bluuebunny/crossref_metadata_2025_split huggingface dataset:
Numerical performance investigation of High Vacuum Flat Plate Hybrid Photovoltaic-Thermal devices.
Authors: Strazzullo P , De Luca D , Caldarelli A , Gaudino E , Musto M , Gennaro Emiliano Di , Russo R 
Published: February 2024

Abstract
We propose an innovative flat plate hybrid Photovoltaic-Thermal system under high vacuum (HV PV-T) optimized for solar-to-thermal energy conversion. It consists of a glass cover, metallic vessel, and the actual PV-T device, which englobes a low-emissive Transparent Conductive Oxide (TCO), a perovskite-based PV cell, a Solar Absorber, and a copper substrate. We investigate, through a 1-D model developed in MATLAB, the performances of the proposed PV-T system, still mined by radiative losses, varying the operating temperature (Top) and the emittance of the TCO (εTCO
) in the ranges of (25÷175) °C and (0.05÷0.45) respectively. The annual thermal and electrical productions are evaluated considering the Typical Meteorological Year of Naples, Italy. Specific annual costs and emission savings are evaluated and compared with the ones assured by commercial High Vacuum Flat Plate Solar-Thermal (HVFP ST) and PV collectors. Results indicate that the proposed HV PV-T increases the annual cost savings by 34% and 11% when compared to HVFP ST and PV collectors, respectively. Moreover, the presented HV PV-T increases the annual CO2 emissions savings by 7% and 48% when compared to HVFP ST and PV collectors, respectively.
Thermally adaptive wall to enhance indoor comfort and energy performance
Authors: Bianchi F , Baldinelli G , Schnotale J A , Lechowska A A , Presciutti A 
Published: February 2024

Abstract
In the present work, a new environment-adaptive wall is proposed, based on an inside and outside radiant panel with pipes drowned on the panels themselves and hosting a heat-carrying liquid pushed by a pump. The purpose consists of transferring heat across the thickness of the wall, in the direction required for energy saving and enhancement of inner indoor thermal comfort. A Computational Fluid Dynamic (CFD) analysis is reported and the results are applied on a single zone box-shaped building, where a whole-year study is implemented by means of the transient simulation tool TRNSYS. The efficiency of this solution respect to the state-of the-art static walls is finally discussed. A concept of a laboratory setup of an adoptive wall along with first result are presented and discussed.
A new dry deposition model implemented in CALPUFF code to simulate contamination of radionuclides released into atmospheric environment post-nuclear accidental event
Authors: Giardina M , Buffa P , Cervone A , Lombardo C , Giaiotti D , Oshurok D , Skrynyk O 
Published: February 2024

Abstract
Long-range transport and deposition analyses of 137Cs following a hypothetical incident at Gösgen nuclear power plant are studied by using CALMET-CALPUFF model system. Comparisons are performed with results obtained from a version modified of CALPUFF using a new dry deposition velocity model. This model is based on a combination of aerodynamic resistances and considers local features of the mutual influence of inertial impact and turbulent processes. The results show that the modified CALPUFF code seems to be an appropriate tool for performing impact assessments on long-range transport in complex terrain contexts or to support preparedness and response capabilities for nuclear and radiological accidents.
Heat flux measurement approach for an enhanced thermometric method: preliminary tests
Authors: Evangelisti L , Barbaro L , De Cristo E , Guattari C , D’Orazio T , Asdrubali F , De Lieto Vollaro R 
Published: February 2024

