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In order to study the breakup and atomization mechanisms of the fuel-jet in air crossflow and realize the accurate and controllable atomization effect of fuel, this paper proposes a method by coupling the large eddy simulation method and the VOF to DPM method. The results show that the breakup and atomization of the fuel-jet are mainly caused by the Rayleigh–Taylor (R–T) unstable surface wave and the Kelvin–Helmholtz (K–H) instability. The density of fuel-particles is higher near the central region of the fuel jet trajectory, decreasing as distance from the central region increases. As the momentum ratio increases, the penetration depth of the fuel-jet column also increases, resulting in a more concentrated spatial distribution of fuel particles. Conversely, with a lower momentum ratio, the spatial distribution of fuel particles becomes more uniform. For the spatial distribution of fuel particles, a new mathematical model is established to characterize the spatial distribution boundary of fuel particles. At the same momentum ratio, the higher the air velocity, the smaller the average particle diameter. At the same Weg number, the higher the fuel-jet velocity, the higher the average particle diameter. The relative error of the average particle diameter between the experiment and numerical simulation is very small, which is 6.4%. [ABSTRACT FROM AUTHOR]

Electrospray (ES) has attracted significant interest due to its advantages in generating uniform droplets and enabling controlled deposition. However, the complex interactions and droplet motion mechanisms between fluids and electric fields are still not well understood. Herein, this study presents a three-dimensional numerical model based on the volume of fluid and Lagrangian approaches to simulate the ES process in the pulsed jet mode. The model accurately captures the morphology and the atomization characteristics in the pulsed jet mode of ES. The effects of voltage and Reynolds number on the length of the non-atomized zone (including quasi-static Taylor cone, transition zone, and jet), diameter of the jet breakup, and atomization characteristics are discussed. Also, the mechanism of atomized droplets is revealed by analyzing the magnitudes of different types of forces imposing on the droplets in the electric field. The results indicate that higher Reynolds numbers lead to increased length of non-atomized zone and diameter of jet breakup, while the elevated voltages enhance atomization. Electric and Coulomb forces are, respectively, the dominant forces of forming the jet and expanding the atomization angle. Coulomb force increases the atomization angle, and electric field force increases the velocity of atomized droplets. Gravity and drag-force effects are relatively negligible throughout the atomization process. These findings contribute to a better understanding of the electrospray mechanisms and provide insights for optimizing electrospray applications. [ABSTRACT FROM AUTHOR]

In the field of preparation of cerium oxide by Venturi jet pyrolysis reactor, the spray pyrolysis process can achieve energy saving and environmental protection. The atomization effect of transverse air flow on the droplet directly affects the morphology of the product, and this research can improve the high value of cerium oxide applications. In this paper, a novel Venturi jet pyrolysis reactor has been developed. The atomization stage in the preparation process was studied by combining experiment and numerical simulation. The results show that the entire atomization process can be divided into primary atomization and secondary atomization. The primary atomization process of the liquid jet consists of columnar fragmentation and surface fragmentation, which are dominated by Rayleigh–Taylor (R-T) instability and Kelvin–Helmholtz (K-H) instability respectively. In the process of atomization of liquid column, the increase in gas velocity helps to promote the atomization. The Sauter mean Diameter value at 35 and 40 m/s gas velocity is the smallest, and the atomization effect of Venturi reactor is the best. With the increase in Weissenberg number (Wi), the crushing mode of droplets in Venturi reactor gradually changes from envelope to envelope—core and further evolves into core-layer. The core-layer crushing effect is the best, and the distribution range of daughter droplets is larger. The crushing state of atomized droplets in Venturi reactor is summarized. When Wi < 12, it is vibration crushing; when 12 < Wi < 30, it is packet crushing; when 30 < Wi < 45; it is pack-core crushing; and when 45 < Wi < 75, it is stamen-layer breakage. [ABSTRACT FROM AUTHOR]

Utilizing magnesium chloride (MgCl2) in the ammonia method to prepare magnesium hydroxide (MH) flame retardant products holds significant importance. This study introduces a novel approach for MH preparation, leveraging atomization technology to enhance the ammonia method. An experimental device for atomization-enhanced MH synthesis was developed. Atomization technology alters the reaction scale of the original reactor, generating microscale droplets that diminish the macroscopic reaction scale to the microscale. Computational fluid dynamics simulations demonstrate that adjusting gas and liquid supply pressures effectively enhances atomization performance. Optimal atomization is achieved at a gas supply pressure of 0.3 MPa and liquid supply flow rate of 60 l/h, producing micrometer-level droplets. Experimental results reveal sharp x-ray diffraction diffraction peaks in the transformed MH product, exhibiting a smooth substrate, high intensity, absence of impurities, and high purity. The MH conversion rate peaks at 76.2%. This study pioneers a novel avenue for future nanomaterial reactor development. [ABSTRACT FROM AUTHOR]

