Journal of Aerosol Science最新文献

{"title":"Kinetic model of heterogeneous growth onto organic particles in supersaturated water environments","authors":"Xin Wang,&nbsp;Qi Zhang,&nbsp;Tong Zhang,&nbsp;Shoujie Yan,&nbsp;Lin Liu,&nbsp;Luying Yang","doi":"10.1016/j.jaerosci.2025.106541","DOIUrl":"10.1016/j.jaerosci.2025.106541","url":null,"abstract":"<div><div>Submicrometer organic particulate matter (PM2.5) is a significant pollutant in industrial environments that poses a severe threat to the product quality and physical wellbeing of production personnel. Water vapor phase transition is a particle growth mechanism through the nucleation of organic particles by a supersaturated steam field and the formation of droplet embryos in the active part of the particle surface, which promotes the growth of organic particles and reduces the suspended concentration of organic particles in the plant environment. This study establishes a kinetic model for the heterogeneous nucleation of submicrometer organic matter particles under water vapor conditions. Considering the particle surface roughness, condensation mechanism, and three-phase line long-force correction, the model introduces a correction of the orientation force of the droplet embryo on the surface of the organic particles. Using polyalphaolefin as a representative organic particle, this study investigated the influence of condensation mechanisms on the radius of droplet embryos, the effect of the saturation ratio on the radius of the droplet embryo, and variations in the nucleation barrier and nucleation rate. The results indicate that the kinetic model of organic particulate matter modified with orientation force exhibits a higher rate of liquid droplet embryo formation than conventional particle kinetic models. Furthermore, as the saturation ratio increases, the critical nucleation free energy decreases, rendering the nucleation barrier easier to overcome. A negative correlation exists between the nucleation rate and nucleation barrier, with an optimal value for the saturation ratio.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"185 ","pages":"Article 106541"},"PeriodicalIF":3.9,"publicationDate":"2025-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143102225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical properties of bare and coated soot aggregates probed by atomic force microscopy","authors":"Ashoka Karunarathne ,&nbsp;Egor V. Demidov ,&nbsp;Ali Hasani ,&nbsp;Alexei F. Khalizov","doi":"10.1016/j.jaerosci.2024.106523","DOIUrl":"10.1016/j.jaerosci.2024.106523","url":null,"abstract":"<div><div>Soot from incomplete combustion of carbonaceous materials is a major constituent of atmospheric aerosols. Individual soot particles are aggregates of primary carbon spherules connected together by carbon necks. Freshly released soot aggregates have lacey fractal morphology, but in the atmosphere they undergo compaction, induced by capillary forces exerted by liquid coatings that act against the covalent, cohesive and friction forces between the carbon spherules. Since compaction alters the optical properties and atmospheric lifetime of soot, an ability to model this process is important for predicting the soot’s environmental impacts. To inform and validate our recently developed discrete element method (DEM) model of a soot aggregate, we employed force spectroscopy by atomic force microscopy to measure the forces and other mechanical properties related to the bonding between the spherules in the individual soot aggregates. Fractal and compact aggregates, both bare and with liquid coatings were examined. We observed a characteristic sawtooth pattern on force–displacement curves and collected statistics on bonding forces within individual fractal aggregates, as they were fractured and unraveled. Contrary to fractal aggregates, compact aggregates could not be unraveled due to multiple cohesive interactions between spherules. An increase in bonding forces and energies due to capillarity was observed in coated aggregates. The sawtooth pattern was interpreted with the help of a simple conceptual model and the rigorous DEM model was used to show that only one or two necks need to be fractured for a fractal aggregate to yield, and that mechanical failure will most likely be in shear.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"185 ","pages":"Article 106523"},"PeriodicalIF":3.9,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143102219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A high performance differential mobility analyzer for the masses","authors":"Juan Fernandez de la Mora ,&nbsp;Jerzy Kozlovski","doi":"10.1016/j.jaerosci.2024.106522","DOIUrl":"10.1016/j.jaerosci.2024.106522","url":null,"abstract":"<div><div>A hand-held Differential Mobility Analyzer (DMA) weighting 4 kg is developed to operate laminarly at many hundreds of L/min, while covering at unusually high resolution the 1–200 nm size range. Coupled with a small and efficient portable vacuum cleaner pump requiring no cooling, a resolving power of 10 or more is obtained at mobility diameters above 1.4 