Abstract
In situ tests are suitable to confirm the real thermal performance of building components, and several significant on-site measurement techniques have been studied in literature. However, among them the Thermometric (THM) method has been poorly examined by the scientific community, thus having opportunities for improvement, being a quite a new and non-standardized technique. The theory behind this technique is the Newton’s law of cooling and the main issue is associated to the heat transfer coefficient for which there is no agreement about the value to use. Here, a simple experimental apparatus characterized by a vertical heated sample, suitably thermally insulated was realized. Sensors were installed and direct heat flux measurements through a heat flux plate were performed and compared with (i) the heat flows obtained through the THM method (test conducted using the internal heat transfer coefficient recommended by the ISO 6946) and (ii) the heat fluxes obtained through the proposal of an enhanced THM method based on dimensionless groups analysis, thus requiring data processing based on convective and radiative components.
An overview of the Transient Hot Wire and preliminary studies for its implementation
Authors: Ricciu R , Congedo P M , Baglivo C , Baccoli R , Buonomo P L M , Mastino C C , Floris F , Cambuli F , Ostrogorsky A G 
Published: February 2024

Abstract
The opportunity to design a new portable system for measuring thermal conductivity in fluids arose from the need to measure the phase state (liquid and/or vapour). As is well known, thermal conductivity varies in relation to the phase state of the fluid. The Transient Hot Wire Method was used to measure thermal conductivity. First, the work includes innovations in the analytical model of heat transfer, progressing over time to contemporary numerical models used in standards. The applications in the bibliography span a wide range, including gases, liquids, and the latest advances in the field of nanofluids. Secondly, the study delves into the transient model of heat exchange, focusing on conduction. The authors used standardized correction equations for the prototype, ensuring accuracy and relevance. Finally, the work includes the design and construction of the transducer. This process begins with a Monte Carlo simulation, predicting the expected results. This simulation helps to define measurement system components based on their performance characteristics and in-depth analysis.
Retro-reflective plaster coatings after outdoor aging and soiling: an in-lab optical performance characterization
Authors: Di Giuseppe A , Pazzaglia A , Castellani B , Nicolini A , Rossi F , Cotana F 
Published: February 2024

Abstract
The potential benefits of highly reflective and retro-reflective (RR) materials on urban context have been performed by several studies through their optical characterization. During their lifetime, outdoor aging and soiling can affect the RR optical behaviour. To this aim, this study investigates the performance of RR plaster coatings after outdoor aging and soiling from May to October 2022 in Perugia, Italy. The same RR plaster coatings in pristine conditions were already characterized in lab in terms of optical performance. In particular, RR samples obtained by using glass beads with different diameters (i.e., 40 ÷ 70 μm and 70 ÷ 110 μm) distributed in three superficial density ranges (i.e., 0.30 ÷ 0.40 kg/m2, 0.20 ÷ 0.30 kg/m2 and 0.10 ÷ 0.20 kg/m2) have been investigated in this study through spectrophotometric and angular reflectivity analyses. In all cases, the post-aging RR samples exhibit lower global reflectance values with respect to the same RR samples in pristine condition. Concerning the angular reflection distribution analysis, a stronger relative RR component was found for the post-aging RR sample with an average diameter of 70 ÷ 110 µm and superficial density distribution equal to 0.10 ÷ 0.20 kg/m2 for each investigated incident direction.
Two Phase Bubble Columns: the Determinants of the Flow Regime Transitions
Authors: Varallo N , Besagni G , Mereu R , Inzoli F 
Published: February 2024

Abstract
The fluid dynamics in large-diameter bubble columns can be described by an analytical relation between two global flow parameters, the drift flux and the gas holdup. This relation, named bubble column operating curve, builds on five flow regime transitions. In order to determine the variables influencing the flow regime transitions, a statistical approach was derived by coupling: (1) the ordinary least squares method (OLS) to determine the relationship between the variables, (2) the variance inflation factor (VIF) to check for multicollinearity issues, and (3) the least absolute shrinkage and selection operator (LASSO), to select suitable variables. It was found that the geometrical characteristics of the sparger strongly influence the flow regime transitions, and uniform aeration is essential for all the regimes to exist. Increasing the superficial liquid velocity in the counter-current mode destabilises the mono-dispersed and poly-dispersed homogeneous flow regimes. As for the aspect ratio, an increase in the column aspect ratio slightly destabilises the existing flow regimes. The statistical method identifies viscosity as the only significative variable concerning the liquid phase properties.
Experimental data for flow boiling of R450A in a horizontal tube
Authors: Mastrullo R , Mauro A W , Passarelli A F , Viscardi I , Viscito L 
Published: February 2024

