Powder Technology最新文献_第3页

Nanoadditives to mitigate jamming in cohesive granular media

IF 4.5 2区工程技术

Powder Technology Pub Date : 2025-02-20 DOI: 10.1016/j.powtec.2025.120756

F.J. Durán-Olivencia , M.A. Martín-Alfonso , F. Pontiga , C. Soria-Hoyo , H. Moreno , J.M. Valverde

{"title":"Nanoadditives to mitigate jamming in cohesive granular media","authors":"F.J. Durán-Olivencia , M.A. Martín-Alfonso , F. Pontiga , C. Soria-Hoyo , H. Moreno , J.M. Valverde","doi":"10.1016/j.powtec.2025.120756","DOIUrl":"10.1016/j.powtec.2025.120756","url":null,"abstract":"<div><div>Handling and conveying cohesive granular media are common challenges for many industries, which demand smooth and uninterrupted granular flows. Cohesion settles at the cores of these problems, especially at high temperatures, when it rises sharply and flow patterns become intermittent; then, jamming, halts, and shutdowns.</div><div>Here, we explore shielding limestone particles with nanoadditives to mitigate the adverse effect of cohesion, especially at high temperatures. The work focuses on concentrated solar plants assisted by the calcium looping cycle, a high-temperature environment plagued with jamming vulnerabilities. Experiments analyze the evolution of tensile strength as samples expand and fluidize freely, using three nanomaterials to coat fine limestone powders: silica, titania, and alumina. To investigate the efficacy of these coatings, samples were preconsolidated (up to 2kPa) before fluidizing at high temperatures (up to 500°C)—conditions that soften the contacts and cause cohesion to escalate. The results showed how discrete layers of nanoadditives shape stiffer surfaces, preventing particles from softening at high temperatures, and thereby limiting the contact area dilation that fuels cohesion.</div><div>Coatings were prepared considering the optimal amount of nanoadditives to introduce minimal inert material. Concentrations below 1wt% were enough to ensure uniform coatings and promote easy-flow regimes. Yet at 500°C, only alumina coatings achieved easy-flow dynamics, offering a sintering shielding effect that reduces the rise in tensile strength up to 62%. This is an outstanding conclusion to mitigate jamming in fine powders, which is paramount for a broad spectrum of granular processes that require transporting and storing cohesive granular media at high temperatures.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"456 ","pages":"Article 120756"},"PeriodicalIF":4.5,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143508056","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Comparative evaluation of Peschl and FT4 full-bed rotational shear cells for powder flow characterization

IF 4.5 2区工程技术

Powder Technology Pub Date : 2025-02-18 DOI: 10.1016/j.powtec.2025.120810

Sara Koynov , Kristen Duda , Plinio A. De los Santos , David J. Goldfarb

{"title":"Comparative evaluation of Peschl and FT4 full-bed rotational shear cells for powder flow characterization","authors":"Sara Koynov , Kristen Duda , Plinio A. De los Santos , David J. Goldfarb","doi":"10.1016/j.powtec.2025.120810","DOIUrl":"10.1016/j.powtec.2025.120810","url":null,"abstract":"<div><div>The method of shear cell testing plays a pivotal role in assessing the flowability of powders, notably in the context of evaluating pharmaceutical formulations and processes. Despite numerous studies on shear cell methodology and its diverse applications, there remains a need to compare the performance of specific shear cell designs. This study addresses this gap by offering a comprehensive comparison of two full-bed rotational shear cells – the Peschl and FT4 cells. The evaluation focuses on assessing the precision and accuracy of each instrument, considering six materials: two reference materials with well-established behavior and four pharmaceutically relevant materials. Key parameters obtained from the measured yield loci were analyzed and compared, shedding light on the differences in performance between the two shear cells. Statistical analysis using regression methods revealed the significance of not only the test material but also the shear cell used for measurement, emphasizing the influential role of shear cell design. Additionally, this work delves into the significance of powder bed density during shear cell measurements and its broader implications for comprehensive powder characterization, providing valuable insights for the field of material science and pharmaceutical formulation.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"456 ","pages":"Article 120810"},"PeriodicalIF":4.5,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143464409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Exploration of corn starch dust combustion and explosion mechanisms via thermal decomposition and functional group changes

IF 4.5 2区工程技术

Powder Technology Pub Date : 2025-02-18 DOI: 10.1016/j.powtec.2025.120816

Bing Wang , Chuanbiao Zhang , Xin Zhang , Yue Zhao , Suyue Li , Runqing Liu , Shaoqian Cheng , Yanhua Lan , Yang Zhang , Weiguo Cao

