Open Access. Powered by Scholars. Published by Universities.®

Fluid Dynamics Commons

Open Access. Powered by Scholars. Published by Universities.®

431 Full-Text Articles 607 Authors 97765 Downloads 45 Institutions

All Articles in Fluid Dynamics

Faceted Search

431 full-text articles. Page 1 of 14.

Nmr Study Of The New Magnetic Superconductor Cak ( Fe 0.951 Ni 0.049 ) 4 As 4 : Microscopic Coexistence Of The Hedgehog Spin-Vortex Crystal And Superconductivity, Qing-Ping Ding, William R. Meier, A. E. Böhmer, S. L. Bud’ko, Paul C. Canfield, Yuji Furukawa 2018 Iowa State University and Ames Laboratory

Nmr Study Of The New Magnetic Superconductor Cak ( Fe 0.951 Ni 0.049 ) 4 As 4 : Microscopic Coexistence Of The Hedgehog Spin-Vortex Crystal And Superconductivity, Qing-Ping Ding, William R. Meier, A. E. Böhmer, S. L. Bud’Ko, Paul C. Canfield, Yuji Furukawa

Paul C. Canfield

The coexistence of a new-type antiferromagnetic (AFM) state, the so-called hedgehog spin-vortex crystal (SVC), and superconductivity (SC) is evidenced by an 75 As nuclear magnetic resonance study on single-crystalline CaK ( Fe 0.951 Ni 0.049 ) 4 As 4 . The hedgehog SVC order is clearly demonstrated by the direct observation of internal magnetic induction along the c axis at the As1 site (close to K) and a zero net internal magnetic induction at the As2 site (close to Ca) below an AFM ordering temperature T N ∼ 52 K. The nuclear spin-lattice relaxation rate 1 / T 1 shows a distinct decrease ...


Call For Abstracts - Resrb 2018, June 18-20, Brussels, Belgium, Wojciech M. Budzianowski 2017 Wojciech Budzianowski Consulting Services

Call For Abstracts - Resrb 2018, June 18-20, Brussels, Belgium, Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.


Registration Form Resrb 2018, Wojciech M. Budzianowski 2017 Wojciech Budzianowski Consulting Services

Registration Form Resrb 2018, Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.


Abstract Template Resrb 2018, Wojciech M. Budzianowski 2017 Wojciech Budzianowski Consulting Services

Abstract Template Resrb 2018, Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.


Towards Eulerian Modeling Of A Polydisperse Evaporating Spray Under Realistic Internal-Combustion-Engine Conditions, Oguz Emre, Rodney O. Fox, Marc Mossot, Stephane de Chaisemartin, Stephane Jay, Frederique Laurent 2017 Laboratoire EM2C

Towards Eulerian Modeling Of A Polydisperse Evaporating Spray Under Realistic Internal-Combustion-Engine Conditions, Oguz Emre, Rodney O. Fox, Marc Mossot, Stephane De Chaisemartin, Stephane Jay, Frederique Laurent

Rodney O. Fox

To assist the industrial engine design process, 3-D computational fluid dynamics simulations are widely used, bringing a comprehension of the underlying physics unattainable from experiments. However, the multiphase flow description involving a liquid fuel jet injected into the chamber is still in its early stages of development. There is a pressing need for a spray model that is time efficient and accurately describes the cloud of fuel and droplet dynamics downstream of the injector. Eulerian descriptions of the spray are well adapted to this highly unsteady configuration. The challenge is then to capture accurately both the evaporating spray polydispersity and ...


Solution Of Population Balance Equations In Applications With Fine Particles: Mathematical Modeling And Numerical Schemes, Tan Trung Nguyen, Frédérique Laurent, Rodney O. Fox, Marc Massot 2017 Université Paris-Saclay

Solution Of Population Balance Equations In Applications With Fine Particles: Mathematical Modeling And Numerical Schemes, Tan Trung Nguyen, Frédérique Laurent, Rodney O. Fox, Marc Massot

Rodney O. Fox

The accurate description and robust simulation, at relatively low cost, of global quantities (e.g. number density or volume fraction) as well as the size distribution of a population of fine particles in a carrier fluid is still a major challenge for many applications. For this purpose, two types of methods are investigated for solving the population balance equation with aggregation, continuous particle size change (growth and size reduction), and nucleation: the extended quadrature method of moments (EQMOM) based on the work of Yuan et al.[52]and a hybrid method (TSM) between the sectional and moment methods, considering two ...


