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Evan Lemley Engineering and Physics Department Research Roundtable Dec. 5, 2008. Fluid Dynamics Research. Fluids. Infinitely stretchable Liquids and Gases Properties density viscosity ( ) surface tension thermal conductivity diffusivity. Laminar Flow. ℜ D < 2000 – Laminar
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Evan Lemley Engineering and Physics Department Research Roundtable Dec. 5, 2008 Fluid Dynamics Research
Fluids • Infinitely stretchable • Liquids and Gases • Properties • density • viscosity () • surface tension • thermal • conductivity • diffusivity
Laminar Flow ℜD < 2000 – Laminar 2100 < ℜD < 5000 Transition ℜD > 5000 – Turbulent From CFD Simulations by Handy & Lemley
Laminar Flow • Flow follows streamlines that do not change with time • Analytical solutions possible for simple geometries for some cases • Flow in pipes, around airfoils, etc..., not usually laminar.
Turbulent Flow • Turbulent Flow -- Flow is sinuous/random fluctuations • Very few analytical solutions • Turbulence dominates flow problems at large scale
Micro-Fluidics Microfluidic Valve Structure. (http://www.cchem.berkeley.edu/sjmgrp/people/boris/boris.htm) Highly porous magnesian limestone. (www.dawntnicholson.org.uk) Laminar Flow dominates at micro-scale
Porous Network Simulator - FTPM (Collaboration with Univ. of Oklahoma) • 3D Monte Carlo networks from normal, beta, or empirical distribution (pore size pdf) • Coordination Number (1, 2, 3) number of pores entering and leaving a junction • ± 90˚ Projection on the xy plane of a 3D network that has 200 entry points at x=0, porosity equal to 10% and a range of ±60˚ relative to the x axis and ±30˚ relative to the y axis.
Flow Network Analysis Design and Analysis of networks depends on knowledge of flow and energy losses in arbitrary branches. No systematic studies to generalize these bifurcations ACS – PRF Grant to Simulate and perform Experiments for Laminar Flow in Bifurcations
OU Dimitrios Papavassiliou, Chem. Engr. Henry Neeman, Supercomputing Center Research Team • UCO – Current UG's • Tim Handy - Simulation • Willy Duffle • Jesse Haubrich • UCO – Past UG's Matt Mounce, Josh Brown, Scott Murphy, Jon Blackburn, Jamie Weber, Sudarshan Rai Students have been funded by ORG, ACS-PRF grant, and satisfying course requirements
Computational Fluid Dynamics f2 = 0.1, θ2=45°, θ3=45°, d2/d1=0.5, d3/d1=1.5. f2 = 0.1, θ2=45°, θ3=45°, d2/d1=0.5, d3/d1=1.5. Lemley, E.C., Papavassiliou, D.V., and H.J. Neeman, 2007, “Simulations To Determine Laminar Loss Coefficients In Arbitrary Planar Dividing Flow Geometries,” Proceedings of FEDSM2007, 5th Joint ASME/JSME Fluids Engineering Conference, paper FEDSM2007-37268. Handy, T.A., Lemley, E.C., Papavassiliou, D.V., and H.J. Neeman, 2008, “Simulations to Determine Laminar Loss Coefficients for Flow in Circular Ducts with Arbitrary Planar Bifurcation Geometries ,” Proceedings of FEDSM2008, ASME Summer Fluids Engineering Conference, paper FEDSM2008-55181.
Initially Laminar Flow Around Sphere Trip Wire on front of sphere reduces drap by tripping turbulent boundary layer. Efluids Image Gallery: http://www.efluids.com