{"title":"Exploration of corn starch dust combustion and explosion mechanisms via thermal decomposition and functional group changes","authors":"Bing Wang , Chuanbiao Zhang , Xin Zhang , Yue Zhao , Suyue Li , Runqing Liu , Shaoqian Cheng , Yanhua Lan , Yang Zhang , Weiguo Cao","doi":"10.1016/j.powtec.2025.120816","DOIUrl":"10.1016/j.powtec.2025.120816","url":null,"abstract":"<div><div>In specific conditions, corn starch, due to its explosive characteristics as a fine powder, can act as a catalyst for a dust explosion. In this paper, test techniques were utilized to examine the thermal decomposition and ignition process of corn starch, as well as to probe into its fundamental combustion mechanism. Upon increasing the concentration of corn starch, there was an initial tendency for both the flame propagation velocity and length to rise, followed by a subsequent decrease. The results revealed that a large amount of volatile gases was precipitated from corn starch during pyrolysis, and these gases reacted with oxygen during combustion. The reaction rate was related to the concentration of corn starch, causing the flame propagation velocity and length to initially show an increasing trend and then decrease as the concentration of corn starch increased. Combined with the In-situ DRIFTS test, the study investigated the change process of surface functional groups during the combustion of corn starch. The combustion process of corn starch conforms to the mechanism of surface heterogeneous ignition. When combustion occurred rapidly, the temperature during volatile matter combustion reflectd that of corn starch particle combustion, making corn starch more prone to surface ignition.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"456 ","pages":"Article 120816"},"PeriodicalIF":4.5,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143464408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Study on the non-destructive evaluation of overall particle dispersion within nanocomposites by nonlinear ultrasonic and its applicability

IF 4.5 2区工程技术

Powder Technology Pub Date : 2025-02-17 DOI: 10.1016/j.powtec.2025.120815

Shuo Zhang , Hanqing Wang , Li Cheng , Wei Fang , Yonglin Qiu , Lijun Yang , Ruijin Liao

{"title":"Study on the non-destructive evaluation of overall particle dispersion within nanocomposites by nonlinear ultrasonic and its applicability","authors":"Shuo Zhang , Hanqing Wang , Li Cheng , Wei Fang , Yonglin Qiu , Lijun Yang , Ruijin Liao","doi":"10.1016/j.powtec.2025.120815","DOIUrl":"10.1016/j.powtec.2025.120815","url":null,"abstract":"<div><div>The dispersion of nanoparticles in nanocomposites seriously affects the material properties. However, the current nanoparticle dispersibility assessment mainly relies on the microscopic imaging method, which has the limitations of being lossy and having a narrow detection area, and is unable to realize the assessment of the overall dispersibility of the particles in bulk materials. This article uses nonlinear ultrasonic technology (NLUS) to achieve the overall dispersion evaluation of nanoparticles. Theoretical and experimental results show that: the nanoparticles nonlinear coefficient (Δ<em>β</em>) and the particle agglomeration degree (<em>K</em>) approximately satisfy the linear variation relationship (R<sup>2</sup> > 0.9), while the smaller the elastic modulus of the particles is, the larger the slope of the Δ<em>β</em>-K fitting function is; the results of the NLUS test are not affected by the factors of surface modification. The error between the NLUS nondestructive evaluation results of particle dispersion and the SEM lossy test results ranged from 3 % to 15 %. The single detection region of NLUS is a three-dimensional region of ultrasonic wave propagation and the single detection time is short, these features enable NLUS to be applied in the rapid non-destructive evaluation of the overall dispersion of large volume polymer-based nano-dielectric material particles.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"456 ","pages":"Article 120815"},"PeriodicalIF":4.5,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143474416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Spray freeze-drying for inhalable L-leucine, mannitol-based microparticles: The impact of process variables, L-leucine, and crystallinity on Aerosolization properties

IF 4.5 2区工程技术

Powder Technology Pub Date : 2025-02-16 DOI: 10.1016/j.powtec.2025.120788

Lorena Pasero , Adamo Sulpizi , Tomaso Guidi , Roberto Pisano

{"title":"Spray freeze-drying for inhalable L-leucine, mannitol-based microparticles: The impact of process variables, L-leucine, and crystallinity on Aerosolization properties","authors":"Lorena Pasero , Adamo Sulpizi , Tomaso Guidi , Roberto Pisano","doi":"10.1016/j.powtec.2025.120788","DOIUrl":"10.1016/j.powtec.2025.120788","url":null,"abstract":"<div><div>In this study, microparticles carrying salbutamol sulphate were produced by pneumatic spray freeze-drying. The optimal particle size was assessed through a model, associated with a design of experiments. Growing solid concentrations and <span><math><msub><mi>N</mi><mn>2</mn></msub></math></span> flow rate led to decreasing geometric diameters, while an opposite effect was associated with the feed flow rate. The aerodynamic diameter, instead, increased at increasing solid concentrations. Moreover, the role of crystallinity in determining the microparticles' flowability was evaluated upon the incorporation of L-leucine. The addition of the amino acid induced the formation of two morphologies with different degrees of crystallinity. The absence of recrystallization significantly improved the aerosolization properties of the microparticles up to a maximum fine particle fraction (48 %) and a minimum mass median aerodynamic diameter (2 μm) at 10 % (<em>w/w</em> db) L-leucine. This result disclosed the influence of polymorphism on the microparticles' cohesiveness, proving the dependency of the microparticles' aerodynamics on L-leucine and mannitol crystallinity.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"455 ","pages":"Article 120788"},"PeriodicalIF":4.5,"publicationDate":"2025-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143454552","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Efficient and synergistic preparation of HNS-based energetic composite microspheres by the continuous drop-ball method and optimization of their multi-dimensional performance

