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Influence of Recycled Concrete Fine Powder on Durability of Cement Mortar
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作者 Yadong Bian Xuan Qiu +2 位作者 Jihui Zhao Zhong Li Jiana Ouyang 《Fluid Dynamics & Materials Processing》 EI 2024年第1期45-58,共14页
In this paper,the durability of cement mortar prepared with a recycled-concrete fine powder(RFP)was examined;including the analysis of a variety of aspects,such as the carbonization,sulfate attack and chloride ion ero... In this paper,the durability of cement mortar prepared with a recycled-concrete fine powder(RFP)was examined;including the analysis of a variety of aspects,such as the carbonization,sulfate attack and chloride ion erosion resistance.The results indicate that the influence of RFP on these three aspects is different.The carbonization depth after 30 days and the chloride diffusion coefficient of mortar containing 10%RFP decreased by 13.3%and 28.19%.With a further increase in the RFP content,interconnected pores formed between the RFP particles,leading to an acceleration of the penetration rate of CO_(2)and Cl^(−).When the RFP content was less than 50%,the corrosion resistance coefficient of the compressive strength of the mortar was 0.84-1.05 after 90 days of sulfate attack.But the expansion and cracking of the mortar was effectively alleviated due to decrease of the gypsum production.Scanning electron microscope(SEM)analysis has confirmed that 10%RFP contributes to the formation of a dense microstructure in the cement mortar. 展开更多
关键词 Recycled concrete fine powder cement mortar CARBONIZATION SULFATE chloride ion DURABILITY
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Effects of Curing Systems on Properties of High Volume Fine Mineral Powder RPC and Appearance of Hydrates 被引量:6
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作者 刘娟红 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第4期619-623,共5页
The effects of different curing systems on the properties of high volume fine mineral powder RPC (reactive powder concrete) and the appearances of hydrates were studied. The experimental results show that dry-heatin... The effects of different curing systems on the properties of high volume fine mineral powder RPC (reactive powder concrete) and the appearances of hydrates were studied. The experimental results show that dry-heating curing promotes the development of pozzolanic reactivity of fine mineral powder; due to low cement content, 0.20 water-bind ratio and high reactive fine mineral powder content, the strength of RPC increases by around 200% after steam curing and subsequent dry-heating curing. Scanning electron microscopy and energy spectrum diagram showed that: after the high volume fine mineral powder RPC with 0.16 water-bind ratio underwent steam curing and dry-heating curing, there was no significant change in the appearance of hydrates; after the RPC with 0.20 water-bind ratio, the cement content of 150 kg/m3 and more steel slag powder underwent dry-heating curing, there was a certain change in the appearance of C-S-H, the structure of gel was more compact and was uniformly distributed, and the Ca/Si of C-S-H gel decreased from 1.41 to around 1.20. 展开更多
关键词 curing system high volume fine mineral powder RPC appearance of hydrates
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Experimental investigation on micro-dynamic behavior of gas explosion suppression with SiO_2 fine powders 被引量:9
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作者 Xianfeng Chen,~(1,2,a)) Yin Zhang,~1 Qingming Zhang,~2 Shaofeng Ren,~1 and Jianxing Wu~1 1)School of Natural Resources and Environmental Engineering,Wuhan University of Technology, Wuhan 430070,China 2)State Key Laboratory of Explosion Science and Technology,Beijing Institute of Technology, Beijing 100081,China 《Theoretical & Applied Mechanics Letters》 CAS 2011年第3期58-61,共4页
To study the effect of inert dust on gas explosion suppression mechanism,SiO_2 fine powders were sprayed to suppress premixed CH_4-Air gas explosion in a 20 L spherical experimental system.In the experiment,high speed... To study the effect of inert dust on gas explosion suppression mechanism,SiO_2 fine powders were sprayed to suppress premixed CH_4-Air gas explosion in a 20 L spherical experimental system.In the experiment,high speed schlieren image system was adopted to record explosion flame propagation behaviors,meanwhile,pressure transducers and ion current probes were used to clearly record the explosion flame dynamic characteristics.The experimental results show that the SiO_2 fine powders suppressed evidently the gas explosion flame,and reduced the peak value of pressure and flame speed by more than 40%.The ion current result shows that the SiO_2 super fine powders were easy to contact with and absorb free radicals near the combustion reaction region,which greatly reduced the combustion reaction intensity,and in turn influenced the flame propagation and pressure rising. 展开更多