nm. The resolving power at 200 nm is between 40 and 60. Certain design compromises have been made to enable the wide adoption of this instrument in conventional aerosol measurements, making it comparable to broadly used contemporary commercial DMAs in portability, complexity, and cost. Yet, the high flow rate capability provides drastic advantages in resolution, sensitivity and size range over more conventional DMAs. This DMA is nevertheless inferior in resolution to more specialized instruments developed for studies of either nanoparticles or viruses. The inner electrode is a 1° half-angle cone accelerating mildly the flow. Critical dimensions in mm are: outer radius R₂ = 19.58; inner radius at the outlet slit R₁ = 14.34; axial distance between slits L = 85.94.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"185 ","pages":"Article 106522"},"PeriodicalIF":3.9,"publicationDate":"2024-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143102201","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Size resolution and capillary centering in sheathed condensation particle counters studied with a new variable saturation condensation particle sizer","authors":"Juan Fernandez de la Mora ,&nbsp;Jerzy Kozlowski ,&nbsp;Michel Attoui ,&nbsp;Luis J. Perez-Lorenzo ,&nbsp;Francesco Carbone","doi":"10.1016/j.jaerosci.2024.106521","DOIUrl":"10.1016/j.jaerosci.2024.106521","url":null,"abstract":"<div><div>The variable-saturation condensation particle sizer (VSCPS) of Gallar et al. (2006) determines aerosol condensation (Kelvin) size distributions by measuring optically the concentration of grown particles, while quickly scanning over the saturation ratio. A time-varying yet spatially uniform saturation is achieved by injecting the aerosol with a capillary placed at the center of a larger flow of sheath gas, created by mixing variable proportions of a saturated and a dry flow. Prior studies with other VS CPSs with centered capillary injectors had shown excellent sizing resolution when scanning over the saturator or the condenser temperature. However, some VSCPSs exhibited poorer resolution. Using the VSCPS of Gallar et al. (2006) we observe here that a chief reason for resolution variability is an imperfect capillary centering. A new VSCPS design preserving an excellent centering upon assembling and disassembling is then tested, systematically achieving excellent resolution. We also widen the cross sections of the aerosol and the sheath flow at their merging region to reduce the corresponding Reynolds numbers, and hopefully maintain laminar flow at larger aerosol and sheath gas flow rates. This goal is also largely achieved, except at small aerosol flows, though at the cost of an increased response time.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"185 ","pages":"Article 106521"},"PeriodicalIF":3.9,"publicationDate":"2024-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143102198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tutorial: A photoacoustic spectrometer to measure aerosol light absorption","authors":"Prabhav Upadhyay ,&nbsp;Benjamin J. Sumlin ,&nbsp;Taveen S. Kapoor ,&nbsp;Lan Yang ,&nbsp;Rajan K. Chakrabarty","doi":"10.1016/j.jaerosci.2024.106518","DOIUrl":"10.1016/j.jaerosci.2024.106518","url":null,"abstract":"<div><div>Accurate measurement of aerosol light absorption is essential to reduce uncertainties associated with aerosol radiative forcing in climate models. Contemporary techniques to measure aerosol light absorption continue to suffer from systematic errors and biases that are difficult to quantify. Photoacoustic spectrometry offers a first-principles approach for <em>in-situ</em> measurement of aerosol light absorption. The photoacoustic effect takes place when particles are illuminated by an amplitude-modulated laser, whereupon the particles absorb some amount of incident laser beam energy. Most of the absorbed energy, typically, is released to the surrounding gas as heat, creating pressure waves (sound) of an intensity proportional to that of the modulated laser power. These pressure waves are detected using a sensitive acoustic sensor in real time. This tutorial outlines the working principle of a basic photoacoustic spectrometer (PAS) from a fundamental standpoint, and elucidates its construction by taking into consideration the different design constraints and optical configurations. Methods for data acquisition and signal processing are explained in detail. The tutorial concludes with a brief discussion on PAS calibration techniques, determination of the instrument’s limit of detection, and the intrinsic limitations of the technology.