IF 4.5 2区工程技术

Powder Technology Pub Date : 2025-02-16 DOI: 10.1016/j.powtec.2025.120814

Songchao Shi , Chenhe Feng , Wenqing Li , Lei Gao , Haoxing Cao , Baoyun Ye , Jingyu Wang , Chuanhao Xu , Chongwei An

{"title":"Efficient and synergistic preparation of HNS-based energetic composite microspheres by the continuous drop-ball method and optimization of their multi-dimensional performance","authors":"Songchao Shi , Chenhe Feng , Wenqing Li , Lei Gao , Haoxing Cao , Baoyun Ye , Jingyu Wang , Chuanhao Xu , Chongwei An","doi":"10.1016/j.powtec.2025.120814","DOIUrl":"10.1016/j.powtec.2025.120814","url":null,"abstract":"<div><div>This study presents an innovative continuous ball-dropping device combined with high-speed stirring and curing to successfully produce HNS-based energetic composite microspheres with uniform components and complete coatings. The effects of process parameters such as binder content, suspension concentration, continuous phase concentration, and stirring rate on the morphology and particle size distribution of the microspheres were systematically examined. The study further investigates the impact of the continuous ball-dropping method on fluidity, chemical structure, bulk density, thermal properties, mechanical sensitivity, and combustion properties of the microspheres. Results show that compared to Nano-HNS, the HNS-based microspheres prepared by the ball-dropping method exhibit improved fluidity (angle of repose: 37.97° vs 22.09°), higher bulk density (0.453 g·cm<sup>−3</sup> vs 0.552 g·cm<sup>−3</sup>), and increased activation energy. Mechanical sensitivity tests show a significant safety improvement, with critical impact energy increasing from 2.5 J to 40 J and friction sensitivity rising from 108 N to 180 N. The combustion performance of microspheres prepared by this method exhibits a larger flame area and shorter combustion time, thereby improving energy release efficiency. Compression performance improves as well, with microspheres exhibiting increased compression resistance, rising from 14.04 MPa to 37.02 MPa compared to traditional methods. In conclusion, the continuous drop ball method, combined with high-speed stirring and curing, efficiently produces fully coated energetic composite microspheres, offering a promising route for the large-scale industrial production of energetic materials.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"455 ","pages":"Article 120814"},"PeriodicalIF":4.5,"publicationDate":"2025-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143454487","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Analysis of the screw feeding process in powder-based additive friction stir deposition

IF 4.5 2区工程技术

Powder Technology Pub Date : 2025-02-15 DOI: 10.1016/j.powtec.2025.120791

Wenguang Nan , Wenbin Xuan , Ziming He , Haimeng Hou , Zhonggang Sun , Wenya Li

{"title":"Analysis of the screw feeding process in powder-based additive friction stir deposition","authors":"Wenguang Nan , Wenbin Xuan , Ziming He , Haimeng Hou , Zhonggang Sun , Wenya Li","doi":"10.1016/j.powtec.2025.120791","DOIUrl":"10.1016/j.powtec.2025.120791","url":null,"abstract":"<div><div>The screw-feeding process in powder-based additive friction stir deposition (AFSD) is analysed in this work, in which the effect of feeding conditions on the choking/jamming problem and the feeding rate is explored through experiment and numerical simulation using Discrete Element Method (DEM). The results show that a narrow gap between the funnel outlet and the base is prone to particle jamming, which would entirely block the funnel outlet and produce a huge force on the screw. Jamming is more easily to occur when the rotational speed is relatively larger than the translational speed, and a mathematical model of the critical rotational speed above which the particle jamming and blockage would occur is proposed. Jamming is also sensitive to the design of the funnel outlet, in which a contracting outlet would make the choking and jamming problem more serious. For the feeding conditions without jamming, the feeding rate not only depends on the rotational speed of the screw but also is significantly affected by the translational speed. The feeding rate is linear to the rotational speed only when it is larger than a critical value, and this critical rotational speed increases with translational speed. The results also clarify that a good understanding of the screw-feeding process is essential for powder-based AFSD, in which an example of successful manufacturing of a 3D part is briefly illustrated in this work.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"455 ","pages":"Article 120791"},"PeriodicalIF":4.5,"publicationDate":"2025-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143446124","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Surrogate model of DEM simulation for binary-sized particle mixing and segregation

