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• The thermal behavior of a brick-wall impregnating a PCM was modeled and simulated. • Thermal response of the brick with PCM was assessed under summer climatic conditions. • A parametric study was conducted to improve the brick behavior and optimize PCM mass. • The aim was reinforcing the storage capacity and insulation power of this building element. • Integrating PCM in the brick induces better stabilization of the inner surface temperature. In certain Moroccan regions, weather conditions are extreme; the outside ambient temperature varies between 45 °C during the day and 25 °C at night in the estival period. Under such conditions, residential and tertiary buildings, which have lightweight walls, may be vulnerable to internal overheating. Heat waves penetrating the building lead to occupant's discomfort and dissatisfaction. Creating an internal climate, which is independent or slightly dependent on external conditions, can be an appropriate solution to mitigate temperature fluctuations. The adoption of new approaches to improve the thermal inertia of lightweight walls is currently among the most widely accepted techniques in literature. In this study, the integration of phase change material (PCM) in building hollow bricks (widely used in Morocco construction) is proposed to improve the thermal performance of external walls. High latent heat of fusion of PCMs will help to dampen the heat flow through the envelope. Physical modeling and numerical analysis of heat transfer through the hollow bricks containing PCM has been carried out. A parametric study was conducted to evaluate the effect of weather conditions on the thermal response of this building element, also the influence of PCM properties are studied and discussed. It is found that the use of PCM in building bricks stabilizes and reduces the indoor temperature fluctuation. [ABSTRACT FROM AUTHOR]

• The thermal behavior of four bricks incorporating a PCM was studied. • A parametric study has been conducted to improve the bricks thermal behavior. • Integrating PCM in bricks allowed increasing the time lag and reducing fluctuations amplitude. • Volumes of HCBs and clay were reduced up to 30% and 35% for similar thermal behavior. Numerous studies are focused on the thermal behavior evaluation of Hollow Clay Bricks (HCBs) integrating a Phase Change Material (PCM). In the major of these studies, the alveolar space is filled with PCM (macro-encapsulation). However, the air trapped in the alveoli is one of the assets of hollow bricks. Therefore, the present work is focused on the study of the thermal effects of integrating PCM into solid parts of HCBs (micro-encapsulation). Four types of HCBs of different dimensions and alveoli numbers (three, six, eight and twelve alveoli noted HCB-3, HCB-6, HCB-8 and HCB-12 respectively) were investigated. The thermal characteristics of PCM-Bricks such as thermal response, thermal storage capacity and thermal insulation capacity of the various HCBs were numerically evaluated and compared. The 2D-numerical simulations were carried out using Fluent software, based on the finite volume analysis and the enthalpy porosity based method. The results show that HCB type has notable effects on the thermal performance e.g. the phase shift induced by HCB-3, HCB-6, HCB-8 and HCB-12 was respectively of about 1 h, 1 h 43 min, 2 h 27 min and 4 h. In addition, the use of a PCM allowed to improve bricks thermal behavior. The HCB-3 with PCM exhibited equivalent thermal behavior to the HCB-6. Likewise, the HCB-8 with PCM offered equivalent thermal response to that of the HCB-12. Consequently, significant savings in volume, matter and energy have been achieved by introducing PCM in bricks. The volume of HCB has been reduced by up to 30% and a savings on matter was estimated to 35%. [ABSTRACT FROM AUTHOR]

• Comparative Analysis of Various Enhancement Techniques for PCM Heat Transfer. • Investigating the Impact of Fin Number and Shape Arrangement on the Thermal Efficiency of PCM-Filled Heat Sinks. • Assessing the Influence of Copper Nanoparticles Volume Fraction on Heat Transfer within PCM. • Enhancing Heat Transfer in PCM through the Application of Metallic Foam. Efficient cooling of electronic devices presents a persistent challenge in the advancement of electronic technology architecture. Passive cooling strategies employing phase change materials (PCMs) have emerged as promising methods for thermal management. This study employs a numerical analysis to investigate the cooling effectiveness of a heat sink (HS) integrated with PCM, incorporating fins of varying geometries, nanoparticles enhanced phase change material (NCPCM), and metal foam (MF). A comprehensive numerical simulation is performed, considering conjugate heat transfer and melting/solidification processes. The obtained results encompass the base temperature of the heat sink, melting time, enhancement ratio, thermal energy storage (TES), TES rate, and TES density. Through the examination of various fin structures, this study reveals that the inclusion of metal fins in the heat sink yields the lowest base temperature, the longest melting period, and the highest TES rate, especially with the incorporation of 10 fins. However, the addition of copper nanoparticles exhibits limited thermal enhancement despite increasing volume fractions. Notably, the MF+PCM HS demonstrates the lowest base temperature and the highest enhancement in TES rate, achieving a remarkable 12.3% improvement at 95% porosity of copper. [ABSTRACT FROM AUTHOR]

