Pub Date : 2025-10-24DOI: 10.1016/j.apt.2025.105088
Lihua Cao , Shuang Liu , Keyu Wang , Dali Ding , Cheng Li
Solid particles cause severe erosion damage to steam turbine flow components in high-parameter and large-capacity units, which affects the economy and reliability. In this paper, the explicit dynamics method was used to simulate the process of solid particle erosion (SPE) on the regulating stage blade of ultra-supercritical steam turbine. A random multi-particle erosion model was established to investigate the effects of particle shape, size, and impact angle on erosion characteristics, and further analyze the erosion damage mechanisms. The results show that when the particle size increases, the erosion rate and blade surface roughness increase, and the blade surface roughness caused by flaky particle erosion is greater than that caused by the equal volume of spherical particles. For different particle shapes, as the impact angle increases, the volume erosion rate initially increases and then decreases, reaching its peak value at an impact angle of about 30°. The erosion damage mechanisms caused by different shape particles are different, the spherical particles mainly cause micro-ploughing and extrusion-forging, while the flaky particles cause micro-cutting and extrusion-forging.
{"title":"Research on erosion characteristics and mechanisms of regulating stage blade under multi-particle impact","authors":"Lihua Cao , Shuang Liu , Keyu Wang , Dali Ding , Cheng Li","doi":"10.1016/j.apt.2025.105088","DOIUrl":"10.1016/j.apt.2025.105088","url":null,"abstract":"<div><div>Solid particles cause severe erosion damage to steam turbine flow components in high-parameter and large-capacity units, which affects the economy and reliability. In this paper, the explicit dynamics method was used to simulate the process of solid particle erosion (SPE) on the regulating stage blade of ultra-supercritical steam turbine. A random multi-particle erosion model was established to investigate the effects of particle shape, size, and impact angle on erosion characteristics, and further analyze the erosion damage mechanisms. The results show that when the particle size increases, the erosion rate and blade surface roughness increase, and the blade surface roughness caused by flaky particle erosion is greater than that caused by the equal volume of spherical particles. For different particle shapes, as the impact angle increases, the volume erosion rate initially increases and then decreases, reaching its peak value at an impact angle of about 30°. The erosion damage mechanisms caused by different shape particles are different, the spherical particles mainly cause micro-ploughing and extrusion-forging, while the flaky particles cause micro-cutting and extrusion-forging.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 11","pages":"Article 105088"},"PeriodicalIF":4.2,"publicationDate":"2025-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145358347","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}
Pub Date : 2025-10-24DOI: 10.1016/j.apt.2025.105081
Seungwook Lee, Donggeun Lee
As semiconductor devices scale down to sub-5 nm nodes, the removal of nanoscale contaminants without damaging patterns has become increasingly critical. While physical cleaning methods such as liquid jet spray offer advantages over chemical cleaning, balancing high particle removal efficiency (PRE) with structural integrity remains challenging. In this study, a predictive model was developed for structural damage in silicon line/space patterns subjected to high-speed droplet impact. The model evaluates the principal stress induced in line sidewalls based on pattern geometry and impact conditions, introducing the concept of a damage radius to estimate the extent of damage. Experimental validation was conducted using Ti nanoparticles (10–60 nm) deposited on Si patterns with various geometries and cleaned at droplet velocities of 33–84 m/s. The predicted damage radius showed reasonable agreement with the experimental observations. Among the geometric parameters of line structures, aspect ratio was found to be the dominant factor influencing structural damage, whereas line spacing had minimal effect. In contrast, line spacing significantly affected cleaning performance. Finally, a universal parameter governing damage rate was identified, clarifying its functional dependence on impact and structural parameters.