Nmr Study Of The New Magnetic Superconductor Cak ( Fe 0.951 Ni 0.049 ) 4 As 4 : Microscopic Coexistence Of The Hedgehog Spin-Vortex Crystal And Superconductivity, Qing-Ping Ding, William R. Meier, A. E. Böhmer, S. L. Bud’ko, Paul C. Canfield, Yuji Furukawa 2017 Iowa State University and Ames Laboratory

Nmr Study Of The New Magnetic Superconductor Cak ( Fe 0.951 Ni 0.049 ) 4 As 4 : Microscopic Coexistence Of The Hedgehog Spin-Vortex Crystal And Superconductivity, Qing-Ping Ding, William R. Meier, A. E. Böhmer, S. L. Bud’Ko, Paul C. Canfield, Yuji Furukawa

Ames Laboratory Accepted Manuscripts

The coexistence of a new-type antiferromagnetic (AFM) state, the so-called hedgehog spin-vortex crystal (SVC), and superconductivity (SC) is evidenced by an 75 As nuclear magnetic resonance study on single-crystalline CaK ( Fe 0.951 Ni 0.049 ) 4 As 4 . The hedgehog SVC order is clearly demonstrated by the direct observation of internal magnetic induction along the c axis at the As1 site (close to K) and a zero net internal magnetic induction at the As2 site (close to Ca) below an AFM ordering temperature T N ∼ 52 K. The nuclear spin-lattice relaxation rate 1 / T 1 shows a distinct decrease ...


Dynamic Self-Assembly And Self-Organized Transport Of Magnetic Micro-Swimmers, Gašper Kokot, German Kolmakov V, Igor S. Aranson, Alexey Snezhko 2017 Argonne National Laboratory

Dynamic Self-Assembly And Self-Organized Transport Of Magnetic Micro-Swimmers, Gašper Kokot, German Kolmakov V, Igor S. Aranson, Alexey Snezhko

Publications and Research

We demonstrate experimentally and in computer simulations that magnetic microfloaters can self-organize into various functional structures while energized by an external alternating (ac) magnetic field. The structures exhibit self-propelled motion and an ability to carry a cargo along a pre-defined path. The morphology of the self-assembled swimmers is controlled by the frequency and amplitude of the magnetic field.


Faraday-Talbot Effect From A Circular Array Of Pillars, Jessica J. Pilgram 2017 California Polytechnic State University, San Luis Obispo

Faraday-Talbot Effect From A Circular Array Of Pillars, Jessica J. Pilgram

Physics

When an oil bath is vertically oscillating with an acceleration above some critical value, known as the Faraday threshold, the bath surface becomes unstable and nonlinear standing wave patterns emerge. One phenomenon that has been observed above the Faraday threshold is the formation of Faraday-Talbot carpets, resulting from near-field diffraction. The optical Talbot effect occurs when a monochromatic wave passes through a diffraction grating. In the near-field, the formation of self- images is observed at integer multiples of what is known as the Talbot length. These two-dimensional patterns have various applications including X-ray imaging and atom and particle trapping. Two- ...


A High Quality, Eulerian 3d Fluid Solver In C++, LeJon Anthony McGowan 2017 California Polytechnic State University, San Luis Obispo

A High Quality, Eulerian 3d Fluid Solver In C++, Lejon Anthony Mcgowan

Computer Science

Fluids are a part of everyday life, yet are one of the hardest elements to properly render in computer graphics. Water is the most obvious entity when thinking of what a fluid simulation can achieve (and it is indeed the focus of this project), but many other aspects of nature, like fog, clouds, and particle effects. Real-time graphics like video games employ many heuristics to approximate these effects, but large-scale renderers aim to simulate these effects as closely as possible.

In this project, I wish to achieve effects of the latter nature. Using the Eulerian technique of discrete grids, I ...


