Dynamic thermal performance analysis of a molten-salt packed-bed thermal energy storage system using PCM capsules

Ming Wu, Chao Xu and Ya-Ling He

Applied Energy, 2014, vol. 121, issue C, 184-195

Abstract: We investigate the dynamic thermal performance of a molten-salt packed-bed thermal energy storage (TES) system using capsules filled with high-temperature phase change material (PCM), which is identified as a promising low-cost TES system for concentrating solar power (CSP) plants. A transient two-dimensional dispersion-concentric (D-C) model is modified to account for the phase change process within capsules so as to determine the temperature distribution and phase change front within each capsule. Using the model, detailed characteristics of heat transfer between molten salt and the packed PCM capsules are investigated, and a parametric sensitivity analysis is provided. During the discharging process, different variation trends are found for the capsule temperature due to the existence of the isothermal solidification process. As a result, generally there exists a quasi-isothermal region and two thermocline regions for the molten-salt temperature along the tank height, and the molten-salt temperature at the outlet also shows a quasi-isothermal period, during which the molten-salt outlet temperature is very close to the phase change temperature (PCT) of PCM. It is also found that the effective discharging efficiency of the system can be increased by increasing the PCT, decreasing the molten-salt inlet velocity or decreasing the capsule diameter. These results provide suggestions to optimize the design and operational parameters for the system within practical constrains.

Keywords: PCM capsules; Thermal energy storage; Thermocline; Packed-bed; Molten salt (search for similar items in EconPapers)
Date: 2014
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (49)

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0306261914001159
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:appene:v:121:y:2014:i:c:p:184-195

Ordering information: This journal article can be ordered from
http://www.elsevier.com/wps/find/journaldescription.cws_home/405891/bibliographic
http://www.elsevier. ... 405891/bibliographic

DOI: 10.1016/j.apenergy.2014.01.085

Access Statistics for this article

Applied Energy is currently edited by J. Yan

More articles in Applied Energy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().