282 research outputs found

    Electric vehicles and urban noise control policies

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    "jats:p"Limited Traffic Zone (LTZ) is a planning strategy that is more and more adopted by municipalities in Europe to improve their environmental conditions. It consists in the prohibition for traditional vehicles to circulate in specific areas. Although the main aim is to tackle air pollution problems, positive effects are registered in terms of reduction of noise annoyance and in terms of improved “quality of life” if specific conditions are respected. On the other side under the drive of the global market, the number of circulating electric vehicles in urban sites is also increasing. In the next years we expect to experience a new and not well-known urban soundscape."/jats:p" "jats:p"In this paper is presented an overview of recent urban projects and policies that deal with noise control and how these experiences will match into the next years with the sound characteristics of new electric vehicles for private and public transportation. Document type: Articl

    Sound Water Masking to Match a Waterfront Soundscape with the Users’ Expectations: The Case Study of the Seafront in Naples, Italy

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    In the last decades, the soundscape approach has attracted the attention of architects and urban planners, leading them to incorporate the acoustic features into the enjoyment of their creations. One of the key aspects for an appreciated urban environment is to match the expectations of the users. In this study, the matching of the waterfront soundscape with the users’ expectations is evaluated by laboratory tests using semantic differential scales applied to reproduced virtual scenarios obtained adding different water sound pressure levels (SPLs) to the original in-situ setting. The tests were carried out by an immersive virtual reality (IVR) device, using 360◦ videos and spatial audio recorded in two sites of the waterfront in Naples, Italy. The scenarios were presented to the participants according to three experimental protocols, namely audio-only (A), video-only (V), and simultaneous audio-video (AV) reproduction. The examined different acoustic scenarios were the original one recorded in situ and others obtained adding seawater sounds at SPL increments of 5 dB. The results show that all the scenarios with water sounds added are rated more pleasant than the original one for the audio-only scenario. When video and audio are displayed simultaneously, two scenarios are more pleasant than the original one, likely because there is a need for coherence between the water sound SPL heard and the visible noise sources. Sounds coherent with the type of shore show a higher matching with expectations and pleasantness appraisals, rather than those that are uncoherent with the layout scenario

    Intercultural Differences in the Perception of HVAC Sound Quality in Car Cabins: From Conventional to Electric Vehicles

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    In electric-powered cars, the production of which is increasing, the HVAC system is responsible for most of the noise inside the car’s cabin, causing significant discomfort for passengers. Moreover, the noise produced by the HVAC affects the perceptible sound inside the car cabin, significantly impacting the perceived quality of the vehicle. It is thus essential to investigate and quantify people’s preferences concerning HVAC noise. Our previous research revealed differences in the HVAC noise between hybrid electric (HEV) and internal combustion engine (ICEV) vehicles. A subsequent factor analysis revealed that the adjectives used to describe the sounds can be grouped into two main dimensions: Aesthetic and Loudness. The present paper highlights the results of a listening test that aimed to identify possible differences in the perception of HVACs’ sound quality between Italian and Japanese subject groups, for ICEV and HEV, in different functioning conditions. Results revealed that the most remarkable difference emerges at high air flow rates, where the Japanese group perceived the quality of sound and annoyance, respectively, to be significantly lower and significantly higher than the Italian group

    Experimental calibration and validation of a simulation model for fault detection of HVAC systems and application to a case study

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    Automated fault detection and diagnostics (FDD) could provide a cornerstone for predictive maintenance of heating, ventilation and air-conditioning (HVAC) systems based on the development of simulation models able to accurately compare the faulty operation with respect to nominal conditions. In this paper, several experiments have been carried out for assessing the performance of the HVAC unit (nominal cooling/heating capacity of 5.0/5.0 kW) controlling the thermo-hygrometric comfort inside a 4.0 Ă— 4.0 Ă— 3.6 m test room at the Department of Architecture and Industrial Design of the University of Campania Luigi Vanvitelli (Italy); then, a detailed dynamic simulation model has been developed and validated by contrasting the predictions with the measured data. The model has also been used to analyze the dynamic variations of key parameters associated to faulty operation in comparison to normal performance, in order to identify simplified rules for detection of any non-optimal states of HVAC devices. Finally, the simulated performance of the HVAC unit has also been investigated while serving a typical Italian building office with and without the occurrence of typical faults with the main aim of assessing the impact of the faults on thermo-hygrometric comfort conditions as well as electric energy consumption

    On the Validity of Immersive Virtual Reality as tool for multisensory evaluation of urban spaces

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    The Europe2020 document indicates a new strategy to turn EU into a smart, sustainable and inclusive economy. At local level urban planning policies may help to reach these aims. Several research works proposed the Immersive Virtual Reality as tool to evaluate the effectiveness of these interventions. Nevertheless people's perception within virtual environments still needs to be verified. In this study, two groups of participants had to provide subjective measures related to the global, acoustic and visual quality of a real environment or of a multisensory reproduced version in Immersive Virtual Reality. Outcomes highlight the ecological effectiveness of this multisensory tool

    Preliminary symptoms assessment of typical faults related to the fans and humidifiers of HVAC systems based on experimental data collected during Italian summer and winter