{"title":"Modeling structural damage to line/space patterns from high-speed droplet impact in particulate cleaning on patterned wafers","authors":"Seungwook Lee, Donggeun Lee","doi":"10.1016/j.apt.2025.105081","DOIUrl":"10.1016/j.apt.2025.105081","url":null,"abstract":"<div><div>As semiconductor devices scale down to sub-5 nm nodes, the removal of nanoscale contaminants without damaging patterns has become increasingly critical. While physical cleaning methods such as liquid jet spray offer advantages over chemical cleaning, balancing high particle removal efficiency (PRE) with structural integrity remains challenging. In this study, a predictive model was developed for structural damage in silicon line/space patterns subjected to high-speed droplet impact. The model evaluates the principal stress induced in line sidewalls based on pattern geometry and impact conditions, introducing the concept of a damage radius to estimate the extent of damage. Experimental validation was conducted using Ti nanoparticles (10–60 nm) deposited on Si patterns with various geometries and cleaned at droplet velocities of 33–84 m/s. The predicted damage radius showed reasonable agreement with the experimental observations. Among the geometric parameters of line structures, aspect ratio was found to be the dominant factor influencing structural damage, whereas line spacing had minimal effect. In contrast, line spacing significantly affected cleaning performance. Finally, a universal parameter governing damage rate was identified, clarifying its functional dependence on impact and structural parameters.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 11","pages":"Article 105081"},"PeriodicalIF":4.2,"publicationDate":"2025-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145358351","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}
Personalized medicine, which involves manufacturing and providing medications tailored to individual patients, has gained increasing attention in recent years. To support this approach, the authors have developed a compact, modular tablet manufacturing system, which integrates powder dispensing, mixing, compression, and tablet ejection in a single unit. In this study, we evaluated the impact of the powder properties of the pharmaceutical raw materials on the product and process performance of the integrated single-dose manufacturing system. A model study was conducted using vitamin B2 tablets, with raw vitamin B2 powder either used as-is or subjected to granulation to modify its properties. By changing the type of granules and powders used in this manufacturing system, tablets with different physical properties were obtained. A comprehensive evaluation of the correlation between powder properties and yield revealed that the particle size distribution and angle of repose were key factors influencing the process yield. We anticipate that these results will show that it is possible to predict the quality of tablets from the physical properties of the raw materials and facilitate the manufacture of high-quality, high-yield, personalized tablets.
{"title":"Impact of powder properties on the product and process performance of an integrated single-dose manufacturing system","authors":"Kazuya Tanabe , Takuya Nagato , Yusuke Hayashi , Hirokazu Sugiyama , Kohei Tahara","doi":"10.1016/j.apt.2025.105078","DOIUrl":"10.1016/j.apt.2025.105078","url":null,"abstract":"<div><div>Personalized medicine, which involves manufacturing and providing medications tailored to individual patients, has gained increasing attention in recent years. To support this approach, the authors have developed a compact, modular tablet manufacturing system, which integrates powder dispensing, mixing, compression, and tablet ejection in a single unit. In this study, we evaluated the impact of the powder properties of the pharmaceutical raw materials on the product and process performance of the integrated single-dose manufacturing system. A model study was conducted using vitamin B<sub>2</sub> tablets, with raw vitamin B<sub>2</sub> powder either used as-is or subjected to granulation to modify its properties. By changing the type of granules and powders used in this manufacturing system, tablets with different physical properties were obtained. A comprehensive evaluation of the correlation between powder properties and yield revealed that the particle size distribution and angle of repose were key factors influencing the process yield. We anticipate that these results will show that it is possible to predict the quality of tablets from the physical properties of the raw materials and facilitate the manufacture of high-quality, high-yield, personalized tablets.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 11","pages":"Article 105078"},"PeriodicalIF":4.2,"publicationDate":"2025-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145358350","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}
Pub Date : 2025-10-23DOI: 10.1016/j.apt.2025.105085
M. Bozoglu , D. Misiulia , Y. Sinnwell , T. Zhu , M. Smaga , T. Beck , S. Antonyuk
Metastable austenitic stainless steels are well known for their ability to undergo deformation-induced -martensite formation (DIM), which enhances strength and wear resistance. This study examines DIM in AISI 347 stainless steel under high-velocity particle impacts. Micro-shot peening was performed using a self-developed cold spray setup, where nozzle inlet temperature and line distance were varied to control particle velocity and impact frequency. Surface properties of the peened samples were characterized by confocal microscopy and X-ray diffraction. Particle velocities were determined by high-speed velocimetry and validated against CFD simulations, which incorporated particle shape data from micro-computed tomography. The close agreement between experimental and numerical results confirms the reliability of the modeling approach. Both methods consistently revealed that particle velocity increases with higher nozzle inlet temperatures. However, elevated temperatures led to a reduction in martensite content due to surface heating effects. The highest martensite fractions were observed at lower temperatures (25 and 100 °C), coinciding with increased compressive residual stresses at reduced line distances. At 300 °C, stress relaxation became predominant, resulting in decreased residual stress levels. These findings demonstrate that DIM can be effectively controlled through targeted adjustment of micro-shot peening parameters. This study provides novel insights into martensitic transformation behavior under high-velocity impacts and establishes a foundation for optimizing micro-shot peening modification processes.
