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This paper presents the designing aspects and first experimental characterization of an adaptable Smart Modular Heat Recovery Unit (SMHRU) developed under the scope of the E2VENT Project. This SMHRU is being designed as a part of an adaptable renovation module for the retrofitting of multi-storey residential building from the 60's, 70's across Europe that embeds the SMHRU and an energy storage system based on a phase change material. This heat recovery unit will be adjustable to be integrated into the ventilated façade cavity, and able to recover heat from ventilation air, preheating the ventilation air in winter and precooling it in summer. This will allow an efficient combination of consumption reduction and acceptable air indoor quality. The first part of the paper presents designing considerations and thermal stationary analysis of the heat recovery unit, which is based on experimental correlations obtained for air-to-air compact offset-strip-fin plate heat exchangers. Secondly CFD analysis of the distributor of the SMHRU is presented. Finally prototype first performance estimation based on experimental results is presented. ; This work has been developed under the project "E2VENT: Energy Efficient Ventilated Façades" funded by the Horizon 2020 framework of the European Union, Project No. 637261.

Ventilated façade systems, incorporating thermal insulation behind a rear-ventilated cladding, constitute a popular renovation solution in warm European climates. For compliance with building regulations, their energy efficiency is usually obtained through simple onedimensional desktop calculations, which do not consider the impact of the support elements of the cladding penetrating the thermal insulation. This study assesses a ventilated façade system anchored over a solid concrete wall with adjustable stainless steel brackets. One-dimensional calculations are compared against three-dimensional numerical thermal modelling, evaluating the effect of insulation thickness (40–100 mm) and potential gaps in the insulation around anchors. Results indicate low risk of condensation and mould growth over internal surfaces. The additional heat flow induced by stainless steel anchors, which is not considered by simplified calculations, appears lower than for aluminium-based systems but can become significant as insulation levels increase. Ensuring the continuity of insulation around anchors is critical for keeping this additional heat flow at reasonable levels (8–13%). If gaps in the insulation are present around anchors, the additional heat flow increases substantially (25–70%) and pushes effective U-values above 0.4 W/m²K, thus resulting in unforeseen energy consumption and noncompliance with regulatory requirements in many European locations. ; This study has been partly developed within the InnoWEE research project. This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 723916. The present paper reflects only the authors' views and neither the Agency nor the Commission are responsible for any use that may be made of the information contained therein.

This article deals with the dynamics of airflow through a cavity. In windless conditions, where a natural flow causes the flow of air in the cavity, the overall aerodynamic resistance of the cavity is the important aerodynamic parameter, which is the sum of the local resistances alongside the air movement trajectory through the cavity. The total aerodynamic resistance of the cavity must be lesses than the force of the convective buoyancy of the air in the cavity. The following conclusions were found experimentally. The convection occurs in the cavity at every time step with a velocity range from 0.05 ≤ v [m/s] ≤ 0.2 to 0.3. The energy regime in the cavity is characterised by inhomogeneity. In the cavity, there are zones of increasing temperatures along the height of the cavity at the inlet. A large area with increased temperatures at the air outlet and a small area with particularly high temperatures in the upper part of the inlet were found.

Unidad de excelencia María de Maeztu MdM-2015-0552 ; In the European Union, the building sector accounts for more than 40% of the total energy consumption and environmental impacts, representing the area with the greatest potential for intervention. In addition to the existing policies that promote energy efficiency in buildings, the embodied energy and the environmental impacts contained in the building materials should be considered. In the case of the construction of insulation façade systems, the environmental implications are different depending on the type of façade system, the insulation materials used and the location of the building. This article aims to provide all of this information for Spain, including not only the production of the components of the façade system but also the installation phase and the transport to the building site. The results show that the most impactful alternative is the ventilated façade combined with the most impactful insulation materials of stone wool and expanded polystyrene. Meanwhile, the most advisable façade in all of the climate zones is the external thermal insulation system combined with any type of insulation. The environmental impacts of insulation materials are very different. Moreover, it is recommended that further studies complete these results with the economic and social implications of the use and maintenance phases for robust decision-making.

Following the Angolan ruling party's crushing defeat of the opposition in the first postwar elections, held in September 2008, the Movement for the Total Liberation of Angola (MPLA) has proceeded to consolidate in the last year its hegemonic rule in the country, effectively giving rise to another African hybrid regime. The regime's security and financial apparatus and national institutions have since been further molded to serve the Presidency and the military and business elites. Having acquired its democratic credentials and secure of the strength of its relevance in the international petroleum arena, Luanda has transformed a once failed state into a reformed autocracy.