Simulation of melting and solidification of graphene nanoparticles-PCM inside a dual tube heat exchanger with extended surface

Abstract. In this study, the effect of fins' height and Stefan number on performance of a shell and tube heat exchanger which contains a phase change material is investigated numerically and experimentally. Melting time, solidification time, liquid mass fraction, melting and solidification front and temperature distribution in different directions (longitudinal, radial and angular) are among criteria for the heat exchangers' comparison. In order to generalize the comparison, melting and solidification fronts are studied for different sections of the shell, fin section and mid-section, for different fins' height during charging and discharging processes. The results show that, these two parameters play important roles in the heat exchanger performance. Increasing Stefan number, the melting time reduces; which exhibits a descending trend in rate when the fins are heightened. In addition, investigating both processes, it can be figured out that increasing fins' height influences the solidification time more significantly than melting.

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Thermal performance enhancement of melting and solidification process of phase-change material in triplex tube heat exchanger using longitudinal fins

Heat Transfer-Asian Research ◽

10.1002/htj.21372 ◽

2018 ◽

Vol 48 (2) ◽

pp. 483-501 ◽

Cited By ~ 5

Author(s):

Jay R. Patel ◽

Manish K. Rathod

Keyword(s):

Heat Exchanger ◽

Phase Change ◽

Phase Change Material ◽

Thermal Performance ◽

Performance Enhancement ◽

Solidification Process ◽

Tube Heat Exchanger ◽

Change Material ◽

Melting And Solidification

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CFD Based Study on an Earth Pipe Heat Exchanger With Different Pipe Geometries

Volume 1: Biofuels, Hydrogen, Syngas, and Alternate Fuels; CHP and Hybrid Power and Energy Systems; Concentrating Solar Power; Energy Storage; Environmental, Economic, and Policy Considerations of Advanced Energy Systems; Geothermal, Ocean, and Emerging Energy Technologies; Photovoltaics; Posters; Solar Chemistry; Sustainable Building Energy Systems; Sustainable Infrastructure and Transportation; Thermodynamic Analysis of Energy Systems; Wind Energy Systems and Technologies ◽

10.1115/es2016-59234 ◽

2016 ◽

Author(s):

Shashank Srivastava ◽

Aashish Sharma ◽

Ketan Ajay

Keyword(s):

Heat Exchanger ◽

Energy Sources ◽

Ground Heat Exchanger ◽

Cfd Modelling ◽

Tube Heat Exchanger ◽

Heating And Cooling ◽

Effective Performance ◽

Extended Surface ◽

Day To Day Operations ◽

Pipe Heat

Heating and cooling is a prime need for various day to day operations and one of the most basic requirements is space conditioning. A huge amount of energy all across the globe is being used for this purpose using various conventional & non-conventional energy based resources. But environmental problems, fast depletion nature and high prices associated with the use of conventional energy sources is becoming a big problem, due to which promotion of non-conventional energy sources becomes important. The use of an in-ground heat exchanger is a unique technique for space conditioning with reduced energy consumption. A lot of research and studies have been done on the design of such systems. This paper presents a study based on the CFD modelling and simulation to analyze the effect on the effective performance of the system by varying the geometry of ducts and using the extended surface to increase the heat transfer rate. Also, a comparative study of performance of earth tube heat exchanger for different cross section of ducts is also presented.

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Experimental Investigation of Phase Change inside a Finned-Tube Heat Exchanger

Journal of Engineering ◽

10.1155/2014/641954 ◽

2014 ◽

Vol 2014 ◽

pp. 1-11 ◽

Cited By ~ 17

Author(s):

M. Rahimi ◽

A. A. Ranjbar ◽

D. D. Ganji ◽

K. Sedighi ◽

M. J. Hosseini

Keyword(s):

Heat Exchanger ◽

Phase Change ◽

Flow Rate ◽

Finned Tube ◽

Melting Time ◽

Inlet Temperature ◽

Rate Variation ◽

Tube Heat Exchanger ◽

Bare Tube ◽

Melting And Solidification

An experimental study is conducted in order to investigate melting and solidification processes of paraffin RT35 as phase change materials in a finned-tube. Therefore the effect of using fins in this study as well as some operational parameters is considered. The motivation of this study is to design and construct a novel storage unit and to compare it with a finless heat exchanger. A series of experiments are conducted to investigate the effect of increasing the inlet temperature and flow rate on the charging and discharging processes of the phase change material. It is shown that, using fins in phase change process enhances melting and solidification procedures. The trend of this variation is different for the heat exchangers; increasing the inlet temperature for the bare tube heat exchanger more effectively lowers melting time. Similarly, flow rate variation varies the solidification time more intensely for the bare tube heat exchanger.

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