California Polytechnic State University - San Luis Obispo
Iowa State College
AAR Aerospace Consulting, LLC
Western Michigan University
Linfield College
University of Colorado, Boulder
High Throughput, Automated Prediction Of Focusing Patterns For Inertial Microfluidics,
2019
Iowa State University
High Throughput, Automated Prediction Of Focusing Patterns For Inertial Microfluidics, Aditya Kommajosula, Jeong-Ah Kim, Wonhee Lee, Baskar Ganapathysubramanian
Baskar Ganapathysubramanian
Visual inspections for identifying focusing points in inertial microfluidic flows are prone to misinterpreting stable locations and focusing shifts in the case of non-trivial focusing patterns. We develop and deploy an approach for automating the calculation of focusing patterns for a general channel geometry, and thereby reduce the dependence on empirical/visual procedures to confirm the presence of stable locations. We utilize concepts from interpolation theory (to represent continuous force-fields using discrete points), and stability theory to identify "basins of attraction" and quantitatively identify stable equilibrium points. Our computational experiments reveal that predicting equilibrium points accurately requires upto ×10-20 times ...
High Throughput, Automated Prediction Of Focusing Patterns For Inertial Microfluidics,
2019
Iowa State University
High Throughput, Automated Prediction Of Focusing Patterns For Inertial Microfluidics, Aditya Kommajosula, Jeong-Ah Kim, Wonhee Lee, Baskar Ganapathysubramanian
Mechanical Engineering Publications
Visual inspections for identifying focusing points in inertial microfluidic flows are prone to misinterpreting stable locations and focusing shifts in the case of non-trivial focusing patterns. We develop and deploy an approach for automating the calculation of focusing patterns for a general channel geometry, and thereby reduce the dependence on empirical/visual procedures to confirm the presence of stable locations. We utilize concepts from interpolation theory (to represent continuous force-fields using discrete points), and stability theory to identify "basins of attraction" and quantitatively identify stable equilibrium points. Our computational experiments reveal that predicting equilibrium points accurately requires upto ×10-20 times ...
Shape-Design For Stabilizing Micro-Particles In Inertial Microfluidic Flows,
2019
Iowa State University
Shape-Design For Stabilizing Micro-Particles In Inertial Microfluidic Flows, Aditya Kommajosula, Daniel Stoecklein, Dino Di Carlo, Baskar Ganapathysubramanian
Mechanical Engineering Publications
Design of microparticles which stabilize at the centerline of a channel flow when part of a dilute suspension is examined numerically for moderate Reynolds numbers (10≤Re≤80). Stability metrics for particles with arbitrary shapes are formulated based on linear-stability theory. Particle shape is parametrized by a compact, Non-Uniform Rational B-Spline (NURBS)-based representation. Shape-design is posed as an optimization problem and solved using adaptive Bayesian optimization. We focus on designing particles for maximal stability at the channel-centerline robust to perturbations. Our results indicate that centerline-focusing particles are families of characteristic "fish"/"bottle"/"dumbbell"-like shapes, exhibiting fore-aft asymmetry. A ...
Call For Abstracts - Resrb 2019, July 8-9, Wrocław, Poland,
2018
Wojciech Budzianowski Consulting Services
Call For Abstracts - Resrb 2019, July 8-9, Wrocław, Poland, Wojciech M. Budzianowski
Wojciech Budzianowski
No abstract provided.
Investigation Of Flow Disturbances And Multi-Directional Wall Shear Stress In The Stenosed Carotid Artery Bifurcation Using Particle Image Velocimetry,
2018
The University of Western Ontario
Investigation Of Flow Disturbances And Multi-Directional Wall Shear Stress In The Stenosed Carotid Artery Bifurcation Using Particle Image Velocimetry, Amanda L. Dicarlo
Electronic Thesis and Dissertation Repository
Hemodynamics and shear forces are associated with pathological changes in the vascular wall and its function, resulting in the focal development of atherosclerosis. Flow complexities that develop in the presence of established plaques create environments favourable to thrombosis formation and potentially plaque rupture leading to stroke. The carotid artery bifurcation is a common site of atherosclerosis development. Recently, the multi-directional nature of shear stress acting on the endothelial layer has been highlighted as a risk factor for atherogenesis, emphasizing the need for accurate measurements of shear stress magnitude as well direction. In the absence of comprehensive patient specific datasets numerical ...