{"title":"Investigation of the deformation-induced α′-martensite formation of metastable austenitic stainless steel AISI 347 by high-velocity particle collisions","authors":"M. Bozoglu , D. Misiulia , Y. Sinnwell , T. Zhu , M. Smaga , T. Beck , S. Antonyuk","doi":"10.1016/j.apt.2025.105085","DOIUrl":"10.1016/j.apt.2025.105085","url":null,"abstract":"<div><div>Metastable austenitic stainless steels are well known for their ability to undergo deformation-induced <span><math><mrow><mi>α</mi><mo>′</mo></mrow></math></span>-martensite formation (DIM), which enhances strength and wear resistance. This study examines DIM in AISI 347 stainless steel under high-velocity particle impacts. Micro-shot peening was performed using a self-developed cold spray setup, where nozzle inlet temperature and line distance were varied to control particle velocity and impact frequency. Surface properties of the peened samples were characterized by confocal microscopy and X-ray diffraction. Particle velocities were determined by high-speed velocimetry and validated against CFD simulations, which incorporated particle shape data from micro-computed tomography. The close agreement between experimental and numerical results confirms the reliability of the modeling approach. Both methods consistently revealed that particle velocity increases with higher nozzle inlet temperatures. However, elevated temperatures led to a reduction in martensite content due to surface heating effects. The highest martensite fractions were observed at lower temperatures (25 and 100 °C), coinciding with increased compressive residual stresses at reduced line distances. At 300 °C, stress relaxation became predominant, resulting in decreased residual stress levels. These findings demonstrate that DIM can be effectively controlled through targeted adjustment of micro-shot peening parameters. This study provides novel insights into martensitic transformation behavior under high-velocity impacts and establishes a foundation for optimizing micro-shot peening modification processes.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 11","pages":"Article 105085"},"PeriodicalIF":4.2,"publicationDate":"2025-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145358233","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}
Pub Date : 2025-10-16DOI: 10.1016/j.apt.2025.105082
Fatih Uzun, Alexander M. Korsunsky
This study introduces OxDEM, a novel strain-energy-based formulation of the Discrete Element Method, in which both normal and tangential contact forces are derived exclusively from strain energy. Unlike the widely used Hertz-Mindlin approach that relies on empirically calibrated stiffness and friction parameters, OxDEM eliminates the need for such inputs. Tangential interactions emerge naturally from relative velocities and shear strains, introducing an intrinsic dissipation mechanism without requiring empirical parameters. A series of benchmark simulations, ranging from single-particle impacts to multi-particle settling, demonstrate that OxDEM reproduces physically consistent dynamics, including energy transfer, emergent dissipation through tangential interactions, and collective particle rearrangements, while avoiding artefacts linked to parameter calibration. The present formulation deliberately omits explicit damping forces to isolate the core mechanics, leaving their incorporation for future development. By unifying normal and tangential responses under a common strain energy framework, OxDEM establishes a physically grounded and parameter-efficient pathway for predictive modelling of granular systems, with clear potential for extension to fluid-particle systems and non-spherical discrete element interactions.
