Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Engineering (5)
- Aerospace Engineering (3)
- Aerodynamics and Fluid Mechanics (2)
- Applied Mathematics (1)
- Astrophysics and Astronomy (1)
-
- Chemical Engineering (1)
- Computer Sciences (1)
- Condensed Matter Physics (1)
- Dynamics and Dynamical Systems (1)
- Earth Sciences (1)
- Electrical and Computer Engineering (1)
- Electromagnetics and Photonics (1)
- Engineering Science and Materials (1)
- Geochemistry (1)
- Geology (1)
- Geomorphology (1)
- Life Sciences (1)
- Mathematics (1)
- Medicine and Health Sciences (1)
- Meteorology (1)
- Numerical Analysis and Scientific Computing (1)
- Oceanography and Atmospheric Sciences and Meteorology (1)
- Other Astrophysics and Astronomy (1)
- Other Physics (1)
- Partial Differential Equations (1)
- Propulsion and Power (1)
- Statistical, Nonlinear, and Soft Matter Physics (1)
- Institution
- Publication
- Publication Type
Articles 1 - 10 of 10
Full-Text Articles in Fluid Dynamics
Long-Wave Modeling Of Viscous Film Dynamics Inside A Tube With Time-Dependent Radius, Robert E. Hicks
Long-Wave Modeling Of Viscous Film Dynamics Inside A Tube With Time-Dependent Radius, Robert E. Hicks
Theses and Dissertations
Lung fluid dynamics is a well studied topic and relevant in the field of research surrounding patients with Chronic Obstructive Pulmonary Disease (COPD) and cystic fibrosis. However, the literature on the mathematical description of the net pulmonary fluid transport in the case of constricting and expanding airways is scarce. In this paper we aim to address how breathing contributes to airways clearance in patients with pulmonary diseases such as COPD and CF in which cilia do not function properly. We begin with the flow of a fluid-filled tube with rigid walls of fixed radius and the effects of gravity being …
Analysis Of Titan's Fluvial Features Using Numerical Modeling, Jeshurun Horton
Analysis Of Titan's Fluvial Features Using Numerical Modeling, Jeshurun Horton
Mechanical Engineering Undergraduate Honors Theses
River channels have been observed near the Huygens probe landing site on the surface of Titan, along with evidence of rounded water ice boulders transported through fluid flow. Evidence near the landing site suggests active flow of liquid methane, which has motivated the study of the effects of sediment load and channel sizes on Titan’s fluvial features. A numerical model is used to determine the viscosity, flow velocity, and critical boulder transport diameter based on channel size, slope, and a range of sediment concentrations. This model achieves two ends: first, observed boulder diameters are used to determine the ideal channel …
Superfluid Swimmers, German Kolmakov, Igor S. Aranson
Superfluid Swimmers, German Kolmakov, Igor S. Aranson
Publications and Research
The propulsion of living microorganisms ultimately relies on viscous drag for body-fluid interactions. The self-locomotion in superfluids such as 4He is deemed impossible due to the apparent lack of viscous resistance. Here, we investigate the self-propulsion of a Janus (two-face) light-absorbing particle suspended in superfluid helium 4He (He-II). The particle is energized by the heat flux due to the absorption of light from an external source. We show that a quantum mechanical propulsion force originates due to the transformation of the superfluid to a normal fluid on the heated particle face. The theoretical analysis is supported by the …
Semi-Lagrangian Implicit Bhatnagar-Gross-Krook Collision Model For The Finite-Volume Discrete Boltzmann Method, Leitao Chen, Sauro Succi, Xiaofeng Cai, Laura Schaefer
Semi-Lagrangian Implicit Bhatnagar-Gross-Krook Collision Model For The Finite-Volume Discrete Boltzmann Method, Leitao Chen, Sauro Succi, Xiaofeng Cai, Laura Schaefer
Publications
In order to increase the accuracy of temporal solutions, reduce the computational cost of time marching, and improve the stability associated with collisions for the finite-volume discrete Boltzmann method, an advanced implicit Bhatnagar-Gross-Krook (BGK) collision model using a semi-Lagrangian approach is proposed in this paper. Unlike existing models, in which the implicit BGK collision is resolved either by a temporal extrapolation or by a variable transformation, the proposed model removes the implicitness by tracing the particle distribution functions (PDFs) back in time along their characteristic paths during the collision process. An interpolation scheme is needed to evaluate the PDFs at …
Parameter Identifiability And Estimation In A 1d Cardiovascular Fluid Dynamics Model, Mitchel J. Colebank
Parameter Identifiability And Estimation In A 1d Cardiovascular Fluid Dynamics Model, Mitchel J. Colebank
Biology and Medicine Through Mathematics Conference
No abstract provided.
