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This work is aimed at the experimental characterisation of air quality and thermal profile within an electric vehicle cabin, measuring at the same time the HVAC system energy consumption. Pollutant concentrations in the vehicle cabin are measured by means of a low-cost system of sensors. The effects of the HVAC system configuration, such as fresh-air and recirculation mode, on cabin air quality, are discussed. It is shown that the PM concentrations observed in recirculation mode are lower than those in fresh-air mode, while VOC concentrations are generally higher in recirculation than in fresh-air mode. The energy consumption is compared in different configurations of the HVAC system. The novelty of this work is the combined measurement of important comfort parameters such as air temperature distribution and air quality within the vehicle, together with the real time energy consumption of the HVAC system. A wider concept of comfort is enabled, based on the use of low-cost sensors in the automotive field.

The present study investigates the planar Couette flow problem for low Reynolds numbers inside a rectangular duct with a morphing cavity serving as a vortex formation promoter. A finite element code implemented in COMSOL Multiphysics is employed to analyze the effects of the cavity aspect ratio and variations of the Reynolds number on formation and topology of the vortices within the embedded cavity. The obtained results indicate that the cavity height is influential in the number of vortices. It is shown by increasing the Reynolds number, a single vortex tends to move towards the outlet. In addition, streamlines demonstrate that small vortices in vicinity of the cavity corner tend to be enlarged with increase of the Reynolds number. The developed numerical model can be extended to the flow structure of natural systems such as an embayment subjected to parallel-to-shore currents.

The present study examines the possibility of thermal comfort optimisation inside an office room where, due to historical heritage, it is possible to modify neither the energetic characteristic of the envelope nor the position of the inlet air vents. The distribution of global and local thermal comfort indices is evaluated in both heating and cooling conditions by establishing a computational fluid dynamics (CFD) model validated against experimental data. The obtained results demonstrate a striking asymmetry of the air velocity and temperature distribution due to the low energy efficiency of the building. In heating mode, the predicted mean vote ( P M V ) values were improved if the discharged air from the fan coil was at its maximal velocity. However, at the same time, the vertical air temperature gradient increased by around 0.5 ° C in each working station. In the cooling condition, in the absence of the solar radiation, the minimal air-flow rate satisfied the acceptable range of the draught rate ( D R ), whereas in the presence of a solar load, it could not meet the required cooling load in all positions, leading to higher floor temperature. The findings of this study allow for identifying and rearranging the optimal position of working stations in terms of thermal comfort. [ABSTRACT FROM AUTHOR]

An accurate assessment of thermal comfort inside a building is essential since it is associated to the human's perception of well-being and comfort. In the present study, a 3D computational fluid dynamic (CFD) code is employed to evaluate the indoor comfort indexes for a university office located in a historical building, built of thick masonry walls and of large single-glass windows, using fan coil as an air conditioning system. The experimental measurement has been carried out to validate the numerical model and to obtain the required initial and boundary conditions. The experimental set-up employs an innovative system for the sensor localization, based on acoustic sources, signal processing and trilateration algorithms. By means of finite volume method, the turbulent air flow, the local heat transfer characteristics and the operative temperature inside the room are obtained for a typical winter day. The results yielded by numerical simulations allow to evaluate thermal comfort condition at working places inside the office and to identify the best comfort areas. The results show that even when the air temperature is quite uniform inside the room, the operative temperature at the positions where occupants are placed is significantly affected by surface temperature of the windows, due to the large window to wall surface ratio and also by the position and operational condition of fan coil. It is concluded that 3D comfort map allows to optimize internal layout of the office room; furthermore, the possibility of thermal comfort optimization in specific workstation together with local control of heating system lead to gain remarkable energy saving results. [ABSTRACT FROM AUTHOR]

