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Partial storage strategy can save energy and reduce emissions. In this study, analysis of the partial melting process of ice inserted with nanoparticles inside a square enclosure is investigated for thermal energy storage. The lattice Boltzmann method is for melting and heat transfer in the storage unit. The validation demonstrates strong concurrence between the current findings and the experimental data documented in the literature. The analysis is performed for various Rayleigh numbers, nanoparticle volume fractions, and their effect on melting time and energy storage. Two types of nanoparticles are tested that is, copper and alumina. The outcomes indicate that the Rayleigh number and volume fraction of nanoparticles have a significant impact on the phase change process. The nanoparticles addition leads to homogenous and hence expedited melting process including the final stage of the ice melting process which is very slow without nanoparticles. Furthermore, copper nanoparticles are slightly more effective than alumina. Moreover, using 6% copper nanoparticles can reduce the melting time by up to 12.4%. [ABSTRACT FROM AUTHOR]

Pin fins have the potential to improve the thermal performance of various engineering devices. Modified pin fins could further increase their thermal performance in a passive way at lower cost. This study is aimed at numerically investigating the thermal performance of trenched hemispherical pin fins heat sink (THPFHS) and the influence of parameters including the trench number (N = 1, 3 and 5) and thickness (e = 1 to 5 mm). The simulations were performed using a computational fluid dynamics (CFD) software considering turbulent air flow conditions. Results showed that the use of aluminum fins fitted with one trench in the middle of the hemispherical pin fin considerably increased the local heat transfer. Furthermore, all studied configurations show high thermal performance factor (HTPF) compared with the conventional cylindrical pin fins heat sink (CPFHS). For this new configuration (THPFHS), Nu increases by 45% while the thermal resistance reduces by 42%, compared to the baseline case. On the other hand, this improved performance results in 50% pressure drop penalty. Moreover, the obtained results showed a significant improvement in the performance mainly at high Re. [ABSTRACT FROM AUTHOR]

On a global level the building sector consumes about 45.00% of energy consumption, contributes about 40.00% to emission, uses 30.00% of water and impacts the environment by generating 30.00% of waste. Although windows are important components of a building that provide natural lighting and ventilation and establish necessary contact with the external environment necessary for healthy indoor ambient, they permit entry of undesirable solar heat in summer and allow escaping heat from the indoor ambient in cold seasons, which aggravate the building needs for energy and increase its contribution to atmospheric emissions. The present investigation provides a review on research, development, and applications of advanced windows in the building sector. The introduction highlights the importance and contribution of advanced glazing technology to improving energy, comfort, and thermal performance of buildings. The review includes natural illumination and ventilation, thermal comfort and discusses the effects of window to wall ratio on natural illumination and ventilation of windows and façades. The review also covers recent developments in glazed windows and façades including performance enhancements by using reflective solar films, vacuum glazing, windows with filling materials, windows with water flow, window with phase change material, window with stagnant inert gas filling, ventilated windows and façades and windows with aerogel. A special section was also included on smart glazing for windows and façades showing the new tendencies and applications in the building industry. Since commercial programs and open access codes are handy tools for simulation and performance calculations a section is dedicated to these codes. The conclusion section contains the most relevant conclusion of the review as well as future trends in research and developments in the area. The topics included in this review can be helpful for experienced and young researchers, practicing engineers and general readers interested in windows and façades. [ABSTRACT FROM AUTHOR]