analytical devices
… stamp and imprinted structures on the bottom surface of the 3D channel. A modified 3D molding process which is called 3D nanomolding is developed which allows nanopatterning the surface of small microfeatures. Using 3D nanomolding process and solvent assisted bonding microdevices with no side, …
Page 1 of 2