{"title":"OxDEM: Discrete element method based on strain energy formulation","authors":"Fatih Uzun, Alexander M. Korsunsky","doi":"10.1016/j.apt.2025.105082","DOIUrl":"10.1016/j.apt.2025.105082","url":null,"abstract":"<div><div>This study introduces OxDEM, a novel strain-energy-based formulation of the Discrete Element Method, in which both normal and tangential contact forces are derived exclusively from strain energy. Unlike the widely used Hertz-Mindlin approach that relies on empirically calibrated stiffness and friction parameters, OxDEM eliminates the need for such inputs. Tangential interactions emerge naturally from relative velocities and shear strains, introducing an intrinsic dissipation mechanism without requiring empirical parameters. A series of benchmark simulations, ranging from single-particle impacts to multi-particle settling, demonstrate that OxDEM reproduces physically consistent dynamics, including energy transfer, emergent dissipation through tangential interactions, and collective particle rearrangements, while avoiding artefacts linked to parameter calibration. The present formulation deliberately omits explicit damping forces to isolate the core mechanics, leaving their incorporation for future development. By unifying normal and tangential responses under a common strain energy framework, OxDEM establishes a physically grounded and parameter-efficient pathway for predictive modelling of granular systems, with clear potential for extension to fluid-particle systems and non-spherical discrete element interactions.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 11","pages":"Article 105082"},"PeriodicalIF":4.2,"publicationDate":"2025-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145332262","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}
Pub Date : 2025-10-10DOI: 10.1016/j.apt.2025.105075
Toshiki Yamaoka , Hideo Takashima , Kohei Tahara
We developed a statistical control approach combining process variables and near-infrared (NIR) spectroscopy to detect deviations in the continuous manufacturing of oral solid dosage forms. Multivariate statistical process control (MSPC) models were independently developed for process variables during wet granulation and drying, as well as for NIR spectral data. Data obtained from a laboratory-scale continuous manufacturing unit (ConsiGma™-1) were used to construct principal component analysis based MSPC models, enabling identification of abnormal batches via calculated Hotelling’s T2 and Q statistics. The combined use of NIR and process variable monitoring for the MSPC technique enabled the accurate detection of process deviations and product quality defects, demonstrating its effectiveness. In batches with altered formulation ratios, defects were successfully detected through an MSPC chart from NIR spectra, highlighting the sensitivity of NIR-based analyses. In batches with intentional changes in the process variable settings, deviations were identified by the MSPC of the process variables. This paper presents a robust framework for ensuring the consistent quality of drug products and process performance in continuous manufacturing by leveraging the complementary strengths of NIR and process variable monitoring for MSPC. The proposed method addresses the limitations of traditional batch monitoring and offers improved sensitivity in variation detection.
{"title":"Quality and process-performance monitoring in the pharmaceutical continuous manufacturing of oral solid dosage forms with statistical control from process variables and near-infrared spectroscopy","authors":"Toshiki Yamaoka , Hideo Takashima , Kohei Tahara","doi":"10.1016/j.apt.2025.105075","DOIUrl":"10.1016/j.apt.2025.105075","url":null,"abstract":"<div><div>We developed a statistical control approach combining process variables and near-infrared (NIR) spectroscopy to detect deviations in the continuous manufacturing of oral solid dosage forms. Multivariate statistical process control (MSPC) models were independently developed for process variables during wet granulation and drying, as well as for NIR spectral data. Data obtained from a laboratory-scale continuous manufacturing unit (ConsiGma™-1) were used to construct principal component analysis based MSPC models, enabling identification of abnormal batches via calculated Hotelling’s T<sup>2</sup> and Q statistics. The combined use of NIR and process variable monitoring for the MSPC technique enabled the accurate detection of process deviations and product quality defects, demonstrating its effectiveness. In batches with altered formulation ratios, defects were successfully detected through an MSPC chart from NIR spectra, highlighting the sensitivity of NIR-based analyses. In batches with intentional changes in the process variable settings, deviations were identified by the MSPC of the process variables. This paper presents a robust framework for ensuring the consistent quality of drug products and process performance in continuous manufacturing by leveraging the complementary strengths of NIR and process variable monitoring for MSPC. The proposed method addresses the limitations of traditional batch monitoring and offers improved sensitivity in variation detection.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 11","pages":"Article 105075"},"PeriodicalIF":4.2,"publicationDate":"2025-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145262439","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}
Pub Date : 2025-10-09DOI: 10.1016/j.apt.2025.105074
Xu Wang , Libing Jin , Jingjin Zhang , Doudou Zhu , Qiang Wu
Squat silos have the advantages of high space utilization, and good ventilation, which are of great significance to guarantee food security. In this research, a mathematical model was constructed using the discrete element method, and a comparison with Janssen’s theory corroborated its validity. Through the established numerical model, the effects of the rolling friction coefficient between particles (RFp) and rolling friction coefficient between particles with silo wall (RFw) during the discharging were investigated, and the kinetic behaviors of particles as well as the dynamic response between silo and particles were analyzed. The results show that: (1) RFp has a greater influence on the discharging behavior, and the coupling of RFp and RFw significantly affects the discharging process. The engineering recommendation for the overpressure coefficient of squat silo is 3.5. (2) The variations in RFp and RFw influence the uniformity of particle flow and have a significant impact on the vertical contact stress between particles. (3) RFp and RFw contribute to an increase in the rotational kinetic energy and angular velocity of particles while reducing velocity fluctuations. These findings contribute to a comprehensive understanding of the discharging performance of Squat silos and provide valuable insights into optimizing their behavior.
