SciDAC Projects: Groundwater

Tim Scheibe

PNNL-SA-52370

Science Application

• Hybrid Numerical Methods for Multiscale Simulations of Subsurface Biogeochemical Processes– Tim Scheibe (PNNL) – Principal

Investigator• Alexandre Tartakovsky, Bruce Palmer,

Karen Schuhardt (PNNL)• Paul Meakin, George Redden (INL)• Daniel Tartakovsky (UC San Diego)• Scott Brooks (ORNL)

Motivation

• “Scientifically rigorous models of subsurface reactive transport that accurately simulate contaminant mobility across multiple length scales remain elusive.”

• Reason: Disparity in scale between PROCESS and PHENOMENON

Two critical classes of problems:

• Problems with strong media heterogeneity at multiple scales

• Problems with strong coupling between flow, transport, and reaction processes

Na2CO3 CaCl2

Steady state solubility product <CA><CB>. Non-reactive flow, Pe=2.8

t = 1000

t = 3000t = 1000

Changes in solubility product <CA><CB> as result of precipitation. Reactive flow, Pe=2.8

t = 6000

Proposed Approach

• Hybrid Multiscale Modeling– Directly couple models with different process

representations at fundamental scales– Adaptively control which processes / models

are applied in which parts of the model domain

Examples of Multiscale Models

Zoom

Multiscale Systems Engineering Research Center (MSERC),Rensselaer Polytechnic Institute, Dr. Jacob Fish, PI

SciDAC Technologies and

Collaborations• Science Application Partnerships (SAPs):

– Component Software Infrastructure for Achieving High Level Scalability in Groundwater Reactive Transport Modeling and Simulation (Palmer)

– Process Integration, Data Management, and Visualization for Subsurface Simulations (Schuchardt)

• Visualization tools (multiscale) – VACET• High-performance solvers – TOPS• Advanced gridding technologies - ITAPS