This study investigated the impact of varying atomization amounts on composite machining involving both atomized electrical discharge ablation machining and electrochemical machining (EDAM-ECM). Additionally, this study examined the effects of different atomization amounts on the material removal rate, relative electrode wear rate, processing waveforms, surface roughness, surface morphology and elements, and the EDAM-to-ECM ratio. Moreover, a theoretical model for describing the material removal process in composite processing was developed. Furthermore, the effect of the ECM ratio on the processing results was quantitatively analyzed through the integration of statistical circuits with a formula for calculating recast layer thickness. The model was used to predict and select the optimal atomization amounts required to achieve recast layer removal during processing. The results revealed that at an atomization amount of 200 mL/min, 16.7% of the total material removal was attributable to ECM, indicating the successful removal of the recast layer. At this atomization amount, the fabricated sample maintained a machining precision of 0.02 mm. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Computational Mechanics / Jisuan Lixue Xuebao is the property of Chinese Journal of Computational Mechanics Editorial Office, Dalian University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study presents an improved comprehensive atomization model for a pressure swirl atomizer. The model integrates internal flow predictions, linear instability analysis of a swirling annular liquid sheet, primary atomization sub-model, and droplet velocity sub-model. Measurement data combined with the inviscid theory model predict the internal flow, providing liquid sheet velocity and thickness at the atomizer outlet. The dispersion relation of surface disturbances is obtained through linear instability analysis. A primary breakup predictive model for particle size distribution is constructed based on the wavelength and growth rate within the full unstable wavenumber range of the dispersion relation. Assuming uniform circumferential distribution and a normal distribution of spray angles, the droplet velocity is assigned according to the liquid sheet velocity. The model is implemented into Eulerian–Lagrangian simulations as initial conditions for discrete phase droplets to simulate the spray field. Results show the model can accurately predict the Sauter mean diameter with an error of less than 6% and effectively predicts the spray structure and spray cone angle. The dependency of the model on its parameters is also studied, determining that the values of the ligament constant and dispersion angle have an obvious impact on the prediction of Sauter mean diameter and spray structure. [ABSTRACT FROM AUTHOR]

Copyright of Advances in New & Renewable Energy is the property of Editorial Office of Advances in New & Renewable Energy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In heat engines utilizing fuel injection, the processes of atomization and spray formation have a significant impact on the combustion process, thereby determining both efficiency and emission characteristics. Accurate prediction and control of spray formation in fuel injection systems play a key role in improving the efficiency and environmental performance of thermal engines, especially with the emergence of carbon-neutral fuels. To achieve accurate prediction of spray mixture formation, it is imperative to refine the atomization model for the liquid jet within numerical simulations. This requires a phenomenological representation of the atomization process that avoids reliance on computational constants obtained from spray experimental results. Consequently, the present study attempts to mathematically model the turbulent nozzle flow and liquid jet atomization process, leading to the development of a novel primary breakup model. The construction of the primary breakup model involves an analysis of the turbulence at the nozzle inlet. By merging this turbulence with the turbulence resulting from wall shear flow within the nozzle, the model provides insight into the internal turbulence and surface instability of the liquid jet, encompassing the turbulence spectrum. Consequently, the influence of nozzle length on the turbulent flow within the nozzle can be understood, and the droplet formation characteristics of the liquid jet can be predicted along with its multi-wavelength dispersion characteristics. The model effectively captures the experimental results in terms of breakup length and droplet dispersion characteristics, thus adding a higher level of accuracy to numerical simulations. Ultimately, the in-depth study of this model, coupled with its comparison with experimental results, enhances the understanding of the liquid jet atomization process. [ABSTRACT FROM AUTHOR]

This article reports the design and experiment of a novel air-assisted nozzle for pesticide application in orchard. A novel air-assisted nozzle was designed based on the transverse jet atomization pattern. This article conducted the performance and deposition experiments and established the mathematical model of volume median diameter (D50) and liquid flow rate with the nozzle design parameters. The D50 of this air-assisted nozzle ranged from 52.45 mmto 113.67 mm, and the liquid flow rate ranged from 142.6 ml/min to 1,607.8 ml/min within the designed conditions. These performances meet the low-volume and ultra-low-volume pesticide application in orchard. The droplet deposition experiment results demonstrated that the droplet coverage distribution in different layers and columns is relatively uniform, and the predicted value of spray penetration (SP) numbers SPiA, SPiB, and SPiC (i =1,2,and3)are approximately 70%, 60%, and 70%, respectively. The droplet deposits on the foliage of the canopy (inside and outside) uniformly bring benefit for plant protection and pesticide saving. Compared with the traditional air-assisted nozzle that adopts a coaxial flow atomization pattern, the atomization efficiency of this air-assisted nozzle is higher. Moreover, the nozzle air pressure and liquid flow rate are considerably lower and greater than the traditional air-assisted nozzle, and these results proved that this air-assisted nozzle has great potential in orchard pesticide application. The relationship between the D50 and nozzle liquid pressure of this air-assisted nozzle differs from that of traditional air-assisted nozzles due to the atomization pattern and process. While this article provides an explanation for this relationship, further study about the atomization process and mechanism is needed so as to improve the performance. [ABSTRACT FROM AUTHOR]

Salt particles generated by aerosol generator are commonly used in air filtration test. As a common phenomenon, the number of generated particles increases with the salt concentration in the atomization solution. Thus far, the dependence of the particle number on the concentration of the atomization solution is not fully understood. In this study, two hypotheses were proposed to explain this phenomenon: i) a single droplet generates multiple solid particles, and the generated particle number is influenced by the salt concentration, and ii) the original droplet number increases with an increase in the salt concentration of the atomization solution. By observing the particle formation process of the levitated millimeter-scale NaCl droplet, one droplet was found to generate one particle in free air. However, whether these results are applicable to micrometer-scale droplets remains to be determined. In situ measurements were performed to detect the size distributions of the original droplets generated by the atomization solutions with various salt concentrations. A more concentrated atomization solution induced a higher number of original droplets. Particle formation patterns of droplets on glass substrates and filaments were demonstrated. Traditional observation methods for droplet drying are unsuitable for studying the particle formation of atomized droplets because of the large difference in droplet size and the existence of external forces. [ABSTRACT FROM AUTHOR]