关键词 fine powder gas explosion explosion suppression reaction mechanism
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Influence of MnO_2 Mineralizer on the Crystal Structure,Properties of SiC Kiln Furniture Bonded with Fine Silicon Powder 被引量:4
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作者 RUAN Yu-Zhong WU Wan-Guo +2 位作者 YU Yan ZHAN Hong-Bing LIN Chun-Ying(Department of Chemlcal Engineering, Fuzhou University, 350002) 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1997年第5期397-402,共6页
The properties of SiC kiln furniture bonded with fine silicon powderare related to the bonder’s crystal structure. At high temperature, it will crystallize ina-cristobalite with great bulk effect. MnO2 mineralizer ca... The properties of SiC kiln furniture bonded with fine silicon powderare related to the bonder’s crystal structure. At high temperature, it will crystallize ina-cristobalite with great bulk effect. MnO2 mineralizer can make a-cristobalite convertto a-tridymite whose bulk effect is small. The crystal structure and its amount were investigated with XRD technique. The influence of different amounts of MnO2 on thecrystal structure and polycrystal transformation, and that of crystal structure on theproperties of kiln furniture were studied. The best proportion of MnO2 added was determined to be 2.0%. 展开更多
关键词 MnO_2 mineralizer fine silicon powder SiC kiln furniture
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Commercial Processof Bi-based 2212 Single Phase Superconducting Precursor Powder 被引量:1
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作者 华志强 李月南 郑明辉 《Rare Metals》 SCIE EI CAS CSCD 1999年第1期61-65,共5页
Laying emphasis on the preparation of Bi based 2212 single phase superconducting powder, some technological parameters, which effect the single phase degree and uniformity of powder, such as prebaking, sintering and ... Laying emphasis on the preparation of Bi based 2212 single phase superconducting powder, some technological parameters, which effect the single phase degree and uniformity of powder, such as prebaking, sintering and heat treatment were investigated and discussed. Ensuring the powder T c at 83~85 K, the crucial impurity carbon was reduced to 0.03% and less. Adopting uncommon technique made the powder size to micrometer level, meanwhile the superconducting performance of the powder was unchanged. The fine superconducting powder was characterized. This process of Bi based 2212 superconducting powder was successful. 展开更多
关键词 Bi 2212 phase Superconducting fine powder Bi based superconductor
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AGGREGATE STRUCTURE OF FINE POWDER AND COMPACTION PROCESS
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作者 王炳华 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1993年第4期29-34,共6页
Compacting process of fine powder is greatly affected by the aggregate structure of particles. According to the experiment in which several kinds of silicon nitrides in different partical shape and size were compacted... Compacting process of fine powder is greatly affected by the aggregate structure of particles. According to the experiment in which several kinds of silicon nitrides in different partical shape and size were compacted in uniaxialorientation, it is found that the volume compacting rate offorming body differs with the pressure. The aggregatestructure of each sample A, B or C was estimated by applying Cooper's equation to the analysis of the compacting process of each sample 展开更多
关键词 fine powder aggregate structure compaction process packing process volume compaction rate
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Study on the Durability of Recycled Powder Concrete against Sulfate Attack under Partial Immersion Condition
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作者 Hualei Bai Ying Li Dahu Dai 《Journal of Renewable Materials》 SCIE EI 2022年第11期3059-3078,共20页
In order to make full use of waste recycled fine powder(RFP)in concrete and achieve the goal of carbon neutrality in the concrete industry,the durability of sulfate resistance is an important aspect of evaluating the ... In order to make full use of waste recycled fine powder(RFP)in concrete and achieve the goal of carbon neutrality in the concrete industry,the durability of sulfate resistance is an important aspect of evaluating the performance of recycled powder concrete(RPC).Therefore,the durability of RPC under partial sulfate immersion was studied to provide theoretical guidance for understanding the erosion mechanism of RPC.The compressive strength,mass loss,and microstructure change patterns of RPC under partial immersion of 5%Na2SO4 and MgSO4 solutions were analyzed by cubic compressive strength,mass loss rate,SEM-EDS,and XRD.The results showed that the surface crystalline matter of concrete in Na2SO4 solution was mainly white powders,and that of concrete in MgSO4 solution was mainly transparent paste,both of which had a little spalling on the outer surface of the concrete.The compressive