A Mathematical Analysis Of Drug Dissolution In The Usp Flow Through Apparatus, David McDonnell, Deirdre M. D'Arcy, Lawrence J. Crane, Brendan Redmond 2017 Dublin Institute of Technology

A Mathematical Analysis Of Drug Dissolution In The Usp Flow Through Apparatus, David Mcdonnell, Deirdre M. D'Arcy, Lawrence J. Crane, Brendan Redmond

Articles

This paper applies boundary layer theory to the process of drug dissolution in the USP (United States Pharmacopeia) Flow Through Apparatus. The mass transfer rate from the vertical planar surface of a compact within the device is examined. The theoretical results obtained are then compared with those of experiment. The paper also examines the effect on the dissolution process caused by the interaction between natural and forced convection within the apparatus and the introduction of additional boundaries.


Simulation Of Driven Elastic Spheres In A Newtonian Fluid, Shikhar M. Dwivedi 2017 The University of Western ontario

Simulation Of Driven Elastic Spheres In A Newtonian Fluid, Shikhar M. Dwivedi

Electronic Thesis and Dissertation Repository

Simulations help us test various restrictions/assumptions placed on physical systems that would otherwise be difficult to efficiently explore experimentally. For example, the Scallop Theorem, first stated in 1977, places limitations on the propulsion mechanisms available to microscopic objects in fluids. In particular, the theorem states that when the viscous forces in a fluid dominate the inertial forces associated with a physical body, such a physical body cannot generate propulsion by means of reciprocal motion. The focus of this thesis is to firstly, explore an adaptive Multiple-timestep(MTS) scheme for faster molecular dynamics(MD) simulations, and secondly, use hybrid MD-LBM ...


Instrument Design Optimization With Computational Methods, Michael H. Moore 2017 Old Dominion University

Instrument Design Optimization With Computational Methods, Michael H. Moore

Physics Theses & Dissertations

Using Finite Element Analysis to approximate the solution of differential equations, two different instruments in experimental Hall C at the Thomas Jefferson National Accelerator Facility are analyzed. The time dependence of density fluctuations from the liquid hydrogen (LH2) target used in the Qweak experiment (2011-2012) are studied with Computational Fluid Dynamics (CFD) and the simulation results compared to data from the experiment. The 2.5 kW liquid hydrogen target was the highest power LH2 target in the world and the first to be designed with CFD at Jefferson Lab. The first complete magnetic field simulation of the Super High ...


High Fidelity Cfd Modeling Of Natural Ventilation In A Solar House, Mirka Deza, Baskar Ganapathysubramanian, Shan He, Ulrike Passe 2017 Iowa State University

High Fidelity Cfd Modeling Of Natural Ventilation In A Solar House, Mirka Deza, Baskar Ganapathysubramanian, Shan He, Ulrike Passe

Ulrike Passe

Natural ventilation is an important factor in the design of sustainable buildings; it has the potential to improve air quality, while providing thermal comfort at reduced energy costs. Computational fluid dynamics (CFD) simulations provide comprehensive information on the internal flow pattern and can be used as a design tool. The present work offers insight of natural ventilation in a fully functional building, namely, the solar facility Interlock House in Iowa. Ventilation in the house is studied during summer months with some of its furniture included. The results show quantitative agreement between numerical simulations and experiments of vertical temperature profiles for ...


High Fidelity Cfd Modeling Of Natural Ventilation In A Solar House, Mirka Deza, Baskar Ganapathysubramanian, Shan He, Ulrike Passe 2017 Iowa State University

High Fidelity Cfd Modeling Of Natural Ventilation In A Solar House, Mirka Deza, Baskar Ganapathysubramanian, Shan He, Ulrike Passe

Baskar Ganapathysubramanian

Natural ventilation is an important factor in the design of sustainable buildings; it has the potential to improve air quality, while providing thermal comfort at reduced energy costs. Computational fluid dynamics (CFD) simulations provide comprehensive information on the internal flow pattern and can be used as a design tool. The present work offers insight of natural ventilation in a fully functional building, namely, the solar facility Interlock House in Iowa. Ventilation in the house is studied during summer months with some of its furniture included. The results show quantitative agreement between numerical simulations and experiments of vertical temperature profiles for ...