Based on industrial atomization devices, the efficiency of atomization and fumigation has been improved through hardware and software modifications and process design of atomization and fumigation equipment. By adding three sets of medicine and fumigant boxes and introducing a high-pressure atomization machine and an ultramicro-atomization nozzle, the diversity of the atomization and fumigation options was increased and the automatic proportioning of fumigants (ratio ranges of 1:1-1:200) was achieved. The optimal pressure of the high-pressure atomization machine 5.0 MPa, whereas the optimal mode was intermittent atomization for 75 s when an acrylic fumigation box was used. In a storage warehouse of 550 m3, the optimal pressure for the high-pressure atomization machine was 6.5 MPa, whereas the optimal operation mode was continuous atomization for 7 min, followed by natural precipitation of the fumigant natural for 3 min. The ultramicro-atomization nozzles were installed at 1 m intervals and the placement area of the specimens for atomization and fumigation were located 50 cm away from the wall of the warehouse and vertically 0.5~1.0 m below the ultramicro-atomization nozzles. Fumigation treatment with 40 mmol/L salicylate (SA) was effective in maintaining the storage quality of 'Xiaobai' and 'Saimaiti' apricots. At the end of the 7 day storage period, firmness of 'Xiaobai' apricots was 8.72 N, whereas the soluble solids (TSS) and titratable acid (TA) contents were 15.9% and 0.49%, respectively, representing 1.66-, 1.10-, and 1.58-fold increase compared to those of the control group, respectively. The decay rate was 0 after treatment with 40 mmol/L SA. The firmness of the Saimaiti apricots was 9.01 N, whereas TSS and TA contents were 13.5% and 0.67%, respectively (1.57-, 1.69-, and 1.60-fold higher than those of the control group, respectively). The decay rate was also 0 for Saimaiti apricots fumigated using SA. These results provide insights and technical support for the application of atomization and fumigation technologies in the storage and preservation of fresh apricots. [ABSTRACT FROM AUTHOR]

Coal mine acid drainage is a type of industrial wastewater generated in the process of coal production and utilization that has a low pH and contains a small amount of organic matter and SO42−, which is harmful to the environment. The ·OH scavenger was used to optimize the grounded electrode atomized corona discharge (GEACD) technology for the treatment of coal mine acidic wastewater. The effects of various factors on the discharge effect were investigated, and the optimal operating scheme for the subsequent test was determined as 35 mm distance between barrel electrodes, 0.6 mm diameter of wire electrodes, and a flow rate of 45 mL/min. The effects of discharge voltage, discharge time, and ·OH scavenger on COD removal rate and pH in coal mine acid drainage were also investigated. The results showed that at the optimum discharge voltage of 12 kV, discharge time of 66 min, and SO42− to ethanol concentration ratio of 1, the COD value decreased from 152.84 mg/L to 43.27 mg/L, and the pH value increased from 5.6 to 6.1. [ABSTRACT FROM AUTHOR]

Copyright of Revista Nutrición Clínica y Dietética Hospitalaria is the property of Sociedad Espanola de Dietetica y Ciencias de la Alimentacion and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Atomization is a treatment method to make inhaled liquids into aerosols and transport them to target organs in the form of fog or smoke. It has the advantages of improving the bioavailability of drugs, being painless, and non-invasive, and is now widely used in the treatment of lung and oral lesions. Aerosol inhalation as the route of administration of therapeutic proteins holds significant promise due to its ability to achieve high bioavailability in non-invasive pathways. Currently, a great number of therapeutic proteins such as alpha-1 antitrypsin and Dornase alfa are effective. Recombinant humanized collagen type III (rhCol III) as a therapeutic protein is widely used in the biomedical field, but atomization is not a common route of administration for rhCol III, presenting great potential for development. However, the structural stability of recombinant humanized collagen after atomization needs further investigation. This study demonstrated that the rhCol III subjected to atomization through compressed air had retained its original molecular weights, triple helical structures, and the ability to promote cell adhesion. In other words, the rhCol III can maintain its stability after undergoing atomization. Although more research is required to determine the efficacy and safety of the rhCol III after atomization, this study can lay the groundwork for future research. [ABSTRACT FROM AUTHOR]

The encapsulation of β-carotene was investigated using pullulan and whey protein isolate (WPI) as a composite matrix at a weight ratio of 20:80, employing both spray-drying and freeze-drying techniques. The influence of processing parameters such as the concentration of wall material, flow rate, and inlet temperature for SP encapsulants, as well as wall-material concentration for FZ encapsulants, was examined in terms of encapsulation efficiency (EE). The morphology, structural characterization, moisture sorption isotherms, and thermal properties of the resulting encapsulants at optimum conditions were determined. Their stability was investigated under various levels of water activity, temperature conditions, and exposure to UV–Vis irradiation. β-carotene was efficiently encapsulated within SP and FZ structures, resulting in EE of approximately 85% and 70%, respectively. The degradation kinetics of β-carotene in both structures followed a first-order reaction model, with the highest rate constants (0.0128 day−1 for SP and 0.165 day−1 for FZ) occurring at an intermediate water-activity level (aw = 0.53) across all storage temperatures. The photostability tests showed that SP encapsulants extended β-carotene's half-life to 336.02 h, compared with 102.44 h for FZ encapsulants, under UV–Vis irradiation. These findings highlight the potential of SP encapsulants for applications in functional foods, pharmaceuticals, and carotenoid supplements. [ABSTRACT FROM AUTHOR]