IF 4.5 2区工程技术

Powder Technology Pub Date : 2025-02-15 DOI: 10.1016/j.powtec.2025.120811

Naoki Kishida, Hideya Nakamura, Shuji Ohsaki, Satoru Watano

{"title":"Surrogate model of DEM simulation for binary-sized particle mixing and segregation","authors":"Naoki Kishida, Hideya Nakamura, Shuji Ohsaki, Satoru Watano","doi":"10.1016/j.powtec.2025.120811","DOIUrl":"10.1016/j.powtec.2025.120811","url":null,"abstract":"<div><div>Segregation is a well-known phenomenon that occurs during powder mixing, wherein particles with similar properties are collected from specific regions of a bulk powder. Numerical simulation using the discrete element method (DEM) is recognized as a potent tool for investigating and predicting segregation. However, DEM simulations are computationally expensive. To address the high computational overhead, in our prior work, we proposed a machine-learning-based surrogate model for DEM simulation, namely, recurrent neural network with stochastically calculated random motion (RNNSR). The model was designed to predict the local mean component of the particle behavior using the Lagrangian approach and the local variability component of the particle behavior using the Eulerian approach. However, the RNNSR was demonstrated exclusively for monodisperse particles with homogeneous properties. Hence, in the current study, we extended the RNNSR to simulate the mixing and segregation of powders with inhomogeneous properties. The dependence of the particle size on the Lagrangian and Eulerian behaviors of the particles was investigated. Based on this analysis, an extended-RNNSR was developed for binary-sized particle system by adding the particle size data for the training data. The prediction accuracy of the extended-RNNSR was evaluated in terms of the mixing degree, particle velocity, granular temperature, and computing speed. It was demonstrated that the extended-RNNSR constructed on learning data initiated from the randomly mixed initial condition could predict mixing and segregation initiated from both segregated as well as the randomly mixed initial conditions. The extended-RNNSR also demonstrated a much faster computing speed than the DEM.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"455 ","pages":"Article 120811"},"PeriodicalIF":4.5,"publicationDate":"2025-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143438041","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of oxygen concentration on the minimum explosible concentration of aluminum powders

IF 4.5 2区工程技术

Powder Technology Pub Date : 2025-02-15 DOI: 10.1016/j.powtec.2025.120794

Wookyung Kim , Yasuko Ueno , Rinrin Saeki , Tomoyuki Johzaki , Takuma Endo , Minhyeok Lee , Kwangseok Choi , Kazunori Kuwana

{"title":"Effect of oxygen concentration on the minimum explosible concentration of aluminum powders","authors":"Wookyung Kim , Yasuko Ueno , Rinrin Saeki , Tomoyuki Johzaki , Takuma Endo , Minhyeok Lee , Kwangseok Choi , Kazunori Kuwana","doi":"10.1016/j.powtec.2025.120794","DOIUrl":"10.1016/j.powtec.2025.120794","url":null,"abstract":"<div><div>This study focuses on the explosion characteristics of aluminum (Al) powders, which have garnered significant attention as energy carriers due to their high energy density and reactivity. Specifically, it investigates the effect of oxygen concentration on the minimum explosible concentration (MEC). The experimental apparatus outlined in JIS Z8818 was modified to conduct experiments using O2-N2 mixtures. Various O2 concentrations ranging from 10 vol% to 50 vol% were tested to measure the MEC of Al powders. The results indicate that the MEC decreases with increasing O2 concentration, highlighting the critical role of O2 in the explosiveness of Al powders. Additionally, the validity of the theoretical model was verified by comparing the results of the continuum model calculations with the experimental data. This research provides a more accurate assessment of the explosion hazards of Al powders and offers foundational data for creating safer working environments. Furthermore, as a fundamental study, it contributes to the development of combustion systems for propulsion and energy applications, enhancing the understanding and design of efficient and safe energy systems.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"455 ","pages":"Article 120794"},"PeriodicalIF":4.5,"publicationDate":"2025-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143446125","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Meso-scale numerical analysis of the role of Van der Waals adhesion and static friction in fluidized beds of fine solids

IF 4.5 2区工程技术

Powder Technology Pub Date : 2025-02-15 DOI: 10.1016/j.powtec.2025.120763

Youssef Badran , Dorian Dupuy , Bruno Blais , Vincent Moureau , Renaud Ansart , Jamal Chaouki , Olivier Simonin

引用次数: 0