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

Fluid Dynamics Commons™

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

783 Full-Text Articles 1,363 Authors 368,018 Downloads 100 Institutions

All Articles in Fluid Dynamics

Faceted Search

783 full-text articles. Page 29 of 31.

Flow Over A Traveling Wavy Foil With A Passively Flapping Flat Plate, Nansheng Liu, Yan Peng, Youwen Liang, Xiyun Lu 2012 Old Dominion University

Flow Over A Traveling Wavy Foil With A Passively Flapping Flat Plate, Nansheng Liu, Yan Peng, Youwen Liang, Xiyun Lu

Mathematics & Statistics Faculty Publications

Flow over a traveling wavy foil with a passively flapping flat plate has been investigated using a multiblock lattice Boltzmann equation and the immersed boundary method. The foil undergoes prescribed undulations in the lateral direction and the rigid flat plate has passive motion determined by the fluid structure interaction. This simplified model is used to study the effect of the fish caudal fin and its flexibility on the locomotion of swimming animals. The flexibility of the caudal fin is modeled by a torsion spring acting about the pivot at the conjuncture of the wavy foil and the flat plate. The …


Electrokinetic Properties Of Lipid And Sarcoplasmic Reticulum Membranes In Aqueous Electrolyte And In The Presence Of Lipophilic Ions, Laura Elizabeth Satterfield 2012 Portland State University

Electrokinetic Properties Of Lipid And Sarcoplasmic Reticulum Membranes In Aqueous Electrolyte And In The Presence Of Lipophilic Ions, Laura Elizabeth Satterfield

Dissertations and Theses

The purpose of this study is the characterization of the membrane-water interfaces of both sarcoplasmic reticulum membrane (SR) and charged lipid bilayers under varied properties of the surrounding aqueous solution. In this work we studied the electrokinetic properties of liposomes and SR vesicles as well as the interaction of lipophilic ions with these membranes. The study of electrokinetic properties is based on the measurements of electrophoretic mobility of SR membrane vesicles and PC/PG liposomes. Electrophoretic mobility of SR vesicles was measured as a function of ionic strength for six pH values (pH 4.0, 4.7, 5.0, 6.0, 7.5, and 9.0). Electrophoretic …


Compound Capillary Rise, Mark M. Weislogel 2012 Portland State University

Compound Capillary Rise, Mark M. Weislogel

Mechanical and Materials Engineering Faculty Publications and Presentations

Irregular conduits, complex surfaces, and porous media often manifest more than one geometric wetting condition for spontaneous capillary flows. As a result, different regions of the flow exhibit different rates of flow, all the while sharing common dynamical capillary pressure boundary conditions. The classic problem of sudden capillary rise in tubes with interior corners is revisited from this perspective and solved numerically in the self-similar visco-capillary limit à laLucas–Washburn. Useful closed-form analytical solutions are obtained in asymptotic limits appropriate for many practical flows in conduits containing one or more interior corner. The critically wetted corners imbibe fluid away from …


Unitary Qubit Lattice Gas Representation Of 2d And 3d Quantum Turbulence, George Vahala, Bo Zhang, Jeffrey Yepez, Linda L. Vahala, Min Soe 2012 Old Dominion University

Unitary Qubit Lattice Gas Representation Of 2d And 3d Quantum Turbulence, George Vahala, Bo Zhang, Jeffrey Yepez, Linda L. Vahala, Min Soe

Electrical & Computer Engineering Faculty Publications

No abstract provided.


Formation Of Organized Nanostructures From Unstable Bilayers Of Thin Metallic Liquids, Mikhail Khenner, Sagar Yadavali, Ramki Kalyanaraman 2011 Western Kentucky University

Formation Of Organized Nanostructures From Unstable Bilayers Of Thin Metallic Liquids, Mikhail Khenner, Sagar Yadavali, Ramki Kalyanaraman

Mathematics Faculty Publications

Dewetting of pulsed-laser irradiated, thin (< 20 nm), optically reflective metallic bilayers on an optically transparent substrate with a reflective support layer is studied within the lubrication equations model. A steady-state bilayer film thickness (h) dependent temperature profile is derived based on the mean substrate temperature estimated from the elaborate thermal model of transient heating and melting/freezing. Large thermocapillary forces are observed along the plane of the liquid-liquid and liquid-gas interfaces due to this h-dependent temperature, which, in turn, is strongly influenced by the h-dependent laser light reflection and absorption. Consequently the dewetting is a result of the competition between thermocapillary and intermolecular forces. A linear analysis of the dewetting length scales established that the non-isothermal calculations better predict the experimental results as compared to the isothermal case within the bounding Hamaker coefficients. Subsequently, a computational non-linear dynamics study of the dewetting pathway was performed for Ag/Co and Co/Ag bilayer systems to predict the morphology evolution. We found that the systems evolve towards formation of different morphologies, including core-shell, embedded, or stacked nanostructure morphologies.


