Correlating Particle Size Distribution in a Crushed Zone to Perforating Permeability Damage and Modeling Using Fragmentation Fractal Theory

2002 ◽  
Author(s):  
C. Ozgen Karacan ◽  
Phillip M. Halleck
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Fractal Theory ◽  
Crushed Zone ◽  
Permeability Damage

scholarly journals Green Preparation, Spheroidal, and Superior Property of Nano-1,3,5,7-Tetranittro-1,3,5,7-Tetrazocane

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Xinlei Jia ◽  
Jingyu Wang ◽  
Conghua Hou ◽  
Yingxin Tan
Keyword(s):  
Activation Energy ◽  
Particle Size ◽  
Fractal Dimension ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Fractal Theory ◽  
Crystal Form ◽  
Decomposition Temperature ◽  
Scanning Calorimetry ◽  
The Impact

Herein, a green process for preparing nano-HMX, mechanical demulsification shearing (MDS) technology, was developed. Nano-HMX was successfully fabricated via MDS technology without using any chemical reagents, and the fabrication mechanism was proposed. Based on the “fractal theory,” the optimal shearing time for mechanical emulsification was deduced by calculating the fractal dimension of the particle size distribution. The as-prepared nano-HMX was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and differential scanning calorimetry (DSC). And the impact sensitivities of HMX particles were contrastively investigated. The raw HMX had a lower fractal dimension of 1.9273. The ideal shearing time was 7 h. The resultant nano-HMX possessed a particle size distribution ranging from 203.3 nm to 509.1 nm as compared to raw HMX. Nano-HMX particles were dense spherical, maintaining β-HMX crystal form. In addition, they had much lower impact sensitivity. However, the apparent activation energy as well as thermal decomposition temperature of nano-HMX particles was decreased, attributing to the reduced probability for hotspot generation. Especially when the shearing time was 7 h, the activation energy was markedly decreased.

scholarly journals Evaluation of particle size distribution of granular blasting materials based on the fractal theory

2019 ◽  
Vol 11 (10) ◽  
pp. 168781401988156 ◽  
Author(s):  
Jiejie Ji ◽  
Qiang Yao ◽  
Faming Wu ◽  
Hongtao Li
Keyword(s):  
Particle Size ◽  
Fractal Dimension ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Evaluation Method ◽  
Fractal Theory ◽  
Distribution Model ◽  
Uniformity Coefficient ◽  
Functional Relationships ◽  
Fine Grain

The particle size distribution of granular blasting materials has a vital influence on the filling quality of earth-rockfill dams. The engineering experience-based method used to evaluate the particle size distribution has shortcomings at both the theoretical and practical aspects. This article proposes a new evaluation method based on the fractal theory. Grading sieve tests on granular materials, mass fractal analysis of particle size distribution, and a probability distribution model test of the characteristic parameters are used to revise the functional relationships between the fractal dimension D and the uniformity coefficient/curvature coefficient ( Cu/ Cc) of the grading curve. The feasibility of using D to evaluate the particle size distribution and the optimal fine grain content is then analyzed and determined. According to the results, the geometric shapes of the granular blasting materials have fractal characteristics, and their particle size distribution has a fractal distribution. The ranges of D where the rockfill and transition materials have a good particle size distribution are D = 2.254–2.529 and D = 2.358–2.559, corresponding to optimal fine grain content of 1.953%–11.805% and 10.268%–23.123%, respectively. Fractal dimension has a solid theoretical basis and strong practical applicability as an evaluation index for the particle size distribution of granular blasting materials.

scholarly journals Analysis of the Correlation Between Strength and Fractal Dimension of Gravelly Soil in Debris-flow Source Areas

2016 ◽  
Vol 10 (1) ◽  
pp. 866-876 ◽  
Author(s):  
He Na ◽  
Li Tao ◽  
Zhong Wei ◽  
Tom Cosgrove ◽  
Zeng Mei
Keyword(s):  
Particle Size ◽  
Fractal Dimension ◽  
Internal Friction ◽  
Particle Size Distribution ◽  
Debris Flow ◽  
Size Distribution ◽  
Fractal Theory ◽  
Soil Samples ◽  
Gravelly Soil ◽  
Cohesion Force

