Thermal Performance of a Heat Storage Module Using PCM’s With Different Melting Temperatures: Mathematical Modeling

1989 ◽  
Vol 111 (2) ◽  
pp. 152-157 ◽  
Author(s):  
Mohammed M. Farid ◽  
Atsushi Kanzawa
Keyword(s):  
Temperature Distribution ◽  
Phase Change ◽  
Phase Change Materials ◽  
Heat Storage ◽  
Small Diameter ◽  
Theoretical Models ◽  
Computer Time ◽  
Storage Unit ◽  
Radial Temperature ◽  
Melting Temperatures

In the present study, the performance of a heat storage unit consisting of number of vertical cylindrical capsules filled with phase change materials, with air flowing across them for heat exchange has been analyzed. Earlier theoretical models did not consider temperature distribution in the radial direction within the capsules, an assumption that limits their applications for small diameter capsules. The mathematical model developed in this work is based on solving the heat conduction equation in both melt and solid phases in cylindrical coordinates, taking into account the radial temperature distribution in both phases. Heat flux was then evaluated at the surface of the first row of the capsules to determine the temperature of the air leaving that row by a simple heat balance. It was found that such computation may be carried out for every few rows rather than for a single row to minimize computer time. The simulation study showed a significant improvement in the rate of heat transfer during heat charge and discharge when phase change materials with different melting temperatures were used. Air must flow in the direction of decreasing melting temperature during heat charge, while it must be reversed during heat discharge.

An Improvement in the Solar Water Heating Systems by Thermal Storage Using Phase Change Materials

Solar Energy ◽  
2006 ◽  
Author(s):  
D. Vikram ◽  
S. Kaushik ◽  
V. Prashanth ◽  
N. Nallusamy
Keyword(s):  
Phase Change ◽  
Solar Collector ◽  
Storage Tank ◽  
Phase Change Materials ◽  
Heat Storage ◽  
Control Device ◽  
Hot Water ◽  
Water Heater ◽  
Storage Unit ◽  
Solar Water

The present work has been undertaken to study the feasibility of storing solar energy using phase change materials (like paraffin) and utilizing this energy to heat water for domestic purposes during nighttime. This ensures that hot water is available through out the day. The system consists of two simultaneously functioning heat-absorbing units. One of them is a solar water heater and the other a heat storage unit consisting of Phase Change Material (PCM). The water heater functions normally and supplies hot water during the day. The storage unit stores the heat in PCMs during the day and supplies hot water during the night. The storage unit utilizes small cylinders made of aluminium, filled with paraffin wax as the heat storage medium and integrated with a Solar Collector to absorb solar heat. At the start of the day the storage unit is filled with water completely. This water is made to circulate between the solar collector and the PCM cylinders. The water in the storage tank receives heat form the solar collector and transfers it to the PCM. The PCM undergoes a phase change by absorbing latent heat, excess heat being stored as sensible heat. The water supply in the night is routed to the storage unit using a suitable control device. The heat is recovered from the unit by passing water at room temp through it. As water is drawn from the overhead tank, fresh water enters the unit disturbing the thermal equilibrium, causing flow of heat from PCM to the water. The temperature of the heated water (outlet) is varied by changing the flow rate, which is measured by a flow meter. The storage tank is completely insulated to prevent loss of heat. The performance of the present setup is compared with that of a system using same PCM encapsulated in High Density PolyEthylene (HDPE) spherical shells.

Heat storage unit involving nanoparticle-enhanced phase change materials

2021 ◽  
pp. 515-541
Author(s):  
M. Sheikholeslami ◽  
Elham Abohamzeh ◽  
M. Jafaryar ◽  
Ahmad Shafee
Keyword(s):  
Phase Change ◽  
Phase Change Materials ◽  
Heat Storage ◽  
Storage Unit

Analysis of Heat Transfer Performance for Deepwater Phase Change Material Sandwich Pipes

2019 ◽  
Author(s):  
Chen An ◽  
Hui Wang ◽  
Menglan Duan
Keyword(s):  
Heat Transfer ◽  
Temperature Distribution ◽  
Phase Change ◽  
Phase Change Material ◽  
Deep Sea ◽  
Phase Change Materials ◽  
Insulation Material ◽  
Insulation Layer ◽  
Radial Temperature ◽  
Change Material

Abstract As the exploitation of oil and gas gradually enters the deep sea, the low-temperature and high-pressure deep-sea environment poses a huge challenge to the flow protection of pipelines (2014a). In this paper, the phase change material sandwich pipeline which uses phase change heat storage and exothermic to maintain the pipeline temperature is taken as the research object, the heat transfer characteristics of the deep-water phase change material sandwich pipe are studied through the combination of theoretical analysis and numerical simulation (2014b). The main contents include: Firstly, through the establishment of two-dimensional and three-dimensional pipe models, analyzed the temperature distribution along the pipeline and the radial temperature distribution of the pipeline under steady oil flow conditions. Secondly, by using transient heat transfer, the effects of phase change material parameters, the proportion of phase change material in the insulation layer, and the difference in the ratio of phase change materials in the insulation layer on the insulation performance are analyzed to obtain the best results. Insulation material and optimal insulation layer layout; finally, the thermal storage and the phase change conditions of the phase-change material sandwich pipe is studied under the re-starting condition. The results show that the effective holding time of the phase change material insulation layer is close to 1.4 times that the non-phase change material insulation layer, and the melting point size has little effect on the insulation material. The closer the phase change material is to the inner tube, the better the insulation effect. This study provide guidance for the design and utilization of phase change material sandwich pipe.

Experimental Analysis and Numerical Modeling of a Shell and Tube Heat Storage Unit with Phase Change Materials

2016 ◽  
Vol 55 (29) ◽  
pp. 8154-8164 ◽  
Author(s):  
Tilman Barz ◽  
Christoph Zauner ◽  
Daniel Lager ◽  
Diana C. López Cárdenas ◽  
Florian Hengstberger ◽  
...  
Keyword(s):  
Numerical Modeling ◽  
Phase Change ◽  
Experimental Analysis ◽  
Phase Change Materials ◽  
Heat Storage ◽  
Storage Unit ◽  
Shell And Tube

Effect of Latent Heat to Solidification Process of Phase Change Material

2012 ◽  
Vol 174-177 ◽  
pp. 1214-1218
Author(s):  
Jin Feng Mao ◽  
Wei Hua Li ◽  
Yong Li ◽  
Bo Wang ◽  
Dong Dong Lou ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Phase Transition ◽  
Transition Temperature ◽  
Phase Change ◽  
Latent Heat ◽  
Phase Transition Temperature ◽  
Initial Temperature ◽  
Heat Storage ◽  
Theoretical Models ◽  
Storage Unit

The heat transfer characteristics of heat storage unit are analyzed by many researchers from both theoretical and experimental in solidification heat release. Most theoretical models define the initial temperature of the phase change materials is equal to the phase transition temperature, in fact, thermal storage unit in the application, its initial temperature is not equal to the phase transition temperature. Many theoretical models have not considered the impact of latent heat of solidification. In this paper, homemade inorganic hydrated salt material is used as heat storage media, packaging with a cylindrical container. The phase change heat transfer process was analyzed both from theoretical and experimental. The effect of initial temperature and the latent heat of the heat transfer material were both considered.

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