Immunoglobulin G (IgG) is an antibody used in numerous therapeutic indications. For this reason, high-purity IgG is required, which implies the use of selective adsorption chromatographic purification techniques. Although, before using chromatography, it is highly important to study the interaction between IgG and the adsorbent. Due to its characteristics, biopolymeric adsorbents are widely studied. However, there are no studies in the literature that evaluate IgG adsorption onto fibroin, a natural polymer that can be used as an ion exchange adsorbent. Thus, the aim of this work was to evaluate the adsorption of human IgG on fibroin microparticles. The microparticles were prepared from fibroin solution using the atomization method, with an average diameter of 108.5 μm. Three buffers (MOPS, MES and Tris–HCl), with different pH, were used, and for the best conditions, the influence of ionic strength (NaCl from 0 to 1 mol L−1), temperature (4 °C to 37 °C) and rotation (20 rpm to 40 rpm) were studied. The highest adsorption capacity (906.45 mg g−1) was reached with the MOPS buffer at pH 8.0, without NaCl, 25 °C and 30 rpm, which is higher than typical adsorption capacities found in the literature for other adsorbents. The adsorption capacity reduced with increasing temperature from 25 °C to 37 °C and rotation rate from 30 to 40 rpm. The thermodynamic parameters demonstrated that adsorption is spontaneous and endothermic. These results open up new possibilities of application of fibroin microparticles, considering the medium in which they are inserted, and highlights the improvement of IgG chromatographic purification for uses in pharmaceutical field. [ABSTRACT FROM AUTHOR]

An increased demand for natural products nowadays most specifically probiotics (PROs) is evident since it comes in conjunction with beneficial health effects for consumers. In this regard, it is well known that encapsulation could positively affect the PROs' viability throughout food manufacturing and long-term storage. This paper aims to analyze and review various double/multilayer strategies for encapsulation of PROs. Double-layer encapsulation of PROs by electrohydrodynamic atomization or electrospraying technology has been reported along with layer-by-layer assembly and water-in-oil-in-water (W1/O/W2) double emulsions to produce multilayer PROs-loaded carriers. Finally, their applications in food products are presented. The resistance and viability of loaded PROs to mechanical damage, during gastrointestinal transit and shelf life of these trapping systems, are also described. The PROs encapsulation in double- and multiple-layer coatings combined with other technologies can be examined to increase the opportunities for new functional products with amended functionalities opening a novel horizon in food technology. [ABSTRACT FROM AUTHOR]

The combustor employed in small and medium-sized turboshaft engines is characterized by a small flame tube height and a large distance between adjacent burners, rendering it challenging to ignition. Moreover, the process of spray ignition exhibits complexity and needs further investigation. This study will delve into the performances of spray atomization and spark ignition within an annular combustor. Our objective is to thoroughly elucidate the interplay among atomization characteristics and flame propagation, seeking to shed some light on the fundamental mechanisms underlying flame dynamics from the perspective of timescales during the light-round processes. Planar Mie scattering and high-speed imaging technologies are employed to capture droplet distribution and time-resolved flame images, respectively. We have developed an algorithm capable of precisely tracking the flame front, enabling us to map out the trajectories of flame propagation. An analysis of transient flames reveals that the movement of leading points can be elucidated by the characteristics of the flow field and the distribution of the spray. It is demonstrated that the velocity of the flame front is affected by factors such as the pressure drop, equivalence ratio, and the distance between adjacent burners. Through an analysis of numerous spark events, this work identifies three distinctive flame propagation patterns: swirling-entrainment, archlike-entrainment, and another archlike-entrainment pattern. It is noted that these patterns exhibit variations by alterations in pressure drop and equivalence ratio. [ABSTRACT FROM AUTHOR]

In this work, we experimentally and numerically investigate cavitation bubble dynamics in a thin liquid layer surrounded by gas. We focus on configurations featuring strongly confined bubbles at dimensionless bubble-free surface stand-off distances D * below unity. Additionally, we impose the condition of null Kelvin impulse, subjecting a bubble to the oppositely equal influence of two opposing free surfaces, resulting in the formation of two convergent water jets. We observe a diverse spectrum of jetting phenomena, including broad jets, mushroom-capped jets, and cylindrical jets. These jets become progressively thinner and faster with lower D * values, reaching radii as small as 3% of the maximal bubble radius and speeds up to 150 m/s. Numerical results reveal a linear relationship between the jet impact velocity and the local curvature at the bubble region proximal to the free surface. This suggests that the magnitude of bubble deformation during its growth phase is the primary factor influencing the observed fivefold increase in the jet impact velocity in the parameter space considered. Our findings show that bubble collapse intensity is progressively dampened with increased confinement of its environment. As D * decreases beyond a critical value, the liquid layer separating the bubble and ambient air thins, leading to the onset of interfacial shape instabilities, its breakdown, and bubble atomization. Furthermore, we compare bubbles at zero Kelvin impulse to corresponding anisotropic scenarios with a single free surface, revealing that the dynamics of axial jets until the time of impact is primarily influenced by the proximal free surface. The impact of convergent axial jets at null Kelvin impulse results in local pressure transients up to 100 MPa and triggers the formation of a fast and thin annular outflow in the form of a liquid sheet, affected by the Rayleigh–Plateau and flapping shape instability. [ABSTRACT FROM AUTHOR]

The application of elliptical injector will not only increase the atomization quality, but also reduce spray tip penetration, which has the potential to avoid wall wetting. However, so far the research on the effect of elliptical GDI nozzle on impinging spray is seldom reported. In this study, A GDI nozzle with circular and elliptical cross section shapes was employed to study the spray impingement characteristics through VOF-spray one way coupling method. The results revealed that the elliptical spray has shorter penetration as compared to circular spray, and the circular spray impingement time is earlier than the elliptical spray. Additionally, the spray rebound height of the circular spray was larger than that of the elliptical spray at the initial injection progress, while the elliptical spray rebound height became higher at the end of the injection. Furthermore, the elliptical spray impingement wall film mass and area were always smaller as compared with circular spray, and the injection pressure showed a negative influence on wall film mass. Finally, the average film thickness of the spray-wall impingement for an elliptical nozzle is observed to be reduced by 10.3% compared to that of a circular nozzle. Increasing the injection pressure is helpful to decrease the average wall film thickness. [ABSTRACT FROM AUTHOR]

