Energy storage in latent heat storage of a solar thermal system using a novel flat spiral tube heat exchanger. (August 2019)

• Record Type: Journal Article
• Authors: Ardahaie, S. Saedi; Hosseini, M.J.; Ranjbar, A.A.; Rahimi, M.
• Is Part Of: Applied thermal engineering. Volume 159(2019)
• Publication Date: 2019-08
• Subjects: PCM charging -- Flat spiral tube heat exchanger -- Solar -- Irregular distribution of flat spiral tube planes -- Tilt angle; Heat engineering -- Periodicals; Heating -- Equipment and supplies -- Periodicals; Periodicals; 621.40205
• DOI: 10.1016/j.applthermaleng.2019.113900
• Languages: English
• ISSNs: 1359-4311

Abstract

Graphical abstract: Highlights: Energy storage in a novel latent heat storage system is investigated numerically. The proposed system is studied under various geometrical and boundary conditions. Peak solar radiation duration is considered as a priority to compare the results. Melting time is reduced markedly due to irregular distribution of spiral tube planes. Abstract: In the present paper, the charging process of a phase change material (PCM) in a novel heat exchanger called flat spiral tube heat exchanger (FSTH) is investigated for thermal storage purposes. The heat transfer fluid (HTF) flows inside the flat spiral tubes which are propagated throughout the shell. The so-called heat exchanger is examined considering various geometrical and operational boundary conditions. Variables such as a change in coil number of each flat spiral tube plane (FSTP), shell's tilt angle and the distribution of flat spiral tube planes throughout the shell along with HTF mass flow rate and HTF inlet temperature are investigated in this research numerically. Temperature, heat flux, the stored energy fraction, and liquid fraction contours along with PCM average temperature and melting procedure are examined in details. Simulation results indicate that the irregular distribution of FSTPs throughout the shell has a significant effect on the melting process and heat transfer procedure. Furthermore, vertical configurations are found to be more capable to store the PCM's energy in a specified duration of maximum solar radiation.