Coupling of energy conversion systems and wellbore heat exchanger in a very deep oil well

The conventional geothermal power plants use the reinjection wells mostly to avoid the depletion of the geothermal reservoir gathering in the underground of the produced brine. Nevertheless, reinjection operations entail high economic costs and some risks. An alternative is the extraction of the heat without geothermal fluids production, the wellbore heat exchanger. The goal of the present paper is the analysis of the power production of the wellbore heat exchanger (WBHX) in time and the comparison between two different conversion systems of the thermal energy into electrical: the organic ranking cycle (ORC) plant and the Stirling motor. The selected case study is the oil field of Villafortuna Trecate, a medium enthalpy geothermal resource. The simulation results show a substantial decrease of the wellhead temperature in the first 6 months. After 1 year, the thermal power extracted with the WBHX is greater than 1.3 MW. The design parameters are 20 m3/h for the flow rate, outlet temperature 100.38 °C and the inlet temperature is 40 °C. The R-C318 has been selected as working fluid in the ORC plant: the net electrical power is 121 kW. The air is the working fluid in the Stirling motor: the evaluated net electrical power is 152 kW. The Stirling engine has an efficiency greater than 41 % compared to a system ORC

Experimental Study on the Effectiveness of Water Mist Extinguishing Systems for Protecting Paintings in Art Gallery Museums: Developing an Initial Methodological Model

Determining the input parameters for the calibration of a water mist extinguishing system in a compartment is important for the evaluation of the performance of the design. Although there is a lot of research on the use of water mist, it is still difficult understand the behavior of the system in terms of safety of people and protection of things. In this study, we aimed to conduct an experimental analysis to evaluate the effectiveness of water mist extinguishing systems in protecting paintings in art gallery museums. We compared onsite tests in a compartment of an art gallery and a numerical analysis carried out with Fire Dynamics Simulator (FDS). Numerical analysis using FDS included the water-cooling effect and the heat power in the simulated environment and the calibration for a model was found by reproducing the onsite results. The temperature trend was monitored as an essential parameter for the protection of the paintings. The study aimed to not only verify the effectiveness of the water mist system but also investigate the reproducibility of real-scale conditions through a simulated environment. The most important result obtained is the possibility of using a simulated environment instead of real-scale tests in order to test water mist capabilities

A Critical Review of Fire Tests and Safety Systems in Road Tunnels: Limitations and Open Points

Fire tests are used to determine whether fire protection products meet the minimum performance criteria set out in codes and legislation, as well as to certify these products. Experimental large-scale fires are used to test the performance of safety systems in tunnels, which are confined environments with a high probability of accidents and significant consequences due to the evolution of the event and whether there is the capability of counteracting it by safety measures. In this study, we conducted a systematic literature review following PRISMA guidelines. We searched the Scopus and Web of Science databases for publications from 2013 to 2022, resulting in a selection of 72 articles. An analysis was conducted on the following main topics: tunnel fires, fire characteristics (measured variables, spread, and smoke), model-scale tests, automatic shutdown systems, and ventilation solutions. One of the most important contributions of this study is the suggestion that fire tests represent an effective method not only to prevent fire events in tunnels but also to ensure the resilience of the infrastructure. Based on this state-of-the-art literature review, future tunnels could be designed by linking new smart technology and artificial intelligence to create interactive and high-performing safety systems

Progettazione e realizzazione di versioni evolute dei progetti di VirtualSquare basate sui nuovi servizi forniti dal kernel linux

La tesi si concentra sull'analisi e la realizzazione di metodi di interfacciamento a tecnologie presenti nelle moderne versioni del kernel linux. Queste tecnologie presentano interfacce talvolta troppo macchinose o troppo elementari, per questo motivo sono stati costruiti alcuni applicativi concentrandosi su aspetti di sicurezza e di usabilità. Saranno prese in esame le capability ambient, introdotte nel kernel linux versione 4.3 e i namespace. Questo porterà all'introduzione del pacchetto cado e del pacchetto nsutils: strumenti potenti per la gestione rispettivamente di capability ambiente e namespace linux di ogni tipo. I suddetti pacchetti sono stati inseriti all'interno del progetto VirtualSquare, team di sviluppo avente come obiettivo la realizzazione di applicativi open source legati al mondo della virtualizzazione. All'interno della tesi viene indicato uno scenario realizzabile con gli strumenti creati dal suddetto team. Verranno analizzati inoltre alcuni dettagli di sicurezza legati agli applicativi VirtualSquare già presenti. Infine sarà presentata un'analisi di sicurezza degli applicativi sviluppati, introducendo alcuni problemi d'esempio e la loro risoluzione. In conclusione saranno presentati alcuni sviluppi futuri del lavoro in esame

Dal cordoglio alla risoluzione del lutto

Sebbene i primi modelli teorici e le prime osservazioni descrittive risalgano agli inizi del Novecento, ad oggi il lutto rimane una condizione in fase di studio. In letteratura, il lutto normale è spiegato attraverso vari modelli teorici che si rifanno all’approccio psicoanalitico, a quello biologico, alla teoria della crisi o alla teoria esistenzialista, mentre il lutto complicato continua ad essere inserito nella categoria “condizioni che necessitano di ulteriori studi” del DSM-5 (APA, 2014). Il presente articolo ha lo scopo di fornire una panoramica il più esaustiva possibile sul tema del lutto: dalla definizione e descrizione dei principali modelli teorici alla clinica del lutto, sia nell’adulto che nel bambino - soffermandosi sulla distinzione tra lutto normale e lutto complicato secondo i criteri diagnostici attualmente in uso - ad una panoramica sui principali modelli di trattamento del lutto complicato nell’adulto e nel bambino