In the present paper, a numerical simulation of natural convection flow in annulus space with a partially heated inner cylinder is proposed. The numerical investigation is based on lattice Boltzmann method (LBM) with multiple relaxation time approximation. Each heating partial side length's is about 25% of the inner perimeter and is maintained at hot temperature. The heated regions are placed on the inner wall in four different configurations while the outer cylinder is maintained at cold temperature. A study of effect of Rayleigh number varying over the range of 104 - 5 × 105 and various cylinder ratio on Nusselt number and both velocity and thermal fields is carried out. It is found that the Nusselt number increases with the increase of Rayleigh number and the radius ratio. Otherwise, the fourth configuration where the heated zones are placed on the left and right sides of the inner cylinder, offers the better rate heat exchange for a fixed value of Rayleigh number and radius ratio. [ABSTRACT FROM AUTHOR]

The trend in energy consumption, with a particular focus on heating and cooling demand, is an issue that is relevant to the promotion of new energy policies and more efficient energy systems. Moreover, heating and cooling energy demand is expected to rise in the next several decades, mainly due to climate change as well as increasing incomes in developing countries. In this context, the building sector is currently a relevant energy-intensive economic sector in Morocco; it accounts for 33% of the country's total energy demand (as the sector with the second highest energy demand, after the transport sector), with the residential sector accounting for 25% and the tertiary sector accounting for 8%. Aiming to reduce energy dependence and promote sustainable development, the Moroccan government recently issued a comprehensive plan to increase the share of renewables and improve energy efficiency. This strategy includes novel thermal building regulations promoted by the Moroccan Agency for Energy Efficiency. This paper analyzes the thermal behavior and heating-cooling energy demand of a residential building located in Tangier (Morocco) as a case example, based on the country's new thermal regulations and considering specific climatological conditions. A comparison with common Moroccan residential buildings as well as with those in nearby countries with similar meteorological conditions but significant differences in terms of energy demand regulation and requirements, such as Spain, is also included. Simulations were carried out using the DesingBuilder and EnergyPlus Software packages. According to the results, the last building thermal regulation requirements in Morocco need to be revised and extended in order to achieve the energy efficiency objectives established by the Moroccan government for 2030. [ABSTRACT FROM AUTHOR]

The trend in energy consumption, with a particular focus on heating and cooling demand, is an issue that is relevant to the promotion of new energy policies and more efficient energy systems. Moreover, heating and cooling energy demand is expected to rise in the next several decades, mainly due to climate change as well as increasing incomes in developing countries. In this context, the building sector is currently a relevant energy-intensive economic sector in Morocco; it accounts for 33% of the country's total energy demand (as the sector with the second highest energy demand, after the transport sector), with the residential sector accounting for 25% and the tertiary sector accounting for 8%. Aiming to reduce energy dependence and promote sustainable development, the Moroccan government recently issued a comprehensive plan to increase the share of renewables and improve energy efficiency. This strategy includes novel thermal building regulations promoted by the Moroccan Agency for Energy Efficiency. This paper analyzes the thermal behavior and heating-cooling energy demand of a residential building located in Tangier (Morocco) as a case example, based on the country's new thermal regulations and considering specific climatological conditions. A comparison with common Moroccan residential buildings as well as with those in nearby countries with similar meteorological conditions but significant differences in terms of energy demand regulation and requirements, such as Spain, is also included. Simulations were carried out using the DesingBuilder and EnergyPlus Software packages. According to the results, the last building thermal regulation requirements in Morocco need to be revised and extended in order to achieve the energy efficiency objectives established by the Moroccan government for 2030. [ABSTRACT FROM AUTHOR]