A Numerical Study on Time-Dependent Melting and Deformation Processes of Phase Change Material (PCM) Induced by Localized Thermal Input

Kim, Yangkyun; Hossain, Akter; Kim, Sungcho; Nakamura, Yuji

doi:10.5772/23835

Cited by 9 publications

(15 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Good agreement of these numerical simulations with experiment were obtained (see [36]), validating the numerical model applied in the present work.…”

Section: Resultssupporting

confidence: 68%

“…In our previous study [36], 2-D calculation results for convection-diffusion melting in a gallium cavity was performed with the identical modeling method and compared with the experimental result of Gau and Viskanta [37]. Good agreement of these numerical simulations with experiment were obtained (see [36]), validating the numerical model applied in the present work.…”

Section: Resultssupporting

confidence: 54%

See 1 more Smart Citation

Numerical study of melting of a phase change material (PCM) enhanced by deformation of a liquid–gas interface

Kim

Hossain

Nakamura

2013

International Journal of Heat and Mass Transfer

Self Cite

View full text Add to dashboard Cite

Numerical simulations are performed in order to examine the time-dependent melting, and heavily deforming processes of phase change material (PCM) subjected to local heating. By comparing cases with and without deformation, the impact of the inclusion of a deformation model is firstly addressed to understand what influences the precise melting behavior. Mass, momentum and energy conservation equations are solved in a 2-D system based on a fixed grid by means of a finite volume method. The Volume of Fluid (VOF) method and the Enthalpy-Porosity method are applied to model the deformable liquid-gas interface and the melting processes, respectively. Results successfully show the melting, subsequent deformation and dropping-off behavior of the molten PCM. It is found that the inclusion of the deformation model enhances the melting owing to the increase of the total received heat; namely, widening of the contact area at the melting front and induced flow motion inside molten PCM improve the heat transfer toward the melting front. Parametric studies by varying the applied Stefan number so as to change the surface tension are also made to ensure the above-mentioned enhancement mechanism is universally applicable.

show abstract

“…Good agreement of these numerical simulations with experiment were obtained (see [36]), validating the numerical model applied in the present work.…”

Section: Resultssupporting

confidence: 68%

Section: Resultssupporting

confidence: 54%

Numerical study of melting of a phase change material (PCM) enhanced by deformation of a liquid–gas interface

Kim

Hossain

Nakamura

2013

International Journal of Heat and Mass Transfer

Self Cite

View full text Add to dashboard Cite

show abstract

“…In order to represent the heat flow toward the polymer through copper (conductor) satisfactory as noticed in the wire combustion, a localized external thermal input of 500 K is placed on the top surface of the copper to initiate melting of the PCM. We have studied the effect of the temperature of heat source (up to 1400 K) previously (21) , and it has been revealed that melting and dropping processes are physically identical irrespective of the imposed temperature, although the dropping off timing is modified extensively. Since immediate melting and deformation is experienced when the high temperature is imposed as heat source, there would be less chance to observe the thermocapillary effect (we will discuss this in later).…”

Section: Model Descriptionmentioning

confidence: 99%

“…The first term of RHS represents the net effect of the curved surface and gives the normal component force (35) . (22) . As stated, in this study, we choose 500 K (fixed value) of heat source to initiate the melting and subsequent deformation of PCM so that above-tangential force, ∇ s σ T (namely the source of thermocapillary convection), might be under-estimated.…”

Section: Governing Equationsmentioning

confidence: 99%

“…Therefore, in order to understand/model the melting (and the following burning) processes of electric wire precisely, consideration of heat transfer through the conductive material (metal wire core) attached to the polymer is inevitable. Thus, authors made a series of numerical simulation to examine the melting process of Phase Change Material (PCM) subjected to local heating on the copper plate with deformable surface in 2-D system (21)- (22) , as one of simple model of the fire of the electric wire. It has been successfully ensured that the presence of internal fluid motion inside molten PCM could modify melting speed as well as the dropping-off timing.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Numerical Study of Effect of Thermocapillary Convection on Melting Process of Phase Change Material subjected to Local Heating

Kim

Hossain

Nakamura

2013

JTST

Self Cite

View full text Add to dashboard Cite

We numerically investigate the effect of thermocapillary convection on melting and deforming processes of Phase Change Material (PCM) subjected to local heating. Mass, momentum and energy conservation equations are solved in a 2-D system based on a fixed grid by means of a finite volume method. The Volume of Fluid (VOF) method and the Enthalpy-Porosity method are applied to model the deformable liquid-gas interface and the melting processes, respectively. Thermocapillary effect is accounted in the momentum equation as one of additional external force (related to surface tension force and it is controlled by temperature dependency of surface tension coefficient). In this study, temperature dependency of surface tension coefficient is given by linear function of temperature, which is considered as numerical parameter to examine the thermocapillary effect. Results successfully show that the thermocapillary convection under normal gravity environment appears clearly only at the early stage of melting at which the substantial deformation of PCM is not observed. Once the gravity drag starts to deform the molten PCM, thermocapillary convection seems to be masked, revealing that the gravity-induced deformation is dominant factor of internal motion of molten PCM. In zero-gravity, on the other hand, thermocapillary convection is continuously observed, ensuring that it dominates the internal motion so as to enhance the heat flux toward the un-melted solid. Importantly, even in zero-gravity case, the total effect of thermocapillary convection on melting is not so significant, at most 5% in the present system.

show abstract

Scale Modeling of Flame Spread Over PE-Coated Electric Wires

Nakamura

Azumaya

Iwakami

et al. 2014

Progress in Scale Modeling, Volume II

View full text Add to dashboard Cite

A Numerical Study on Time-Dependent Melting and Deformation Processes of Phase Change Material (PCM) Induced by Localized Thermal Input

Cited by 9 publications

References 25 publications

Numerical study of melting of a phase change material (PCM) enhanced by deformation of a liquid–gas interface

Numerical study of melting of a phase change material (PCM) enhanced by deformation of a liquid–gas interface

Numerical Study of Effect of Thermocapillary Convection on Melting Process of Phase Change Material subjected to Local Heating

Scale Modeling of Flame Spread Over PE-Coated Electric Wires

Contact Info

Product

Resources

About