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"185 ","pages":"Article 106518"},"PeriodicalIF":3.9,"publicationDate":"2024-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143102202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancing electrostatic spray-painting efficiency with modified high-voltage conductors: A numerical study on pulsed electric fields","authors":"Amine Benmoussa ,&nbsp;Mohammad-Reza Pendar ,&nbsp;José Carlos Páscoa","doi":"10.1016/j.jaerosci.2024.106491","DOIUrl":"10.1016/j.jaerosci.2024.106491","url":null,"abstract":"<div><div>This study presents a numerical simulation of electrostatic spraying using a rotary bell sprayer equipped with a high-voltage control ring conductor. The effects of the electric field generated by constant and pulsed voltages at various frequencies applied to the electrostatic rotary bell sprayer (ERBS) with the control ring are explored. Using the OpenFOAM computational fluid dynamics framework, the simulations employ a three-dimensional Eulerian-Lagrangian method. The implemented algorithm models fully turbulent airflow using a Large Eddy Simulation (LES) approach, along with detailed modeling of spray dynamics, electric fields, and droplet tracking. The primary objective is to investigate the influence of different voltage application modes on the spraying process, with a focus on optimizing droplet consistency and control. The impacts of constant and pulsed voltages on spray plume formation, droplet volumes, and critical spraying stages are examined. Through in-depth analysis of electric field distributions, interface charge densities, and velocity fields, the complex interactions governing pulsed and constant voltage spraying processes are elucidated. The results show that pulsed voltage applied to the control ring shapes the spray plume and alters droplet behavior, though with limited effectiveness. In contrast, applying a pulsed voltage of −40 kV_rms to the sprayer’s body cup at frequencies of 800 Hz and 1600 Hz significantly improves spray characteristics, resulting in a modified torus shape and a narrower size range of larger droplets compared to constant voltage condition of −40 kV. This leads to a more uniform droplet size distribution, consistent paint film, and minimal overspray. Consequently, transfer efficiency (TE) increases by 6% at 800 Hz and 4.8% at 1600 Hz compared to constant voltage. This indicates that 800 Hz is the optimal frequency for applying pulsed fields, due to its notable effectiveness in improving deposition efficiency and minimizing material waste.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"184 ","pages":"Article 106491"},"PeriodicalIF":3.9,"publicationDate":"2024-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142748600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deposition behavior of a CuZr metallic glass particle on amorphous-crystalline composites","authors":"Nicolás Amigo","doi":"10.1016/j.jaerosci.2024.106492","DOIUrl":"10.1016/j.jaerosci.2024.106492","url":null,"abstract":"<div><div>This study investigates the deposition of a CuZr metallic glass particle on amorphous/crystalline composites through molecular dynamics simulations. The research reveals that increasing impact velocities lead to greater plastic deformation and disintegration of the projectile, with noticeable differences in substrate response based on crystalline layer thickness. Thicker crystalline layers enhance the substrate’s resistance to deformation, acting as effective barriers during impact. Additionally, the interactions between the amorphous matrix and crystalline phases are critical in determining mechanical behavior. These findings provide valuable insights into the performance of coatings, particularly for cold spray applications, highlighting the importance of optimizing layer properties to improve material durability.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"183 ","pages":"Article 106492"},"PeriodicalIF":3.9,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142720403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Novel quasi-static method to simulate collection efficiency and pressure drop of coalescing filters","authors":"Nishant Bhatta ,&nbsp;Sashank Gautam ,&nbsp;Amit Kumar ,&nbsp;Hooman V. Tafreshi ,&nbsp;Behnam Pourdeyhimi","doi":"10.1016/j.jaerosci.2024.106486","DOIUrl":"10.1016/j.jaerosci.2024.106486","url":null,"abstract":"<div><div>Coalescence filtration is the removal of dispersed droplets from a gas or from an immiscible liquid using a fibrous filter. Coalescing media are designed to capture the droplets, allow them to coalesce with one another and grow, and let them drain from the filter under gravity. Conducting numerical simulation to predict the pressure drop and collection efficiency of a coalescing filter is a computational challenge. The current paper presents a novel approach to simplify this highly transient multi-phase problem and to thereby propose a practical and expedited approach to design such filtration media. This was achieved by first developing a MATLAB code to perform Pore Morphology Method (PMM) simulations of fluid saturation in the filter and then by using the resulting 3-D saturation profiles in ANSYS (enhanced with a series of in-house subroutines) to conduct aerosol filtration simulations. Our simulations, interestingly, revealed that collection efficiency of a coalescing filter can decrease with increasing fluid saturation in the media, while its pressure drop can only increase. Our simulation results are analyzed in detail and are discussed in the context of prior studies reported in the literature.