Thermal Stratification Performance of a Packed Bed Latent Heat Storage System during Charging

Experimental thermal stratification evaluation of a packed bed latent heat storage is done during charging cycles. The packed bed latent heat storage system consists of adipic acid encapsulated in aluminum spheres. Sunflower oil is used as the heat transfer fluid during charging cycles. Stratification number profiles are used to evaluate thermal stratification in the storage system. Charging experiments are carried out with three different flow-rates (4 ml/s, 8 ml/s and 12 ml/s). Charging experiments are also done using the same flow-rate (8 ml/s) with three different set heater temperatures (220 °C, 240 °C and 260 °C). The lowest charging flow-rate (4 ml/s) shows the best variation of the stratification number profile since it shows the least drop from the peak value and the shortest charging interval. Different set heater temperatures show almost identical stratification number profiles. The effect of the charging flow-rate is more significant than the effect of the charging set heater temperature when evaluating thermal stratification for this particular system.

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Effective Separation of a Water in Oil Emulsion from a Direct Contact Latent Heat Storage System

Energies ◽

10.3390/en11092264 ◽

2018 ◽

Vol 11 (9) ◽

pp. 2264 ◽

Cited By ~ 1

Author(s):

Sebastian Ammann ◽

Andreas Ammann ◽

Rebecca Ravotti ◽

Ludger Fischer ◽

Anastasia Stamatiou ◽

...

Keyword(s):

Heat Transfer ◽

Latent Heat ◽

Direct Contact ◽

Heat Storage ◽

Storage System ◽

Heat Transfer Fluid ◽

Storage Unit ◽

Latent Heat Storage ◽

Oil Emulsion ◽

Water In Oil Emulsion

The problem of emulsification between Phase Change Material (PCM) and Heat Transfer Fluid (HTF) in direct contact latent heat storage systems has been reported in various studies. This issue causes the PCM to flow out of the storage tank and crystallize at unwanted locations and thus presents a major limitation for the proper operation of such systems. These anomalies become more pronounced when high HTF flow rates are employed with the aim to achieve fast heat transfer rates. The goal of this paper is to find a method which will enable the fast separation of the formed emulsion and thus the uninterrupted operation of the storage unit. In this study, three separation methods were examined and the use of superhydrophobic filters was chosen as the best candidate for the demulsification of the PCM and HTF mixtures. The filter was produced by processing of a melamine sponge with different superhydrophobic adhesives and was tested with emulsions closely resembling the ones formed in a real direct contact setup. The superhydrophobic filter obtained, was able to separate the emulsions effectively while presenting a very high permeability (up to 1,194,980 kg h−1 m−2 bar−1). This is the first time the use of a superhydrophobic sponge has been investigated in the context of demulsification in direct contact latent heat storage.

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Experimental study on thermal performance of a novel medium-high temperature packed-bed latent heat storage system containing binary nitrate

Applied Energy ◽

10.1016/j.apenergy.2021.118433 ◽

2022 ◽

Vol 309 ◽

pp. 118433

Author(s):

Wei Wang ◽

Xibo He ◽

Yong Shuai ◽

Jun Qiu ◽

Yicheng Hou ◽

...

Keyword(s):

Experimental Study ◽

High Temperature ◽

Latent Heat ◽

Thermal Performance ◽

Heat Storage ◽

Storage System ◽

Packed Bed ◽

Latent Heat Storage

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Erratum to “Numerical heat transfer analysis of the packed bed latent heat storage system based on an effective packed bed model” [Energy 35 (2010) 2022–2032]

Energy ◽

10.1016/j.energy.2010.06.030 ◽

2010 ◽

Vol 35 (10) ◽

pp. 4244

Author(s):

L. Xia ◽

P. Zhang ◽

R.Z. Wang

Keyword(s):

Heat Transfer ◽

Latent Heat ◽

Heat Storage ◽

Storage System ◽

Packed Bed ◽

Heat Transfer Analysis ◽

Latent Heat Storage ◽

Numerical Heat Transfer

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Experimental Investigation of a Packed-Bed Latent Heat Thermal Storage System With Encapsulated Phase Change Material

Volume 6B: Energy ◽

10.1115/imece2014-38307 ◽

2014 ◽

Cited By ~ 10

Author(s):

Tanvir E. Alam ◽

Jaspreet Dhau ◽

D. Y. Goswami ◽

M. M. Rahman ◽

Elias Stefankos

Keyword(s):

Heat Transfer ◽

Experimental Study ◽

Latent Heat ◽

Flow Rate ◽

Storage System ◽

Volumetric Flow Rate ◽

Packed Bed ◽

Heat Transfer Fluid ◽

Encapsulated Phase Change Material ◽

Change Material

An experimental study on a laboratory scale prototype packed-bed latent heat thermal energy storage (TES) system is presented. Spherical capsules of sodium nitrate melting point of 306°C were used as the PCM and air was used as the heat transfer fluid (HTF). The storage system was operated between 286°C to 326°C and the volumetric flow rate of the HTF was varied from 110 m3/hr to 151 m3/hr. Temperature distribution along the bed and inside the capsules was monitored continuously during charging and discharging of the system. The effect of mass flow rate of the HTF on the charging and discharging time and on the pressure drop across the bed was also evaluated.

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