Heat Transfer Comparison Of Varied Pebble Sizes And Packing Arrangements In A Pebble-Bed Reactor,
2018
Kennesaw State University
Heat Transfer Comparison Of Varied Pebble Sizes And Packing Arrangements In A Pebble-Bed Reactor, Julian Spangler
Georgia Undergraduate Research Conference (GURC)
Pebble bed reactors are more cost efficient when heat transfer is optimized. In a pebble-bed reactor, optimizing heat transfer involves the analysis of complex flow. Therefore, computational fluid dynamics was used to simulate fluid movement in a structured cubic packing arrangement with a purpose in finding an optimal size of pebbles that will yield the fastest rate of heat transfer. The simple cubic pebble arrangement was used to determine if pebble size was key to optimizing heat transfer in the reactor. More complex arrangements of pebbles were used as comparison to the simple cubic packing in order to determine if ...
Entry Of A Sphere Into A Water-Surfactant Mixture And The Effect Of A Bubble Layer,
2018
Utah State University
Entry Of A Sphere Into A Water-Surfactant Mixture And The Effect Of A Bubble Layer, Nathan Speirs, Mohammad Mansoor, Randy Hurd, Saberul Sharker, W. G. Robinson, B. J. Williams, Tadd T. Truscott
Mechanical and Aerospace Engineering Faculty Publications
A rigid sphere entering a liquid bath does not always produce an entrained air cavity. Previous experimental work shows that cavity formation, or the lack thereof, is governed by fluid properties, wetting properties of the sphere, and impact velocity. In this study, wetting steel spheres are dropped into a water-surfactant mixture with and without passing through a bubble layer first. Surprisingly, in the case of a water-surfactant mixture without a bubble layer, the critical velocity for cavity formation becomes radius dependent. This occurs due to dynamic surface tension effects, with the local surface tension in the splash increasing during surface ...
Fluted Films,
2018
Utah State University
Fluted Films, Nathan B. Speirs, Mohammad M. Mansoor, Jesse Belden, Randy C. Hurd, Zhao Pan, Tadd T. Truscott
Mechanical and Aerospace Engineering Faculty Publications
This paper is associated with a poster winner of a 2017 APS/DFD Milton van Dyke Award for work presented at the DFD Gallery of Fluid Motion. The original poster is available from the Gallery of Fluid Motion, https://doi.org/10.1103/APS.DFD.2017.GFM.P0030
Interface Model Of Pem Fuel Cell Membrane Steady-Dtate Behavior,
2018
Old Dominion University
Interface Model Of Pem Fuel Cell Membrane Steady-Dtate Behavior, Russell L. Edwards, Ayodeji Demuren
Mechanical & Aerospace Engineering Faculty Publications
Modeling works which simulate the proton-exchange membrane fuel cell with the computational fluid dynamics approach involve the simultaneous solution of multiple, interconnected physics equations for fluid flows, heat transport, electrochemical reactions, and both protonic and electronic conduction. Modeling efforts vary by how they treat the physics within and adjacent to the membrane-electrode assembly (MEA). Certain approaches treat the MEA not as part of the computational domain, but rather an interface connecting the anode and cathode computational domains. These approaches may lack the ability to consistently model catalyst layer losses and MEA ohmic resistance. This work presents an upgraded interface formulation ...
Experimental Measurements Of Human Cough Airflows From Healthy Subjects And Those Infected With Respiratory Viruses,
2018
The University of Western Ontario
Experimental Measurements Of Human Cough Airflows From Healthy Subjects And Those Infected With Respiratory Viruses, Nicholas Dudalski
Electronic Thesis and Dissertation Repository
Research concerning person-to-person respiratory virus transmission is required to develop reliable, evidence-based infection prevention and control measures. Experimental studies of human coughs were comprehensively critiqued from the point of view of methodologies, aerodynamics, droplet dispersion and virology. Particle image velocimetry (PIV) and hot-wire anemometry (HWA) measurements were conducted at x=1 m away from the mouth of human subjects to develop a model for cough flow behaviour at greater distances from the mouth than those studied previously. Experiments were conducted for sick subjects who had presented with influenza-like illness, together with a cohort of healthy subjects. Biological aerosol sampling was ...