Abstract
According to the new European policies aimed at the replacement of highly-pollutant greenhouse gases refrigerants, the scientific community has focused on new synthetic environmentally friendly substances to be employed in vapor compression cycles for the refrigeration and the air conditioning fields.
On this regard, R450A is a new blend made up of R134a (42%) and R1234ze (58%), having a GWP equal to 604, and therefore represents an attractive solution as pure R134a substitute. In this paper, new flow boiling heat transfer and pressure drop data of R450A collected at the refrigeration lab of Federico II University of Naples are presented. The data refer to a horizontal stainless-steel tube having an internal diameter of 6.0 mm. The effects of mass flux (from 150 to 400 kg m−2s−1), heat flux (from 10 to 20 kW m−2) and saturation temperature (from 30 to 50 °C) are presented and discussed, together with the assessment of the most quoted two-phase heat transfer and pressure drop prediction methods.
The DEPLOY! Project: Development of a Deployable Pulsating Heat Pipe experiment on a parabolic flight
Authors: Billi A. , Perna R. , Picchi S. , Rosellini V. , Saltmarsh E. , Bocelli M. , Ricci N. , Miché N. , Bozzoli F. , Mameli M. , Filippeschi S. 
Published: February 2024

Abstract
DEPLOY! Project aims at analysing the behaviour of Deployable Pulsating Heat Pipe (PHP) shaped as a helicoidal torsional spring in the adiabatic section on board a Parabolic Flight platform. A PHP is a passive thermal control device where the heat is efficiently transported by means of the self-sustained oscillatory fluid motion driven by the phase change phenomena. The microgravity environment allows to eliminate the buoyancy force contribution in the liquid phase momentum. Consequently, it is possible to isolate the contribution of the pressure drop caused by the 3D arrangement and infer on their effect on the PHP performance. As a result, a proper design based on the previous considerations would increase the flexibility of the PHP for use in space applications without significant reductions in efficiency. The goal of DEPLOY! is to demonstrate the functionality of a Deployable Pulsating Heat Pipe in various unfolding configurations by analysing its thermal-hydraulic response throughout a Parabolic Flight. The presented Deployable PHP is composed of an aluminium tube (inner/outer diameters 1.6mm/2.6 mm) and filled with HFE-7000. It is heated at the evaporator using a flat heater and cooled at the condenser with a water-cooled cold plate. T-type thermocouples are used to measure the wall temperature in several locations, while two pressure transducers (one located in the evaporator section and another in the condenser section of the same pipe) measure the local fluid pressure. Additionally, an IR Camera will be used to observe a section of the pipe for further analysis of the flow frequency. The device operation will be tested on ground and 0-g at different heat loads (24W, 34W), in multiple static positions corresponding to different opening angles (0°, 45°, 90°, 135°, 180°) and during its dynamic opening from 0° to 180°, thanks to a remotely controllable motion system.
Estimation of Internal Heat Flux on Pulsating Heat Pipes using Kalman Filter: Numerical and Experimental Results
Authors: Margotto B H M , Colaço M J , Kopperschmidt C E P , Bozzoli F , Pagliarini L , Cattani L , da Silva W B , Hamada M , Nagano H 
Published: February 2024