{"title":"Rolling friction coefficients: a key factor in the dynamic response of squat silos subjected to grain central discharge","authors":"Xu Wang , Libing Jin , Jingjin Zhang , Doudou Zhu , Qiang Wu","doi":"10.1016/j.apt.2025.105074","DOIUrl":"10.1016/j.apt.2025.105074","url":null,"abstract":"<div><div>Squat silos have the advantages of high space utilization, and good ventilation, which are of great significance to guarantee food security. In this research, a mathematical model was constructed using the discrete element method, and a comparison with Janssen’s theory corroborated its validity. Through the established numerical model, the effects of the rolling friction coefficient between particles (RFp) and rolling friction coefficient between particles with silo wall (RFw) during the discharging were investigated, and the kinetic behaviors of particles as well as the dynamic response between silo and particles were analyzed. The results show that: (1) RFp has a greater influence on the discharging behavior, and the coupling of RFp and RFw significantly affects the discharging process. The engineering recommendation for the overpressure coefficient of squat silo is 3.5. (2) The variations in RFp and RFw influence the uniformity of particle flow and have a significant impact on the vertical contact stress between particles. (3) RFp and RFw contribute to an increase in the rotational kinetic energy and angular velocity of particles while reducing velocity fluctuations. These findings contribute to a comprehensive understanding of the discharging performance of Squat silos and provide valuable insights into optimizing their behavior.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 11","pages":"Article 105074"},"PeriodicalIF":4.2,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145262440","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}
Pub Date : 2025-10-09DOI: 10.1016/j.apt.2025.105077
Lei Jiang , Yuxin Zhao , Zhenjiang Zhao , Tao Guo , Ling Bai , Ling Zhou
Solid-liquid two-phase flow pumps play a critical role in engineering field, and understanding the particle flow mechanism is fundamental to improving the performance. In this study, Computational Fluid Dynamics-Discrete Element Method (CFD-DEM) numerical simulation was employed to analyze the flow field distribution and particle flow in the pump under different inlet flow rates (IFR). High-speed photography visualization experiments and energy characteristic experiments were conducted to verify the accuracy of the numerical simulation. The results show that at a constant particle volume fraction, an increase in IFR enhances the liquid flow angle, which causes the inlet flow to promote the low-velocity vortex at the head of the blade pressure surface. The IFR is positively associated with the rotational velocity of the particles in the impeller. A higher IFR intensifies the forces acting on the particles; the pressure gradient force on the particles is strongest in the impeller, and the normal force is strongest in the volute. The distribution of the force on the particles in the volute exhibits a similar trend, initially decreasing and then stabilizing. This study offers theoretical insights for the solid–liquid two-phase flow in centrifugal pumps.
