Experimental Study and Numerical Simulation on Thermal Energy Storage Characteristics of Composite Phase Change Materials in Annular Space of Vertical Double-Pipe Heat Exchanger

Abstract:

Experimental system on thermal energy storage characteristics of phase change materials (PCMs) in annular space of a vertical double-pipe heat exchanger was set up. The thermal storage performance of paraffin and paraffin/expanded graphite composite PCM with the mass fraction of 70% paraffin was compared. The Fluent software was used to simulate the temperature field of the composite PCM during the thermal storage process. The results show that, for the paraffin, in the sensible heat storage phase, because the heat transfer process is controlled by the heat conduction, the temperature in paraffin gradually reduces from the inside to the outside of the annular space. But for the phase change thermal storage phase, solid-liquid phase change heat transfer is controlled by natural convection and the effect of buoyancy, the temperature in paraffin reduces from top to bottom, from the inside to the outside of the annular space. For the composite PCM, heat transfer is controlled only by the heat conduction process, both the sensible and latent heat storage process, the temperature in the composite PCM decreases from bottom to top, from inside to outside of the annular space. As the thermal conductivity of composite PCM is 15.65 times of paraffin, the thermal energy storage time is shortened by 86.6% than paraffin. The temperature fields of composite PCM in different time are obtained by numerical simulation method, the measured temperatures and simulation results are in good agreement.

• Periodical: Advanced Materials Research (Volume 1053)
• Pages: 143-149
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1053.143
• Online since: October 2014
• Authors: Xiao Hong Liu*, Zi Ye Ling, Peng Sun, Xiao Ming Fang, Tao Xu, Zheng Guo Zhang
• Keywords: Composite Phase Change Material, Expanded Graphite, Numerical Simulation, Thermal Storage

References

[1] F. Kuznik, D. David, K. Johannes, J. J. Roux, A review on phase change materials integrated in building walls, Renewable and Sustainable Energy Reviews, 15(2011) 379-391.

DOI: 10.1016/j.rser.2010.08.019

[2] A. Sharma, V. V. Tyagi, C. R. Chen, D. Buddhi, Review on thermal energy storage with phase change materials and applications, Renewable and Sustainable Energy Reviews, 13(2009) 318-345.

DOI: 10.1016/j.rser.2007.10.005

[3] A. Shukla, D. Buddhi, R. L. Sawhney, Solar water heaters with phase change material thermal energy storage medium: a review, Renewable and Sustainable Energy Reviews, 13(2009) 2119-25.

DOI: 10.1016/j.rser.2009.01.024

[4] F. Agyenim, N. Hewitt, P. Eames, M. Smyth, A review of materials, heat transfer and phase change problem formulation for latent heat thermal energy storage systems (LHTESS), Renewable and Sustainable Energy Reviews, 14(2010) 615-628.

DOI: 10.1016/j.rser.2009.10.015

[5] P. B. Salunkhe, P. S. Shembekar, A review on effect of phase change material encapsulation on the thermal performance of a system, Renewable and Sustainable Energy Reviews, 16(2012) 5603-5616.

DOI: 10.1016/j.rser.2012.05.037

[6] Z. G. Zhang, X. M. Fang, Study on paraffin/expanded graphite composite phase change thermal energy storage material, Energy Conversion and Management, 47(2006) 303-310.

DOI: 10.1016/j.enconman.2005.03.004

[7] Z. G. Zhang, N. Long, X. M. Fang, The research on thermal storage performance of paraffin/expanded graphite composite phase change materials, Journal of Functional Materials, 40(2009) 1313-1315.

[8] A. Sari, A. Karaipekli, Preparation, thermal properties and thermal reliability of palmitic acid/expanded graphite composite as form-stable PCM for thermal energy storage, Solar Energy Materials and Solar Cells, 93(2009) 571-576.

DOI: 10.1016/j.solmat.2008.11.057

[9] A. Karaipekli, A. Sari, Capric-myristic acid/expanded perlite composite as form-stable phase change material for latent heat thermal energy storage, Renewable Energy, 33(2008) 2599-2605.

DOI: 10.1016/j.renene.2008.02.024

[10] L. Xia, P. Zhang, Thermal property measurement and heat transfer analysis of acetamide and acetamide/expanded graphite composite phase change material for solar heat storage, Solar Energy Materials and Solar Cells, 95(2011) 2246-2254.

DOI: 10.1016/j.solmat.2011.03.031

[11] Y. Zhang, J. Y. Zhang, B. Huang, D. X. Li, Experiment test of thermal conductivity coefficient and heat transfer simulation analysis of fatty acids phase change materials, Journal of Functional Materials, 43(2012) 1950-1954, (1959).

[12] Q. Sheng, Y. M. Xing, Experimental and numerical investigation of heat storage/release characteristics of foam composite PCMs, Journal of Functional Materials, 44(2013) 1-5.