EXPERIMENTAL STUDY ON EFFECT OF STRATIFIED DISCHARGE ON THERMAL STRATIFICATION IN LARGE-PIT THERMAL ENERGY STORAGE

Jia Shangdong; Chen Yaowen; Wang Dengjia; Gao Meng; Liu Yanfeng; Fan Siqin

doi:10.19912/j.0254-0096.tynxb.2023-1890

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Acta Energiae Solaris Sinica ›› 2025, Vol. 46 ›› Issue (3) : 470-478. DOI: 10.19912/j.0254-0096.tynxb.2023-1890

EXPERIMENTAL STUDY ON EFFECT OF STRATIFIED DISCHARGE ON THERMAL STRATIFICATION IN LARGE-PIT THERMAL ENERGY STORAGE

Jia Shangdong¹, Chen Yaowen^1,2, Wang Dengjia^1,2, Gao Meng³, Liu Yanfeng^1,2, Fan Siqin¹

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Abstract

In this paper, a scale model experimental platform was built to research the effect of the stratified discharge on the thermal stratification by combining the evaluation methods of outlet temperature, N_mix number, and Ri number. The results show that the closer the outlet is to the top of the thermal storage tank, the more obvious the decreasing trend of the water temperature and outlet temperature is, the thinner the thermocline is, and the N_mix number increases faster, indicating that the degree of thermal stratification of the water body decreases. The Ri number is mostly determined by volume flow rates, and the position of the outlets has little bearing on it. The discharge efficiency increases with time when the outlet is located above the middle line of the pool volume. With fixed outlet positions, as flow rate increases, the water temperature, N_mix number, and discharge efficiency vary faster, and the closer the outlet is to the top, the more the volume flow rates affect the thermal stratification of the water body. The change in volume flow rates affects thermal stratification more than the change in outlet height.

Key words

solar energy / heat storage / thermal stratification / discharge / PTES / scale model experiment

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Jia Shangdong, Chen Yaowen, Wang Dengjia, Gao Meng, Liu Yanfeng, Fan Siqin. EXPERIMENTAL STUDY ON EFFECT OF STRATIFIED DISCHARGE ON THERMAL STRATIFICATION IN LARGE-PIT THERMAL ENERGY STORAGE[J]. Acta Energiae Solaris Sinica. 2025, 46(3): 470-478 https://doi.org/10.19912/j.0254-0096.tynxb.2023-1890

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