{"title":"CFD-DEM simulation and experimental study of particle dynamics in a solid-liquid two-phase centrifugal pump","authors":"Lei Jiang , Yuxin Zhao , Zhenjiang Zhao , Tao Guo , Ling Bai , Ling Zhou","doi":"10.1016/j.apt.2025.105077","DOIUrl":"10.1016/j.apt.2025.105077","url":null,"abstract":"<div><div>Solid-liquid two-phase flow pumps play a critical role in engineering field, and understanding the particle flow mechanism is fundamental to improving the performance. In this study, Computational Fluid Dynamics-Discrete Element Method (CFD-DEM) numerical simulation was employed to analyze the flow field distribution and particle flow in the pump under different inlet flow rates (IFR). High-speed photography visualization experiments and energy characteristic experiments were conducted to verify the accuracy of the numerical simulation. The results show that at a constant particle volume fraction, an increase in IFR enhances the liquid flow angle, which causes the inlet flow to promote the low-velocity vortex at the head of the blade pressure surface. The IFR is positively associated with the rotational velocity of the particles in the impeller. A higher IFR intensifies the forces acting on the particles; the pressure gradient force on the particles is strongest in the impeller, and the normal force is strongest in the volute. The distribution of the force on the particles in the volute exhibits a similar trend, initially decreasing and then stabilizing. This study offers theoretical insights for the solid–liquid two-phase flow in centrifugal pumps.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 11","pages":"Article 105077"},"PeriodicalIF":4.2,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145262441","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}
Pub Date : 2025-09-27DOI: 10.1016/j.apt.2025.105073
Min Ji Lee , Haeun Son , Suyoung Kim , Sung Won Kim
This study investigates the entrainment characteristics of iron ore particles under varying gas properties, considering the low-density gas conditions of reducing agents in a fluidized bed for hydrogen-based iron reduction. Experiments were conducted in a fluidized bed (0.05 m I.D × 3.05 m high) using iron ore particles (125–2800 μm) and gases of different densities. Iron ore particles were characterized by a high fraction of fines smaller than 45 μm (F45), which adhered to the surfaces of primary coarse particles. The laser diffraction method effectively evaluated the particle size distribution of iron ore. The total entrainment rate (Gs) increased with gas velocity (Ug) and gas density (ρg), with the increase being more pronounced at higher F45. The entrainment of coarse particles with terminal velocities (Ut) higher than a given Ug was affected by the entrained flow of fine particles. Gs consistently exhibited an exponential increase with increasing Ug/Ut across varying Ug and gas properties. The size ratio of critical to coarse particles (dcrit/dp,coarse) was identified as a physical factor to interpret the entrainment of adhered fines from coarse particles. A correlation was proposed to predict Gs by incorporating Ug/Ut, Archimedes number, and particle characteristics such as F45 and dcrit/dp,coarse.
考虑氢基铁还原流化床还原剂的低密度气体条件,研究了不同气体性质下铁矿颗粒的夹带特性。采用粒度为125 ~ 2800 μm的铁矿颗粒和不同密度的气体,在直径0.05 m ×高3.05 m的流化床中进行了实验。铁矿颗粒的特点是含有大量小于45 μm (F45)的细小颗粒,这些细小颗粒粘附在原生粗颗粒表面。激光衍射法有效地评价了铁矿的粒度分布,总夹带速率(Gs)随气速(Ug)和气密度(ρg)的增大而增大,且在F45较高时增大更为明显。终端速度(Ut)大于给定Ug的粗颗粒的夹带受细颗粒夹带流的影响。在不同的Ug和气体性质下,Gs随Ug/Ut的增加呈指数增长。临界颗粒与粗颗粒的尺寸比(dcrit/dp,粗)被确定为解释粗颗粒粘附细颗粒夹带的物理因素。结合Ug/Ut、阿基米德数、F45、dcrit/dp、coarse等粒子特征,提出了预测Gs的相关性。
{"title":"Entrainment behavior of iron ore particles in a fluidized bed under varying gas properties","authors":"Min Ji Lee , Haeun Son , Suyoung Kim , Sung Won Kim","doi":"10.1016/j.apt.2025.105073","DOIUrl":"10.1016/j.apt.2025.105073","url":null,"abstract":"<div><div>This study investigates the entrainment characteristics of iron ore particles under varying gas properties, considering the low-density gas conditions of reducing agents in a fluidized bed for hydrogen-based iron reduction. Experiments were conducted in a fluidized bed (0.05 m I.D × 3.05 m high) using iron ore particles (125–2800 μm) and gases of different densities. Iron ore particles were characterized by a high fraction of fines smaller than 45 μm (F<sub>45</sub>), which adhered to the surfaces of primary coarse particles. The laser diffraction method effectively evaluated the particle size distribution of iron ore. The total entrainment rate (G<sub>s</sub>) increased with gas velocity (U<sub>g</sub>) and gas density (ρ<sub>g</sub>), with the