Abstract
Pulsating Heat Pipes (PHPs) are two-phase passive thermal devices characterized by the presence of significant fluid oscillations inside the tubes that permit to fast and efficiently transfer heat from a hot region to a cold one. They are present in many engineering applications, e.g., electronics, sustainable energies, aerospace. They are very attractive due to their high heat removal capability, flexibility, and low manufacturing cost. Although they have been widely studied their working principles are still not fully understood. To better comprehend their thermal behaviour recent works presented different approaches to assess the internal heat flux in PHPs. However, all the adopted approaches are based on whole-domain techniques that require a higher computational cost compared with sequential estimations. Therefore, to allow heat flux estimation with lower computational effort, in this work a procedure based on the Kalman filter has been adopted. The heat flux has been estimated by solving the inverse heat conduction problem in the PHP’s wall adopting as input data the temperature measurement on the external surface of the pipe acquired by an infrared camera. Firstly, the procedure has been validated adopting synthetic data. Then, experimental data referring to actual operating conditions have been employed to estimate the internal heat flux. The Kalman filter has been adopted as technique to solve the classical instability intrinsically present in inverse problems. It is relatively simple to implement and requires only previous time information, requiring low computational costs. Moreover, the Kalman filter allows the real time estimation of the heat flux: assessing the heat flux on PHPs during operation could be a useful instrument to provide information about on-time working conditions and thus avoid any possible malfunctioning.
Numerical study of the Thermo-hydrodynamic behavior of a non-Newtonian nanofluid in a backward facing step
Authors: Mokhefi A. , Rossi di Schio E. , Valdiserri P. , Biserni C. , Derbal D. 
Published: February 2024

Abstract
In the present work, a numerical simulation of a laminar non-isothermal flow of a non-Newtonian nanofluid in a backward facing step (BFS) is presented. It deals with Cu-water nanofluid, where the mixture shows a shear thinning behavior flowing from the restricted part of the duct with a fully developed velocity and a cold temperature. The lower part of the extended area of the backward facing step is maintained at a hot temperature, while all the other boundaries are considered thermally insulated. Moreover, a uniform magnetic field according to different angle is applicated on the nanofluid flow. The numerical simulation is based on the resolution of the mass, momentum and energy balance equations using Comsol Multiphysics. The aim of the sensitivity study is to highlight the impact of the Reynolds number, the nanoparticles concentration, the Hartmann number and the angle of the magnetic field on the flow and the thermal behaviours, as well as on the Nusselt number. Surprisingly, the results show that an increase in the Hartmann number, corresponding to a more intense magnetic field, resulted in a significant reduction in flow intensity.
Analysis of discharge events in the CMS GE1/1 GEM
detectors in presence of LHC beam
Authors: Calzaferri S. ,   the CMS Muon Group
Published: February 2024

Abstract
In July 2022, the experiments installed on the Large Hadron Collider (LHC) accelerator ring started a new data taking phase, Run-3. Before this period, an upgrade campaign took place during the so called Long Shutdown 2 (2018–2022). In particular, the muon system of the CMS experiment has been upgraded with the installation of a new gas detector station, GE1/1, based on Gas Electron Multiplier technology (GEM). The CMS experiment has scheduled the installation of two additional GEM stations: GE2/1 and ME0. The aim of the GEM stations is to maintain the performance of the muon system, reached during the last data taking phase (Run-2), with the increase of instantaneous luminosity expected at the LHC. The installed GE1/1 station covers the pseudorapidity region 1.55 <|η|< 2.18. GE1/1 participated in the CMS Run-3 data taking from July to November 2022 and, in this period, its detectors were exposed for the first time to the radiation produced during the collisions of the LHC beams, with a center of mass energy of 13.6 TeV. Since the first days of Run-3, where only a few bunches collided in CMS, the GE1/1 detectors started to experience a significant number of discharges, affecting their smooth operation during the data taking. In this talk, we present an analysis of discharges, which started by simply counting the number of discharges occurring per detector. An interesting phenomenon observed was that the discharge rate can vary a lot among the installed detectors; this is due to the fact that the occurrence of discharges is driven by the manufacturing of the GEM foils used in the detectors. Imperfections in their manufacturing can lead to large variation in the discharge rate. In addition, the rate can vary in time, due to the fact that discharges can produce damage at the site generating them, deactivating a particular hole or, in the worst case, producing a short circuit in the GEM foil, deactivating a part of the foil amplification region. We present the evolution of the discharge rate in time and its dependence on the HV working point and on the luminosity delivered by the LHC beams. This contribution illustrates the actions taken to mitigate the discharge rate and to assure a smooth detector operation.
The XGIS instrument on-board THESEUS: detector principle and read-out electronics
Authors: Srivastava S. , Labanti C. , Amati L. , Campana R. , Virgilli E. , Marchesini E. , Borciani E. , Mele F. , Dedolli I. , Bertuccio G. , Demenev E. , Grassi M. , Malcovati P. 
Published: February 2024