strength and mass loss rate of concrete with 20%RFP was relatively good,indicating that concrete with 20%RFP had better durability against sulfate.The compressive strength of the lower part of the concrete partially immersed in Na2SO4 solution was higher than that of the upper part and the strength of the lower part of RPC-2 was 3.11%higher than the upper part at 180 d;The pattern was reversed in the MgSO4 solution,where the strength of the lower part of RPC-2 was 19.74%lower than the upper part at 180 d.Microscopic analysis showed that the hydration products of RPC were mainly gypsum and ettringite,while the RPC produced more hydration products with the promotion of magnesium ion in the MgSO4 solution.The higher the replacement rate of RFP,the more frequent the gypsum-type failures in the concrete. 展开更多
关键词 Recycled powder concrete recycled fine powder sulfate resistance compressive strength
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Influence and Characterization of Acidity on Fine Silicon Powder Immobilized Photocatalyst
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作者 赖寿莲 陈清松 李晓燕 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第7期819-823,共5页
TiO2 photocatalyst was supported with tetrabutyl titanate sol as precursor and fine silicon powder obtained from ferroalloys factory as carder to discuss the influence of pH value of gel precursor on microstructure an... TiO2 photocatalyst was supported with tetrabutyl titanate sol as precursor and fine silicon powder obtained from ferroalloys factory as carder to discuss the influence of pH value of gel precursor on microstructure and activity of photocatalyst in the process of synthesizing nano-TiO2 by using sol-gel method, the purpose of which is to provide fundamental data for the recycle of photocatalytic material. Under the irradiation of ultraviolet light, the photocatalytic degradation rate of methyl orange solution was used to characterize the photocatalytic activity of the sample. The specific surface area of the sample was tested by N2 desorption method, crystal form of TiO2 was analyzed by X-ray powder diffraction, and the microtopography of the sample was observed by scanning electron microscopy. The experimental results showed that the acidity of gel precursor could greatly affect the specific surface area and photocatalytic activity of the photocatalyst, and the optimum pH value of the precursor was determined as 2.0, and at this time the specific surface area of photocatalyst could reach 34.0 m^2/g. In the sample, the proporticn of anatase to rutile is 7:3, which makes l0 mg·L^-1 methyl orange solution fade after irradiation by 15W ultraviolet light for 24 h, and the degradation rate might be up to 98.1%. 展开更多
关键词 fine silicon powder TiO2 photocatalyst ACIDITY support
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Studies on Acid Leaching Methods for Fine Metal Powder Production
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作者 Rajagopalan P K and Krishnan T S Material Processing Division, Bhabha Atomic Research Centre, Mumbai 400 085, India 《Rare Metals》 SCIE EI CAS CSCD 1998年第3期44-47,共4页
Two different processes (i) alloying followed by selective leaching of alloying constituent and (ii) controlled chemical attack of oversize powder stock were studied in some detail to assess their suitability for meta... Two different processes (i) alloying followed by selective leaching of alloying constituent and (ii) controlled chemical attack of oversize powder stock were studied in some detail to assess their suitability for metal powder production. In a typical series of experiments on the alloying process, titanium, zirconium and nickel were alloyed with aluminium. The sample was then leached out with acid to yield the metals in powder form. The metal powders generally had a particle size spread in the range of <5 μm. The acid concentration and contact time were varied and both have influences on particle size of the final product. In the second process involving chemical attack of coarse powder, it is shown by taking the example of nickel that a range of particle size could be generated through close control of acid concentration and contact time. 展开更多
关键词 Fine metal powder In situ alloying Selective leaching
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Preparation of Strontium Bismuth Tantalum (SBT) Fine Powder by Sol-Gel Process Using Bismuth Subnitrate as Bismuth Source
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作者 Wen WANG Yu ZHOU +1 位作者 Sheng CHEN Feng YE and Dechang JIA School of Materials Science and Engineering, P.O.Box 433, Harbin institute of Technology, Harbin 150001, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2001年第1期25-26,共2页
