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The paper presents a two-dimensional numerical investigation of a solar chimney combined with an absorbing capacity wall in a building’s south façade. The analysis was carried out in Aversa (Italy), in July and December, from sunrise to sunset. The chimney is made up of a converging channel, a vertical absorbing wall, and a two-degree angled glass plate. It is 5.0 m tall, while the height of the channel is 4.0 m, with an inlet of 0.34 m and an outlet portion of 0.20 m. A phase change material with metal foam makes up the thermal energy storage system. Four possible configurations are investigated to identify the ideal hybrid system arrangement in terms of thermal performance; the commercial code Ansys-Fluent is used to solve the problem. The results of the thermal energy storage system with metal foam and PCM are provided in terms of liquid fractions, stored energy, and stream function fields, while the ones of the wall temperature distributions in the channel are reported. Thermal and fluid dynamics behaviours are so evaluated to have some useful indications to improve the system.

In this work, a computational study on two-dimensional forced convection inside a volumetric solar collector based on a nanofluid with water and nanocarbon horns is carried out in steady state regime. A surface heat transfer from the upper wall of the solar collector toward the external ambient is present. The analysis is accomplished with governing equations assuming the single-phase flow model for the nanofluid mixture. The evaluation of heat transfer in the participating media due to the local absorption of nanoparticles is obtained employing the non-grey discrete ordinates method. The finite volume method is employed to find the solution and the simulations are obtained using ANSYS-FLUENT code. The analysis is accomplished to estimate the solar collector behaviors as a function of the inclination angle under different conditions in summer and winter regimes for residential use site in Aversa (Italy). The analysis allows to evaluate the thermal and fluid dynamic behaviors of the solar collector with an inclination angle from 0 to 90 degrees. Temperature and velocity profiles as well as temperature fields inside the channel are reported for different inclination angles, solar radiations and nanoparticle volumetric concentrations.

Background Chronic Obstructive Pulmonary Disease (COPD) encompasses various phenotypes that severely limit the applicability of precision respiratory medicine. The present investigation is aimed to assess the circadian rhythm of symptoms in pre-defined clinical COPD phenotypes and its association with health-related quality of life (HR-QoL), the quality of sleep and the level of depression/anxiety in each clinical phenotype. Methods The STORICO (NCT03105999) Italian observational prospective cohort study enrolled COPD subjects. A clinical diagnosis of either chronic bronchitis (CB), emphysema (EM) or mixed COPD-asthma (MCA) phenotype was made by clinicians at enrollment. Baseline early-morning, day-time and nocturnal symptoms (gathered via the Night-time, Morning and Day-time Symptoms of COPD questionnaire), HR-QoL (via the St. George’s Respiratory Questionnaire), anxiety and depression levels (via the Hospital Anxiety and Depression Scale), quality of sleep (via COPD and Asthma Sleep Impact Scale), physical activity (via the International Physical Activity Questionnaire) as well as lung function were recorded. Results 606 COPD subjects (age 71.4 ± 8.2 years, male 75.1%) were studied. 57.9, 35.5 5.3 and 1.3% of the sample belonged to the CB, EM, MCA and EM + CB phenotypes respectively. The vast majority of subjects reported early-morning and day-time symptoms (79.5 and 79.2% in the CB and 75.8 and 77.7% in the EM groups); the proportion suffering from night-time symptoms was higher in the CB than in the EM group (53.6% vs. 39.5%, p = 0.0016). In both CB and EM, indiscriminately, the presence of symptoms during the 24-h day was associated with poorer HR-QoL, worse quality of sleep and higher levels of anxiety/depression. Conclusions The findings highlight the primary classificatory role of nocturnal symptoms in COPD. Trial registration Trial registration number: NCT03105999, date of registration: 10th April 2017.

Immersion in forest environments was shown to produce beneficial effects to human health, in particular psychophysical relaxation, so much that this practice is increasingly recognized as a form of integrative medicine. Limited evidence exists about both statistical significance and size of the effects conditioned on personal characteristics, as well as on the main external variables. The primary purpose of this study was to substantiate the very concept of forest therapy by means of the quantification and significance of the psychological effects, stratified by gender, age groups and place of residence. A preliminary qualitative analysis of the main determinants, in particular the method of conducting, the meteorological comfort and the concentration of volatile organic compounds in the forest atmosphere, was afforded. Seven forest therapy sessions were performed in late summer though early fall, resulting in 150 psychological self-assessment questionnaires administered before and after each session. The results were comparable or even better than others reported in the international literature. Moreover, preliminary evidence arose about different functionality towards specific psychological indexes conditioned at least on gender and age groups, as well as meteorological comfort, structured programs and, possibly, volatile organic compounds showed an impact on the outcomes.

