InterPore2021

Simulating solute transport through saturated heterogenous medium using triple porosity non equilibrium model

4 Jun 2021, 09:40

1h

Poster (+) Presentation (MS8) Mixing, dispersion and reaction processes across scales in heterogeneous and fractured media Poster +

Speaker

Aman Chandel (Research scholar, School of Engineering, Indian Institute of Technology Mandi, Mandi, India)

Description

This study assumes complex saturated liquid phase volume to be a triple porosity medium consisting of macro, meso and micropore structure. This provides the Triple Porosity Non-Equilibrium (TPNE) model a higher capability of mimicking the physical and chemical non equilibrium present as per the field conditions. The method of finite difference for discretisation is used to solve the model. Semi-analytical solution of Dual Advection Dispersion Equation (DADE) (Leij et al. 2012) validates the model. Different unknown parameters are estimated using parameter estimation algorithm (PEST) and detailed sensitivity analysis is performed to delineate the behaviour of the model against various parameters. The behaviour of the model is studied for the wide range of Peclet number and Damköhler number with the help of temporal moments. The dataset from the experiments conducted on a heterogenous soil column by Huang et al., (1995) is used to calibrate the model and is compared with Mobile Immobile (MIM) model by van Genuchten & Wierenga, (1976b). TPNE emerges as better performer capturing the early breakthrough and skewed breakthrough curves (BTC).

References

Leij, F. J., Toride, N., Field, M. S., & Sciortino, A. (2012). Solute transport in dual-permeability porous media. Water Resources Research, 48(4), 1–13. https://doi.org/10.1029/2011WR011502
Huang, K., Toride, N., & Van Genuchten, M. T. (1995). Experimental investigation of solute transport in large, homogeneous and heterogeneous, saturated soil columns. Transport in Porous Media, 18(3), 283–302. https://doi.org/10.1007/BF00616936
van Genuchten, M. T., & Wierenga, P. J. (1976b). Mass Transfer Studies in Sorbing Porous Media I. Analytical Solutions. Soil Science Society of America Journal, 40(4), 473–480. https://doi.org/10.2136/sssaj1976.03615995004000040011x

Presentation materials

aman_abstract_interpore.docx