- 1Seoul National University, School of Earth and Environmental Sciences, Seoul, Korea, Republic of (bjy14114@snu.ac.kr)
- 2Korea Atomic Energy Research Institute, Daejeon, Republic of Korea (bh-park@kaeri.re.kr)
- 3The University of Newcastle, School of Environmental and Life Sciences, Newcastle, Australia (gabriel.rau@newcastle.edu.au)
The Darcy-scale approach effectively aggregates pore-scale behaviors for hydrogeological applications. However, understanding the influence of pore-scale heterogeneity on the estimation of Darcy-scale quantities (e.g. Darcy flux, dispersion coefficients) remains limited. To address this, the solute and heat tracer experiments were conducted using three different sands with distinct particle size distributions (d50 = 0.52, 0.76, 0.84 mm; U = 1.41, 1.50, 2.02). Tracer front velocities and dispersion coefficients of solute and heat were analyzed by applying analytical models. Observed electrical conductivity and temperature time series demonstrated good agreement with analytical solutions (R2 > 0.9), thereby confirming the validity of the chosen solutions. As the results of examining the tracer front velocity estimates, However, Darcy flux was significantly underestimated in both solute and heat. The underestimation of velocities was more pronounced in smaller particle sizes and wider particle size distributions due to pore-scale heterogeneity arising from the complexity of the pore network. Unlike velocities, normalized dispersion coefficients along with the Peclet number exhibited a larger dispersion for the increase of pore network complexity. Consequently, our findings emphasize considering the potential uncertainty caused by pore-scale heterogeneity on Darcy-scale quantities.
Keywords: Pore-scale heterogeneity; Tracer front velocity; Thermal dispersion; Solute dispersion; Lab-scale experiment
Acknowledgements
This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) (No. 2022R1A2C1006696). This work was also supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government(MSIT) (No. 2022R1A5A1085103). This work was also supported by the Nuclear Research and Development Program of the National Research Foundation of Korea (NRF-2021M2E1A1085200).
How to cite: Baek, J., Park, B.-H., Rau, G., and Lee, K.-K.: Influence of Pore-Scale Heterogeneity on Darcy-Scale Heat and Solute Transport, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-6288, https://doi.org/10.5194/egusphere-egu25-6288, 2025.