Reversible Motion In A Contact Line,
2018
California Polytechnic State University, San Luis Obispo
Reversible Motion In A Contact Line, Audrey Profeta, Esmeralda Orozco, Juan A. Ortiz Salazar, Dani Medina, Nathan C. Keim
STAR (STEM Teacher and Researcher) Presentations
When a body of liquid sits on a surface, an irregular border between the wet and dry regions of the surface exists, called the contact line. Driving this contact line back and forth repeatedly can change its shape.We use a syringe pump to cyclically infuse and withdraw a predetermined volume of water, and take photos of the contact line after each cycle. Comparing these images to each other determines if the contact line is returning to the same shape. We find that below a critical value of infused volume, after many cycles the contact line reaches a steady state ...
The Periglacial Landscape Of Mars: Insight Into The 'Decameter-Scale Rimmed Depressions' In Utopia Planitia,
2018
The University of Western Ontario
The Periglacial Landscape Of Mars: Insight Into The 'Decameter-Scale Rimmed Depressions' In Utopia Planitia, Arya Bina
Electronic Thesis and Dissertation Repository
Currently, Mars appears to be in a ‘frozen’ and ‘dry’ state, with the clear majority of the planet’s surface maintaining year-round sub-zero temperatures. However, the discovery of features consistent with landforms found in periglacial environments on Earth, suggests a climate history for Mars that may have involved freeze and thaw cycles. Such landforms include hummocky, polygonised, scalloped, and pitted terrains, as well as ice-rich deposits and gullies, along the mid- to high-latitude bands, typically with no lower than 20o N/S. The detection of near-surface and surface ice via the Phoenix lander, excavation of ice via recent impact cratering ...
Stability Of The Interface Between Two Immiscible Liquids During Injection Into A Tapered Hele-Shaw Cell,
2018
Purdue University
Stability Of The Interface Between Two Immiscible Liquids During Injection Into A Tapered Hele-Shaw Cell, Zihao Lin, Ivan C. Christov, Daihui Lu
The Summer Undergraduate Research Fellowship (SURF) Symposium
In the early twentieth century, petroleum and mining engineers noticed that water does not displace oil uniformly. This phenomenon, when water penetrates through oil, is now known as viscous fingering. This discovery and the following extensive research have contributed to enhancing oil recovery. In this paper, we describe a numerical study conducted on the stability of the interface between two immiscible liquids in converging and diverging Hele-Shaw cells with varying gradients. Hele-Shaw cells are narrow flow geometries that mimic the properties of a porous medium with fixed permeability. By using computational tools built on the OpenFOAM platform, the multiphase flow ...
Fuel Flow Reduction Impact Analysis Of Drag Reducing Film Applied To Aircraft Wings,
2018
Southern Methodist University
Fuel Flow Reduction Impact Analysis Of Drag Reducing Film Applied To Aircraft Wings, Damon Resnick, Chris Donlan, Nimish Sakalle, Cody Pinkerman
SMU Data Science Review
In this paper, we present an analysis of flight data in order to determine whether the application of the Edge Aerodynamix Conformal Vortex Generator (CVG), applied to the wings of aircraft, reduces fuel flow during cruising conditions of flight. The CVG is a special treatment and film applied to the wings of an aircraft to protect the wings and reduce the non-laminar flow of air around the wings during flight. It is thought that by reducing the non-laminar flow or vortices around and directly behind the wings that an aircraft will move more smoothly through the air and provide a ...