Nasal sprays can deliver drugs topically to the nasal cavity and, alternatively, to the vascular system via the nasal epithelium, avoiding painful injections. The atomized spray characteristics can be optimally controlled for the desired parameters such as spray plume, cone angle, droplet velocity and droplet size distribution to target specific locations in the nasal cavity. These parameters have been investigated through computational simulations to evaluate the spray performance within the nasal cavity, however there is a lack of experimental measurements providing three-dimensional velocity data for nasal sprays. This study aims to address key elements of this gap using Phase Doppler Particle Analysis (PDPA) to measure both the droplet size and three-dimensional velocity from two over-the-counter nasal spray devices actuated with a pneumatic device delivering actuation forces equivalent to averaged pediatric, adult, and a maximum adult exertion. In addition to providing experimental data for verifying CFD simulations, this study provides multiple, and some unique, presentations of characterizing the nasal spray velocity and size behavior. Multiple new conclusions were drawn from this study, including a demonstration that the spray droplet axial velocity is the dominant velocity component, followed by radial velocity. Tangential velocity exists but is negligible by comparison. Finer droplets tended to move slower and were predominantly found in the spray core (although this may not be the case with a fluid of higher viscosity). Larger, faster droplets are found near the spray's edge in the pressure-swirl nasal sprays. The mean resultant velocity between both devices at 15 mm from the nozzle tip, actuated at the mean adult force was 16.9 m / s. The mean D 32 and D v 50 of both devices at the mean adult actuation force was 23.0 μ m and 80.0 μ m , respectively. [ABSTRACT FROM AUTHOR]

Copyright of Fire Safety Science is the property of Fire Safety Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Fire Safety Science is the property of Fire Safety Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Previous research suggested that friction-based processing is a promising method for fabricating oxide dispersion-strengthened (ODS) steel. In this study, we combined friction consolidation and friction extrusion to successfully manufacture ODS steel rods using precursor powder made with gas atomization reaction synthesis. We examined the microstructure evolution from the initial powder to the final extruded rod, which revealed the dispersion process of Y. Additionally, by comparing the microstructures of three rods extruded at different temperatures, we showed that low-temperature friction extrusion effectively enhanced microstructure uniformity and prevented grain coarsening, leading to improved mechanical properties. Our findings provide practical guidelines for adjusting processing parameters in the production of ODS steel using friction-based processing. [ABSTRACT FROM AUTHOR]

Thermochemical conversions are pathways for biomass utilization to produce various value-added energy and chemical products. For the development of novel thermochemical conversion technologies, an accurate understanding of the reaction performance and kinetics is essential. Given the diversity of the thermal analysis techniques, it is necessary to understand the features and limitations of the reactors, ensuring that the selected thermal analysis reactor meets the specific need for reaction characterization. This paper provides a critical overview of the thermal analysis reactors based on the following perspectives: 1) gas flow conditions in the reactor, 2) particle's external and internal heat and mass transfer limitations, 3) heating rate, 4) temperature distribution, 5) nascent char production and reaction, 6) liquid feeding and atomization, 7) simultaneous sampling and analyzing of bed materials, and 8) reacting atmosphere change. Finally, prospects and future research directions in the development of analysis techniques are proposed. [ABSTRACT FROM AUTHOR]

Detonation engines are gaining prominence as next-generation propulsion systems that can significantly enhance the efficiency of existing engines. This study focuses on developing an injector utilizing liquid fuel and a gas oxidizer for application in detonation engines. In order to better understand the spray characteristics suitable for the pulse detonation engine (PDE) system, an injector was fabricated by varying the Venturi nozzle exit diameter ratio and the geometric features of the fuel injection hole. Analysis of high-speed camera images revealed that the Venturi nozzle exit diameter ratio plays a crucial role in determining the characteristics of air-assist or air-blast atomization. Under the conditions of an exit diameter ratio of Re/Ri = 1.0, the formation of a liquid film at the exit was observed, and it was identified that the film's length is influenced by the geometric characteristics of the fuel injection hole. The effect of the fuel injection hole and Venturi nozzle exit diameter ratio on SMD was analyzed by using droplet diameter measurement. The derived empirical correlation indicates that the atomization mechanism varies depending on the Venturi nozzle exit diameter ratio, and it also affects the distribution of SMD. The characteristics of the proposed injector, its influence on SMD, and its velocity, provide essential groundwork and data for the design of detonation engines employing liquid fuel. [ABSTRACT FROM AUTHOR]

Copyright of Energy Chemical Industry is the property of Energy Chemical Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the present work, novel Al2O3 particles were used to reinforce heterogeneous CoCrFeMnNi high-entropy alloy (HEA) matrix composites with nano- (5.0 wt.%) and nano- + micro- (5.0 wt.% + 10.0 wt.%) specimens. Al2O3 particles were fabricated via gas atomization and spark plasma sintering. The microstructure evolution and properties, i.e., density, hardness, and room temperature compression, were systematically investigated. The results indicate that the concentration of the Cr element in the pure CoCrFeMnNi HEA and the HEA matrix composite can be effectively reduced by using a gas-atomized HEA powder as the matrix. The formation of an impurity phase can also be inhibited, while the distribution uniformity of matrix elements can be improved. The composites prepared via gas-atomized powders formed a network microstructure composed of continuous Al2O3-rich regions and isolated Al2O3-poor regions, exhibiting good plasticity and improved density. The relative densities of the pure HEA, nano- (5.0 wt.%), and nano- + micro- (5.0 wt.% + 10.0 wt.%) composites were 98.9%, 97%, and 94.1%, respectively. The results demonstrate a significant improvement in the relative densities compared to the values (97.2%, 95.7%, and 93.8%) of the composites prepared via mechanical alloying. In addition, compared to the compressive fracture strains of nano- (5.0 wt.%) and nano- + micro- (5.0 wt.% + 10.0 wt.%) composites based on the mechanically alloyed HEA powder, the values of the nano- (5.0 wt.%) and nano- + micro- (5.0 wt.% + 10.0 wt.%) specimens prepared via gas atomization and spark plasma sintering increased by 80% and 67%, respectively. [ABSTRACT FROM AUTHOR]