Strontium bismuth tantalum (SBT) fine power was prepared by Sol-Gel method. Pentaethoxy tantalum, strontium acetate and bismuth subnitrate were used as raw materials, and were dissolved in proper order in ethylene gl... Strontium bismuth tantalum (SBT) fine power was prepared by Sol-Gel method. Pentaethoxy tantalum, strontium acetate and bismuth subnitrate were used as raw materials, and were dissolved in proper order in ethylene glycol to form transparent sol. The mixed precursor was dried at 80℃ and annealed at 800℃ for 1 h. Crystallized nanometer sized SBT fine powder was obtained and characterized by XRD. 展开更多
关键词 SBT Preparation of Strontium Bismuth Tantalum Ta Fine powder by Sol-Gel Process Using Bismuth Subnitrate as Bismuth Source
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Comparative Study on Super Fine Mesophase Powder and MCMB Used to Manufacture High-Density Isotropic Carbon Bulks
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作者 LI Tong-qi HU Zi-jun +2 位作者 WANG Jun-shan GUO Yu-ming WANG Cheng-yang 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2006年第B12期187-191,共5页
Mesocarbon microbeads (MCMB) and super fine mesophase powder (SFMP) were prepared firstly from a coal tar pitch and then hot-condensed into high-density isotropic carbon (HDIC) bulks under 160 MPa and finally si... Mesocarbon microbeads (MCMB) and super fine mesophase powder (SFMP) were prepared firstly from a coal tar pitch and then hot-condensed into high-density isotropic carbon (HDIC) bulks under 160 MPa and finally sintered at 1 000 ℃. By analyzing the thermogravimetric behavior of the MCMB and SFMP powders, their volume shrinkage and weight loss during sintering and the bulk density and flexural strengths of their sintered bulks, it was found that the smaller sizes and the richer β-resin contents of SFMP ha)re facilitated formation of sintered bulks with more compact isotropic structure and higher flexural strengths than MCMB. Because of the filling and bonding effects of SFMP on MCMB bulks, addition of SFMP, albeit a little, can greatly increase the flexural strengths of sintered bulks of MCMB. However, adding MCMB, even a slight amount, into SFMP can severely impair the flexural strength of sintered bulks. This might be attributed to both the crack initiation along the boundaries between MCMB and SFMP and the formation of layered texture of MCMB sphere. 展开更多
关键词 mesocarbon microbeads super fine mesophase powder (SFMP) high-density isotropic carbon (HDIC) bulk sintered bulk
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Preliminary research on movement regularity of fine carbon fiber powder injected into intracrania of mice
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《Chinese Journal of Biomedical Engineering(English Edition)》 2001年第3期133-134,共2页
关键词 Preliminary research on movement regularity of fine carbon fiber powder injected into intracrania of mice
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Researches on the Structure and Properties of Mullite Solid Solution Made from Industrial Waste 被引量:4
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作者 RUAN Yu-Zhong YU Yan WU Ren-Ping 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第8期965-970,共6页
The waste slag from aluminum profile factory and silicon fine powder from ferroalloy factory were utilized as the main raw materials to synthesize mullite solid solution Al4+2xSi2-xO10-x/2, whose defect formation mec... The waste slag from aluminum profile factory and silicon fine powder from ferroalloy factory were utilized as the main raw materials to synthesize mullite solid solution Al4+2xSi2-xO10-x/2, whose defect formation mechanism, crystalline phase composition, crystal cell parameters, microstructures and morphologies were characterized in detail by XRD and SEM. The results show that because of the ultrafine particle size of the materials, the content of mullite solid solution synthesized by this method is higher than that by regular method. Keywords: waste slag from aluminum factory, silicon fine powder, mullite, solid solution 展开更多
关键词 waste slag from aluminum factory silicon fine powder MULLITE solid solution
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Reduction of 1-3 mm iron ore by H_2 in a fluidized bed 被引量:1
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作者 Jian-ming Pang Pei-min Guo Pei Zhao Chao-zhen Cao Ding-guo Zhao Duo-gang Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2009年第6期620-625,共6页
The reduction of 1-3 mm fine powder of iron ore by H2 was conducted in a lab-fabricated kg class high temperature fluidized bed. The results show that the differential pressure in the fluidized bed, which has small fl... The reduction of 1-3 mm fine powder of iron ore by H2 was conducted in a lab-fabricated kg class high temperature fluidized bed. The results show that the differential pressure in the fluidized bed, which has small fluctuation with time, increases with the increase of gas flowing velocity. The utilization ratio of gas decreases when the reaction lasts longer time indicating that the reaction is faster at the beginning of reduction and becomes slower in the latter process. The higher the reaction temperature is, the higher the utilization ratio of gas is, but the difference of utilization ratio among the different temperatures becomes smaller with time. The utilization ratio of gas and the metallization ratio can reach 9% and 84% respectively at 750℃ for 20 min, which shows the reduction reaction by H2 is very fast. The increase of metallization ratio with gas velocity performs quite good linearity, which shows that a higher velocity of reducing gas can be used to improve the productivity of the reactor when H2 is used as reducing gas. With the increase of charge height, the metallization ratio decreases, but the utilization ratio of gas increases. The reaction temperature can be reduced to 700-750℃ from 800-850℃ when H2 is used as reducing gas. 展开更多