Electro-Drop Bouncing In Low-Gravity,
2018
Portland State University
Electro-Drop Bouncing In Low-Gravity, Erin Stivers Schmidt
Dissertations and Theses
We investigate the dynamics of spontaneous jumps of water drops from electrically charged superhydrophobic dielectric substrates during a sudden step reduction in gravity level. In the brief free-fall environment of a drop tower, with a non-homogeneous external electric field arising due to dielectric surface charges (with surface potentials 0.4-1.8 kV), body forces acting on the jumped drops are primarily supplied by polarization stress and Coulombic attraction instead of gravity. This electric body force leads to a drop bouncing behavior similar to well-known phenomena in 1-g0, though occurring for much larger drops (~0.5 mL). We show ...
Determining The Activation Energy Of Glucose Syrup Using The Arrhenius Equation,
2018
Queensland Academy SMT
Determining The Activation Energy Of Glucose Syrup Using The Arrhenius Equation, Utkarsh Sharma
The International Student Science Fair 2018
This experiment finds the activation energy of corn syrup using the Arrhenius equation. This was done through a simple experiment of dropping a ball into corn syrup and measuring its terminal velocity. From this, the viscosity could be derived, through the use of rearrangement of Newton’s First Law. The temperature of the corn syrup was also varied through the use of a microwave by raising it to 50 degrees Celsius. It is known that the more viscous a liquid is, the greater the activation energy for the liquid, which is essentially the energy barrier that a molecule has to ...
Finding Activation Energy Of Corn Syrup,
2018
Illinois Math and Science Academy
Finding Activation Energy Of Corn Syrup, Utkarsh Sharma
The International Student Science Fair 2018
This experiment finds the activation energy of corn syrup using the Arrhenius equation. This was done through a simple experiment of dropping a ball into corn syrup and measuring its terminal velocity. From this, the viscosity could be derived, through the use of rearrangement of Newton’s First Law. The temperature of the corn syrup was also varied through the use of a microwave by raising it to 50 degrees Celsius. It is known that the more viscous a liquid is, the greater the activation energy for the liquid, which is essentially the energy barrier that a molecule has to ...
Computer Design Of Microfluidic Mixers For Protein/Rna Folding Studies,
2018
University of Massachusetts Amherst
Computer Design Of Microfluidic Mixers For Protein/Rna Folding Studies, Venkatesh Inguva, Sagar V. Kathuria, Osman Bilsel, Blair James Perot
Open Access Articles
Kinetic studies of biological macromolecules increasingly use microfluidic mixers to initiate and monitor reaction progress. A motivation for using microfluidic mixers is to reduce sample consumption and decrease mixing time to microseconds. Some applications, such as small-angle x-ray scattering, also require large ( > 10 micron) sampling areas to ensure high signal-to-noise ratios and to minimize parasitic scattering. Chaotic to marginally turbulent mixers are well suited for these applications because this class of mixers provides a good middle ground between existing laminar and turbulent mixers. In this study, we model various chaotic to marginally turbulent mixing concepts such as flow turning, flow ...
Elementary Computational Fluid Dynamics Using Finite-Difference Methods,
2018
Union College - Schenectady, NY
Elementary Computational Fluid Dynamics Using Finite-Difference Methods, Jason Turner, Scott Labrake
Honors Theses
Fluids permeate all of human existence, and fluid dynamics serves as a rich field of research for many physicists. Although the mathematics involved in studying fluids tends to get complicated, the physical intuition gained through daily exposure to such systems bridges the gap between abstract calculations and their physical meaning. We discuss the mathematical treatment and simulations of fluid flows found in everyday life, such as flow in a cavity and through a pipe. Our discussions follow the example set by several notable texts, referenced in the document.
A 3d Simulation Of Leukocyte Adhesion In Blood Flow,
2018
Western Michigan University
A 3d Simulation Of Leukocyte Adhesion In Blood Flow, Tai-Hsien Wu
Dissertations
It has been widely acknowledged that further understanding about the dynamics between blood cells and blood flow can help us gain more knowledge about the causes of diseases and discover more effective treatments. Examples of such dynamics include red blood cell (RBC, or erythrocyte) aggregation, white blood cell (WBC, or leukocyte) margination, and WBC extravasation. WBC extravasation is an important multiple-step process in the inflammatory response and therefore has drawn considerable attention over the past two decades. In this multiple-step process, a WBC undergoes at least four steps, including capture, rolling, firm adhesion, and transmigration, and each step is influenced ...