"Objective To explore the clinical efficacy of bronchoscopic drug injection and cryotherapy combined with atomization inhalation for tracheobronchial tuberculosis (TBTB). Methods From May 2019 to February 2023, 60 patients with TBTB treated in Nanjing Hospital Affiliated to Nanjing University of Chinese Medicine were selected as the study subjects, and were randomly divided into two groups with 30 cases in each group by the central randomization method. The control group received conventional thearpy combined with atomization of anti-tuberculosis treatment, while the observation group received bronchoscopic drug injection and cryotherapy of anti-tuberculosis on the basis of the control group. After 3 months of treatment, sputum negative conversion rate, immune function-related indicators ［CD4+, CD8+, adenosine deaminase (ADA)］, inflammation-related indicators ［γ-interferon (IFN-γ), interleukin-4 (IL-4), erythrocyte sedimentation rate (ESR)］, symptom relief time and adverse reactions were compared between two groups. Results After 3 months of treatment, IFN-γ and ESR levels, and symptom relief time in observation group were significantly lower than those in control group (P＜0.05), while the sputum negative conversion rate, CD4+, ADA and IL-4 levels were significantly higher than those in control group (P＜0.05). The incidence of total adverse reactions in observation group was lower than that in control group (10.00% vs 33.33%, χ2=4.812, P＜0.05). Conclusion Bronchoscopic drug injection and cryotherapy combined with atomization inhalation of anti-tuberculosis for TBTB has a good clinical efficacy, and it can effectively improve the immune function, relieve the inflammatory response, and reduce the adverse reactions in patients with TBTB."

In this study, the mechanisms of jet atomization were analyzed based on a frequency analysis of atomization sounds in the audible range (∼20 kHz). Jet atomization is a two-dimensional, high-speed atomization using a diaphragm, and interesting acoustic signals and atomization phenomena were detected on hydrophobic and hydrophilic diaphragms. The hydrophilic diaphragm strongly interacted and resonated with the surface wave, resulting in symmetrical jet atomization relative to the diaphragm. The resonance between the diaphragm and the surface wave was supported by a calculation of the eigenfrequency of the diaphragm and the coincidence of the droplet diameters as calculated from Lang's equation. Notably, the diaphragm excited by the ultrasonic transducer acted as a new transducer vibrating perpendicular to the transducer. As a result, when the diaphragm and the surface wave were in resonance at 2.4 MHz, a symmetrical two-dimensional high-speed jet atomization was generated in the direction perpendicular to the transducer's vibration direction. This study also revealed that the atomization state can be determined based on the acoustic analysis. This acoustic analysis of atomization sounds can be applied in more advanced atomization control, such as for providing uniform dispersions of droplets containing DNA, drugs, or microplastics. [ABSTRACT FROM AUTHOR]

Vacuum induction-melting gas atomization (VIGA) is considered a widely applied method to prepare metal powders. However, the nozzle clogging problem in the VIGA process seriously affects the continuity of production and greatly increases the economic and time costs. In the atomization initial stage, the existence of unsteady state atomization mainly results in the nozzle clogging challenge. To understand the formation mechanism of nozzle clogging, a computational fluid dynamics (CFD) model was established to simulate the influence of unsteady state atomization sequence on the primary atomization of alloy melt. Typically, there are two kinds of sequence including starting the gas before pooling the alloy (namely, GA) and pouring the alloy before opening the gas (AG). The movement trajectory of the alloy melt droplet at the end of the delivery-tube was clarified. Based on CFD simulation, the atomization sequence of AG and GA was precisely controlled in the atomization pressure range of 2.5 MPa, 3.5 MPa, and 4.5 MPa to address the nozzle clogging issue. In the GA process, relatively finer powder was obtained at 3.5 MPa without nozzle clogging occurring. In contrast, the AG process greatly reduces the probability of nozzle clogging at 2.5–4.5 MPa, the final prepared powder is coarser. The predicted results of industrial experiments and numerical simulations are consistent. This study provides theoretical support for understanding the formation mechanism of nozzle clogging during the VIGA process.

Carbon nano additives (CNAs) are critical to achieving the unique properties of functionalized composites, however, controlling the dispersion of CNAs in material matrix is always a challenging task. In this study, a simple atomization approach was successfully developed to promote the dispersion efficiency of graphene nanoplatelets (GNPs) in cement composites. This atomization approach can be integrated with the direct, indirect and combined ultrasonic stirrings in a homemade automatic stirring-atomization device. Mechanical and microstructure tests were performed on hardened cement pastes blended with GNPs in different stirring and mixing approaches. Results show that the direct ultrasonic stirrings enabled more homogeneous dispersions of GNP particles with a smaller size for a longer duration. The atomized droplets with the mean size of ∼100 ​μm largely mitigated GNPs’ agglomerations. Monolayer GNPs were observed in the cement matrix with the strength gain by up to 54%, and the total porosity decrease by 21% in 0.3 ​wt% GNPs dosage. The greatly enhanced dispersion efficiency of GNPs in cement also raised the cement hydration. This work provides an effective and manpower saving technique toward dispersing CNAs in engineering materials with great industrialization prospects.

