A novel approach to CFD analysis of the urban environment

The construction of cities, with their buildings and human activities, not only changes the landscape, but also influences the local climate in a manner that depends on many different factors and parameters: weather conditions, urban thermo-physical and geometrical characteristics, anthropogenic moisture and heat sources. Land-cover and canopy structure play an important role in urban climatology and every environmental assessment and city design face with them. Inside the previous frame, the objective of this study is both to identify both the key design variables that alter the environment surrounding the buildings, and to quantified the extension area of these phenomena. The tool used for this study is a 2D computational fluid dynamics (CFD) numerical simulation considering different heights for buildings, temperature gaps between undisturbed air and building’s walls, velocities of undisturbed air. Results obtained allowed to find a novel approach to study urban canopies, giving a qualitative assessment on the contribution and definition of the total energy of the area surrounding the buildings

Air Quality in Portal Areas: An Index for VOCs Pollution Assessment

The main purpose of this chapter is to assess air quality in portal areas considering Volatile Organic Compounds (VOCs) emissions which involve local air pollution and increase climate changes. The methodology adopted foresaw the elaboration of a comparative index, called AQIvoc “Air Quality Index related to VOCs pollution”, weighed on the atmospheric concentrations of each VOCs as well as on the dangerousness of the different analyzed substances. In particular, VOCs dangerousness was estimated in proportion to the emission limit values of each substance according with the Italian regulations. In order to pinpoint the most critical areas of each harbours, the methodology foresees the monitoring of VOCs concentrations and the evaluation of AQIvoc values in each intended use areas inside a portal area. Therefore, four portal areas have been chosen as case studies for testing the methodology and obtaining the first results of the application of the AQIvoc index. Finally, this chapter briefly describes some Best Available Technologies (BAT) and best practices for mitigating VOCs concentrations and for improving local air quality in those areas that were particularly characterized by VOCs pollution

CVD nano-coating of carbon composites for space materials atomic oxygen shielding

The present work analyzes the possibility to employ carbon nanostructures as a basic material to prevent the erosion effects of atomic oxygen suffered by the carbon fiber reinforced polymeric material used in low earth orbit space environment. The application of thin protecting coatings to base materials is a widely used method for preventing the atomic oxygen induced erosion, and thus degradation. The generic purpose is to integrate carbon nanostructures onto carbon composites surface in order to develop the basic substrate of advanced nanocomposite for atomic oxygen protection. The final goal is the characterization of carbon nanostructures-reinforced carbon composites by means of on-ground atomic oxygen simulation facility, with the future objective to assess and optimize the process of carbon-multiscale advanced composites production. With such an aim, a wide investigation on the methane chemical vapor deposition (CVD) over catalyzed carbon fiber-based substrates has been carried out. The as grown nanostructures have been analyzed in terms of morphology, as well as regarding the main features of the resulting growth (yield, purity, homogeneity, coating uniformity, etc.) and the influence of the deposition route operating parameters (catalyst typology, gas flowing rate, growth time/temperature, etc.). A high degree of reproducibility in terms of the relationship between the carbon deposit type/yield and the main process variables (catalyst and protocol) has been thus obtained. Finally, atomic oxygen ground tests have been conducted in order to evaluate the coating process effectiveness. The on-ground test in atomic oxygen environment, with respect to the performances of the reference carbon composites (in terms of total mass loss and atomic oxygen rate of erosion), showed a worsening for the disordered carbon deposit, while an intriguing improvement was achieved by the high-yield carbon nano-filaments deposition

Perceived Quality as Assessment Tool for the Test Case Amore e Psiche Domus in Ostia Antica

