{"title":"The effects of thermal properties on the interphase drag of supercritical water-particle flow","authors":"Xiaoyu Li, Bowei Zhang, Yi Li, Hui Jin","doi":"10.1016/j.powtec.2025.120849","DOIUrl":null,"url":null,"abstract":"<div><div>The drag of particle clusters is important for the investigation of fluidized beds, but there is no accurate correlation available. The effects of nonlinear physical properties on the drag of particle clusters in supercritical water (SCW) fluidized beds cannot be overlooked either. This work conducts a simulation investigation on the interphase drag of SCW-particle flow. The results reveal that an increase in density leads to a decrease in the drag coefficient <em>C</em><sub><em>d</em></sub>. This results in a positive correlation between the drag coefficient and particle temperature. The effects of Reynolds number (<em>Re</em>) and void fraction (<em>ε</em>) on the density distribution further influence the normalized drag coefficient <em>C</em>. The distributions of dimensionless velocity and kinetic energy indicate that the conversion rate of pressure potential energy to kinetic energy in SCW is lower than that in constant property flow (CPF). The distributions of <em>C</em><sub><em>d</em></sub> and <em>C</em> of sub-particles show that downstream particles are most influenced by variations in density under different conditions. A model for the effects of nonlinear physical properties is established based on the <em>C</em>. Analysis of the results from CPF reveals that the exponent <em>β</em> in this work is primarily a function of <em>ε</em>. A correlation between the exponent <em>β</em> and <em>ε</em> is established. A drag coefficient model for particle flow in SCW is developed through the coupling of multiple models.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"456 ","pages":"Article 120849"},"PeriodicalIF":4.5000,"publicationDate":"2025-02-25","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/S003259102500244X","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
Abstract
The drag of particle clusters is important for the investigation of fluidized beds, but there is no accurate correlation available. The effects of nonlinear physical properties on the drag of particle clusters in supercritical water (SCW) fluidized beds cannot be overlooked either. This work conducts a simulation investigation on the interphase drag of SCW-particle flow. The results reveal that an increase in density leads to a decrease in the drag coefficient Cd. This results in a positive correlation between the drag coefficient and particle temperature. The effects of Reynolds number (Re) and void fraction (ε) on the density distribution further influence the normalized drag coefficient C. The distributions of dimensionless velocity and kinetic energy indicate that the conversion rate of pressure potential energy to kinetic energy in SCW is lower than that in constant property flow (CPF). The distributions of Cd and C of sub-particles show that downstream particles are most influenced by variations in density under different conditions. A model for the effects of nonlinear physical properties is established based on the C. Analysis of the results from CPF reveals that the exponent β in this work is primarily a function of ε. A correlation between the exponent β and ε is established. A drag coefficient model for particle flow in SCW is developed through the coupling of multiple models.
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.