Particle size distribution of gravelly soil plays a crucial role in debris flow initiation. For better understanding the mechanism of debris flow formation, two crucial mechanical property parameters of the gravelly soil are required to be studied meticulously: hydraulic conductivity and strength. With the aim of measuring the composition of the gravelly soil, 182 soil samples were taken from debris flow prone areas. With the aid of a sieve test, the particle size distribution of the samples can be obtained and analyzed. Then fractal theory was employed to compute the fractal dimension of the soil samples. By analyzing the results of sieve test (particle size distribution curves) and the results of the fractal theory calculations, the relationship between fractal dimension and particle size distribution can be explored. The results illustrate that the particle compositions of the gravelly soil tends to remain uniform as the fractal dimension increases. Moreover, as the coarse particle content increases, the fractal dimension decreases. To better understand the formation mechanism of debris flows, direct shear tests were conducted. Subsequently the experimental results were analyzed. By analysis, the following conclusions can be drawn: the soil strength decreases as the fractal dimension increases, and for soils with lower moisture content and identical dry density, a linear relationship between fractal dimension and cohesion force was identified. Moreover, cohesion force and internal friction force both decrease as the fractal dimension increases, but the internal friction angle decreases slightly while the cohesion force decreases greatly. Therefore we concluded that soil strength decreased mainly due to the reduction in cohesion force.

scholarly journals Numerical Simulation of Rockfill Materials Based on Fractal Theory

2021 ◽  
Vol 12 (1) ◽  
pp. 289
Author(s):  
Hongxing Han ◽  
Yun Ma ◽  
Wei He ◽  
Weifang Yang ◽  
Xudong Fu
Keyword(s):  
Particle Size ◽  
Fractal Dimension ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Fine Particles ◽  
Mechanical Performance ◽  
Fractal Theory ◽  
Two Dimensions ◽  
Performance Indexes ◽  
Fractal Characteristics

With the use of the particle flow code in two dimensions, a fractal model is established with the number of particles of different particle fractions used as the statistics to study the fractal characteristics of particle size distribution. Numerically simulated specimens obtained by four scale methods are subjected to the relative density test and the biaxial compression test to explore the influences of fractal dimension D on the macroscopic and mesomechanical properties of specimens, as well as to study the relationship between fractal dimension D and different mechanical performance indexes. Results show that the particle size distribution of each of the four groups after scale exhibits fractal characteristics, with the fractal dimension D ranging from 1.27 to 2.03. The number of fine particles in the specimen increases with the fractal dimension D, the particle aggregates become more compact, the macroscopic mechanical properties of the specimens are improved, and a linear relationship exists between the fractal dimension D and different mechanical performance indexes. A large fractal dimension D corresponds to a great mesoparticle coordination number.

The Density Functions of Pore-Size and Particle-Size Distribution Established by Using Fractal Theory and their Applications

2012 ◽  
Vol 170-173 ◽  
pp. 148-152 ◽  
Author(s):  
Gao Liang Tao ◽  
Qi Zhi Hu ◽  
Ming Yang Pan ◽  
Xuan Hu
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Pore Size ◽  
Soil Sample ◽  
Size Distribution ◽  
Fractal Theory ◽  
Soil Porosity ◽  
Density Functions ◽  
Menger Sponge ◽  
Sierpiński Carpet

Based on the Sierpinski carpet and Menger sponge models, the density functions of pore-size and particle-size distribution are put forward. Using the proposed density functions, expressions of soil porosity and grain mass are obtained. Using the expression of soil porosity, the porosity of soil sample is correctly predicted. The expression of grain mass is used to predict the mass of grains. The results show that the mass predictions of grains of size smaller than 0.002mm are very close to the measure results.

Effects of Particle Size Distribution on Corrosion Rate of Carbon Steel in Soil

2020 ◽  
Vol 69 (4) ◽  
pp. 102-106
Author(s):  
Shota Ohki ◽  
Shingo Mineta ◽  
Mamoru Mizunuma ◽  
Soichi Oka ◽  
Masayuki Tsuda
Keyword(s):  
Particle Size ◽  
Carbon Steel ◽  
Corrosion Rate ◽  
Particle Size Distribution ◽  
Size Distribution
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