Recent years have seen the development of many new ways for cultural heritage visualization; with the growing use of “Information and Communications Technology” (ICT) many 3D reconstructions, virtual tours and “Augmented Reality/Virtual Reality” (AR/VR) application has been developed to enrich the contents of museums, archeological sites and historical places. However, today only few cultural assets have an accurate 3D model with a detailed informative content. In fact, the costs due to the creation of virtual content are still high and they can be addressed only for the most iconic or important monuments. Inside this frame the project RECIPE (REsilience in art CIties: Planning for Emergencies) founded by ESA/ESTEC1 use a crowdsourcing approach, involving tourists and interested people, to acquire cheaply the photos necessary to create photogrammetric models. Such a models to be correctly used inside different level of recording and monitoring tasks, require developing procedure to evaluate their quality. This work discusses, with reference to a study case, only how to validate models by proposing a methodology based on dimensional and color error calculation together with structural indices, such as SSIM and PIQE. Besides to avoid influence generate by different cameras, focus and positioning in photos taken by tourists, the used photo data base has been produced with a professional device following the state of art rules in SfM. At least, it is also discussed the possibility to implement the 3D models in a virtual reality environment to increase their diffusion on new multimedia and interactive plat-forms

A methodological comparison between energy and environmental performance evaluation

The European Union is working on strategies in order to increase the energy efficiency of buildings. A useful solution is to identify the energy performance of buildings through the Energy Performance Certificate (EPC), as it provides information for the comparison of buildings with different architectural typology, shape, design technology and geographic location. However, this tool does not assess the real energy consumption of the building and does not always take into account its impact on the environment. In this work, two different types of analysis were carried out: one based only on the energy efficiency and the other one based on the environmental impact. Those analyses were applied on a standard building, set in three different Italian locations, with the purpose of obtaining cross-related information. After the evaluation of the results, interventions on some parameters (walls insulation, windows frame, filler gas in the insulated glazing) have been identified in order to improve the energy behavior of the building with an acceptable environmental impact. The aim of this paper is to propose a methodology that integrates the EPC with green building rating systems, leading to a more conscious choice of retrofit interventions as a compromise between energy performances and environmental impact

A Method to Evaluate the Stimulation of a Real World Field of View by Means of a Spectroradiometric Analysis

Stimulation elicited by a real world field of view is related to the color, the intensity and the direction of the information reaching the eye: different spectral power distributions of light trigger different responses. An evaluation of the stimulation provided by the field of view can be performed by measuring the spectral radiance with a spectroradiometer and weighting this data with an efficiency curve. Different weights (physical, physiological and psychological) can lead to different analyses and consequently to different results. The proposed method allows an overall and simplified evaluation of the field of view based on spectral and luminance measures and a script that processes the luminous information. The final aim of this approach is to provide further information about the light stimulation reaching the retina and to supply a qualitative evaluation of the field of view, allowing to know how much stimulation is coming from a certain area within the visual field depending on the type of surface, basing on spectral and directional information. This approach can have practical implications, allowing technicians and designers to take into consideration the possible visual fields, in order to properly shape the features of stimulation throughout the day, hence following a field of view-based dynamic design

A Method to Evaluate the Stimulation of a Real World Field of View by Means of a Spectroradiometric Analysis

Stimulation elicited by a real world field of view is related to the color, the intensity and the direction of the information reaching the eye: different spectral power distributions of light trigger different responses. An evaluation of the stimulation provided by the field of view can be performed by measuring the spectral radiance with a spectroradiometer and weighting this data with an efficiency curve. Different weights (physical, physiological and psychological) can lead to different analyses and consequently to different results. The proposed method allows an overall and simplified evaluation of the field of view based on spectral and luminance measures and a script that processes the luminous information. The final aim of this approach is to provide further information about the light stimulation reaching the retina and to supply a qualitative evaluation of the field of view, allowing to know how much stimulation is coming from a certain area within the visual field depending on the type of surface, basing on spectral and directional information. This approach can have practical implications, allowing technicians and designers to take into consideration the possible visual fields, in order to properly shape the features of stimulation throughout the day, hence following a field of view-based dynamic design

Approfondimento sperimentale sulla capacità delle nuove sorgenti di illuminazione artificiale di influenzare le performance, la qualità e la quantità del sonno

