Numerical Tracer Experience The MNI2 Project Development and utilization of simulation tools for chemical engineering The goals 1. Implement and simulate a numerical tracer test through a porous media 2. Analyze the Residence Time Distribution (RTD) through a porous media Specific goals 1. Implement and simulate a numerical tracer test through a sand column a) Implement and simulate the water flow process by solving Richards equation b) Check the mass balance equation for water flow process c) Display and comment the hydrodynamic functions at different times until T = 1 day d) At which time TS the column reached the steady state conditions ? e) Implement and simulate the convection-dispersion equation by considering steady state conditions for water flow process and introducing a tracer as a conservative substance during TSf) Display and comment the outlet concentration of the tracer Specific goals 1. Implement and simulate a numerical tracer test through a sand column 2. Analyze the Residence Time Distribution (RTD) through the porous media a) Check the mass balance equation for convection-dispersion process b) Calculate and comment the RTD parameters for different Neumann conditions: q0, 2q0, 3q0. Governing equation for water flow process through variably saturated porous media Water input Filter Sand column L
c m z = 0 cm z = -L cm z ℎ ℎ = ℎ ℎ − 1
ℎ , = 0 = ℎ = 0, = = −, = ℎ = −, q0 = −0.0001 h0 = −1000 Ksat = 0.0363 cm/s α = 0.0472 cm-1 n = 1.48 θsat = 0.43 θres = 0.08 Governing equation for convection dispersion process through variably saturated porous media ∙ + ∙ − =0 , = 0 = 0 = 0, < ≤ = = 0, < #$% > = 0 = − = 0 θ and q are respectively volumetric water content and Darcian flux from water flow process C0 = 1 '/ D = 0.004 cm2/s t1 = 600s