A numerical analysis on a two-dimensional steady state forced convection inside a solar collector with direct absorption due to a nanofluid composed of water and nanoparticles of carbon nanohorns is carried out. The analysis allows to provide the main fluid flow and thermal characteristics of a simple flat solar collector with a distance between the glass and the collecting plate of 1.2 mm and a length of 1.0 m. The solar collector presents heat losses from the upper wall towards the ambient by an external surface heat transfer coefficient. The governing flow equations for the nanofluid are written assuming the single-phase flow and the heat transfer due to the radiation, for the local absorption of nanoparticles, is evaluated by the non-grey discrete ordinates method. The carbon nanohorns optical and thermal properties are estimated by the data available in literature. The finite volume method is used to solve the problem and the results are carried out employing the ANSYS-FLUENT code. The results are given in terms of temperature and velocity fields and transversal profiles inside the channel for different values of mass flow rates, solar irradiance, volumetric nanoparticle concentrations and assigned values of external surface heat transfer coefficient and temperature.

Background A substantial increase in pulmonary and extra-pulmonary diseases due to non-tuberculous mycobacteria (NTM) has been documented worldwide, especially among subjects suffering from chronic respiratory diseases and immunocompromised patients. Many questions remain regarding the epidemiology of pulmonary disease due to NTM (NTM-PD) mainly because reporting of NTM-PD to health authorities is not mandated in several countries, including Italy. This manuscript describes the protocol of the first Italian registry of adult patients with respiratory infections caused by NTM (IRENE). Methods IRENE is an observational, multicenter, prospective, cohort study enrolling consecutive adult patients with either a NTM respiratory isolate or those with NTM-PD. A total of 41 centers, including mainly pulmonary and infectious disease departments, joined the registry so far. Adult patients with all of the following are included in the registry: 1) at least one positive culture for any NTM species from any respiratory sample; 2) at least one positive culture for NTM isolated in the year prior the enrolment and/or prescribed NTM treatment in the year prior the enrolment; 3) given consent to inclusion in the study. No exclusion criteria are applied to the study. Patients are managed according to standard operating procedures implemented in each IRENE clinical center. An online case report form has been developed to collect patients’ demographics, comorbidities, microbiological, laboratory, functional, radiological, clinical, treatment and outcome data at baseline and on an annual basis. An IRENE biobank has also been developed within the network and linked to the clinical data of the registry. Conclusions IRENE has been developed to inform the clinical and scientific community on the current management of adult patients with NTM respiratory infections in Italy and acts as a national network to increase the disease’s awareness. Trial registration Clinicaltrial.gov: NCT03339063.

Chronic obstructive pulmonary disease (COPD), lung cancer, asthma and pulmonary tuberculosis are common pulmonary diseases that are caused or worsened by tobacco smoking. Growing observational evidence suggests that symptoms and prognosis of these conditions improve upon smoking cessation. Despite increasing numbers of (small) randomised controlled trials suggesting intensive smoking cessation treatments work in people with pulmonary diseases many patients are not given specific advice on the benefits or referred for intensive cessation treatments and, therefore, continue smoking. This is a qualitative review regarding smoking cessation in patients with COPD and other pulmonary disorders, written by a group of European Respiratory Society experts. We describe the epidemiological links between smoking and pulmonary disorders, the evidence for benefits of stopping smoking, how best to assess tobacco dependence and what interventions currently work best to help pulmonary patients quit. Finally, we describe characteristics and management of any "hardcore" smoker who finds it difficult to quit with standard approaches. Copyright © ERS 2015.

International audience; A numerical investigation on a single slot jet impinging in a porous parallel-plate channel containing an air-saturated high permeability porous medium is accomplished. The wall opposite the slot jet is partially heated at uniform heat flux and the buoyancy effects are taken into account. The fluid flow is assumed two dimensional, laminar and steady. The porous medium is modeled using the Brinkman–Forchheimer-extended Darcy model and the Boussinesq approximation. The local thermal non-equilibrium (LTNE) hypothesis is invoked. The results are discussed in terms of streamlines, fluid and solid phase temperature fields, wall temperature profiles and local and average Nusselt numbers. The porous medium allows a more significant heat transfer close to the end of the heated part of the plate. For low Péclet numbers, forced flow and natural convection are opposite and the mean Nusselt number shows a decrease in heat transfer, whereas they are aiding for high Péclet numbers. Porosity effects on the mean Nusselt numbers were found weak.