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    The symptoms associated to the occurrence of typical faults in a heating, ventilation and air-conditioning (HVAC) system, including a single duct dual fan constant air volume air-handling unit, have been experimentally characterized. The operation of the HVAC unit with 3 artificially forced faults ((1) reduced velocity of the supply air fan, (2) reduced velocity of the return air fan, (3) the valve supplying the humidifier kept always closed) has been analysed and compared with that of healthy operation of the same plant under very similar boundary conditions (outside air temperature and initial indoor air temperature) during Italian summer and winter in order to preliminarily assess (i) the effects on the main operating parameters, and (ii) generate preliminary operation data to assist further research in fault detection and diagnosis of HVAC systems

    Healthy and Faulty Experimental Performance of a Typical HVAC System under Italian Climatic Conditions: Artificial Neural Network-Based Model and Fault Impact Assessment

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    The heating, ventilation, and air conditioning (HVAC) system serving the test room of the SENS i-Lab of the Department of Architecture and Industrial Design of the University of Campania Luigi Vanvitelli (Aversa, south of Italy) has been experimentally investigated through a series of tests performed during both summer and winter under both normal and faulty scenarios. In particular, five distinct typical faults have been artificially implemented in the HVAC system and analyzed during transient and steady-state operation. An optimal artificial neural network-based system model has been created in the MATLAB platform and verified by contrasting the experimental data with the predictions of twenty-two different neural network architectures. The selected artificial neural network architecture has been coupled with a dynamic simulation model developed by using the TRaNsient SYStems (TRNSYS) software platform with the main aims of (i) making available an experimental dataset characterized by labeled normal and faulty data covering a wide range of operating and climatic conditions; (ii) providing an accurate simulation tool able to generate operation data for assisting further research in fault detection and diagnosis of HVAC units; and (iii) evaluating the impact of selected faults on occupant indoor thermo-hygrometric comfort, temporal trends of key operating system parameters, and electric energy consumptions

    Thermal Performance of an Electric-Driven Smart Window: Experiments in a Full-Scale Test Room and Simulation Model

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    This paper reports the results of experimental tests and numerical simulations aimed at evaluating the performance of an electric-driven smart window with respect to solar control in buildings. The experimental performances of the electric-driven smart window were evaluated using a south oriented full scale experimental facility designed and realized. The tests were carried out during the summer under real sky conditions upon varying the state of the electricdriven smart window (clear and milky). In the first part of the paper, the experimental results are discussed in terms of surface temperature of glazings as well as indoor air temperature in order to highlight the potential benefits on thermal comfort associated to the application of electric-driven smart windows. In the second part of this paper, the experimental data are compared to the numerical results generated through a simulation model of the electric-driven smart window in order to assess its reliability under different operating scenarios. Finally, the simulation model is used to quantify the potential cooling load reduction deriving from the integration of electric-driven smart windows in an office façade located in Naples (Italy)

    The Restorativeness of Outdoor Historical Sites in Urban Areas: Physical and Perceptual Correlations

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    Growing tourist flows, which crowd ancient city centres, have modified their liveability and threatened conservation. They have increased the need for quiet places, primarily where green parks are missing. While previous studies have highlighted the possibility of reusing hidden sites of historical buildings, it is not clear if this scheme can also be applied in other contexts, and which physical or perceptual dimensions are mainly related to the restoration of these sites. If greenery and water elements induce positive effects on people’s well-being, we want to understand if the historical–artistic component can be just as important for people’s restorativeness. To this end, the physical and perceptual characteristics of 20 different sites in Naples and Istanbul were investigated through objective and subjective surveys. The results show that the sound levels inside sites cannot consistently account for the perception of the restorativeness in Italy and Turkey, while some sound level differences caused by outside noise could. Moreover, soundscape, appreciation, maintenance/management, and importance/relevance were the main perceptual dimensions describing these places. The importance/relevance dimension was strongly correlated with all the components of the restorativeness, especially with the fascination. These findings are consistent between the Italian and Turkish groups

    Faulty Operation of Coils’ and Humidifier Valves in a Typical Air-Handling Unit: Experimental Impact Assessment of Indoor Comfort and Patterns of Operating Parameters under Mediterranean Climatic Conditions

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    Data-driven Automated Fault Detection and Diagnosis (AFDD) are recognized as one of the most promising options to improve the efficiency of Air-Handling Units (AHUs). In this study, the field operation of a typical single-duct dual-fan constant air volume AHU is investigated through a series of experiments carried out under Mediterranean (southern Italy) climatic conditions considering both fault-free and faulty scenarios. The AHU performances are analyzed while artificially introducing the following five different typical faults: (1) post-heating coil valve stuck at 100% (always open); (2) post-heating coil valve stuck at 0% (always closed); (3) cooling coil valve stuck at 100% (always open); (4) cooling coil valve stuck at 0% (always closed); (5) humidifier valve stuck at 0% (always closed). The measured faulty data are compared against the corresponding fault-free performance measured under the same boundary conditions with the aim of assessing the faults’ impact on both thermal/hygrometric indoor conditions, as well as patterns of 16 different key operating parameters. The results of this study can help building operators and facility engineers in identifying faults’ symptoms in typical AHUs and facilitate the related development of new AFDD tools
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