Titanium alloys have excellent properties and are widely used in aerospace, medicine, chemical industry, and other fields. With the rapid development of the powder metallurgy and 3D printing industries, the demand for ultra-fine titanium alloy powders has increased significantly. It should be noted that the particle size of titanium alloy powders determines the application process. However, the high melting point of titanium and titanium alloys and the limitation of many factors, such as the prepared powders being easily contaminated by secondary pollution, make the preparation cost higher, which restricts their promotion and application. In this study, the research progress of micro and nano titanium alloy powder preparation process is described, and the existing problems of various processes are analyzed and discussed, and it is proposed that the direct reduction in TiO2 to obtain micro and nano titanium alloy powder is the key research direction in the future. In particular, the preparation of micro and nano titanium alloy powder by “calciothermic self-propagation process” has great industrial potential.

The direct random-phase approximation (dRPA) is used to calculate and compare atomization energies for the HEAT set and ten selected molecules of the G2-1 set using both plane waves and Gaussian-type orbitals. We describe detailed procedures to obtain highly accurate and well converged results for the projector augmented-wave method as implemented in the Vienna Ab initio Simulation Package as well as the explicitly correlated dRPA-F12 method as implemented in the TURBOMOLE package. The two approaches agree within chemical accuracy (1 kcal/mol) for the atomization energies of all considered molecules, both for the exact exchange as well as for the RPA. The root mean-square deviation is 0.41 kcal/mol for the exact exchange (evaluated using density functional theory orbitals) and 0.33 kcal/mol for exact exchange plus correlation from the RPA. [ABSTRACT FROM AUTHOR]

AbstractOptimizing the efficiency of metal powder production through brush atomization necessitates a comprehensive understanding of the interaction between the brush bristles and the molten metal, as well as its consequential effects on the fragmentation of the melt. Thus this study presents Computational Fluid Dynamics (CFD) models of the brush-melt interplay during the atomization of molten metals. The volume-of-fluid method was used to examine the various stages of melt fragmentation, from when the melt is discharged to when it settles on the brush bristles. The results revealed that the first breakup occurred close to the discharge orifice due to aerodynamic instability and fell within 13 < [Formula: see text]< 40.3. The nature of this breakup depends on the brush speed, bristle length, bristle diameter, brush density, and melt properties. A second breakup was observed when the melt contacted the rotating bristles. The melt bridges formed between two or more bristles due to attractive forces between the closely packed bristles induced by the capillary force of the melt and the surface tension of the meniscus surface are also overcome due to brush rotation. These results are in agreement with the experimental observations and are therefore sufficient for demonstrating the system.

Spray dryers have a wide range of applications in the industry for obtaining powder products. Precise control of the process is crucial, as a variety of particles can be formed through atomization, resulting in particles with different sizes, shapes, and properties. The morphology and shrinkage of the particles can be influenced by various factors such as drying rate, temperature, solution concentration, and characteristics of the drying fluid. This review covers both experimental and theoretical studies. Practical experiments involve techniques such as X-ray diffraction and camera monitoring to analyze the particles, while theoretical and mathematical models are developed to predict the drying behavior, considering factors such as drying rate and temperature. In the context of the single droplet drying (SDD) process, major phenomenological models of SDD have been discussed along with their considerations emphasizing the need for further in-depth research and more precise measurements to advance in this field. [ABSTRACT FROM AUTHOR]

A non-contact ultrasonic atomization based on the Fabry--Pérot resonator is proposed to obtain atomized droplets with a reduced droplet diameter and concentrated droplet distributions. To better understand the mechanism inside the acoustic chamber, the acoustic--fluid interactions are numerically explored inside the Fabry--Pérot resonator to achieve the precise modulation of droplets. The influence of the acoustic chamber's geometry and the ultrasonic properties on the atomized droplet diameter and distributions is investigated, aiming to establish matching relationships between the atomized droplet diameter and the geometry of the acoustic chamber. The dynamic behaviors of droplet breakup are observed with a high-speed camera to reveal the atomization mechanism of liquid droplets in high-intensity acoustic fields. The experiments demonstrate that the proposed non-contact atomization can achieve atomized water droplets with a median diameter of ~24 μm, providing an alternative to ultrasonic spray. [ABSTRACT FROM AUTHOR]

The powders produced by plasma-arc wire atomization in an argon atmosphere or air were studied for their use in 3D printing of complex-shaped metal parts and in granular metallurgy. The dependence of the morphology, structure, phase composition, and microhardness of the powders on the current and atomization conditions was established. In all studied operating modes of the plasma torch (180, 220, and 270 A), the atomized particles are predominantly spherical. The number of nonspherical particles increases with particle size. The powders atomized in an argon atmosphere exhibit a stable phase composition. The main component is iron aluminide Fe3Al (or a mixture of Fe3Al and AlFe). The α-Fe, Fe3O4, and Fe2O3 phases were also found. At currents of 220 and 270 A, the powder in –200+100 μm fraction contains the highest amount of aluminides, 83.88 and 86.30 wt.%, and the lowest content of oxides, 6.61–10.18 wt.%. In fine powders (–100+75 μm), the content of aluminides is 70.38– 28.3 wt.%), but the amount of oxides increases to 23.32–29.62 wt.%. The microhardness of oxide particles (5320–8150 MPa) is higher than that of metal particles (3070–4590 MPa). In atomization in air, the key components are Fe2O3, Fe3O4, FeO, and Al3O4. The total amount of oxides reaches 57.19–90.34%. The percentage of iron aluminides decreases significantly, and their maximum content (28.3 wt.%) is shown by the –315+200 μm powder at a plasma torch current of 270 A. In the finest powder fraction of –100+75 μm, the content of aluminides ranges from 6.2 to 15.36 wt.%. The average microhardness of metal particles is much lower (2750–4940 MPa) than that of oxide particles (4500–7460 MPa). It was found that the best material in terms of phase composition, structure, hardness, and shape factor was produced by atomization of a flux-cored wire in an argon atmosphere. In atomization in air, intense oxidation processes occur. [ABSTRACT FROM AUTHOR]