The present paper analyses the evolution of renewable energy generation in the European Union through a decomposition analysis based on the Index Decomposition Analysis together with the Logarithmic Mean Divisia Index within the EU27 between 2000 and 2020. A four factors decomposition approach is considered for decomposing the total RES generation and a five factors model is employed to decompose the carbon emissions. Furthermore, a focus on wind and solar photovoltaic generation is introduced through a four factors decomposition calculated in the period 2010–2020. The most influential factors affecting the RES generation trend in the period 2000–2020 are the RES share and energy efficiency wich determined an increase of 1841 TWh and a decrease of 635 TWh respectively. Variations of carbon emissions are mostly affected by the energy intensity, namely the amount of energy necessary to produce one unit of GDP, which determined a reduction of 1040 Mt. Through the decomposition analysis, the paper successfully identifies the specific drivers supporting RES development and controlling carbon emissions, thus adequate policy measures can be designed to reach planned targets.

A numerical investigation on Latent Heat Thermal Energy Storage System (LHTESS), based on a phase change material (PCM) partially filled with metal foam, is accomplished. The geometry of the system is a vertical shell and tube LHTES made with two concentric aluminum tubes with the internal tube corrugated. The corrugated internal surface of the hollow cylinder is assumed at a constant temperature above the melting temperature of the PCM to simulate the heat transfer from a hot fluid. The other external surfaces are assumed adiabatic. The phase change of the PCM is modelled with the enthalpy porosity theory while the metal foam is considered as a porous media that obeys to the Darcy-Forchheimer law. Local thermal equilibrium (LTE) model is assumed to analyze the metal foam. Numerical simulations for PCM and PCM in the porous medium in LTE assumptions are obtained and their results are compared in terms of melting time, temperature fields and energy stored. The results show that the heat transfer in the LHTES system improves giving a very faster phase change process when the presence of metal foam increases.

The effects of metal foams on Latent Heat Thermal Energy Storage System, LHTESS, based on a phase change material, PCM, is numerically investigated. The geometry of the system is a vertical shell and tube LHTESS made of two concentric tubes. A constant temperature above the melting temperature of the PCM on the internal surface of the hollow cylinder is assumed to simulate the heat transfer from a hot fluid. The external surfaces are adiabatic. The PCM is completely embedded in the volume between the two coaxial cylinders. An aluminum metal foam is chosen, and it partially fills the volume starting from the internal cylinder. The enthalpy-porosity theory and the Darcy-Brinkman-extended model are employed to simulate, respectively, the phase change of the PCM and the metal foam which is modelled in local thermal equilibrium. Ansys-Fluent code is adopted to solve the governing equations. The results are rendered in terms of melting time, liquid fraction, temperature, and stored thermal energy as a function of time and for different metal foam thickness values. The results indicate that the melting time reduces with increase in the thickness of the metal foam. The partially filled thermal storage system exhibits varying characteristics at the initiation and at the sustenance periods of the heating process. A scale analysis is performed to estimate the melting time and the values are in tandem with the numerical model evaluation. (C) 2022 Elsevier Ltd. All rights reserved.

A viable solution to environmental problems related to pollutant emissions from internal combustion engine vehicles is electric cars. The main problem with electric vehicles, which also limits their widespread use, is due to lithium batteries and in particular their thermal control. Thermal control of lithium batteries is an extremely topical issue since it is not only related to the performance of the vehicles on which they are mounted, but also to the safety of the vehicles and drivers. For this purpose, both factors internal to the battery itself and external causes such as environmental conditions must be considered. In this work, a thermal control system based on metal foams partially filled by the phase change material (PCM) was numerically investigated as a possible application for cooling lithium batteries. For this purpose, a two-dimensional numerical model was constructed in which the PCM partially fills the metal foam. The finite volume method used through the ANSYS Fluent code was used for the governing equations, which are written assuming local thermal equilibrium. Several cases were simulated for different values of the external convective heat transfer coefficient. The results obtained, are reported in terms of temperatures and liquid fractions. Comparisons with partially filled and totally filled cases by PCM in the thermal control system are reported to show the advantage obtained, in terms of thermal control, with a composite system of metal foam and PCM.

A numerical investigation on foams in forced convection with Kelvin cell structure is carried out on water/Al2O3 nanofluids. The three-dimensional governing equations are written considering the single-phase model for the nanofluid. The analyzed foams have a porosity of ɛ = 0.95 and four different pore density values, with cells per inch (CPI) equal to 5, 10, 20 and 40, with assigned heat flux on the surface. The nanofluid velocity is in the range 0.003–0.1 m/s and the Reynolds number ranges from 0.6 to 5 × 102. It is observed that thermal development occurs first for the lowest velocities and for highest CPI values whereas the maximum temperature is obtained for the 5 CPI configuration and v = 0.003 m/s. Results show that the highest local entropy generation values are recorded near the points at higher temperature in correspondence with the inlet section and close to the geometric variation of the cells. The local entropy generation density reaches the maximum value at 40 CPI for the maximum velocity considered of 0.1 m/s. Global dimensionless entropy generation decreases for Reynolds number increases and the opposite is related to the dimensionless viscous entropy generation. Thermal dimensionless entropy generation is significantly greater than the dimensionless viscous entropy generation.