The epidemiological characteristics of spontaneous hypercortisolism (HC) were derived from 21,281 client-owned dogs selected from four private veterinary clinics and one university reference center for endocrinology. The odds ratio (OR) method was employed to investigate the risk of developing HC related to breed, gender, and sexual status. The estimated prevalence of HC in the four private clinics was 0.20% [95% confidence interval (CI), 0.13-0.27] and was significantly different compared to the university reference center (1.46%; 95% CI, 1.12-1.80). Sex, breed, and age resulted in risk factors for HC. Mean (± SD) age for dogs with HC was 9.8 (± 2.5) yr. Females had higher risk for HC compared to males (OR 1.85; 95% CI, 1.24-2.75); all neutered dogs (both males and females) had higher risk than intact dogs (OR 2.54; 95% CI, 1.72-3.73); and neutered females had higher risk compared to intact females (OR 2.61; 95% CI, 1.54-4.42). Using the mixed breed dogs as a control population (OR = 1), the risk of developing HC was significantly higher in the Standard Schnauzer (OR 58.1; p < 0.0001) and Fox Terrier (OR 20.33; p < 0.0001). With regard to HC, this study identified an overall prevalence of 0.20%. The data support the existence of sex predisposition, with the highest risk for neutered females. [ABSTRACT FROM AUTHOR]

The paper describes the progress of the four-year European project Pro-GET-onE currently under implementation. This research and innovation project is based on the assumption that greater efficiency, attractiveness, and marketable renovation can only be achieved through an integrated set of technologies where all the different requirements (energy, structural, functional) are optimally managed. Thus, the project focuses on the unprecedented integration of different technologies to achieve a multi-benefit approach that is provided by a closer integration between energy and non-energy related benefits. The project aims to combine different pre-fabricated elements in a unified and integrated system resulting in a higher performance in terms of energy requirements, structural safety, and social sustainability. The project attempts to achieve this goal through the introduction of innovative solutions for building envelopes to optimally combine the climatic, structural, and functional aspects through a significant architectural transformation and a substantial increase of the real estate value of the buildings. This augmented value obtained through the application of the inteGrated Efficient Technologies (GETs) is extremely important when considering the necessity of creating an innovative and attractive market in the energy renovation of existing buildings towards the target of nearly zero energy buildings (nZEBs). [ABSTRACT FROM AUTHOR]

Abstract: The analysis of existing built environment shows that the critical values of the peripheral areas, together with the very poor energy performance of existing buildings and the levels of possible transformations they imply, may contribute, collectively, to formulate from light to radical proposals for urban and building retrofitting. In such urban contexts, the reading of urban spaces and the environmental evaluation of their use, both in relation to the intrinsic features of the buildings and with the outdoor spaces, take on a renewed importance. In terms of architectural structure, this importance is focused on the building shell, which can be properly re-thought by proposing new energy efficient technological solutions aimed at re-shaping the technical and formal aspect of the building. These solutions, although developed and conducted on a single building and at the building-level technology, thus contributing to re-function the spatial units, may also been conceived in order to positively affect the urban places and the surrounding environment, fostering a mending relation between the built space and the environmental boundary conditions. [Copyright &y& Elsevier]

Recent earthquakes have highlighted a general inadequacy of the existing building stock in Italy and the need to address this critical issue by increasing its structural resilience. At the same time, the problem of energy consumption in existing residential and commercial buildings is increasingly significant and incompatible with the environmental targets set by governments. Considering all the aforementioned aspects, the seismic upgrading of existing buildings, based on the use of an eco-friendly and sustainable technology, has become more and more relevant and different intervention approaches have been developed. This paper aims to provide a multidisciplinary approach for the performance assessment of an eco-friendly and sustainable RC-framed skin for integrated refurbishment of existing buildings. A preliminary description of such skin technology is provided with particular attention to the simultaneous improvement of structural (e.g., seismic) and non-structural (e.g., energy, acoustic) performances and to issues concerning the limitation of invasiveness and interruption of use of the building. Technological details and in situ installation phases are described with special regard to connection and interaction with the existing building. Procedures for the assessment of upgraded building performances, in terms of seismic capacity and thermo-hygrometric and acoustic performances, are defined and applied to a selected basic cell structure. The feasibility and sustainability of the proposed upgrading intervention is finally investigated by means of a holistic Life Cycle Assessment for environmental impact and Life Cycle Cost for an economic evaluation. Finally, results from a multidisciplinary performance assessment are critically discussed by relating the performance aspects to the technological and installation issues. [ABSTRACT FROM AUTHOR]