increase being more pronounced at higher F<sub>45</sub>. The entrainment of coarse particles with terminal velocities (U<sub>t</sub>) higher than a given U<sub>g</sub> was affected by the entrained flow of fine particles. G<sub>s</sub> consistently exhibited an exponential increase with increasing U<sub>g</sub>/U<sub>t</sub> across varying U<sub>g</sub> and gas properties. The size ratio of critical to coarse particles (d<sub>crit</sub>/d<sub>p,coarse</sub>) was identified as a physical factor to interpret the entrainment of adhered fines from coarse particles. A correlation was proposed to predict G<sub>s</sub> by incorporating U<sub>g</sub>/U<sub>t</sub>, Archimedes number, and particle characteristics such as F<sub>45</sub> and d<sub>crit</sub>/d<sub>p,coarse</sub>.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 11","pages":"Article 105073"},"PeriodicalIF":4.2,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145216933","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}
Pub Date : 2025-09-27DOI: 10.1016/j.apt.2025.105071
Xinxin Li , Xiao Liu , Lei Lu , Xiaokai Niu , Zhitian Xie , Jianrong Song , Ziming Wang , Suping Cui
Conventional superplasticizers are generally applicable to Portland cement but not to sulfoaluminate cement (SAC). In this study, superplasticizers with different ratios of carboxyl to phosphate, which were used acrylic acid (AA), 2-methacryloyloxyethyl phosphate (MOEP), and isobutylene polyethylene glycol (HPEG) as monomers, were synthesized dedicated to SAC. The initial fluidity and fluidity retention of SAC paste containing superplasticizer were tested, and the coadsorption behavior of phosphate and carboxyl groups of superplasticizer on SAC particles was also evaluated. The results showed that PC35PP65 and PC65PP35 exhibited higher fluidity of SAC paste, greater adsorption capacity (2.74 and 5.17 times greater than that of PC100, respectively), higher adsorption binding energy, and stronger complexation with Ca2+ and Al3+. The adsorbed layer thickness and hydrodynamic radius (Rh) increased with the increase in phosphate group substitution. Moreover, Langmuir, Freundlich, and Temkin adsorption models and kinetic fitting, as well as complexing index, were introduced to clarify the coadsorption mechanism and the synergistic adsorption of carboxyl and phosphate groups on the SAC surface. The aim of this study is to reveal the coadsorption behavior of phosphate and carboxyl groups in superplasticizer on SAC particles and their synergistic effect, which can provide guidance for further research on SAC superplasticizers.
{"title":"Coadsorption behavior of phosphate and carboxyl groups in superplasticizer on sulfoaluminate cement particles","authors":"Xinxin Li , Xiao Liu , Lei Lu , Xiaokai Niu , Zhitian Xie , Jianrong Song , Ziming Wang , Suping Cui","doi":"10.1016/j.apt.2025.105071","DOIUrl":"10.1016/j.apt.2025.105071","url":null,"abstract":"<div><div>Conventional superplasticizers are generally applicable to Portland cement but not to sulfoaluminate cement (SAC). In this study, superplasticizers with different ratios of carboxyl to phosphate, which were used acrylic acid (AA), 2-methacryloyloxyethyl phosphate (MOEP), and isobutylene polyethylene glycol (HPEG) as monomers, were synthesized dedicated to SAC. The initial fluidity and fluidity retention of SAC paste containing superplasticizer were tested, and the coadsorption behavior of phosphate and carboxyl groups of superplasticizer on SAC particles was also evaluated. The results showed that PC35PP65 and PC65PP35 exhibited higher fluidity of SAC paste, greater adsorption capacity (2.74 and 5.17 times greater than that of PC100, respectively), higher adsorption binding energy, and stronger complexation with Ca<sup>2+</sup> and Al<sup>3+</sup>. The adsorbed layer thickness and hydrodynamic radius (R<sub>h</sub>) increased with the increase in phosphate group substitution. Moreover, Langmuir, Freundlich, and Temkin adsorption models and kinetic fitting, as well as complexing index, were introduced to clarify the coadsorption mechanism and the synergistic adsorption of carboxyl and phosphate groups on the SAC surface. The aim of this study is to reveal the coadsorption behavior of phosphate and carboxyl groups in superplasticizer on SAC particles and their synergistic effect, which can provide guidance for further research on SAC superplasticizers.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 11","pages":"Article 105071"},"PeriodicalIF":4.2,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145155355","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}