Dipartimento di Ingegneria civile ed ambientale
Università degli Studi di Perugia

Costanza Borghesi                              

Thesis project title: Advancing High-Entropy to Thermochromic Oxides: Materials Engineering for Enhanced Passive Radiative Cooling Performance

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The dissertation proposes and discusses the features of novel materials, initially theoretically derived, for radiative cooling (RC) applications. This work represents the ideal trait d'union between material science and engineering problems, where, using an ab-initio parameter-free quantum mechanical approaches (exploiting standard available computational chemistry codes), the candidate has atomistically designed a class of compounds (so-called high entropy oxides, HEOs) that show particular efficiency in the mechanism of radiative cooling. Interestingly, as a result of the work, some of the precursors of these HEOs have been synthesized in the laboratory and tested in their RC performances, providing very encouraging results. In a parallel effort, the candidate has focused her attention on the analysis of vanadium dioxide as a candidate material for switchable radiative cooling. VO2 is a compound that is well-known in condensed matter for some of its unique features such as a characteristic phase transition between metallic and insulating phase that takes place at temperatures (MIT, metal-to-insulator transition temperature) slightly above room temperature (T~340 K) and that can be exploited to give rise to an on/off effect on the characteristics of the material itself and of any layers eventually coupled with the vanadia one. What the candidate did in his thesis work was to attempt to simulate with theoretical calculation approaches (the so-called DFT+U) the effect of doping/alloying on the possible modulation of the mentioned phase transition temperature towards room T, paying particular attention to the optical features of the two phases, metallic and insulating, of VO2

Nuno Miguel Da Conceicao Martins

Thesis project title: A CFD approach for fault detection in pressurized pipe systems by means of transient tests

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This research addresses the critical issue of faults in pressurised pipe systems, a pervasive concern across industries reliant on fluid transport. The study refines Computational Fluid Dynamics models to accurately simulate flow behaviour through discrete and extended partial blockages, validating results against experimental data. A key focus is the application to Transient Test-Based Techniques, an emerging non-invasive method for detecting and characterising partial blockages. By providing detailed insights into the fluid dynamics of these faults, the study contributes to improved detection methods and represents a significant advancement in understanding and managing pipe system anomalies. This investigation advances theoretical modelling in hydraulic transients while offering insights for practical application, yielding crucial tools for industry professionals and researchers. It deepens the understanding and management of complex fluid dynamics in faulty pipe systems, with potential applications spanning various sectors that depend on pressurised fluid transport, including but not limited to water distribution, petroleum, chemical processing, and industrial manufacturing., petroleum, chemical processing, and industrial manufacturing.

Francesco Cotana                                 

Thesis project title: Giuseppe Poggi architetto europeo.

Rilievo e analisi dell'opera del progettista nel contesto nazionale ed internazionale, con particolare riferimento all'architettura residenziale.

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Filippo Cornacchini

Thesis project title:  Digital ecosystems for public works and representative experiments in virtual environments

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Maria Eleonora Pipistrelli                           

Thesis project title: Probabilistic modelling and simulation of random materials

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This thesis presents a comprehensive framework for developing probabilistic models aimed at capturing the mechanical and morphological properties of random materials. The primary focus is on materials whose behavior is influenced by spatial configurations or size effects, particularly eco-friendly natural fibers and granular materials. The models developed in this research incorporate spatial variability, allowing for the simulation of virtual samples that closely reflect real-world measurements. A major contribution of this work lies in the calibration and validation of these probabilistic models using data from tensile tests and morphological studies on sustainable materials. The calibration process, a key focus often overlooked in the literature, ensures that the models accurately represent the variability inherent in natural materials. This research introduces a revised formulation of the Weakest Link Theory, accounting for correlation in the discrete model. Additionally, a continuous model is proposed for simulating the capacity of natural fibers. For granular materials, the study applies spherical harmonics (SH) analysis to shot-earth aggregates. The results highlight the versatility of these models, which can be extended to other random materials with similar characteristics. Ultimately, this work provides a robust, flexible framework for probabilistic modeling, offering valuable tools for simulating the performance of random materials in engineering applications.

