Journal
JOURNAL OF HYDROLOGY
Volume 562, Issue -, Pages 385-396Publisher
ELSEVIER SCIENCE BV
DOI: 10.1016/j.jhydrol.2018.05.023
Keywords
Heat tracer test; Thermal dispersion coefficient; Groundwater heat pump (GWHP); Forced groundwater flow; Water injection; Flow velocity
Funding
- National Research Foundation of Korea (NRF) - Korean government (MSIP) [2017R1A2B3002119]
- X-project of the NRF
- Geowater + project in Water Resources Management Program of the MOLIT
- KAIA of Korea
- R&D project on Environmental Management of Geologic CO2 Storage from the KEITI
Ask authors/readers for more resources
Mechanical thermal dispersion has often been neglected or underestimated in the simulation of heat transport in porous media, e.g., by using zero or the default value in simulators, or by using the scaling law for solute dispersivity as a thermal dispersivity value. However, large amounts of water usually injected in groundwater heat pump (GWHP) systems may increase the groundwater flow velocity much faster than natural flow and thus change the importance of mechanical dispersion in heat transport. In this study, to investigate the effects of water injection on the flow field, thermal dispersion coefficient, and associated heat transport process, a laboratory experiment using two different heat sources as tracers was performed at various background flow velocities (Re < 0.52). The analysis results from analytical and numerical models indicate that injected water increases both flow velocities and thermal dispersion coefficients, especially near the injection well, and thus makes the effect of mechanical dispersion on heat transport very important even at low background flow velocity. This result was also found in the field-based modeling results, but the radius of hydraulic and thermal effects was larger. In particular, thermal dispersivity on a field scale is known to increase depending on the scale of measurement and the degree of aquifer heterogeneity. Therefore, to ensure the efficiency and sustainability in field applications such as GWHP systems, it is necessary to evaluate site-specific thermal dispersivity through field experiments.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available