| Title | Natural convection effect on solidification enhancement in a multi-tube latent heat storage system: Effect of tubes' arrangement |
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| Author | Ebrahimnataj Tiji, M; Mahdi, J M ; Mohammed, H I; Majdi, H S; Ebrahimi, A; Babaie Mahani, R; Talebizadehsardari, P; Yaïci, W |
| Source | Energies vol. 14, 2021 p. 1-23, https://doi.org/10.3390/en14227489  Open Access |
| Image |  |
| Year | 2021 |
| Alt Series | Natural Resources Canada, Contribution Series 20210577 |
| Publisher | MDPI |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Subjects | Science and Technology; convection; phase relations; energy resources; energy; heat flow |
| Illustrations | schematic diagrams; plots; tables |
| Program | CanmetENERGY - Ottawa Buildings and Renewables Group - Hybrid Energy Systems |
| Released | 2021 11 09 |
| Abstract | The solidification process in a multi-tube latent heat energy system is affected by the natural convection and the arrangement of heat exchanger tubes, which changes the buoyancy effect as well. In the
current work, the effect of the arrangement of the tubes in a multi-tube heat exchanger was examined during the solidification process with the focus on the natural convection effects inside the phase change material (PCM). The behavior of the system
was numerically analyzed using liquid fraction and energy released, as well as temperature, velocity and streamline profiles for different studied cases. The arrangement of the tubes, considering seven pipes in the symmetrical condition, are assumed
at different positions in the system, including uniform distribution of the tubes as well as non-uniform distribution, i.e., tubes concentrated at the bottom, middle and the top of the PCM shell. The model was first validated compared with previous
experimental work from the literature. The results show that the heat rate removal from the PCM after 16 h was 52.89 W (max) and 14.85 W (min) for the cases of uniform tube distribution and tubes concentrated at the bottom, respectively, for the
proposed dimensions of the heat exchanger. The heat rate removal of the system with uniform tube distribution increases when the distance between the tubes and top of the shell reduces, and increased equal to 68.75 W due to natural convection effect.
The heat release rate also reduces by increasing the temperature the tubes. The heat removal rate increases by 7.5%, and 23.7% when the temperature increases from 10 °C to 15 °C and 20 °C, respectively. This paper reveals that specific consideration
to the arrangement of the tubes should be made to enhance the heat recovery process attending natural convection effects in phase change heat storage systems. |
| Summary | (Plain Language Summary, not published)
The solidification process in a multi-tube latent heat energy system is affected by the natural convection and the arrangement of heat exchanger tubes,
which changes the buoyancy effect as well. In the current work, the effect of the arrangement of the tubes in a multi-tube heat exchanger was examined during the solidification process with the focus on the natural convection effects inside the phase
change material (PCM). The behaviour of the system was numerically analysed using liquid fraction and energy released, as well as temperature, velocity and streamline profiles for different studied cases. The arrangement of the tubes, considering
seven pipes in the symmetrical condition, are assumed at different positions in the system, including uniform distribution of the tubes as well as non-uniform distribution, i.e., tubes concentrated at the bottom, middle and the top of the PCM shell.
The model was first validated compared with previous experimental work from the literature. The results show that the heat rate removal from the PCM after 16 h was 52.89 W (max) and 14.85 W (min) for the cases of uniform tube distribution and tubes
concentrated at the bottom, respectively, for the proposed dimensions of the heat exchanger. The heat rate removal of the system with uniform tube distribution increases when the distance between the tubes and top of the shell reduces, and increased
equal to 68.75 W due to natural convection effect. The heat release rate also reduces by increasing the temperature the tubes. The heat removal rate increases by 7.5%, and 23.7% when the temperature increases from 10 °C to 15 °C and 20 °C,
respectively. This paper reveals that specific consideration to the arrangement of the tubes should be made to enhance the heat recovery process attending natural convection effects in phase change heat storage systems. |
| GEOSCAN ID | 329492 |
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