关键词 HYDROGEN fluidized bed fine powder iron ore IRONMAKING reduction reaction
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The Influence of an Acoustic Field on the Bed Expansion of Fine Particles
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作者 Akash M. Langde R.L.Sonolikar 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第4期649-655,共7页
Fine particles are difficult to fluidize due to strong interparticle attraction.An attempt has been made to study the bed expansion of silica gel(dp=25μm) powder in presence of an acoustic field.A 135 mm diameter flu... Fine particles are difficult to fluidize due to strong interparticle attraction.An attempt has been made to study the bed expansion of silica gel(dp=25μm) powder in presence of an acoustic field.A 135 mm diameter fluidized bed activated by an acoustic field with sound intensity up to 145 dB and frequency from 90 Hz to 170 Hz was studied.The effects of sound pressure level,sound frequency and particle loading on the bed expansion were investigated.Experimental results showed that,bed expansion was good in presence of acoustic field of particular frequency.In addition,it was observed that in presence of acoustic field the bed collapses slowly. 展开更多
关键词 acoustic field FREQUENCY VIBRATION fluidized bed fine powder EXPANSION
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Improvement of Cement Strength by Induction Method
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作者 杨力远 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2004年第2期79-81,共3页
The induction method of improving the strength of Portland cement by adding fine slag powder,high aluminate component and hydrated paste was investigated through determining the physical properties,hydration heat and ... The induction method of improving the strength of Portland cement by adding fine slag powder,high aluminate component and hydrated paste was investigated through determining the physical properties,hydration heat and pore size distribution,and its mechanism was discussed.The experimental results reveal that a certain content of high aluminate component,fine slag powder and hydrated paste can improve remarkably the strength of Portland cement. 展开更多
关键词 fine slag powder ALUMINATE hydrated paste compressive strength
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FLUIDIZATION OF FINE POWDERS IN FLUIDIZED BEDS WITH AN UPWARD OR A DOWNWARD AIR JET 被引量:5
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作者 RuoyuHong JianminDing HongzhongLi 《China Particuology》 SCIE EI CAS CSCD 2005年第3期181-186,共6页
The hydrodynamic behavior of fine powders in jet-fluidized beds was studiednumerically and experimentally. The starting point of numerical simulation was the generalizedNavier-Stokes (N-S) equations for the gas and so... The hydrodynamic behavior of fine powders in jet-fluidized beds was studiednumerically and experimentally. The starting point of numerical simulation was the generalizedNavier-Stokes (N-S) equations for the gas and solids phases. The κ-ε turbulence model was used forhigh-speed gas jets in fluidized beds. Computation shows that a suitable turbulence model isnecessary to obtain agreement between the simulation and literature experimental data for ahigh-speed gas jet. The model was applied to simulating the fluidization of fine powders influidized beds with an upward or a downward air jet. An empirical cohesion model was obtained bycorrelating the cohesive force between fine particles using a cohetester. The cohesion model wasembedded into the two-fluid model to simulate the fluidization of fine powders in two-dimensional(2-D) beds. To study the fluidization behavior of fine and cohesive powders with a downward jet,experiments were performed in a 2-D bed. Agreement between the computed time-averaged porosity andmeasured data was obtained. With an upward jet in the bed center, the measured and computedporosities show a dilute central core, especially at very high jet velocities. Based on ourexperiments and computations, a downward jet located inside the bed is recommended to achieve bettermixing and contacting of gas and solids. 展开更多
关键词 FLUIDIZATION JET fine powder two-fluid model
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Low-velocity pneumatic conveying in horizontal pipe for coarse particles and fine powders 被引量:9
