{"title":"利用叶轮式流变仪分析颗粒流的机械堵塞情况","authors":"Wenbin Xuan , Wenguang Nan","doi":"10.1016/j.powtec.2024.120003","DOIUrl":null,"url":null,"abstract":"<div><p>We simulated the cohesive particle flow in an impeller-based rheometer using Discrete Element Method (DEM), and we focus on the dynamics of particles around the constriction between the blade and its surrounding vessel wall. The results show that mechanical jamming could transiently and intermittently occur in the constriction, but it is limited in a narrow region and short duration. Larger stiffness of particles and lifting flow pattern are more prone to the occurrence of jamming. The scaling law used to speed up the DEM simulation by reducing particle stiffness may fail for particle flow passing through clearance. The mechanical jamming of particles is in low frequency with value <50 Hz and the duration of an individual jamming event is usually <0.04 s. The existence of mechanical jamming is also illustrated by the experiment, where the wear of particle surface is clearly observed with scratches and pits.</p></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":null,"pages":null},"PeriodicalIF":4.5000,"publicationDate":"2024-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Analysis on the mechanical jamming of particle flow using impeller-based rheometer\",\"authors\":\"Wenbin Xuan , Wenguang Nan\",\"doi\":\"10.1016/j.powtec.2024.120003\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>We simulated the cohesive particle flow in an impeller-based rheometer using Discrete Element Method (DEM), and we focus on the dynamics of particles around the constriction between the blade and its surrounding vessel wall. The results show that mechanical jamming could transiently and intermittently occur in the constriction, but it is limited in a narrow region and short duration. Larger stiffness of particles and lifting flow pattern are more prone to the occurrence of jamming. The scaling law used to speed up the DEM simulation by reducing particle stiffness may fail for particle flow passing through clearance. The mechanical jamming of particles is in low frequency with value <50 Hz and the duration of an individual jamming event is usually <0.04 s. The existence of mechanical jamming is also illustrated by the experiment, where the wear of particle surface is clearly observed with scratches and pits.</p></div>\",\"PeriodicalId\":407,\"journal\":{\"name\":\"Powder Technology\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":4.5000,\"publicationDate\":\"2024-06-11\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Powder Technology\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0032591024006466\",\"RegionNum\":2,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"ENGINEERING, CHEMICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Powder Technology","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0032591024006466","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENGINEERING, CHEMICAL","Score":null,"Total":0}
引用次数: 0
摘要
我们使用离散元素法(DEM)模拟了叶轮式流变仪中的粘性粒子流,并重点研究了叶片与其周围容器壁之间的收缩周围的粒子动态。结果表明,机械堵塞可能会在收缩处瞬时和间歇性地发生,但仅限于狭窄区域且持续时间较短。较大的颗粒刚度和抬升流动模式更容易发生卡塞。通过降低颗粒刚度来加快 DEM 模拟速度的缩放定律在颗粒流通过间隙时可能会失效。颗粒的机械堵塞频率较低,为 50 赫兹,单个堵塞事件的持续时间通常为 0.04 秒。
Analysis on the mechanical jamming of particle flow using impeller-based rheometer
We simulated the cohesive particle flow in an impeller-based rheometer using Discrete Element Method (DEM), and we focus on the dynamics of particles around the constriction between the blade and its surrounding vessel wall. The results show that mechanical jamming could transiently and intermittently occur in the constriction, but it is limited in a narrow region and short duration. Larger stiffness of particles and lifting flow pattern are more prone to the occurrence of jamming. The scaling law used to speed up the DEM simulation by reducing particle stiffness may fail for particle flow passing through clearance. The mechanical jamming of particles is in low frequency with value <50 Hz and the duration of an individual jamming event is usually <0.04 s. The existence of mechanical jamming is also illustrated by the experiment, where the wear of particle surface is clearly observed with scratches and pits.
期刊介绍:
Powder Technology is an International Journal on the Science and Technology of Wet and Dry Particulate Systems. Powder Technology publishes papers on all aspects of the formation of particles and their characterisation and on the study of systems containing particulate solids. No limitation is imposed on the size of the particles, which may range from nanometre scale, as in pigments or aerosols, to that of mined or quarried materials. The following list of topics is not intended to be comprehensive, but rather to indicate typical subjects which fall within the scope of the journal's interests:
Formation and synthesis of particles by precipitation and other methods.
Modification of particles by agglomeration, coating, comminution and attrition.
Characterisation of the size, shape, surface area, pore structure and strength of particles and agglomerates (including the origins and effects of inter particle forces).
Packing, failure, flow and permeability of assemblies of particles.
Particle-particle interactions and suspension rheology.
Handling and processing operations such as slurry flow, fluidization, pneumatic conveying.
Interactions between particles and their environment, including delivery of particulate products to the body.
Applications of particle technology in production of pharmaceuticals, chemicals, foods, pigments, structural, and functional materials and in environmental and energy related matters.
For materials-oriented contributions we are looking for articles revealing the effect of particle/powder characteristics (size, morphology and composition, in that order) on material performance or functionality and, ideally, comparison to any industrial standard.