2-D numerical investigation of melting of an impure PCM in the arbitrary-shaped annuli

Tabassum, Tonny; Hasan, Mainul; Begum, Latifa

doi:10.1016/j.ijthermalsci.2017.01.006

Cited by 28 publications

(10 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These materials have a moderate melting temperature, high latent melting energy and high heat capacity. Heat generation or absorption inside these materials due to the phase transformation with constant temperature is widely used not only for electronic cooling but also in solar energy storages, building temperature control systems and in other systems [1][2][3][4][5][6][7][8][9][10][11][12][13][14].…”

Section: Introductionmentioning

confidence: 99%

“…Obtained results have shown that fin-length, fin-ratio and angle between neighbor fins have affected the heat transfer enhancement inside the PCM storage system. Tabassum et al [12] have examined the melting process of PCM in the annular gap using the finite volume method. Mathematical model has been formulated on the basis of the enthalpy-porosity approach using the primitive variables.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Numerical Simulation of Natural Convection Melting in 2d and 3d Enclosures

Bondareva¹

2018

Journal of Thermal Engineering

View full text Add to dashboard Cite

Natural convection melting in 2D and 3D enclosures with a local heater is studied numerically. The present research is related to a development of effective cooling system for the electronic devices using the phase change material that is essentially important nowadays. The domain of interest includes vertical cold walls, adiabatic horizontal walls and a discrete heater of constant high temperature located on the bottom adiabatic wall. The cavity is filled with a phase change material (PCM) in solid state at the beginning of the process. During the heating from the heat source PCM is melting. Numerical solution of the present problem has been conducted using the dimensionless transformed variables such as stream function and vorticity for 2D cavity and vector potential functions and vorticity vector for 3D cavity with appropriate initial and boundary conditions. The developed numerical technique has been verified comprehensively. Obtained results have shown a potential of the used methods for 2D and 3D problems. It has been found that, melting process is more intensive in 3D case and the heat transfer rate at the heater is greater for 2D in comparison with 3D data.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Numerical Simulation of Natural Convection Melting in 2d and 3d Enclosures

Bondareva¹

2018

Journal of Thermal Engineering

View full text Add to dashboard Cite

show abstract

“…Most noticeable is the recent trend of the shell-and-tube LHS unit being integrated into solar thermal power systems, as seen in the applications studied by Li et al [4] and Tehrani et al [5]. Consequently, the shell-and-tube type LHS unit was the subject of a number of analytical [6][7][8][9], experimental [10][11][12][13], and numerical [14][15][16][17][18][19][20][21][22] studies, which focused mostly on performance enhancements at the charging/discharging-stage of the unit.…”

Section: Introductionmentioning

confidence: 99%

“…It was found that proper arrangements of the hierarchical inner tube design can decrease melting time. Along the same line of geometric investigations, Darzi et al [16], Tabassum et al [19], and Kuboth et al [21] explored new ideas of geometrically altering the shell-and-tube type LHS unit to enhance the heat transfer performance.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Numerical Simulation and Optimization of the Melting Process of Phase Change Material inside Horizontal Annulus

Chen

Sun

2017

Energies

View full text Add to dashboard Cite

Latent heat storage (LHS) technologies adopting phase change materials (PCMs) are increasingly being used to bridge the spatiotemporal mismatch between energy production and demand, especially in industries like solar power, where strong cyclic fluctuations exist. The shell-and-tube configuration is among the most prevalent ones in LHS and thus draws special attention from researchers. This paper presents numerical investigations on the melting of PCM, a paraffin blend RT27, inside a horizontal annulus. The volume of fluid model was adopted to permit density changes with the solidification/melting model wherein natural convection was taken into account. The eccentricity and diameter of the inner tube, sub-cooling degree of the PCM, and the heating-surface temperature were considered as variables for study. Through the evaluation of the melting time and exergy efficiency, the optimal parameters of the horizontal annulus were obtained. The results showed that the higher the heating boundary temperature, the earlier the convection appeared and the shorter the melting time. Also, the different eccentricity and diameters of the inner tube influenced the annulus tube interior temperature distribution, which in turn determined the strength and distribution of the resulting natural convection, resulting in varying melting rates.

show abstract

Implications of boundary conditions on natural convective heat transfer of molten phase change material inside enclosures

Arıcı

Yıldız

Nižetić³

et al. 2020

Int J Energy Res

View full text Add to dashboard Cite

Summary Considering the significance of the appropriate selection of boundary conditions (BCs) in modelling step for practical engineering applications, this study presents a numerical work focusing on the impacts of BCs on the natural convection of molten phase change material (PCM) used for cooling of photovoltaics (PV). A rectangular enclosure loaded with liquid PCM (Pr = 41.22) is considered at an inclination angle of θ = 30° to simulate a PV‐PCM system. Heat flux is applied to the top wall, and impacts of two different BCs at the bottom wall, namely isothermal and convective BCs, on the flow and heat transfer characteristics are compared by taking six different Biot numbers (0.1 ≤ Bi ≤ 100) into account, while the reference case is considered as isothermal BC. Furthermore, the effects of various aspect ratios (AR = 1, 2 and 4) and Rayleigh numbers (Ra = 104, 105 and 106) are also included. The results revealed that Biot number has a significant effect on mean Nusselt number. Compared to the isothermal case, low Biot numbers (Bi < 10) significantly restrict convection motions inside the enclosure and result in remarkably different mean Nusselt numbers, while high Biot numbers give significantly similar results due to low thermal resistance outside the bottom wall. Moreover, the heat transfer enhancement by increasing AR and Ra is considerably high at high Biot numbers, while it is remarkably constricted at low Biot numbers. As a result of comprehensive analyses, it is deduced that utilization of isothermal BCs instead of convective BC for easiness of modelling can be a reasonable approach providing that Biot number is sufficiently large (Bi > 10). Although the inspiration of the present study is PV/PCM systems, the results can be generalized for any kind of fluids used in similar natural convection applications.

show abstract

2-D numerical investigation of melting of an impure PCM in the arbitrary-shaped annuli

Cited by 28 publications

References 25 publications

Numerical Simulation of Natural Convection Melting in 2d and 3d Enclosures

Numerical Simulation of Natural Convection Melting in 2d and 3d Enclosures

Numerical Simulation and Optimization of the Melting Process of Phase Change Material inside Horizontal Annulus

Implications of boundary conditions on natural convective heat transfer of molten phase change material inside enclosures

Contact Info

Product

Resources

About