Marco Parriani                         

Thesis project title: Caratterizzazione e reattività di specie ioniche ed eccitate con atomi, molecole e radicali di interesse ambientale

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The research activity in this doctoral project was mainly carried out at the Civil and Environmental Engineering department of the University of Perugia, Italy, and at the Physics department of the University of Gothenburg, Sweden, while the experimental collection of data took place at the Elettra Synchrotron Facility in Tri- este, Italy, at BESSY II at Helmholtz-Zentrum Berlin (HZB) and at PETRA III 3rd Generation Synchrotron Radiation Source at DESY, Hamburg. The research activity involved an active collaboration with national and international research groups (Prof. Raimund Feifel, University of Gothenburg, Prof. Stefano Stranges, University of Roma la Sapienza, Dr. Michele Alagia, CNR-IOM Institute) and in general with the research staff of the GasPhase and CiPo beamlines, that resulted in experiments on various gas-phase molecules. The research was also integrated into the activities of Raimund Feifel Physics group, at the University of Gothenburg, Sweden, with the collabora- tion resulted in several experiments performed at two different synchrotron facilities in Berlin and Hamburg. The collaboration with the GasPhase and CiPo staff of Elettra is a long-standing cooperation which aims at studying the electronic structure of iso- lated systems of increasing complexity such as atoms, molecules and clusters in the gas phase. The GasPhase and Circular Polarization beamlines of the Elettra storage ring cover a wide spectrum of advanced photoionization methods for a thorough de- scription of both energetics and dynamics of isolated systems. This doctoral thesis reports on a variety of experimental investigations aiming to advance the understand- ing of fundamental processes in molecules and clusters by exploiting the properties of synchrotron radiation: photoionization dynamics, double ionization, dissociation and molecular recognition were subject of investigation. The emphasis of the thesis lies on the application of advanced light sources in the study of photoionization processes in simple gas-phase molecules, with particular attention on systems that can be in- teresting in atmospheric physics and astrochemistry. Penning ionization, in particular regarding the formation of excited metastable species, as He* and Ne* by collisional excitation with energetic target particles (electrons, protons, or alpha particles, coming from the solar wind) and the possible subsequent chemi-ionization reactions (CHEMI) have been investigated. The double photoionization dynamics of various systems has been studied by the use of Photoelectron-Photoion-Photoion Coincidence spectroscopy using synchrotron radiation. Allene, a potential chirogenic molecule theorized to be present in the interstellar medium, showed for the first time four peculiar metastable species in the energy range investigated. Direct double ionization was studied for the nitrosyl chloride, a small reactive molecule of great atmospheric interest and the cyanoacetylene system, an interesting molecule that is part of the complex environ- ment of Titan, the largest moon of Saturn. The collaboration with the research group of Raimund Feifel lead to the investigation of the dissociation pathways of the main fragmentation channels of HNCS, of carbon diselenide, which can be regarded as the selenium analogue of the highly-symmetric carbon disulfide and carbon dioxide molecules, and of carbon suboxide, one of the stable members of the series of linear oxocarbons O=Cn=O, which also includes carbon dioxide and pentacarbon dioxide.

Francesco Casinini 

Thesis project title: Development of innovative data acquisition and transmission systems for diagnosis and control of water networks

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Arash Rahi

Thesis project title: Effect of hydroclimatic parameters on runoff generation under climate warming scenario

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 Jacopo Dari

Luciano Veritti

Thesis project title: Field experiments on the dynamic behaviour of automatic control valves in a real water supply system

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Water leakage management for Water Utilities is a significant challenge, impacting both service quality and financial losses. The economic implications of water losses are assuming greater importance, particularly within a framework of climate change characterized by recurrent droughts and water scarcity. Therefore, monitoring pipelines health through leakage control is crucial.  Facing the challenge of reducing leaks certainly involves detecting existing ones but also acting leakage control through proper devices and preventing those that might occur. In this perspective, automatic control valves (ACV) are extensively used in Water Distribution Networks (WDNs). Such devices allow to fix the downstream pressure at a given value, irrespective of the upstream value by automatically adjusting the opening degree. While automatic control valves (ACVs), particularly pressure reducing valves (PRVs), are widely used, their dynamic behaviour, especially during periods of rapidly changing flow conditions (e.g., during nighttime), has not been sufficiently explored in literature. This thesis investigates the dynamic behaviour of a PRV in a WDN supplying a coastal village near Trieste, Italy, where unexpected pressure variations have been linked to increased leakage. High frequency synchronized pressure monitoring is employed to identify the source of these transients. The study also includes an analysis of a needle valve, though the PRV investigation is prioritized due to the magnitude of potential overpressure and the difficulty of in-line valve testing. The thesis covers the water utility and supply system description, transient governing equations, needle valve analysis, PRV field measurements and analysis, and conclusions.

Mouad Rafai

Thesis project title: Energy geostructure for green buildings

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Desiree Muscas

Thesis project title: Integrating Urban Trees' Ecosystem Services into Sustainable City Planning with an Urban Metabolism Approach

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