Rotary atomization is used in a wide variety of fields, exploiting the external control option of the spray while no high-pressure fluid is needed. Most papers on rotary atomization deal with liquid jet breakup, while external spray characteristics are rarely evaluated; this is performed currently. The water spray was measured by a two-component phase Doppler anemometer. The optical setup requires a special measurement chamber to avoid spray deposition on the optical components. Therefore, the first goal was to find a proper filter that enables the removal of biased droplets by secondary flows. Since most droplets have a similar radial-to-tangential velocity ratio at each measurement point, i.e., scattering around a line, this was the first component of the best filter. The second component was the need for a positive radial velocity component. This filter efficiently removed droplets originating from alternative processes, increasing the R2 of the line fit. The physical soundness of this filter was checked by evaluating the effect of filtering on the angle of the velocity components of each droplet at a given measurement point. The proposed filter efficiently detected recirculation, a secondary effect of the measurement setup with less regular dataset shapes. Finally, the slope and intercept values of the fitted lines were evaluated and presented. The mean of the former followed the same trend irrespective of the rotational speed and the mass flow rate; it was principally dependent on the radial distance from the atomizer. The intercept showed a regular but less universal behavior. [ABSTRACT FROM AUTHOR]

During the discharge of floodwater from a hydropower station, a significant number of water droplets in motion are created in the downstream space. These droplets vary in size and velocity, causing challenges in determining the particle size and velocity distribution of the flood discharge atomized droplets. Currently, the particle-size distribution and velocity distribution of atomized droplets are considered to be independent, and the gamma function is used to describe the particle-size distribution and velocity distribution of droplets separately. However, a joint distribution of atomized droplet size and velocity is lacking. This paper uses the basic theory of maximum entropy to study the combined distribution of droplet size and velocity in the atomized flow caused by jet overflow. The present model was in a good agreement with experimental data, providing a method for the theoretical study of droplet size and velocity distribution in flood discharge atomization. [ABSTRACT FROM AUTHOR]

Flash boiling atomization (FBA) is a promising approach for enhancing spray atomization, which can generate a fine and more evenly distributed spray by increasing the fuel injection temperature or reducing the ambient pressure. However, when the outlet speed of the nozzle exceeds 400 m/s, investigating high-speed flash boiling atomization (HFBA) becomes quite challenging. This difficulty arises from the involvement of many complex physical processes and the requirement for a very fine mesh in numerical simulations. In this study, an HFBA model for gasoline direct injection (GDI) is established. This model incorporates primary and secondary atomization, as well as vaporization and boiling models, to describe the development process of the flash boiling spray. Compared to low-speed FBA, these physical processes significantly impact HFBA. In this model, the Eulerian description is utilized for modeling the gas, and the Lagrangian description is applied to model the droplets, which effectively captures the movement of the droplets and avoids excessive mesh in the Eulerian coordinates. Under various conditions, numerical solutions of the Sauter mean diameter (SMD) for GDI show good agreement with experimental data, validating the proposed model's performance. Simulations based on this HFBA model investigate the influences of fuel injection temperature and ambient pressure on the atomization process. Numerical analyses of the velocity field, temperature field, vapor mass fraction distribution, particle size distribution, and spray penetration length under different superheat degrees reveal that high injection temperature or low ambient pressure significantly affects the formation of small and dispersed droplet distribution. This effect is conducive to the refinement of spray particles and enhances atomization. [ABSTRACT FROM AUTHOR]

Aluminum/tetrahydrodicyclopentadiene/oleic acid (Al/JP-10/OA) nanofluid fuel is considered a potential fuel for aircraft powered by aviation turbine engines. However, an optimized formula for an Al/JP-10/OA system inducing a secondary atomization and micro-explosion effect and improving the burning performance needs to be developed. With this aim, in this work, the combustion characteristics of pure JP-10, JP-10/OA, JP-10/Al, and Al/JP-10/OA were experimentally tested, and a comparative analysis was conducted. Specifically, the influence of the surfactant and nanoparticle concentrations on the combustion characteristics of Al/JP-10/OA nanofluid fuel, including the flame structure, the flame temperature, the burning rate, the secondary atomization and micro-explosion effect, etc., were evaluated in detail. The results demonstrate that the addition of OA surfactant and Al nanoparticles had a significant effect on the burning rate of fuel droplets. The OA had an inhibition effect, while the Al nanoparticles had a promotion effect. As both OA and Al nanoparticles were added to the JP-10, the synergetic effect had to be considered. At the optimum ratio of OA to Al for the best suspension stability, there is a critical Al concentration of 1.0 wt.% from promotion to inhibition with increases in the Al concentration. The addition of OA and Al nanoparticles induced the secondary atomization and micro-explosion, resulting in an unsteady combustion and chaotic flame structure. The transient flame temperature of hundreds of Kelvins increased, the high-temperature flame zone widened, and thus, the energy release was elevated. Therefore, the combustion performance and energy release of Al/JP-10/OA nanofluid fuel can be improved through the secondary atomization and micro-explosion effect induced by the surfactant and nanoparticles. [ABSTRACT FROM AUTHOR]