Heat recovery ventilation (HRV) systems can be integrated with an additional air heater in buildings with low energy demand in order to cover space heating demand. The employment of coupled HRV-heater systems is, therefore, gaining increasing interest for the improvement of the indoor environmental quality (IEQ), as well as the reduction of ventilation energy loss. The present paper analyses the efficacy of a HRV system, coupled with a low-temperature radiator, in satisfying the IEQ indices inside a retrofitted dormitory room. A computational fluid dynamic (CFD) model based on the finite volume method is established to investigate IEQ characteristics including indoor air quality and thermal comfort condition. The presented CFD code provides a practical tool for a comprehensive investigation of the IEQ indices in spaces employing a coupled HVAC system. In an analysis of indoor air quality, parameters such as age of the air, air change efficiency, and ventilation efficiency in removal of gaseous contaminants, namely VOCs and CO2, are evaluated. The results obtained by the numerical model allow addressing the interaction between HRV and radiator systems and its effects on airflow field. The results show the decrease of the indoor operative temperature with increment of the supply air flow rate, which is mainly due to the decreased thermal efficiency of the HRV system. The obtained results indicate that, while higher ventilation rates can significantly decrease the age of the air and gaseous contaminants level, at the same time, it would cause a local discomfort in some parts of the room. [ABSTRACT FROM AUTHOR]

Given that the issue of variations in geometrical parameters of the borehole heat exchanger (BHE) revolves around the phenomenon of thermal resistance, a thorough understanding of these parameters is beneficial in enhancing thermal performance of BHEs. The present study seeks to identify relative changes in the thermal performance of double U-tube BHEs triggered by alterations in circuit arrangements, as well as the shank spacing and the borehole length. The thermal performance of double U-tube BHEs with different configurations is comprehensively analyzed through a 3D transient numerical code developed by means of the finite element method. The sensitivity of each circuit configuration in terms of the thermal performance to variations of the borehole length and shank spacing is investigated. The impact of the thermal interference between flowing legs, namely thermal short-circuiting, on parameters affecting the borehole thermal resistance is addressed. Furthermore, the energy exchange characteristics for different circuit configurations are quantified by introducing the thermal effectiveness coefficient. The results indicate that the borehole length is more influential than shank spacing in increasing the discrepancy between thermal performances of different circuit configurations. It is shown that deviation of the averaged-over-the-depth mean fluid temperature from the arithmetic mean of the inlet and outlet temperatures is more critical for lower shank spacings and higher borehole lengths. [ABSTRACT FROM AUTHOR]

• Novel approach is presented for evaluating the effectiveness of volume add-ons. • The multidisciplinary benefits are quantified with an innovative SWOT matrix. • The profitability of nearly zero energy target for existing buildings is demonstrated. • The case study of student dormitory in Athens is developed. • Living space is increased of 22% with energy saving of 90%.% This paper proposes a novel multistep approach for comparing several architectural solutions with the aim to create additional volumes on existing buildings by means of the façade transformation. The nearly zero energy standard is the objective of the designing and the criteria for the comparison take into account the minimization of economic impacts and the maximization of comfort conditions for the occupants. An innovative SWOT matrix is proposed for evaluating, with multidisciplinary approach, the results of the refurbishment design. The internal strengths and weaknesses are referred to the building occupants, while external opportunities and threats are referred to the whole society. The proposed approach is applied to the B Building FEPA of the student dormitory in the National and Kapodistrian University of Athens in the frame of a research project financed by HORIZON 2020 funds. With reference to the case study, an increment of around 22% of living space is achieved with energy saving and polluting reduction of around 90%; at the same time the amenity of the outdoor environment, the seismic security, the global comfort are improved. The results of the case study allow to demonstrate how the volume add-ons technique can bring many benefits, not only on the energetic point of view, in the refurbishment of the existing building stock. The awareness of these advantages could encourage occupants, tenants and communities to participate actively in the designing process, and it could be accelerate the achievement of the nearly zero energy standard for the existing building stock. This is the future goal for the sustainable development of the building sector. [ABSTRACT FROM AUTHOR]

This work is aimed at the experimental characterisation of air quality and thermal profile within an electric vehicle cabin, measuring at the same time the HVAC system energy consumption. Pollutant concentrations in the vehicle cabin are measured by means of a low-cost system of sensors. The effects of the HVAC system configuration, such as fresh-air and recirculation mode, on cabin air quality, are discussed. It is shown that the PM concentrations observed in recirculation mode are lower than those in fresh-air mode, while VOC concentrations are generally higher in recirculation than in fresh-air mode. The energy consumption is compared in different configurations of the HVAC system. The novelty of this work is the combined measurement of important comfort parameters such as air temperature distribution and air quality within the vehicle, together with the real time energy consumption of the HVAC system. A wider concept of comfort is enabled, based on the use of low-cost sensors in the automotive field.