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
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