Occupational Risk Assessment in Landfills. Research Outcomes from Italy

Industrial production has brought increased wellbeing in the last years, but the amount of solid waste has undoubtedly increased. Thus, open dumpsites and landfills have been created throughout the world, with serious impacts on the environment and public health. In such a context, occupational health and safety (OHS) issues related to workers that have to deal with landfill characterization or management have not been considered sufficiently. To reduce such a research gap, in 2019 a research project started in Italy on OHS risk assessment in landfills. In fact, in such facilities, workers can be subjected to direct contact with the polluted environment and might not be completely aware of the entity and type of pollution (e.g., in open dumpsites). Starting with the analysis of INAIL data on accidents at work which occurred in Italy during the period 2008–2019, a specific risk analysis was carried out with the goal of defining risk determinants and profiles by means of K-means cluster analysis. Such an analysis allowed us to recognize the use of work equipment and the work environment as the main determinants of the accidents on the one hand, and the “driver of the excavator” as the most risky activity on the other. The achieved results take a step forward towards the characterization of occupational health and safety issues in landfills. Accordingly, the research outcomes represent a basis on which to address further research work in this field

Modified pseudo-elastic approach for modelling cyclic response of biological heart valves

A modified pseudo-elastic approach is proposed to model cyclic response on biological heart valves. The model takes into account hysteretic effects, in combination with hyperelastic anisotropic behaviour of valve leaflets, allowing reproduction of different loading and unloading paths. FEM implementation considered a biological heart valve during the closure phase

Risk-based tunnel design for consequences of road accidents. The role of tunnel lenght

Tunnel extension is an under-analysed variable in road tunnel accidents despite being a dimensioning parameter for the purposes of users’ safety according to Directive 2004/54/EC. Recent studies have shown a correlation between the tunnel length and consequences of accidents. The analysis of fire events which occurred in tunnels indicates that in many cases fires are triggered by road accidents. By analysing the road accidents in Italy, the study aims to assess the relative risk of accidents with serious consequences for different classes of road tunnels. The second objective was to assess, using a vehicle type (or size) approach, the corresponding probability of accidents involving vehicles or trucks and special vehicles resulting in serious consequences (domino effect). We analysed the Italian National Institute of Statistics (Istat) dataset on tunnel accidents which occurred between 2018 and 2020 on Italian public roads, involving at least one vehicle. Of these, we extracted tunnel accidents, classified by tunnel length and estimated the corresponding probability of serious consequences. The analysis identified 1,885 case studies of tunnel accidents that occurred in approximately 265 long tunnels and 450 short tunnels and underpasses. Compared with “controls”, “size” was found to be more than double in long tunnels where the related probability of serious accident consequences exceeded 50% more than those of short tunnels. We found that the related probability associated with serious accident consequences in tunnels over 500 m in length was higher than in short tunnels, except for trucks and special vehicles. Road accidents and research on risk evaluation of the effects associated with long and short tunnels are rare. The study aims to fill these gaps

Occupational road safety management. A preliminary insight for a landfill remediation site

Road crashes have been internationally recognized as one of the main causes of death. On one hand, in Europe, many governments are struggling with the ambitious target of zero road deaths by 2050. On the other hand, they are facing remediation of illegal waste dumps, subject to European infringement procedures and involving a lot of workers and heavy materials transportation. With the aim to further explore occupational health and safety (OHS) issues related to the remediation of such contaminated sites close to urban areas, we decided to focus our attention on road crashes involving people while working in the transport of materials and goods (i.e., occupational road safety). In the scientific literature, it is considered an emerging matter of concern, but no significant contribution nor specific procedures have been provided in this research field for workers in charge of contaminated sites. With the aim to fill such a gap, we decided to, first, investigate the impacts of a landfill remediation site (Malagrotta landfill, near Rome—Italy) on road safety in the surrounding context. Then, road safety management measures for workers driving heavy vehicles from and toward the reference site were suggested through the means of cluster analysis. The main road accident determinants (road safety signs and traffic conditions) for heavy vehicles in the Rome municipality, derived from a sample of 166 events, occurred in the period 2017–2021 on target road infrastructures for the case study. The events were finally grouped with a k-means three-centroid solution. Overall, despite the intrinsic limits related to the data’s details, this paper provides a specific and data-driven methodology to address occupational road safety near a landfill remediation site and encourages further research in this field

Green tunnel solutions. An overview of sustainability trends in the last decade (2013–2022)

In the last decade, green solutions for road tunnels have steadily emerged in the field of engineering. The focus has been on using renewable energy sources to conserve energy and address issues of disaster risk management, territorial resilience and vulnerability, especially as these issues relate to critical infrastructures (CIs), such as roads and railways. Focusing on the equilibrium of the infrastructure through integrated system services and their external effects guarantees a better evaluation of both effects as they relate to other systems and energy consumption optimisation. To this end, a systematic literature review has been conducted herein that collects and analyses studies carried out in the last decade that relate to green energy solutions in tunnels. Upon a review of the Scopus database from 2013 to 2022, 46 conceptual and empirical studies were selected. Classifications and discussions were then developed according to the main issues identified (e.g., energy saving in road tunnels, zero-energy tunnels, renewable energy sources, tunnel safety lighting, and sustainable infrastructure). Each contribution constitutes a part of the current literature that combines the problems of tunnel safety (as represented by the energy costs of safety devices, e.g., tunnel lighting systems) with issues of renewable energy sources in tunnels. The results of this systematic review offer ideas for future directions of the ‘green’ vision for tunnel infrastructure. This study represents the state-of-the-art of renewable energy solutions currently present worldwide. Gaps in the literature that have yet to be addressed include how to build a green system as well as how to balance its life costs. The review supports the claim that the integration of renewable energy sources can exploit innovative solutions related to the concept of resilience