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作者 Yuji Tomita Vijay Kumar Agarwal +1 位作者 Hiroyuki Asou Katsuya Funatsu 《Particuology》 SCIE EI CAS CSCD 2008年第5期316-321,共6页
First, the characteristics of low-velocity conveying of particles having different hardness are experimentally investigated in a horizontal pipeline in terms of flow pattern and pressure drop to show that the slug flo... First, the characteristics of low-velocity conveying of particles having different hardness are experimentally investigated in a horizontal pipeline in terms of flow pattern and pressure drop to show that the slug flow can be classified into two types depending on the settling of particles along the pipeline, and the period is small for slug flow without the settled layer, which is called solitary slug flow. The pressure drop for soft particles is shown to be larger than that for hard particles. Then, experimental results are presented on horizontal fluidized-bed conveying of fine powders to show that air release from the top surface of the conveying channel is an imnortant factor for high mass flow rate of particles. 展开更多
关键词 Low-velocity conveying Slug flow Soft particle Horizontal fluidized-bed conveying Fine powder
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Ultrasound-assisted microfeeding of fine powders 被引量:2
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作者 Xuesong Lu Shoufeng Yang Julian R.G. Evans 《Particuology》 SCIE EI CAS CSCD 2008年第1期2-8,共7页
Ultrasonic microfeeding of powders is a new and promising method for use in solid freeforming and pharmaceutical dosing. In this work, computer-controlled microfeeding systems using ultrasonic vibration of a capillary... Ultrasonic microfeeding of powders is a new and promising method for use in solid freeforming and pharmaceutical dosing. In this work, computer-controlled microfeeding systems using ultrasonic vibration of a capillary were built. A wide range of controlled, stable rates of flow and switching control were achieved in the acoustic vibration system and uniform powder doses were obtained in the ultrasonic system. Experimental results show that nozzle diameter, transmission fluid depth, waveform, voltage amplitude, frequency and oscillation duration all influence the dose mass. Among these factors, nozzle diameter, voltage amplitude and oscillation duration can be best used to control the dose mass. An artificial neural network (ANN) technique was applied to predict the dose mass. Based on these research results, four types of microfeeding were proposed. 展开更多
关键词 Microfeeding ULTRASOUND Fine powders
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An investigation into flow mode transition and pressure fluctuations for fluidized dense-phase pneumatic conveying of fine powders 被引量:14
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作者 A.Mittal S.S.Mallick P.W.Wypych 《Particuology》 SCIE EI CAS CSCD 2014年第5期187-195,共9页
This paper presents the results of an ongoing investigation into the fluctuations of pressure signals due to solids-gas flows for dense-phase pneumatic conveying of fine powders. Pressure signals were obtained from pr... This paper presents the results of an ongoing investigation into the fluctuations of pressure signals due to solids-gas flows for dense-phase pneumatic conveying of fine powders. Pressure signals were obtained from pressure transducers installed along different locations of a pipeline for the fluidized dense-phase pneumatic conveying of fly ash (median particle diameter 30μm; particle density 2300 kg/m^3; loose- poured bulk density 700 kg/m^3) and white powder (median particle diameter 55 p.m; particle density 1600 kg/m^3 ; loose-poured bulk density 620 kg/m^3) from dilute to fluidized dense-phase. Standard deviation and Shannon entropy were employed to investigate the pressure signal fluctuations. It was found that there is an increase in the values of Shannon entropy and standard deviation for both of the prod- ucts along the flow direction through the straight pipe sections. However, both the Shannon entropy and standard deviation values tend to decrease after the flow through bend(s), This result could be attributed to the deceleration of particles while flowing through the bends, resulting in dampened particle fluctua- tion and turbulence. Lower values of Shannon entropy in the early parts of the pipeline could be due to the non-suspension nature of flow (dense-phase), i.e., there is a higher probability that the particles are concentrated toward the bottom of pipe, compared with dilute-phase or suspension flow (high velocity), where the particles could be expected to be distributed homogenously throughout the pipe bore (as the flow is in suspension). Changes in straight-pipe pneumatic conveying characteristics along the flow direction also indicate a change in the flow regime along the flow. 展开更多
关键词 Fluidized dense-phase Pneumatic conveying Fine powders Shannon entropy Flow transition Particle turbulence
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