Negli ultimi anni la ricerca internazionale ha dimostrato che esiste una stretta relazione tra radiazione luminosa e ritmi circadiani, influenza del comportamento umano e stimolazione del funzionamento cerebrale; tali effetti non-visivi sembrano dipendere principalmente dall’intensità luminosa, dalla composizione spettrale, dalla durata dell’esposizione e dall’ora del giorno in cui essa avviene, ma ad oggi non sono ancora chiari gli effetti su specifiche funzioni cognitive, né si può considerare sufficientemente nota l’influenza delle nuova tecnologia LED. In quest’ambito, precedenti studi svolti dallo stesso gruppo hanno evidenziato che, rispetto all’illuminazione prodotta con sorgenti alogene, un’illuminazione LED con temperatura correlata di colore (CCT) neutra (4000K), produce effetti positivi su alcuni aspetti dell’attenzione, quali le funzioni esecutive e la vigilanza visiva: con l’illuminazione LED è stata riscontrata la capacità di produrre molteplici rappresentazioni mentali contemporaneamente e di incrementare il livello di vigilanza durante l’esecuzione di un compito di attenzione. La presente attività approfondisce gli studi svolti precedentemente considerando sorgenti con differente composizione spettrale e temperatura di colore: in un primo esperimento sono state confrontate le stesse lampade utilizzate nei lavori precedenti, alogene e LED neutro, ed in un secondo esperimento lo studio è stato ripetuto con due scenari luminosi LED, con temperatura correlata di colore calda (3000 K) e fredda (6800), per investigare la differente influenza che tali sorgenti hanno a livello psicofisiologico. In entrambi gli esperimenti sono stati analizzati sia gli effetti immediati sulle capacità attentive in un compito di vigilanza cross-modale, sia gli effetti conseguenti sul sonno. I risultati di questo studio mostrano un effetto positivo delle illuminazioni sperimentali (LED 4000 K e LED 6800 K) sulle prestazioni di vigilanza visiva, ma non sulla vigilanza acustica, se paragonato alle illuminazioni calde (alogena 2800 K e LED 3000 K), e l’assenza di effetti significativi dell’illuminazione, sia alogena sia LED, sul sonno dei soggetti partecipanti. La conoscenza approfondita dell’influenza che la luce ha sulla mente umana a livello cognitivo apre la strada ad una nuova tipologia di progettazione illuminotecnica, finalizzata tanto al comfort visivo quanto al benessere fisiologico e all’efficienza cognitiva

Urban lighting project for a small town: comparing citizens and authority benefits

The smart and resilient city evolves by slow procedures of mutation without radical changes, increasing the livability of its territory. The value of the city center in a Smart City can increase through urban lighting systems: its elements on the territory can collect and convey data to increase services to city users; the electrical system becomes the so-called Smart Grid. This paper presents a study of smart lighting for a small town, a touristic location inside a nature reserve on the Italian coast. Three different approaches have been proposed, from minimal to more invasive interventions, and their effect on the territory has been investigated. Based on street typology and its surroundings, the work analyzes the opportunity to introduce smart and useful services for the citizens starting from a retrofitting intervention. Smart city capabilities are examined, showing how it is possible to provide new services to the cities through ICT (Information and Communication Technology) without deep changes and simplifying the control of basic city functions. The results evidence an important impact on annual energy costs, suggesting smart grid planning not only for metropolis applications, but also in smaller towns, such as the examined one

Case study on economic return on investments for safety and emergency lighting in road tunnels

While planning a double-hole road tunnel with a length higher than one km, it is important to pay attention to the safety factor if an accident occurs. If there is a power outage, in order to avoid critical situations that could jeopardize the safety of the people present (facilitating the stream coming out from the tunnel and the arrival of the emergency personnel), it is really important to guarantee uninterrupted lighting of roadways, mandatory emergency lay-bys, and ways of escape. Uninterrupted service of the lighting systems supply must be guaranteed, in accordance with the current regulations, through the exertion of UPS (Uninterruptible Power Supply) and power units. During tunnel construction, such devices represent a cost that must be amortized. In this case study, which takes into consideration a section of a road tunnel characterized by emergency lay-bys and ways of escape, emergency and security lighting were planned and installation and management costs were evaluated. The goal of this research was the creation of a cash flow thanks to the energy generated by photovoltaic panels, in a way that the service life of the system (25 years) coincided with the amortization of the costs of the backup electrical equipment installation (complying with the regulations). The possibility of over-dimensioning the UPS and providing it with a proper photovoltaic panel surface (235 kWp) to generate and exchange electric energy with the grid was taken into consideration