Skip to main content
ARS Home » Research » Publications at this Location » Publication #135920

Title: Adaptive grid refinement in numerical models for water flow and solute transport in soils: A review

Author
item MANSELL, ROBERT - UNIVERSITY OF FLORIDA
item Ma, Liwang
item Ahuja, Lajpat
item BLOOM, STEPHEN - UNIVERSITY OF FLORIDA

Submitted to: Vadose Zone Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/15/2002
Publication Date: 3/30/2002
Citation: Mansell, R.S., Ma, L., Ahuja, L.R., Bloom, S.A. 2002. Adaptive grid refinement in numerical models for water flow and solute transport in soils: A review. Vadose Zone Journal. 1:222-238.

Interpretive Summary: Insufficient spatial/temporal resolution is a common source of errors in numerical solutions of both water flow and solute transport in the variably-unsaturated vadose zone. Evaporation near the surface, as well as infiltration into initially dry soil profiles, typically create mobile local regions with large gradients of water head. Convection-dominant transport of solutes during water flow in soil also tends to create steep moving fronts of concentration with large localized concentration gradients. Groundwater flow and solute transport in highly heterogeneous aquifers also tends to be preferentially channeled through regions of high flow rates. Incorporation of local adaptive grid refinement (LAGR) algorithms in numerical models have been used to enhance the accuracy of numerical approximations by automated adjustment of local spatial resolution for such cases. Advantages and limitations for using LAGR algorithms in finite-difference and finite element numerical models for flow/transport in soils are examined.

Technical Abstract: Insufficient spatial/temporal resolution is a common source of errors in numerical solutions of both water flow and solute transport in the variably-unsaturated vadose zone. Evaporation near the surface, as well as infiltration into initially dry soil profiles, typically create mobile local regions with large gradients of water head. Convection-dominant transport of solutes during water flow in soil also tends to create steep moving fronts of concentration with large localized concentration gradients. Groundwater flow and solute transport in highly heterogeneous aquifers also tends to be preferentially channeled through regions of high flow rates. Incorporation of local adaptive grid refinement (LAGR) algorithms in numerical models have been used to enhance the accuracy of numerical approximations by automated adjustment of local spatial resolution for such cases. Advantages and limitations for using LAGR algorithms in finite-difference and finite element numerical models for flow/transport in soils are examined.