AUTOR(I) / AUTHOR(S): Mahir Hafizović, Muhamed Hadžiabdić, Bojan Ničeno
DOI: 10.46793/EEE25-1.24H
SAŽETAK / ABSTRACT:
This study presents a numerical analysis of heat transfer phenomena within an underground thermal energy storage system using Computational Fluid Dynamics (CFD). Three scenarios were analysed to examine heat transfer mechanisms: (i) Influx of hot water – Hot water enters the chamber, displacing colder water and transferring heat to both the surrounding soil and the outgoing water. The soil, acting as a thermal reservoir, absorbs heat with minimal temperature variation, except in regions near the chamber; (ii) Natural cooling – With the chamber’s inlets and outlets sealed, the water gradually cools through interaction with the colder surrounding soil. The focus is on the initial cooling rate, which determines how long the water remains above a certain temperature before reaching thermal equilibrium; (iii) Heat extraction via a heat exchanger – A submerged heat exchanger extracts heat from the chamber water while the surrounding soil compensates for the loss. The efficiency of this process depends on the dimensions and operational parameters of the heat exchanger.
The results indicate that in all scenarios, the system maintains stable thermal stratification, with warmer water staying in the upper layers while cooler water settles due to density differences. The interaction between water and soil plays a crucial role – acting as a heat source during extraction and as a reservoir during cooling.
KLJUČNE REČI / KEYWORDS:
thermal energy storage, heat transfer, geothermal energy, solid-fluid interaction, aquifer, computational fluid Dynamics (CFD)
LITERATURA / REFERENCES:
- Kim, .J, Lee, Y., Yoon, W.S., Jeon, J.S., Koo, M.H., Keehm, Numerical modeling of aquifer thermal energy storage system, Energy, Vol. 35, No. 12, pp. 4955-4965, 2010. https://doi.org/10.1016/j.energy.2010.08.029
- Sommer, W.T., Doornenbal, P.J., Drijver, B.C., Van Gaans, P.F.M., Leusbrock, I., Grotenhuis, J.T.C., Rijnaarts, H.H. Thermal performance and heat transport in aquifer thermal energy storage, Hydrogeology Journal, Vol. 22, No. 1. pp. 263-279, 2014. http://doi.org/10.1007/s10040-013-1066-0
- Major, M., Poulsen, S.E., Balling, A numerical investigation of combined heat storage and extraction in deep geothermal reservoirs, Geothermal Energy, Vol. 6, No. 1, pp. 1–16, 2018. https://doi.org/10.1186/s40517-018-0089-0
- Schmidt, T., Pauschinger, T., Sørensen, P.A., Snijders, A., Djebbar, R., Boulter, R., Thornton, Design aspects for large-scale pit and aquifer thermal energy storage for district heating and cooling, Energy Proc, Vol. 149, pp. 585-594, 2018.https://doi.org/10.1016/j.egypro.2018.08.223
- Wesselink, M., Liu, W., Koornneef, J., Van Den Broek, Conceptual market potential framework of high temperature aquifer thermal energy storage – A case study in The Netherlands, Energy, Vol. 147, pp. 477-489, 2018. https://doi.org/10.1016/j.energy.2018.01.072
- Lee, K. A review on concepts, applications, and models of aquifer thermal energy storage systems, Energies, Vol. 3, No. 6, pp. 320-334, 2010. https://doi.org/10.3390/en3061320
- Kong, L., Zhu, N. CFD simulations of thermal stratification heat storage water tank with an inside cylinder with openings, Procedia Engineering, Vol. 146, pp. 394-399, 2016. https://doi.org/10.1016/j.proeng.2016.06.419
- Feng, H., Li, H., He, S., Qi, J., Han, K., Gao, M. Numerical simulation on thermal stratification performance in thermocline water storage tank with multi-stage middle perforated obstacles, Thermal Science and Engineering Progress, Vol. 35, 101473, 2022. https://doi.org/10.1016/j.tsep.2022.101473
- Yaïci, W., Ghorab, M., Entchev, E., Hayden, S. Three-dimensional unsteady CFD simulations of a thermal storage tank performance for optimum design, Applied Thermal Engineering, Vol. 60, No. 1-2, pp. 152-163, 2013. https://doi.org/10.1016/j.applthermaleng.2013.07.001