Peristaltic Induced Flow Of A Two-Layered Suspension In Non-Uniform Channel, Amit Medhavi, Dharmendra Singh, Ajay S. Yadav, Ramesh S. Gautam 2011 Kamla Nehru Institute of Technology

Peristaltic Induced Flow Of A Two-Layered Suspension In Non-Uniform Channel, Amit Medhavi, Dharmendra Singh, Ajay S. Yadav, Ramesh S. Gautam

Applications and Applied Mathematics: An International Journal (AAM)

Peristaltic transport of a two-layered particulate suspension in a non-uniform channel has been investigated. The coupled differential equations for both the fluid and the particle phases in the central as well as in the peripheral layers have been solved and the expression for the flow rate, the pressure rise and the friction force has been derived. The results obtained are discussed both qualitatively and quantitatively in brief. The significance of the particle concentration as well as the peripheral layer has been well explained.


Mathematical Modeling Of Peristaltic Flow Of Chyme In Small Intestine, Daniel N. Riahi, Ranadhir Roy 2011 University of Texas-Pan American

Mathematical Modeling Of Peristaltic Flow Of Chyme In Small Intestine, Daniel N. Riahi, Ranadhir Roy

Applications and Applied Mathematics: An International Journal (AAM)

Mathematical models based on axisymmetric Newtonian incompressible fluid flow are studied for the peristaltic flow of chyme in the small intestines, which is an axisymmetric cylindrical tube. The flow is modeled more realistically modeled by assuming that the peristaltic rush wave is a non-periodic mode composed of two sinusoidal waves of different wavelengths, which propagate at the same speed along the outer boundary of the tube. Both cases of flow in a tube and in an annulus that are modeled and investigated in the present paper correspond respectively to the cases of flow of chyme in the small intestine in …


The Power Series Solution Of Fingering Phenomenon Arising In Fluid Flow Through Homogeneous Porous Media, Kinjal Patel, M. N. Mehta, Twinkle R. Patel 2011 S.V. National Institute of Technology

The Power Series Solution Of Fingering Phenomenon Arising In Fluid Flow Through Homogeneous Porous Media, Kinjal Patel, M. N. Mehta, Twinkle R. Patel

Applications and Applied Mathematics: An International Journal (AAM)

The present paper deals with the approximate solution of the fingering phenomenon occurring when water is pushed into oil in homogeneous porous media with capillary mean pressure. The phenomenon is formulated mathematically as a water-oil double phase flow problem. The solution of the nonlinear partial differential equation of fingering phenomenon has been discussed in terms of the power series using appropriate boundary conditions for any timeT>0 . The solution is in ascending power series which represents saturation of injected fluid in fingering phenomenon & its graphical and numerical presentation is given in MATLAB coding.


Stability Of Stratified Couple-Stress Dusty Fluid In The Presence Of Magnetic Field Through Porous Medium, Vivek Kumar 2011 University of Petroleum & Energy Studies (UPES)

Stability Of Stratified Couple-Stress Dusty Fluid In The Presence Of Magnetic Field Through Porous Medium, Vivek Kumar

Applications and Applied Mathematics: An International Journal (AAM)

The combined effect of magnetic field and dust particles on the stability of a stratified couplestress fluid through a porous medium is considered. For stable stratification, the system is found to be stable for disturbances of all wave numbers. The magnetic field succeeds in stabilizing the potentially unstable stratifications for a certain wave-number range which were unstable in the absence of the magnetic field. Discussions of oscillatory and non-oscillatory modes are also made.


