Modelling The Effects of Aggregate Size on Alkali Aggregate Reaction Expansion

This work aims at developing models to predict the potential expansion of concrete containing alkali-reactive aggregates. The paper gives measurements in order to provide experimental data concerning the effect of particle size of an alkali-reactive siliceous limestone on mortar expansion. Results show that no expansion was measured on the mortars using small particles (0.5-1.0 mm) while the particles (1.0–2.0 mm) gave the largest expansions (0.217%). Two models are proposed, the first one studies the correlations between the measured expansions and the size of aggregates, the second one calculates the thickness of the porous zone necessary to take again all the volume of the gel created.

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A correlation to predict the performance characteristics of centrifugal pumps handling slurries

Proceedings of the Institution of Mechanical Engineers Part A Journal of Power and Energy ◽

10.1243/0957650971537060 ◽

1997 ◽

Vol 211 (2) ◽

pp. 147-157 ◽

Cited By ~ 20

Author(s):

K A Kazim ◽

B Maiti ◽

P Chand

Keyword(s):

Experimental Data ◽

Particle Size ◽

Suspended Solids ◽

Reduction Factor ◽

Performance Characteristics ◽

Centrifugal Pumps ◽

Pump Performance ◽

New Correlation ◽

Effect Of Particle Size ◽

The Individual

Centrifugal pumps are being used increasingly for transportation of slurries through pipelines. To design a slurry handling system it is essential to have a knowledge of the effects of suspended solids on the pump performance. A new correlation to predict the head reduction factor for centrifugal pumps handling solids has been developed. This correlation takes into account the individual effect of particle size, particle size distribution, specific gravity and concentration of solids on the centrifugal pump performance characteristics. The range of validity of the correlation has been verified by experiment and by using experimental data available from the literature. The present correlation shows better agreement with the experimental data than existing correlations.

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Inkjet printable silver dispersions: Effect of bimodal particle-size distribution on film formation and electrical conductivity

Journal of Materials Research ◽

10.1557/jmr.2010.0124 ◽

2010 ◽

Vol 25 (5) ◽

pp. 821-827 ◽

Cited By ~ 16

Author(s):

Krishna Balantrapu ◽

Meaghan McMurran ◽

Dan V. Goia

Keyword(s):

Electrical Conductivity ◽

Particle Size ◽

Size Distribution ◽

Film Formation ◽

Small Particles ◽

Silver Films ◽

On Demand ◽

Drop On Demand ◽

Large Particles ◽

Effect Of Particle Size

Inks containing silver nanoparticles of 12 nm, 80 nm, and a 15%/85% mixture of the two sizes were used to evaluate the effect of particle size and size distribution on the electrical properties of sintered films. The silver layers deposited with a “drop-on-demand” inkjet printer were heated at temperatures ranging from 125 to 200 °C. The small particles formed less resistive films at 125 °C, while the larger ones provided better electrical conductivity above 150 °C. The inks containing mixed small and large particles yielded the most conductive silver films over the entire investigated temperature range. A mechanism explaining these results is proposed based on the evolution of film microstructure with temperature.

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Effect of Particle Size on Carbon Nanotube Aggregates Behavior in Dilute Phase of a Fluidized Bed

Processes ◽

10.3390/pr6080121 ◽

2018 ◽

Vol 6 (8) ◽

pp. 121 ◽

Cited By ~ 3

Author(s):

Sung Kim

Keyword(s):

Particle Size ◽

Carbon Nanotube ◽

Fluidized Bed ◽

Laser Sheet ◽

Scale Up ◽

Experimental Parameter ◽

Aggregate Size ◽

Chemical Vapor ◽

Gas Velocity ◽

Effect Of Particle Size

Fluidized bed reactors have been increasingly applied for mass production of Carbon Nanotube (CNT) using catalytic chemical vapor deposition technology. Effect of particle size (dp = 131 μm and 220 μm) on fluidization characteristics and aggregation behavior of the CNT particles have been determined in a fluidized bed for its design and scale-up. The CNT aggregation properties such as size and shape were measured in the dilute phase of a fluidized bed (0.15 m-ID × 2.6 m high) by the laser sheet technique for the visualization. Two CNT particle beds showed different tendency in variations of the aggregates factors with gas velocity due to differences in factors contributing to the aggregate formation. The CNT particles with a larger mean size presented as relatively larger in the aggregate size than the smaller CNT particles at given gas velocities. The aggregates from the large CNT particles showed a sharp increase in the aspect ratio and rapid decrease in the roundness and the solidity with gas velocity. A possible mechanism of aggregates formation was proposed based on the variations of aggregates properties with gas velocity. The obtained Heywood diameters of aggregates have been firstly correlated with the experimental parameter.

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Evaluation of the Effect of Particle Size on Erosion Calculations Utilizing CFD and Comparison With Submerged Slurry Jet Experiments

Volume 5: Multiphase Flow ◽

10.1115/ajkfluids2019-5587 ◽

2019 ◽

Author(s):

Soroor Karimi ◽

Jun Zhang ◽

Siamack A. Shirazi ◽

Brenton S. McLaury

Keyword(s):

Experimental Data ◽

Particle Size ◽

Jet Impingement ◽

Computational Procedure ◽

Particle Sizes ◽

Grid Spacing ◽

Concentration Effects ◽

Erosion Models ◽

Effect Of Particle Size ◽

Corrosion Research

Abstract The effects of particle size on erosion magnitude and erosion profiles are investigated experimentally in a submerged slurry jet impingement facility. The slurries were diluted to avoid concentration effects on the flow field and the resulting erosion. The experiments are performed with particle sizes of 25, 75, 150, 300, and 600 μm. Experimental results demonstrate different erosion severity and pattern for the various particle sizes. It is critical to have a reliable and accurate tool to predict erosion for different particle sizes. Previously, a comprehensive CFD-based procedure to predict erosion for various particle sizes was proposed by investigators at the Erosion/Corrosion Research Center (E/CRC). A feature of this procedure is that it can account for particle size in more detail than previous methods. In this study, the computational procedure is applied to conditions of the present experimental data. Particle impact parameters are extracted to explain the effect of particle size on the resulting erosion. The predicted results are compared with data which demonstrate possible shortcomings of the available CFD based techniques for predicting solid particle erosion. The results indicate that with proper use of grid spacing near the wall, the CFD-based erosion calculation method with existing erosion models can predict the trend of the experimental data, though improvements are still needed to the models to accurately account for particle size effects.

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