Download - Modeling the Internal Flow of a Droplet
Modeling the Internal Flow of a Droplet
Craig Ferguson
Table of Contents
• Problem Definition• Applications• Physical Background
• Program Design
• Algorithm Used
• User Interface
• Current Progress
• Future Work
Electrowetting
[1]
Electrowetting Applications
[2] [3]
Problem Definition
Model the flow inside a droplet moving between two infinite plates
Actual Situation (Droplet)
Current Model (Pipe Flow)
Physical Background
• Navier Stokes Equations [4]
• Computational Fluid Dynamics
Program Design
Inputs – Wall Velocities, Droplet Shape, Viscosity, Density, Droplet Size
Algorithm – Variation on SIMPLE
Outputs – Graphical Representations of Fluid Flows and Pressures: Vector Plots, Topographical Plots
Considered Algorithm
SIMPLE – Semi-Implicit Method for Pressure-Linked Equations
1. Guess P
2. Calculate (u, v) for surrounding nodes
3. Correct the guessed pressures and velocities
4. Repeat until convergence
Coordinate Transformations
Program Design
Results
Results
Results
Future Work
• Finish coordinate transformations
• Set up boundary conditions for desired problem
• Obtain results
• Test results against laboratory data, to be gathered
• Modify program to be more general or more efficient
References
[1] Duke University. (June 2004). “Digital Microfluidics by Electrowetting, Duke University.” http://www.ee.duke.edu/research/microfluidics/.
[2] http://www.answers.com/topic/e-ink-flex-tablet-display-jpg
[3] Liquavista http://www.liquavista.com/files/LQV060828XYR-15.pdf
[4] Weisstein, Eric. (2005) “Navier-Stokes Equations – From Eric Weisstein’s World of Physics.” http://scienceworld.wolfram.com/physics/Navier-StokesEquations.html.
Questions? Comments?