Nonlinear Progressive Wave Equation For Stratified Atmospheres, B. Edward McDonald, Andrew A. Piacsek 2011 Naval Research Laboratory

Nonlinear Progressive Wave Equation For Stratified Atmospheres, B. Edward Mcdonald, Andrew A. Piacsek

All Faculty Scholarship for the College of the Sciences

The nonlinear progressive wave equation (NPE) [McDonald and Kuperman, J. Acoust. Soc. Am. 81, 1406–1417 (1987)] is expressed in a form to accommodate changes in the ambient atmospheric density, pressure, and sound speed as the time-stepping computational window moves along a path possibly traversing significant altitude differences (in pressure scale heights). The modification is accomplished by the addition of a stratification term related to that derived in the 1970s for linear range-stepping calculations and later adopted into Khokhlov-Zabolotskaya-Kuznetsov-type nonlinear models. The modified NPE is shown to preserve acoustic energy in a ray tube and yields analytic similarity solutions for …


Left Ventricular Assist Devices: Engineering Design Considerations, Marwan A. Simaan, Eduardo Divo, George Faragallah, Yu Wang 2011 University of Central Florida

Left Ventricular Assist Devices: Engineering Design Considerations, Marwan A. Simaan, Eduardo Divo, George Faragallah, Yu Wang

Publications

Patients with end-stage congestive heart failure awaiting heart transplantation often wait long periods of time (300 days or more on the average) before a suitable donor heart becomes available. The medical community has placed increased emphasis on the use of Left Ventricular Assist Devices or LVADs that can substitute for, or enhance, the function of the natural heart while the patient is waiting for the heart transplant (Poirier, 1997; Frazier & Myers, 1999). Essentially, a rotary LVAD is a pump that operates continuously directing blood from the left ventricle into the aorta by avoiding the aortic valve. Generally speaking, the …


Turbulence And Wave Dynamics Across Gas–Liquid Interfaces, Shahrdad Sajjadi, Julian Hunt, Stephen Belcher, Derek Stretch, John Clegg 2011 Embry-Riddle Aeronautical University

Turbulence And Wave Dynamics Across Gas–Liquid Interfaces, Shahrdad Sajjadi, Julian Hunt, Stephen Belcher, Derek Stretch, John Clegg

Publications

Mechanisms are reviewed here for the distortion of turbulent flows near thin density interfaces and their effects on transfer processes across them. Firstly the results of rapid distortion calculations show how the in homogeneous eddy structure depends on whether the turbulence is generated above or below the interface, or in both regions. The flow is unstratified and the buoyancy forces are stable and strong enough relative to the inertial forces that the interface is continuous. It is shown that as the surface blocks the vertical turbulent eddy motions, horizontal straining motions are induced which affect the surface viscous layers and …


Small Reynolds Number Steady Flow Past A Sphere With A Source At Its Centre, Sunil Datta, Shanu Singhal 2011 Lucknow University

Small Reynolds Number Steady Flow Past A Sphere With A Source At Its Centre, Sunil Datta, Shanu Singhal

Applications and Applied Mathematics: An International Journal (AAM)

In this paper we study the steady flow, at low Reynolds number R , past a pervious sphere with a source at its centre. Assuming the source strength s also to be small, we use the method of matched asymptotic expansions to generate the inner and outer solutions pertaining to the problem. Graphs depicting the streamlines have been drawn to exhibit the effects of s and R . Also, the expression of the calculated drag experienced by the sphere shows that the effect of a source (s > o) is to decrease the drag.


Similarity Solution For Flow Of A Micro-Polar Fluid Through A Porous Medium, Kh. S. Mekheimer, R. E. Abo-Elkhair, S. Z. -A. Husseny, A. T. Ali 2011 Al-Azhar University

Similarity Solution For Flow Of A Micro-Polar Fluid Through A Porous Medium, Kh. S. Mekheimer, R. E. Abo-Elkhair, S. Z. -A. Husseny, A. T. Ali

Applications and Applied Mathematics: An International Journal (AAM)

The equations of two dimensional incompressible steady micro-polar fluid flows through a porous medium are studied. Lie group analysis is employed and the solutions corresponding to the translational symmetry are developed. A boundary value problem is investigated and the results are sketched graphically. The effect on the flow of the porosity coefficient of the porous medium and the micro-polar parameters are observed.


