Floating Metal Particle Motion Characteristics with Shape and Size Variation in the Oil Insulation Under DC Voltage

2019 ◽  
Author(s):  
Daniar Fahmi ◽  
I Made Yulistya Negara ◽  
Dimas Anton Asfani ◽  
I Gusti Ngurah Satriyadi Hernanda ◽  
Tasha Hadianty Deliana ◽  
...  
Keyword(s):  
Particle Motion ◽  
Metal Particle ◽  
Size Variation ◽  
Dc Voltage ◽  
Motion Characteristics ◽  
Shape And Size

Shape and size variation of Jenynsia lineata (Jenyns 1842) (Cyprinodontiformes: Anablepidae) from different coastal environments

Hydrobiologia ◽  
2018 ◽  
Vol 828 (1) ◽  
pp. 21-39 ◽  
Author(s):  
Giselle Xavier Perazzo ◽  
Fabiano Corrêa ◽  
Pablo Calviño ◽  
Felipe Alonso ◽  
Walter Salzburger ◽  
...  
Keyword(s):  
Size Variation ◽  
Coastal Environments ◽  
Shape And Size

scholarly journals Influence of DC Electric Fields on Pollution of HVDC Composite Insulator Short Samples with Different Environmental Parameters

Energies ◽  
2019 ◽  
Vol 12 (12) ◽  
pp. 2304 ◽  
Author(s):  
Xinhan Qiao ◽  
Zhijin Zhang ◽  
Xingliang Jiang ◽  
Tian Liang
Keyword(s):  
Power Systems ◽  
Electric Fields ◽  
Particle Motion ◽  
Particle Diameter ◽  
Environmental Parameters ◽  
Composite Insulator ◽  
High Voltage Direct Current ◽  
Electrical Stress ◽  
Motion Characteristics ◽  
Dc Electric Fields

Pollution-induced flashover is a serious threat to the safe operation of power systems. With the development of High Voltage Direct Current (HVDC), it is necessary to study insulator contamination in DC electric fields. In this paper, the energized wind tunnel contamination test was conducted in order to systematically study the pollution ratio, k (ratio of non-soluble deposit density (NSDD) of a DC-energized condition to a non-energized condition), under different environmental parameters. Later, a two-dimensional contamination model of short samples of an HVDC composite insulator was established. The particle motion characteristics under different environmental parameters were then analyzed by the finite element method (FEM). The research results showed that—the DC electric field had an influence on particle motion but in different environments, the degree of influence was different. In addition, k was found to largely vary, with a variation in the environmental parameters. When the electrical stress (Es) increased from 0 to 70 kV/m, k increased gradually. However, when the wind speed (ws) increased, k experienced a decreasing trend. Finally, as the particle diameter (dp) decreased, k increased at first, followed by a decrease, and then again showed an increase. The results of the pollution ratio, k, for different environmental parameters are of great importance for guiding anti-pollution work in power systems.

Numerical simulation of particle motion characteristics in quantitative seed feeding system

2020 ◽  
Vol 367 ◽  
pp. 643-658
Author(s):  
Xiaojun Gao ◽  
Zongyan Zhou ◽  
Yang Xu ◽  
Yingbo Yu ◽  
Yuan Su ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Particle Motion ◽  
Feeding System ◽  
Motion Characteristics

scholarly journals The genetic control of leaf and petal allometric variations in Arabidopsis thaliana

2020 ◽  
Author(s):  
Xin Li ◽  
Yaohua Zhang ◽  
Suxin Yang ◽  
Chunxia Wu ◽  
Qun Shao ◽  
...  
Keyword(s):  
Arabidopsis Thaliana ◽  
Genetic Basis ◽  
Size Variation ◽  
Principal Component ◽  
Confidence Regions ◽  
Stem Length ◽  
Common Framework ◽  
Organ Shape ◽  
Petal Size ◽  
Shape And Size

Abstract BackgroundOrgan shape and size covariation (allometry) are essential concepts for the study of evolution and development. Although ample research has been conducted on organ shape and size, little research has considered the correlated variation of these two traits and quantitatively measured the variation in a common framework. The genetic basis of allometry variation in a single organ or among different organs is also relatively unknown.ResultsA principal component analysis (PCA) of organ landmarks and outlines was conducted and used to quantitatively capture shape and size variation in leaves and petals of multiparent advanced generation intercross (MAGIC) populations of Arabidopsis thaliana. The PCA indicated that size variation was a major component of allometry variation and revealed negatively correlated changes in leaf and petal size. After quantitative trait loci (QTL) mapping, five QTLs for the fourth leaf, 11 QTLs for the seventh leaf, and 12 QTLs for petal size and shape were identified. These QTLs were not identical to those previously identified, with the exception of the ER locus. The allometry model was also used to measure the leaf and petal allometry covariation to investigate the evolution and genetic coordination between homologous organs. In total, 12 QTLs were identified in association with the fourth leaf and petal allometry covariation, and eight QTLs were identified to be associated with the seventh leaf and petal allometry covariation. In these QTL confidence regions, there were important genes associated with cell proliferation and expansion with alleles unique to the maximal effects accession. In addition, the QTLs associated with life-history traits, such as days to bolting, stem length, and rosette leaf number, which were highly coordinated with climate change and local adaption, were QTL mapped and showed an overlap with leaf and petal allometry, which explained the genetic basis for their correlation.ConclusionsThis study explored the genetic basis for leaf and petal allometry and their interaction, which may provide important information for investigating the correlated variation and evolution of organ shape and size in Arabidopsis.

scholarly journals Coarse Particle Motion Characteristics in a Double-Stage Slurry Pump Considering Leakage Flow

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Hao Jia ◽  
Yuqi Wang ◽  
Zuchao Zhu ◽  
Xianghui Su ◽  
Zhenji Tang
Keyword(s):  
Kinetic Energy ◽  
Particle Motion ◽  
Mining Industry ◽  
Main Flow ◽  
Average Kinetic Energy ◽  
Leakage Flow ◽  
Coarse Particles ◽  
Long Distance ◽  
Pump Design ◽  
Motion Characteristics

Along with the pressing demand for the long-distance transportation of coarse particles in the deep-sea mining industry, evaluating the slurry pump’s passing through and erosive wear by studying the particle motion characteristics and the slurry behavior is becoming increasingly important. Research on the influence of leakage flow through the clearance and balancing devices on the motion characteristic of granular grain flow is of great significance but has been seldom studied. This study coupled the discrete element method with the CFD method to investigate the comprehensive effect of a double-stage slurry pump’s main flow and leakage flow on the motion characteristics of particles with a 10 mm diameter. Results show that the leakage flow occupation in main flow falls from 26%–27% to 8%–9% for the two stages, with the flow rate increasing from 80 m3/h to 200 m3/h. In the first stage with leakage, accumulation of coarse particles was observed at the impeller eye, which should be paid much attention to slurry pumps’ operation to eliminate the chance of blockage. In the nonleak situation, although the increment of the average kinetic energy of particles through the impeller is more significant than in the leak case, most of them dissipate primarily by more than 10% collision in the bowl diffuser. In the leak or nonleak case, the average kinetic energy of particles was more than twice through the first stage but only 1.1 times through the second stage. The selection of stages in the slurry pump design should consider the limitation of particle velocity improvement.

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