The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Xiaohu Yang - One of the best experts on this subject based on the ideXlab platform.
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thermal performance of a shell and tube latent heat thermal energy storage unit role of annular fins
Applied Energy, 2017Co-Authors: Xiaohu Yang, Qingsong Bai, Qunli Zhang, Liwen Jin, Jinyue YanAbstract:This study conducts numerical investigations on Melting Process in a shell-and-tube latent heat thermal energy storage (LHTES) unit with annular fins. Commercial grade paraffin is employed as the p ...
Jinyue Yan - One of the best experts on this subject based on the ideXlab platform.
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thermal performance of a shell and tube latent heat thermal energy storage unit role of annular fins
Applied Energy, 2017Co-Authors: Xiaohu Yang, Qingsong Bai, Qunli Zhang, Liwen Jin, Jinyue YanAbstract:This study conducts numerical investigations on Melting Process in a shell-and-tube latent heat thermal energy storage (LHTES) unit with annular fins. Commercial grade paraffin is employed as the p ...
Elias Stefanakos - One of the best experts on this subject based on the ideXlab platform.
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the Melting Process of storage materials with relatively high phase change temperatures in partially filled spherical shells
Applied Energy, 2014Co-Authors: Antonio Ramos Archibold, Jose Gonzalezaguilar, Muhammad M Rahman, Yogi D Goswami, Manuel Romero, Elias StefanakosAbstract:A two dimensional axisymmetric model of the heat transfer and fluid flow during the Melting Process inside a spherical latent heat thermal storage capsule is analyzed. A void space was provided within the capsule to take into account the volumetric expansion of the PCM. The mathematical model was solved using the finite-volume method, and the enthalpy-porosity formulation was employed to solve the energy equations in both the liquid and solid regions of the PCM. The effects of the Grashof and Stefan numbers on the thermal performance of the capsules of various diameters (20, 30, 40 and 50mm) have been investigated. It was found that increasing the Grashof number from 1.32×104 to 2. 06×105 enhances the heat transfer. Also for a constant Grashof number (9.09×104) the PCM melts at a faster rate when the Stefan number increases from 0.077 to 0.097. Finally, appropriate dimensionless variables based on a combination of the Fourier, Grashof and Stefan numbers are introduced in order to obtain a generalized correlation for the liquid mass fraction and the Nusselt number during Melting of sodium nitrate.
A Dutta - One of the best experts on this subject based on the ideXlab platform.
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Nano-PCM filled energy storage system for solar-thermal applications
Renewable Energy, 2018Co-Authors: Manar Al-jethelah, Syeda Humaira Tasnim, Shohel Mahmud, A DuttaAbstract:In this paper, a nano-PCM filled enclosure, which is a representative geometry of a thermal energy storage (TES) system, is investigated using scale analysis, numerical simulation, and experimental analysis. The enclosure is assumed to be square in shape. It is also assumed that one vertical wall of the enclosure is actively participating in absorbing energy from a source while the remaining walls are insulated. The thermal boundary condition at the active wall is treated as ‘constant heat flux boundary condition’ in this paper. The energy absorbing material, i.e., the nano-PCM, is CuO nanoparticles dispersed in coconut oil PCM. The influence of the volume fraction of nanoparticles (0≤φ≤5%) is investigated on the flow and thermal fields, heat transfer rate, energy stored and liquid fraction during the Melting Process of nano-PCM at different values of Rayleigh number based on base PCM (104≤Raφ=0%≤108). The Rayleigh number is adjusted by adjusting the size of the enclosure (i.e., higher Ra represents the larger enclosure). In addition to the isothermal lines and velocity vectors, heatlines are utilized to exhibit the energy flow patterns inside the enclosure during the Melting Process. Besides the numerical calculations, scale analysis is presented to demonstrate the different stages of Melting Process of nano-PCM. The detailed scale analysis assists to identify relationship of Nusselt number and solid-liquid interface location as a function of well established dimensionless numbers: Stefan number (Ste), Fourier number (Fo), and Rayleigh number (Raφ=0%). Finally, an experimental setup is developed to visualize the Melting Process of nano-PCM inside a prototype enclosure. Experiments are conducted to illustrate the impact of adding nanoparticles into PCM on the Melting Process. The numerical and experimental results show the significant improvement of the Melting Process by adding nanoparticles to PCM.
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Convection effect on the Melting Process of nano-PCM inside porous enclosure
International Journal of Heat and Mass Transfer, 2015Co-Authors: Syeda Humaira Tasnim, Shohel Mahmud, Rakib Hossain, A DuttaAbstract:Abstract This paper reports thermal performance of porous latent heat thermal energy storage (or LHTES) system filled with nano-phase change material (or nano-PCM). In the first part of the paper, scale analysis is executed to estimate the extent of the complete phase change Process which is a key factor of designing LHTES systems. The scale analysis results in simplified relationships among different non-dimensional parameters (i.e., Fourier number, Stefan number, Rayleigh number, Nusselt number, porosity of the porous medium, and nano particle volume fraction). In the second part, the natural convection Melting Process of nano-PCM inside the porous medium is solved numerically. For the porous medium the Darcy model is employed. The numerical simulation serves two purposes: (i) it verifies the correctness of the relationships proposed by scale analysis in the first part of the paper and (ii) it identifies the effects of nano-particle volume fraction, time, and Rayleigh number, on flow field, thermal field, and heat transfer Process during the Melting of nano-PCM inside the thermal energy storage system. The proposed scaling relationships can be applied to predict the progress and execution of LHTES system filled with porous medium saturated by nano-PCM.
Jizhe Zhang - One of the best experts on this subject based on the ideXlab platform.
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study of ice and snow Melting Process on conductive asphalt solar collector
Solar Energy Materials and Solar Cells, 2011Co-Authors: Mingyu Chen, Hong Wang, Jizhe ZhangAbstract:Abstract This paper investigates the snow Melting Process on asphalt pavements as solar collector by experiments and numerical simulation. A numerical simulation method was used to predict the general design requirements for snow Melting system of asphalt pavements, and a type of experimental asphalt snow Melting system has been built using the design parameters obtained from the preceding simulation. Graphite powders were used to improve the thermal conductivity of asphalt concrete and thus resulting in an improved efficiency of asphalt collector. A laboratory snow Melting test was performed after real snowstorm events. The effects of thermal conductive asphalt concrete (CAC) on snow Melting performance and asphalt pavement temperature distribution were evaluated. The heat transfer in the asphalt slabs and the heat requirement for the snow Melting were analyzed. The results that are obtained show that asphalt solar collector (ASC) provides us a better alternative method for snow Melting. The higher fluid temperature is a positive way to improve the performance of snow Melting system. However, it is unnecessary to keep a too high fluid temperature so as to reduce the waste of energy. The non-uniform temperatures in the asphalt slabs are noticeable. Furthermore, the heat-transmission and the snow Melting performance can be enhanced using CAC.