Peristaltic Induced Flow Of A Particulate Suspension In A Non-Uniform Geometry, Amit Medhavi, U. K. Singh 2011 Kamla Nehru Institute of Technology

Peristaltic Induced Flow Of A Particulate Suspension In A Non-Uniform Geometry, Amit Medhavi, U. K. Singh

Applications and Applied Mathematics: An International Journal (AAM)

The flow induced by sinusoidal peristaltic waves of a particle-fluid suspension in a twodimensional diverging channel under low Reynolds number and long wavelength approximation has been investigated. The analytical expression for the flow characteristics-the flow rate, pressure rise and friction force have been derived. Moreover, we present some results concerning the dependence of these quantities on the geometrical parameters.


Analysis Of Flow Fields In A Flexible Tube With Periodic Constriction, Swati Mukhopadhyay, Prativa R. De, Mani S. Mandal, G. C. Layek 2011 The University of Burdwan

Analysis Of Flow Fields In A Flexible Tube With Periodic Constriction, Swati Mukhopadhyay, Prativa R. De, Mani S. Mandal, G. C. Layek

Applications and Applied Mathematics: An International Journal (AAM)

Numerical techniques based on pressure-velocity formulation have been adopted to solve approximately, the governing equations for viscous flows through a tube (simulating an artery) with a periodic constriction. The effect of the constriction as well as the rigid of the tube, on the flow characteristics, and its consequences for arterial disease is the focus of this investigation. The unsteady incompressible Navier-Stokes equations are solved by using the finite-difference technique in staggered grid distribution. The haemodynamic factors like wall shear stress, pressure and velocity are analyzed through their graphical representations. Maximum resistance is attained in case of rigid stenosed tube rather …


Human Powered Helicopter: Observing The Impacts Of Ground Effect And Intermeshed Rotors, Shane Stowe 2011 California Polytechnic State University - San Luis Obispo

Human Powered Helicopter: Observing The Impacts Of Ground Effect And Intermeshed Rotors, Shane Stowe

Physics

No abstract provided.


Ferrofluids, James Patt 2011 California Polytechnic State University - San Luis Obispo

Ferrofluids, James Patt

Physics

Ferrofluids are truly fascinating. Technologically savvy artists have been able to capture the human imagination with little but a judicious application of a magnetic field. The substance seems to defy gravity, flowing and shaping itself seemingly like magic (see Figure 1). The true magic, however, is the vast range of properties that this intrinsically simple substance can exhibit. It can vary its viscosity given the strength of the magnetic field. It can draw heat away from an over worked mechanical component. It can even split a beam of light in two. It’s hard to imagine what kind of strange and …


Mathematical Modeling And Computation Of Channel Flow Over Discrete Structures, Rolando J. Olivares, Daniel N. Riahi 2011 University of Texas-Pan American

Mathematical Modeling And Computation Of Channel Flow Over Discrete Structures, Rolando J. Olivares, Daniel N. Riahi

Applications and Applied Mathematics: An International Journal (AAM)

In this paper mathematical modeling and computation of channel flow over small discrete structures are carried out under some reasonable conditions. A mathematical model for such a flow problem, which is based on a relevant system of partial differential equations and Fourier analysis, is studied using perturbation and nonlinear stability methods, and the resulting flow solutions over two types of discrete structures are computed under both stable and unstable conditions. It was found, in particular, that for a subcritical domain with the Reynolds number R slightly less than its critical value Rc, which is defined as the value below which …


A Two-Layered Non-Newtonian Arterial Blood Flow Through An Overlapping Constriction, V. P. Srivastava, Rochana Vishnoi, Shailesh Mishra, Poonam Sinha 2011 Krishna Girls Engineering College

A Two-Layered Non-Newtonian Arterial Blood Flow Through An Overlapping Constriction, V. P. Srivastava, Rochana Vishnoi, Shailesh Mishra, Poonam Sinha

Applications and Applied Mathematics: An International Journal (AAM)

The problem of blood flow through an overlapping constriction in arteries is investigated in this work. To account for the non-Newtonian behavior and the peripheral layer, blood has been represented by a two-fluid model, consisting of a core region of suspension of all the erythrocytes assumed to be a Casson fluid and a peripheral layer of plasma (Newtonian fluid). The expression for the flow characteristics, namely, the impedance, the wall shear stress, the shear stress at the stenosis throats and at the critical height of the stenosis has been derived. Moreover, we present some results concerning the dependence of these …


Digital Commons powered by bepress