- Gao, L., Lu, H., Sun, B., Che, D., Dong, L. Numerical and experimental investigation on thermal stratification characteristics affected by the baffle plate in thermal storage tank, Journal of Energy Storage, Vol. 34, 102117, 2021. https://doi.org/10.1016/j.est.2020.102117
- Hanjalic, K., Popovac, M., Hadziabdic, M. A robust near-wall elliptic-relaxation eddy-viscosity turbulence model for CFD, International Journal of Heat and Fluid Flow, Vol. 25, pp. 1047-1051, 2004. https://doi.org/10.1016/j.ijheatfluidflow.2004.07.005
- Hadziabdic, M., Hafizovic, M., Niceno, B., Hanjalic, K. A rational hybrid RANS-LES model for CFD predictions of microclimate and environmental quality in real urban structures, Building and Environment, 217, 109042, 2022. https://doi.org/10.1016/j.buildenv.2022.109042
- Hadziabdic, M., Hodza, A., Niceno, B. Modelling urban canopy with object-based porosity model, International Journal of Heat and Fluid Flow, 107, 109394, 2024. https://doi.org/10.1016/j.ijheatfluidflow.2024.109394
- Hadziabdic, M., Niceno, B. Reconstruction of Nusselt number in RANS computations with wall function approach, Nuclear Engineering and Design, 412, 112461, 2023. https://doi.org/10.1016/j.nucengdes.2023.112461
- Hadziabdic, M. LES, RANS and Combined Simulation of Impinging Flows and Heat Transfer, PhD thesis, Delft University of Technology, Delft, The Netherlands, 2006. https://resolver.tudelft.nl/uuid:47cb00a2-d935-4a0a-b68b-a0440cfb9d26 [pristupljeno 24.03.2025]
- Hanjalić, K., Laurence, D., Popovac, M., Uribe, J. 𝜐2∕𝑘 − 𝑓 Turbulence model and its application to forced and natural convection. In: Rodi, W., Mulas, M. (Eds.), Engineering Turbulence Modelling and Experiments, Vol. 6, pp. 67-76, 2005. https://doi.org/10.1016/b978-008044544-1/50005-4
- Delibra, G., Hanjalic, K., Borello, D., Rispoli, F. Vortex structures and heat transfer in a wall bounded pin matrix: LES with a RANS wall treatment, International Journal of Heat and Fluid Flow, Vol. 31, No. 5, 740-753, 2010. https://doi.org/10.1016/j.ijheatfluidflow.2010.03.004
- Wieringa, J. Updating the Davenport roughness classification, Journal of Wind Engineering and Industrial Aerodynamics, Vol. 41, No. 1-3, pp. 357-368, 1992.https://doi.org/10.1016/0167-6105(92)90434-C
- Niceno, B. An Unstructured Parallel Algorithm for Large Eddy and Conjugate Heat Transfer Simulations, PhD thesis, Delft University of Technology, Delft, the Netherlands, 2001. https://scispace.com/pdf/an-unstructured-parallel-algorithm-for-large-eddy- and-3utpih4hqz.pdf [pristupljeno 23.03.2025]
- Niceno, B., Hanjalic, K. Unstructured large-eddy and conjugate heat transfer simulations of wall-bounded flows, in: S. Sunden, M. Faghri (Eds.), Modelling and Simulation of Turbulent Heat Transfer, WIT Press, USA, pp. 35-76, 2005.
- Borello, D., Salvagni, A., Hanjalic, K. Effects of rotation on flow in an asymmetric rib-roughened duct: LES study, International Journal of Heat and Fluid Flow, Vol. 55, pp. 104-119, 2015. https://doi.org/10.1016/j.ijheatfluidflow.2015.07.012
- Palkin, E., Hadziabdic, M., Mullyadzhanov, R., Hanjalic, K. Control of flow around a cylinder by rotary oscillations at a high subcritical Reynolds number, Journal of Fluid Mechanics, Vol. 855, pp. 236-266, 2018. https://doi.org/10.1017/jfm.2018.639
- Van Reeuwijk, M., Hadziabdic, M. Modelling high Schmidt number turbulent mass transfer, International Journal of Heat and Fluid Flow, Vol. 51, pp. 42-49, 2015. https://doi.org/10.1016/j.ijheatfluidflow.2014.10.025
- Temmerman, L., Hadziabdic, M., Leschziner, M.A., Hanjalic, K. A hybrid two-layer URANS–LES approach for large eddy simulation at high Reynolds numbers, International Journal of Heat and Fluid Flow, Vol. 26, No. 2, pp. 173-190, 2005. https://doi.org/10.1016/j.ijheatfluidflow.2004.07.006
- Hafizovic, M., Hadziabdic, M., Niceno, B. Simulation of pollutant dispersion in a real urban configuration under strong stratification, in 10th International Symposium on Turbulence, Heat and Mass Transfer, THMT-23, Rome, Italy, pp. 12, 11-15 September 2023. http://dx.doi.org/10.1615/ICHMT.THMT-23.820