Moving Boundary Problems are Us

The development and application of numerical methods for transport modelstowards an integrated frame-work for modeling earth surface dynamics from source to sink

Voller, Paola, Mohrig, Parker

Wolinsky, Jerolmack

Kim, Qian, Sittoni

Stefan, Swenson

SA2 Reconstructing delta dynamics from cores and other records

SR2 Determine how physical channel attributes affect nutrient & contaminant dynamics, productivity, and species diversity

Interactions Between Flow and Fan Topography

Some JT Questions: How Does topography influence the flow over fans? Is there fan geometry that crates a bypassing condition ?

Investigate by solving Exner + Shallow Water Eq Over Different Tops.Flat Long

ComboTran.

SA2 Reconstructing delta dynamics from cores and other records

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Normalized enhanced dispersion (DE*)

De

pth

(y

*) λ=0.1

λ=1

λ=5

λ=10

Fitted line

Transport exchange between a stream and its gravel bed is greatly enhanced by surface waves and/or bed forms.

2-D Advection Dispersion

y

CD

yt

CE

A Depth dependent dispersion can Be obtained from problem par.Hence an easy to use meaningful management tool

Can be used to answer questions

What restoration devices can be in place tocreate conditions to increase(dissolved oxygen for fish eggs) or decrease(organic carbon) exchange with the bed.

Further work compare withClark Stream-Lab exp.

SR2 Determine how physical channel attributes affect nutrient & contaminant dynamics, productivity, and species diversity

Through Solution of a transient advection-dispersion can be shown that the laterally averaged concentration penetration CAN Be described by a 1-D Dispersion Equation

y

Increasing Flexibility

GRID---FIN-DIFF

P)y,x(

Efficient solution Ax=b —Difficult to Fit Geometry

MESH---FEM

3

1iiiN)y,x(

Less Efficient solution Ax=b —Easy to Fit GeometryDifficult to adapt

“CLOUD”---SPH

)y,x()y,x(W)y,x( PPP

Even Less Efficient solution Ax=b —Very Easy to Fit Geometry

Easy to adapt

Application of Meshless Methods