Numerical study of a multiple-segment metal foam-PCM latent heat storage unit: Effect of porosity, pore density and location of heat source

Talebizadehsardari, Pouyan; Mohammed, Hayder I.; Giddings, Donald; Walker, Gavin S.; Gillott, Mark; Grant, David M.

doi:10.1016/j.energy.2019.116108

Cited by 137 publications

(31 citation statements)

References 63 publications

(72 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…is the pore Reynolds number, and d f , d p , and ω are the ligament diameter, the pore size, and the pore density, respectively. As the LTNE assumption was invoked in present the study, the effective thermal conductivity could be calculated as follows [9,34,35]:…”

Section: Metal Foam Parametersmentioning

confidence: 99%

“…They indicated that an optimized positive porosity gradient (0.89-0.95-0.98) is better suited to further decrease the melting time than a uniform gradient. Sardari et al [9] investigated the porosity and pore size effects of metal foams on the PCM melting process. They stated that inserting porous foam with low porosity provides high performance and decreases the melting time by 85% compared to PCM alone.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Insight into Foam Pore Effect on Phase Change Process in a Plane Channel under Forced Convection Using the Thermal Lattice Boltzmann Method

et al. 2020

View full text Add to dashboard Cite

In this work, the two-dimensional laminar flow and the heat transfer in an open-ended rectangular porous channel (metal foam) including a phase change material (PCM; paraffin) under forced convection were numerically investigated. To gain further insight into the foam pore effect on charging/discharging processes, the Darcy–Brinkmann–Forchheimer (DBF) unsteady flow model and that with two temperature equations based on the local thermal non-equilibrium (LTNE) were solved at the representative elementary volume (REV) scale. The enthalpy-based thermal lattice Boltzmann method (TLBM) with triple distribution function (TDF) was employed at the REV scale to perform simulations for different porosities (0.7≤ε≤0.9) and pore per inch (PPI) density (10≤PPI≤60) at Reynolds numbers (Re) of 200 and 400. It turned out that increasing Re with high porosity and PPI (0.9 and 60) speeds up the melting process, while, at low PPI and porosity (10 and 0.7), the complete melting time increases. In addition, during the charging process, increasing the PPI with a small porosity (0.7) weakens the forced convection in the first two-thirds of the channel. However, the increase in PPI with large porosity and high Re number limits the forced convection while improving the heat transfer. To sum up, the study findings clearly evidence the foam pore effect on the phase change process under unsteady forced convection in a PCM-saturated porous channel under local thermal non-equilibrium (LTNE).

show abstract

Section: Metal Foam Parametersmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Insight into Foam Pore Effect on Phase Change Process in a Plane Channel under Forced Convection Using the Thermal Lattice Boltzmann Method

et al. 2020

View full text Add to dashboard Cite

show abstract

“…However, carefully designed fins have been shown to be as efficient as introducing metal foam in the system [ 34 ]. Melting time is also shown to be proportional to the porosity of an added foam but inversely proportional to the fraction of the enclosure that is filled with foam [ 35 , 36 ].…”

Section: Introductionmentioning

confidence: 99%

Phase-Transition Thermal Charging of a Channel-Shape Thermal Energy Storage Unit: Taguchi Optimization Approach and Copper Foam Inserts

et al. 2021

View full text Add to dashboard Cite

Thermal energy storage is a technique that has the potential to contribute to future energy grids to reduce fluctuations in supply from renewable energy sources. The principle of energy storage is to drive an endothermic phase change when excess energy is available and to allow the phase change to reverse and release heat when energy demand exceeds supply. Unwanted charge leakage and low heat transfer rates can limit the effectiveness of the units, but both of these problems can be mitigated by incorporating a metal foam into the design of the storage unit. This study demonstrates the benefits of adding copper foam into a thermal energy storage unit based on capric acid enhanced by copper nanoparticles. The volume fraction of nanoparticles and the location and porosity of the foam were optimized using the Taguchi approach to minimize the charge leakage expected from simulations. Placing the foam layer at the bottom of the unit with the maximum possible height and minimum porosity led to the lowest charge time. The optimum concentration of nanoparticles was found to be 4 vol.%, while the maximu possible concentration was 6 vol.%. The use of an optimized design of the enclosure and the optimum fraction of nanoparticles led to a predicted charging time for the unit that was approximately 58% shorter than that of the worst design. A sensitivity analysis shows that the height of the foam layer and its porosity are the dominant variables, and the location of the porous layer and volume fraction of nanoparticles are of secondary importance. Therefore, a well-designed location and size of a metal foam layer could be used to improve the charging speed of thermal energy storage units significantly. In such designs, the porosity and the placement-location of the foam should be considered more strongly than other factors.

show abstract

“…Further, they showed that utilizing a combined porous/PCM unit increases the rate of heat transfer between10-and 18-times during melting and solidification processes. Sardari et al 8,43,44 presented the application of composite porous/PCM in energy storage air heaters in domestic buildings. They compared the combination of the porous/PCM and the alone-PCM units and they found significant advantages of the metal foam on the unit.…”

Section: Introductionmentioning

confidence: 99%

Effect of airflow channel arrangement on the discharge of a composite metal foam‐phase change material heat exchanger

et al. 2020

Self Cite

View full text Add to dashboard Cite

Summary The effect of various arrangements of airflow channel in a proposed storage heater based on copper foam soaked in a phase change material (PCM) is investigated. Different configurations of the air channel using a serpentine channel, as well as numbers of the air channels, are examined in a representative three‐dimensional computer‐based model (Ansys Fluent). Evaluation is performed by PCM discharging rate and output air temperature of the unit. The goal is to improve both uniformity and value of air temperature. Changing the airflow arrangement using serpentine configuration to increase heat exchange surface area reduces solidification time and increases output maximum air temperature as well as pressure drop; conversely, exit air achieves lower temperature uniformity. In the case of the shortest solidification time using one air‐channel with the length of 51 cm, the solidification time reduces to almost 6 hours, compared with 13.6 hours for the straight channel with 37 cm length, with the average output temperature of 56°C compared to 41°C for the straight channel; however, the achieved temperature difference from the initial to the end of solidification time is 13.7°C compared to 4.5°C for the straight tube.

show abstract

Numerical study of a multiple-segment metal foam-PCM latent heat storage unit: Effect of porosity, pore density and location of heat source

Cited by 137 publications

References 63 publications

Insight into Foam Pore Effect on Phase Change Process in a Plane Channel under Forced Convection Using the Thermal Lattice Boltzmann Method

Insight into Foam Pore Effect on Phase Change Process in a Plane Channel under Forced Convection Using the Thermal Lattice Boltzmann Method

Phase-Transition Thermal Charging of a Channel-Shape Thermal Energy Storage Unit: Taguchi Optimization Approach and Copper Foam Inserts

Effect of airflow channel arrangement on the discharge of a composite metal foam‐phase change material heat exchanger

Contact Info

Product

Resources

About