Improvement of the Thermal Stratification Inside a Solar Hot Water Storage Tank During Discharging Process

Improvement of the Thermal Stratification Inside a Solar Hot Water Storage Tank During Discharging Process

Mohamed T. Bouzaher* Mohamed Lebbi Hamid Boualit Toufik Chergui Salima Laouar

Unité de Recherche Appliquée en Energies Renouvelables, URAER, Centre de Développement des Energies Renouvelables, CDER 47133, Ghardaïa, Algeria

Corresponding Author Email:
2 May 2018
| |
12 June 2018
| | Citation



In this paper, computational analysis of a full-scale solar hot water storage tank during discharging process is considered. The tank is equipped with four different inlets to improve thermal stratification inside the tank particularly at high water draw-off flow rates. The analysis involves the transient temperature distributions, the flow characteristics and the thermal stratification evolution. The proposed model was validated with experimental data obtained from the literature. Examinations of the vortices interactions and the accompanying temperature contours indicate that thermal gradient and flow mixing are the main factors that affects the stratification efficiency. Results show that the novel proposed inlet forms are able to preserve thermal stratification during dynamic mode.


solar storage tanks, thermal stratification, thermocline thickness, solar heating system

1. Introduction
2. Problem Description
3. Method
4. Results
5. Conclusion

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