1. This presentation discusses the use of computational fluid dynamics and mathematical modeling to optimize groundwater remediation. We use simplified two dimensional models first and Fluent (a well-know fluid flow simulator) to later obtain three-dimensional flow through an aquifer with varying contamination profiles and pumping strategies. Groundwater Remediation * University of Oklahoma – Chemical Engineering Taren Blue, Laura Place, ** Miguel Bagajewicz * This work was done as part of the capstone Chemical Engineering class at the University of Oklahoma ** Capstone Undergraduate students ** Capstone Undergraduate students 1.Analytical model 2.Euler approximation 3.Initial fluid flow model 4.Refined fluid flow model Analysis Methods Abstract Drawing Geometry - Gambit Aquifer Characteristics Porosity of 25% Porosity of 25% Dimensions: 40×10×20 Dimensions: 40×10×20 Unit length in meters Unit length in meters Volume = 8000 m 3 Volume = 8000 m 3 Desired Concentration = 3×10 -7 kg/L Desired Concentration = 3×10 -7 kg/L Basis - Newalla OK site Basis - Newalla OK site Nonuniform Concentration Profiles Plume Profile 1 Plume Profile 2 Plume Profile 3 Fluid Flow Simulation Fluid flow simulations were run in Fluent, a computational fluid dynamics software, and flow profiles were used to find concentration profiles. Initial Trials: Contamination plume was assumed to have uniform initial concentration Contamination plume was assumed to have uniform initial concentration Well location constant Well location constant Wells pump in through side of aquifer Wells pump in through side of aquifer Secondary trials: Nonuniform initial concentration profiles Nonuniform initial concentration profiles Pumping locations varied with time Pumping locations varied with time More realistic well placement- wells enter through top of aquifer. More realistic well placement- wells enter through top of aquifer. Advantage of Simulation Method Many current models only involve two-dimensional analysis of the contamination profile. Fluid flow simulations allow for three dimensional modeling using 3D flow patterns of water in porous media. Imaginary Planes Acknowledgements Linden Heflin Peter Lohateeraparp Roman Voronov Imaginary planes are drawn and named individually in Fluent in order to find the mass flux through the planes. Initial Fluid Flow Analysis The geometries used are shown. Examples of path lines are displayed for two different well configurations. The path lines are colored by velocity. Blue faces represent inlets. Red faces represent outlets. A “generic” geometry is drawn in Gambit and imported into Fluent. Faces at the bottom of the pipes are turned “on” and “off” by being designated a mass flow inlet, outflow, or wall. Pumping Strategies – Changing Well Configuration with Time Strategy for Plume Profile 1 Jeffrey Harwell Benjamin Shiau Rufei Lu Strategy for Plume Profile 2 Strategy for Plume Profile 3 Blue faces represent mass flow inlets. Red faces represent outflows. White faces are “off.” Flow Profiles – Path Lines Colored by Velocity Step 1 Step 2 Step 3 Step 1 Step 2 Step 3 Step 1 Step 2 Step 3 Plume 1 Step 1 Plume 1 Step 2 Plume 1 Step 3 Plume 2 Step 1 Plume 2 Step 2 Plume 2 Step 3 Plume 3 Step 1 Plume 3 Step 2 Plume 3 Step 3 Concentration Changes Over Time Conclusions t = 4 dayst = 20 dayst = 50 dayst = 4 dayst = 20 dayst = 50 dayst = 4 dayst = 20 dayst = 50 days Velocity Contours Plume 3 Step 2 Plume 3 Step 3 Computational fluid dynamics can be applied to simulate flow of liquid through a porous media for modeling the remediation of a contamination plume. Computational fluid dynamics can be applied to simulate flow of liquid through a porous media for modeling the remediation of a contamination plume. This model builds upon previous 2D modeling schemes by analyzing fluid flow in three dimensions. This model builds upon previous 2D modeling schemes by analyzing fluid flow in three dimensions. Imaginary planes allow for accurate tracing of flow profiles. Imaginary planes allow for accurate tracing of flow profiles. This method can be used in the analysis of various contamination plumes with: This method can be used in the analysis of various contamination plumes with: Varying initial concentration Varying initial concentration Varying shape Varying shape Model allows for varying pumping position and pumping rate with time. This can cause more effective cleaning and could lead to lower energy costs. Model allows for varying pumping position and pumping rate with time. This can cause more effective cleaning and could lead to lower energy costs.