Dr. Marc Madou, UCI, Winter 2015 Class IV Transport in
Electrochemistry (II) Electrochemistry MAE-212
Slide 2
Table of Content Reynolds Numbers Low Reynolds Numbers OHP,
Diffusion Layer Thickness, Hydrodynamic Boundary Layer Thickness
Mixing in low Reynolds number fluids to enhance electrochemical
reactions
Slide 3
Reynolds Numbers The dimensionless Reynolds number is given by:
where v is the mean velocity of an object relative to the fluid (SI
units: m/s), L is a characteristic linear dimension (SI: m), is the
dynamic viscosity of the fluid [SI: Pas or Ns/m or kg/(ms)] and is
the kinematic viscosity ( : / ) (m/s) and is the density of the
fluid (SI: kg/m) Note that multiplying the Reynolds number by
yields: which is the ratio of: Or also:
Slide 4
Small systems are less turbulent than large ones (e.g., flow in
very thin pipes is laminar). Slow flows are laminar, while fast
flows are turbulent. More viscous materials are less turbulent
(e.g., oil in a pipeline is less turbulent than water in the same
pipeline). Reynolds Numbers
Slide 5
Low Reynolds Numbers Creeping flow also known as Stokes Flow or
Low Reynolds number flow Occurs when Re