Abstract
The functionality and experimental performance characterization of the latest four channel version of ORION ASIC, a very low noise multichip read out and processing electronics customized for the X and Gamma Imaging Spectrometer (XGIS) instrument onboard the Transient High-Energy Sky and Early Universe Surveyor (THESEUS) mission, is presented. XGIS is a set of two coded-masked wide field deep sky cameras using monolithic SDDs (Silicon Drift Detectors) and CsI:Tl (Thallium doped-Cesium Iodide) scintillator-based X-γ ray detectors. This paper highlights the design, working principle and the expected performances of the XGIS, on a small scale 2×2 prototype. Furthermore, the evolution timeline of different versions of ORION with detailed performance observations and analysis for spectroscopic resolution, electronic noise and the operational linear energy ranges of both X and the γ processors of the four-pixel ASIC version bonded to a 2×2 SDD array are emphasized. Each 2×2 SDD array element is electrically and dimensionally equivalent to single elements of the THESEUS 8×8 SDD array.
CaloScore v2: single-shot calorimeter shower simulation with diffusion models
Authors: Mikuni Vinicius , Nachman Benjamin 
Published: February 2024

Abstract
Diffusion generative models are promising alternatives for
fast surrogate models, producing high-fidelity physics
simulations. However, the generation time often requires an
expensive denoising process with hundreds of function evaluations,
restricting the current applicability of these models in a realistic
setting. In this work, we report updates on the CaloScore
architecture, detailing the changes in the diffusion process, which
produces higher quality samples, and the use of progressive
distillation, resulting in a diffusion model capable of generating
new samples with a single function evaluation. We demonstrate these
improvements using the Calorimeter Simulation Challenge 2022
dataset.
Accurate method based on data filtering for quantitative multi-element analysis of soils using CF-LIBS
Authors: HAN 韩 Weiwei 伟伟 , SUN 孙 Duixiong 对兄 , ZHANG 张 Guoding 国鼎 , DONG 董 Guanghui 光辉 , CUI 崔 Xiaona 小娜 , SHEN 申 Jincheng 金成 , WANG 王 Haoliang 浩亮 , ZHANG 张 Denghong 登红 , DONG 董 Chenzhong 晨钟 , SU 苏 Maogen 茂根 
Published: February 2024

Abstract
To obtain more stable spectral data for accurate quantitative analysis of multi-element, especially for the large-area in-situ elements detection of soils, we propose a method for a multi-element quantitative analysis of soils using calibration-free laser-induced breakdown spectroscopy (CF-LIBS) based on data filtering. In this study, we analyze a standard soil sample doped with two heavy metal elements, Cu and Cd, with a specific focus on the line of Cu I 324.75 nm for filtering the experimental data of multiple sample sets. Pre- and post- data filtering, the relative standard deviation for Cu decreased from 30% to 10%, The limits of detection (LOD) values for Cu and Cd decreased by 5% and 4%, respectively. Through CF-LIBS, a quantitative analysis was conducted to determine the relative content of elements in soils. Using Cu as a reference, the concentration of Cd was accurately calculated. The results show that post- data filtering, the average relative error of the Cd decreases from 11% to 5%, indicating the effectiveness of data filtering in improving the accuracy of quantitative analysis. Moreover, the content of Si, Fe and other elements can be accurately calculated using this method. To further correct the calculation, the results for Cd was used to provide a more precise calculation. This approach is of great importance for the large-area in-situ heavy metals and trace elements detection in soil, as well as for rapid and accurate quantitative analysis.