Investigation Of Endwall Vortex Manipulation In High Lift Turbines Caused By Active Endwall Forcing, Horatio J. Babcock
Investigation Of Endwall Vortex Manipulation In High Lift Turbines Caused By Active Endwall Forcing, Horatio J. Babcock
Theses and Dissertations
With the increased demand for lighter, more fuel efficient and smaller gas turbine engines, the impetus to reduce the weight and size of the turbine has become apparent. One approach to reduce this weight is to reduce the number of blades in the turbine. However, to maintain power output, each blade must be capable of supporting a greater amount of lift. While several high-lift turbine profiles have been detailed in literature, most of these profiles have increased endwall losses, despite their desirable mid-span characteristics. To mitigate this endwall loss, a number of active and passive flow approaches have been studied …
Schlieren Imaging And Flow Analysis On A Cone/Flare Model In The Afrl Mach 6 Ludwieg Tube Facility, David A. Labuda
Schlieren Imaging And Flow Analysis On A Cone/Flare Model In The Afrl Mach 6 Ludwieg Tube Facility, David A. Labuda
Theses and Dissertations
High-speed Schlieren photography was utilized to visualize flow in the Air Force Research Laboratory Mach 6 Ludwieg tube facility. A 7° half-angle cone/flare model with variable nosetip radius and flare angle options was used in the study. Testing was performed at two driver tube pressures, generating freestream Reynolds numbers of 10.0x106 and 19.8x106 per meter. The variable-angle flare portion of the model provided a method for adjusting the intensity of the adverse pressure gradient at the cone/flare junction. As expected from existing literature, boundary layer separation along the cone frustum occurred further upstream as the magnitude of the …
Tracking Shock Movement On The Surface Of An Oscillating, Straked Semispan Delta Wing, Justin A. Pung
Tracking Shock Movement On The Surface Of An Oscillating, Straked Semispan Delta Wing, Justin A. Pung
Theses and Dissertations
A recent research effort, sponsored by the Air Force Office of Scientific Research, numerically investigated the unsteady aerodynamic flow field around an oscillating, straked, delta wing. The study was centered on determining the importance of the unsteady aerodynamic forces acting as a driver for a nonlinear motion known as limit cycle oscillations. The current effort focused on creating a computational model to compare to the results of previous tests and modeling efforts and discover new information regarding the onset of LCO. The computational model was constructed using the Cartesian overset capabilities of the CREATE-AV™ fixed wing fluid dynamics solver Kestrel. …
Hydrodynamic Forces Acting On A Moving Hand, Elizabeth A. Gregorio
Hydrodynamic Forces Acting On A Moving Hand, Elizabeth A. Gregorio
Departmental Honors Projects
The greatest amount of direct propulsion during swimming comes from the force exerted by the hand. It is possible for a swimmer to create a higher effective surface area of the hand by slightly spreading their fingers during the pull phase of the stroke. This phenomenon occurs because of the dynamic forces acting on the hand while it moves through the water. This investigation explores and compares how computational and experimental results suggest the occurrence of this phenomena. This is done first with a simple model of the four fingers (not including the thumb), held with different separations (0.0cm, 0.2cm, …
Computational Model Of One-Dimensional Dielectric Barrier Discharges, Krista G. Marchand
Computational Model Of One-Dimensional Dielectric Barrier Discharges, Krista G. Marchand
Theses and Dissertations
As theory lags experiment for dielectric barrier discharge flow control, two different computational methods are implemented to give further insight into characteristics of the dielectric barrier discharge (DBD). A one-dimensional fluid model of a surface-type dielectric barrier discharge is created using He as the background gas. This simple model, which only considers ionizing collisions and recombination in the electropositive gas, creates an important framework for future studies into the origin of experimentally observed flow-control effects of the DBD. The two methods employed in this study include the semi-implicit sequential algorithm and the fully implicit simultaneous algorithm. The first involves consecutive …