Hawking Radiation And Classical Tunneling: A Numerical Study, Dmitriy Zhigunov 2017 College of William and Mary

Hawking Radiation And Classical Tunneling: A Numerical Study, Dmitriy Zhigunov

Undergraduate Honors Theses

Unruh [1] demonstrated that black holes have an analogy in acoustics. Under this analogy the acoustic event horizon is defined by the set of points in which the local background flow exceeds the local sound speed. In past work [2], we demonstrated that under a white noise source, the acoustic event horizon will radiate at a thermal spectrum via a classical tunneling process. In this work, I summarize the theory presented in [2] and nondimensionalize it in order to reduce the dynamical equations to one parameter, the coupling coefficient η2. Since η2 is the sole parameter of the system, we ...


Characterization Of The Shock Wave Structure In Water, Emilie Teitz 2017 Marquette University

Characterization Of The Shock Wave Structure In Water, Emilie Teitz

Master's Theses (2009 -)

The scientific community is interested in furthering the understanding of shock wave structures in water, given its implications in a wide range of applications; from researching how shock waves penetrate unwanted body tissues to studying how humans respond to blast waves. Shock wave research on water has existed for over five decades. Previous studies have investigated the shock response of water at pressures ranging from 1 to 70 GPa using flyer plate experiments. This report differs from previously published experiments in that the water was loaded to shock pressures ranging from 0.36 to 0.70 GPa. The experiment also ...


Effect Of Interstitial Fluid On The Fraction Of Flow Microstates That Precede Clogging In Granular Hoppers, Juha Koivisto, Douglas J. Durian 2017 University of Pennsylvania

Effect Of Interstitial Fluid On The Fraction Of Flow Microstates That Precede Clogging In Granular Hoppers, Juha Koivisto, Douglas J. Durian

Department of Physics Papers

We report on the nature of flow events for the gravity-driven discharge of glass beads through a hole that is small enough that the hopper is susceptible to clogging. In particular, we measure the average and standard deviation of the distribution of discharged masses as a function of both hole and grain sizes. We do so in air, which is usual, but also with the system entirely submerged under water. This damps the grain dynamics and could be expected to dramatically affect the distribution of the flow events, which are described in prior work as avalanche-like. Though the flow is ...


Removal Of Chlorine From Chlorine-Nitrogen Mixture In A Film Of Liquid Water, Sarwan S. Sandhu 2017 University of Dayton

Removal Of Chlorine From Chlorine-Nitrogen Mixture In A Film Of Liquid Water, Sarwan S. Sandhu

Sarwan S. Sandhu

In industry there are many examples of absorption of a gas with or without chemical reaction in the liquid phase. In physical absorption, a particular gaseous component is removed from a gas mixture due to its larger solubility in the liquid phase solvent. The removal of butane and pentane from a refinery gas mixture by a heavy oil in the liquid phase is an example of physical absorption. In absorption with chemical reaction, the gaseous component to be removed transfers across the gas-liquid interface due to a difference in the bulk chemical potentials or concentrations in the two phases. The ...


Higher-Harmonic Collective Modes In A Trapped Gas From Second-Order Hydrodynamics, William E. Lewis, Paul Romatschke 2017 University of Colorado Boulder

Higher-Harmonic Collective Modes In A Trapped Gas From Second-Order Hydrodynamics, William E. Lewis, Paul Romatschke

University Libraries Open Access Fund Supported Publications

Utilizing a second-order hydrodynamics formalism, the dispersion relations for the frequencies and damping rates of collective oscillations as well as spatial structure of these modes up to the decapole oscillation in both two- and three- dimensional gas geometries are calculated. In addition to higher-order modes, the formalism also gives rise to purely damped 'non-hydrodynamic' modes. We calculate the amplitude of the various modes for both symmetric and asymmetric trap quenches, finding excellent agreement with an exact quantum mechanical calculation. We find that higher-order hydrodynamic modes are more sensitive to the value of shear viscosity, which may be of interest for ...


Digital Commons powered by bepress