Characterization of mixing and spreading in a bounded stratified media
Vanessa Zavala, Marco Dentz, Xavier Sánchez-Vila 13 marzo 2008
Contents
Objective. Basics.
Model. StochasticFramework. Transport coefficients.
Transport Coefficients in a bounded stratified medium.
Motivation. Results
Conclusions.
Objective
Point injection at y=0 50
l
25
2a
y
0
-25Investigate solute mixing and spreading in a vertically bounded random medium in terms of effective dispersion coefficients.
0 50 x
Uniform line injection 50
-50 -50
100
150
25
Weinvestigate two initial conditions: 1) Point like injection. 2) Uniform line injection.
0
y
-25
-50 -40
-20
0
20
40 x
60
80
100
120
Basics
•Advection dispersionequation. Homogeneous case:
Center of mass position
flow •Center of mass position:
•Boundary conditions: •Solution:
Instantaneous injection at t=0.
width
•Width:
Basics
Model.Point injection at y=0 50 25
Center of mass position
•We have a constant gradient: Je1. •Incompressibility condition •Exact Solution:
0
y
-25
e2
-50 -50
flow
0
width
50 x100 150
e1
?
Basics.
Stochastic Framework
We do not know the heterogeneity deterministically !!
Basics
Solution of the transport differential equation:
Solve it in terms of knownparameters:
Axial Moment Equations:
•Diffusion equation. Onedimensional projection of the advection dispersion equation.
Transport Coefficients
Point like injection
•Dentz and Carrera(2007): Defined effective dispersion coefficients for a single realization in terms of local moments.
Single realization
Ensemble
Uniform line injection
Transport Coefficients
Singlerealization
Ensemble
Transport Coefficients
Bounded stratified media
Why are we interested in stratified media models?
Effective and Ensemble Dispersion Coefficients
1000
100 DEFF DENS 10...
Regístrate para leer el documento completo.