Energy and exergy analysis of an experimentally examined latent heat thermal energy storage system

M. Rahimi, S. Saedi Ardahaie, M.J. Hosseini and M. Gorzin

Renewable Energy, 2020, vol. 147, issue P1, 1845-1860

Abstract: In this study, an experimental investigation is carried out on a Latent Heat Thermal Energy Storage system (LHTES). All the experimental data are optimized using thermodynamic principles in which exergy analysis is conducted to examine the system’s performance at different time constants. The proposed system uses paraffin wax RT35 as Phase Change Material (PCM) and water as Heat Transfer Fluid (HTF). The water enters the successive helical rounds of the tube and the melting process initiates from locations around the tube and propagates throughout the shell. In recent years, surface enhancement through using spiral and helical configurations of the tube is preferred by scientists to overcome the problem of slow charging in the outermost positions of the subdomain filled with PCM. Hence, the effect of the change in the coil number of the heat exchanger is investigated by choosing three different helical coil diameters which are 50, 70 and 90 mm, respectively. It is aimed to find the most efficient case capable of storing the maximum energy possible as well as higher exergy efficiencies in minimum melting duration through the phase change process. Parameters such as the transferred heat from HTF to PCM, PCM average temperature, melting front growth, Nusselt number, exergy efficiency, and the entropy generation number are investigated meticulously. Results showed that for the highest used helical diameter (90 mm) compared to the lowest one (50 mm), better melting performance is observed in which the melting time is reduced by 72.6%. Moreover, although some cases may achieve higher exergy efficiencies at their full melting time, they are not offered as best choices due to the limitations in heat storage time duration.

Keywords: Helical tube; Latent heat; Sensible heat; Phase change material; Entropy generation number; Coil diameter; Exergy efficiency (search for similar items in EconPapers)
Date: 2020
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (11)

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0960148119314636
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:renene:v:147:y:2020:i:p1:p:1845-1860

DOI: 10.1016/j.renene.2019.09.121

Access Statistics for this article

Renewable Energy is currently edited by Soteris A. Kalogirou and Paul Christodoulides

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