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"183 ","pages":"Article 106486"},"PeriodicalIF":3.9,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142659737","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dry powder inhaler deposition in the larynx and the risk of steroid inhaler laryngitis: A computational fluid dynamics study","authors":"Shamudra Dey ,&nbsp;Jonathan M. Bock ,&nbsp;Guilherme J.M. Garcia","doi":"10.1016/j.jaerosci.2024.106490","DOIUrl":"10.1016/j.jaerosci.2024.106490","url":null,"abstract":"<div><div>Dry Powder Inhalers (DPIs) are a mainstay in the treatment of obstructive respiratory diseases, including asthma and chronic obstructive pulmonary disease (COPD). Deposition of inhaled corticosteroids in the larynx elicits local side effects, potentially leading to steroid inhaler laryngitis. The objective of this study was to estimate the dose of DPIs that are deposited in the larynx relative to other regions of the respiratory tract using computational fluid dynamics (CFD). An anatomically accurate model of the airways (mouth to main bronchi) was constructed based on medical imaging of a healthy adult. Respiratory airflow and particle transport were simulated for constant inhalation rates of 30, 45, and 60 L/min. Two turbulence models were compared, namely the large eddy simulation (LES) and the <span><math><mrow><mi>k</mi><mo>−</mo><mi>ω</mi><mspace></mspace><mi>S</mi><mi>S</mi><mi>T</mi></mrow></math></span> models. DPIs were assumed to generate an aerosol cloud with a log-normal particle size distribution characterized by the mass median aerodynamic diameter (<span><math><mrow><msub><mi>d</mi><mn>50</mn></msub></mrow></math></span>) and geometric standard deviation (<span><math><mrow><msub><mi>σ</mi><mi>g</mi></msub></mrow></math></span>). We compared two commercial DPIs, namely DPI 1 had a large particle size (<span><math><mrow><msub><mi>d</mi><mn>50</mn></msub></mrow></math></span> = 50 μm, <span><math><mrow><msub><mi>σ</mi><mi>g</mi></msub><mo>=</mo><mn>2.55</mn></mrow></math></span>) and DPI 2 had a small particle size (<span><math><mrow><msub><mi>d</mi><mn>50</mn></msub></mrow></math></span> = 2 μm, <span><math><mrow><msub><mi>σ</mi><mi>g</mi></msub><mo>=</mo><mn>1.99</mn></mrow></math></span>). The laryngeal dose was 1.6-to-3.8-fold higher than the bronchial dose for DPI 1, while the laryngeal and bronchial doses (units of mass per unit surface area) were similar for DPI 2 for both turbulence models and all inhalation rates. The choice of turbulence model had little impact on the total extrathoracic deposition, but a significant impact on regional doses, with the LES model predicting higher larynx-to-bronchi relative doses than the <span><math><mrow><mi>k</mi><mo>−</mo><mi>ω</mi></mrow></math></span> model. Our prediction that the larynx is a hotspot for DPI deposition is consistent with the observation of laryngeal side effects in DPI users. Importantly, our simulations suggest that DPIs with larger particles (<span><math><mrow><msub><mi>d</mi><mn>50</mn></msub></mrow></math></span> = 50 μm) may increase the risk of steroid inhaler laryngitis.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"183 ","pages":"Article 106490"},"PeriodicalIF":3.9,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142704053","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dust resuspension from contaminated fabrics subjected to force-induced vibrations","authors":"Jie Feng ,&nbsp;Ka Chung Chan ,&nbsp;Chun-Ho Liu ,&nbsp;Christopher Y.H. Chao ,&nbsp;Sau Chung Fu","doi":"10.1016/j.jaerosci.2024.106489","DOIUrl":"10.1016/j.jaerosci.2024.106489","url":null,"abstract":"<div><div>A parametric study inspired by daily human activities (e.g., shaking clothes) is presented in this paper. Dust resuspension from contaminated fabrics (with four levels of initial dust load: 1, 10, 20, and 30 g/m²) subjected to force-induced vibrations (with low frequencies ranging from 0 to 6 Hz) was experimentally investigated. It was found that different settings of vibration duration, vibration frequency, and initial dust load can lead to significant differences in the resuspension results. Flexible fabric motion and multilayer dust motion were demonstrated as major contributors through visualization experiments. The observed phenomena of acceleration amplification effect along the fabric and various particle-particle interactions provided a crucial basis for our reasonable assumptions in the mathematical description. A set of empirical correlations was therefore developed whose form was proposed to be applicable in a wide range of scenarios involving moving surfaces. This paper not only reveals an everyday event that can trigger particulate matter emissions, but also helps enrich the understanding of particle dynamics.</div></div>","PeriodicalId":14880,"journal":{"name":"Journal of Aerosol Science","volume":"183 ","pages":"Article 106489"},"PeriodicalIF":3.9,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142704051","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}