Elektrane (2025) [pp. 144-157]
AUTHOR(S) / АУТОР(И): Dejan Cvetinović, Nikola Ćetenović, Marko Milić, Dejan Vladičić
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DOI: https://doi.org/10.46793/EEP25.144C
ABSTRACT / САЖЕТАК:
This paper presents a numerical calculations with purpose to optimize a Thermal Energy Storage (TES) system, which can be used to store thermal energy and for maintaining energy balance between producers and consumers. This system can reduce electrical consumption by acting like a thermal battery. The producers are chillers that cool water to 5 °C, which is then used for cooling installations categorized as consumers. After utilizing the chilled water, the consumers return it to the reservoir at an elevated temperature of 13 °C. The warmed water is subsequently returned to the chiller, where the cooling process is repeated. A key challenge is achieving thermal stratification within the reservoir, with cold water at the bottom and warm water at the top, ensuring a thin thermocline layer while minimizing mixing between layers. The system operates as a flow-through thermodynamic process, where the fluid circulates between chiller and consumer. To maintain stratification, the Reynolds and Froude numbers are controlled within appropriate limits. The design of pipelines and diffusers, especially nozzles, is optimized to minimize turbulence and preserve thermal gradients. Numerical simulations using Ansys Fluent were performed to model various operational regimes and predict thermocline behavior. The results demonstrate that the TES system successfully maintains thermal stratification, with the main difference across regimes being the integral time required to reach the desired parameters. The paper concludes that the TES system’s design is effective for thermal storage and energy efficiency. A physical prototype will be constructed which will enable a comparative analysis between experimental and simulated data.
KEYWORDS / КЉУЧНЕ РЕЧИ:
Thermal Energy Storage (TES), thermocline, transient analysis, CFD optimization
ACKNOWLEDGEMENT / ПРОЈЕКАТ:
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