Discharge performance of a high temperature phase change material with low-cost wire mesh

Discharge performance of a high temperature phase change material with low-cost wire mesh

Opolot, Michael (University of Queensland)
Zhao, Chunrong (University of Queensland)
Keane, Partrick F. (University of South Australia)
Liu, Ming (University of South Australia)
Mancin, Simone (University of Padova)
Bruno, Frank (University of South Australia)
Hooman, K. (TU Delft Process and Energy)

Process and Energy

2023

Thermal energy storage is increasingly needed in a sustainable world because of its potential of capturing waste heat and being incorporated in solar power plants. For power generation, in particular, as turbine technology advances, a demand for higher temperature thermal energy storage materials also grows. For this purpose, latent thermal energy storage fits in well since it uses phase change materials (PCMs) which generally have a higher energy density compared to their sensible heat counterparts. In the present study, a eutectic Na₂CO₃(41.69%)-(33.1%)KCl-(25.21%)NaCl phase change material (PCM) with a melting temperature of 569 ° C was chosen as the storage material to experimentally assess the performance benefit of using a readily available stainless steel (ss304) wire mesh (as the periodic structure) to enhance heat transfer within the domain. In addition, for discharging, a numerical model was developed and compared with the experimental results. Furthermore, for discharging, a numerical investigation of the influence of the heat transfer fluid (HTF) flow-rate to the rate of heat transfer was performed. Overall, it was experimentally observed that the charging time for the composite case was shortened by about 35%, compared to the pure PCM case. For discharging, in the axial direction, the composite solidification time when compared to the pure PCM case was on average 10% shorter. Regarding the radial discharging performance of the composite, there was only about 5% improvement compared to the pure PCM case, which was expected due to the thermal contact resistance in the radial direction. Discharging experimental results were used to validate a discharging numerical model. Discharging results from the model showed that increasing the flow rate of the heat transfer fluid (HTF) reduced the time for solidification. It was observed that for the HTF flow rate of 5 L/min, 10 L/min, 20 L/min and 30 L/min, the discharge time was shortened by 23%, 30%, 33% and 35%, respectively.

Experimental testing
Heat transfer
Heat transfer enhancement
Numerical modelling
Phase change materials

http://resolver.tudelft.nl/uuid:df73715a-0d66-43ef-931d-a8777fd53c82

https://doi.org/10.1016/j.applthermaleng.2023.120050

2023-07-14

1359-4311

Applied Thermal Engineering, 223

Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.

Institutional Repository

journal article

© 2023 Michael Opolot, Chunrong Zhao, Partrick F. Keane, Ming Liu, Simone Mancin, Frank Bruno, K. Hooman