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Full-Text Articles in Physical Sciences and Mathematics
Numerical Simulation On Mechanism Of Thrust Fault Reactivation During Mining, Min Feihu, Xiang Biwei, Liu Hui, Zhu Xiaojun
Numerical Simulation On Mechanism Of Thrust Fault Reactivation During Mining, Min Feihu, Xiang Biwei, Liu Hui, Zhu Xiaojun
Coal Geology & Exploration
It is a hot issue in mine disaster research about the activation of faults during the process of coal mining and excavation. In order to reveal the influence of coal mining on fault activation under different fault dip conditions, Xinji No.2 mine in Huainan coalfield was taken as an example, and numerical simulation with FLAC3D was used to systematically study the dynamic activation law of thrust faults during mining beside the faults, and to clarify the relationship among fault activation position and fault dip angle and excavated distance of working face. The results show that the fault activation is …
Reasonable Length Of Working Face 11-101 During Mining Above Confined Aquifer In Tuanbai Mine, Li Gang, Zhang Kai, Su Junhui, Wang Jinbo
Reasonable Length Of Working Face 11-101 During Mining Above Confined Aquifer In Tuanbai Mine, Li Gang, Zhang Kai, Su Junhui, Wang Jinbo
Coal Geology & Exploration
The working face 11-101 of Tuanbai coal mine in Huozhou, Shanxi Province is exploited above aquifer. In order to prevent floor water inrush accidents during mining, research combination of elasto-plastic theory, on-site measurement and numerical simulation was carried out to analyze the development rule of failure depth of the floor, then the reasonable length of the mining face under this condition was determined. The result shows that with the advancement of working face, the bottom plate of lagging working face is stretched and destroyed at about 6 m behind the lagging working face, and the bottom plate has a wedge …
Numerical Analysis Of Temperature Field Of Underwater Dredging Artificial Frozen Plate, Wu Yuwei, Hu Jun, Wang Zhixin, Zeng Dongling, Wang Shucheng
Numerical Analysis Of Temperature Field Of Underwater Dredging Artificial Frozen Plate, Wu Yuwei, Hu Jun, Wang Zhixin, Zeng Dongling, Wang Shucheng
Coal Geology & Exploration
In order to understand the development of the temperature field of artificial freeze dredging plates and the process of the formation of frozen curtains, the finite element analysis was used to perform numerical analysis using the single factor analysis method for research of the frozen process in different circumstances of geometric size of plate and physical environment of the soil under water. The results show that the correlation between the different geometric dimensions of the frozen plate and the dredging depth is weak, and the geometric dimension of the frozen plate can only change the area of dredging; for the …
Finite Element Numerical Simulation Of Pre-Damaged Reinforced Concrete Beam, Jiaquan Wu, Hongyan Li, Ye Fei, Xinyu Zhang, Kun Ma
Finite Element Numerical Simulation Of Pre-Damaged Reinforced Concrete Beam, Jiaquan Wu, Hongyan Li, Ye Fei, Xinyu Zhang, Kun Ma
Journal of System Simulation
Abstract: Based on the theory of model analysis, the general variation of model parameters, such as the structure natural frequency, displacement mode, curvature mode and strain mode etc.model of reinforced concrete beams with different damage locations and different damage states are reversely studied by finite element numerical simulation with the pre-damaged reinforced concrete beam structure as the research object, model and the aptability, sensitivity in the reinforced concrete structure damage identification are discussed. The results show that the frequency and displacement mode can not effectively reflect the existence of structural damage, but curvature mode and strain mode can reflect the …
Mechanism Of Biofouling Control On Micro-Structured Surface, Chunxi Li, Quanxi Xue, Zhang Shuo, Xuemin Ye
Mechanism Of Biofouling Control On Micro-Structured Surface, Chunxi Li, Quanxi Xue, Zhang Shuo, Xuemin Ye
Journal of System Simulation
Abstract: Changing the wall microstructure geometry can improve the performance of surface antifouling and selfcleaning. A 3D numerical simulation of microfluidic in the near-wall region attached with microorganisms is performed with Fluent, and the kinetic and dynamic characteristics of fluid in the near- wall region are examined. The inherent mechanism of antifouling on microwell surfaces is discussed. Results reveal that streamwise vortices are formed in the microwells, thus the distinctly periodic fluctuations of velocity, strain rate and wall shear stress on microwell surfaces are exhibited, resulting in the interference on microorganisms migration and the harder adhesion of microorganisms to …
Research On Impact Performance Of Layer-Number Of 2024 Aerospace Aluminum Alloy Immobilized Target Against Bird Strike, Jianxin Xu, Jiajun Yuan, Yunfei Deng
Research On Impact Performance Of Layer-Number Of 2024 Aerospace Aluminum Alloy Immobilized Target Against Bird Strike, Jianxin Xu, Jiajun Yuan, Yunfei Deng
Journal of System Simulation
Abstract: In order to investigate the anti-penetration performance of target plate of the same thickness under different number of layers, a model of SPH(Smoothed Particle Hydrodynamics) cylindrical bird bullet to impact 2024 aerospace aluminum alloy Lagrange target is established by using the AUTODYN finite element software. The thickness of target is 1 mm, 2 mm, 3 mm and 4 mm, 1 mm and 2 mm target plate is divided into single and double, 3 mm target plate is divided into single, double and three layers, 4 mm target plate is divided into single, double and four layers. …
Simulation Research Of Closed Control System For Equipment Operation And Maintenance With Parts Inventory System, Li Bing, Wang Xing, Xuan Hua, Xueyuan Wang
Simulation Research Of Closed Control System For Equipment Operation And Maintenance With Parts Inventory System, Li Bing, Wang Xing, Xuan Hua, Xueyuan Wang
Journal of System Simulation
Abstract: The highly reliable equipment operation and maintenance system is very important to enterprise’s safety production. The control system for equipment operation and maintenance with a parts inventory system is generally discussed. The proposed system is composed of a parts inventory subsystem, an equipment operation subsystem and an equipment maintenance subsystem as parallel and series form. And the control system belongs to a multi-level closed loop system. The system is a kind of discrete event dynamic system. So it is difficult to be described with traditional mathematical analysis methods. The multi-class closed control system simulation model is established with Simulink …
Penetrating Capability Of Different Annular Shaped Charge Warhead, Tan Bo, Hongjie Liu, Run Miao, Zeng Liang
Penetrating Capability Of Different Annular Shaped Charge Warhead, Tan Bo, Hongjie Liu, Run Miao, Zeng Liang
Journal of System Simulation
Abstract: On the basis of the existing missile warhead, an annular shaped charge is added in the front of warhead without changing the size and increasing the weight of the warhead. ANSYS/LS-DYNA is used to simulate the whole process of the formation of annular jet and penetration of a double target and analyze the movement characteristics of two kinds of different annular jet in the air. The target damage effect is acquired. The calculation results show that the difference of the penetration ability on the double layer target of jet between center -ball shaped charge and that of the hollow …
Research Of Turbulence Model Parameters Correction For Oil Flow Of Pipeline, Jisen Wang, Jia Qian, Chen Chen, Yaping Zhang, Du Jiang
Research Of Turbulence Model Parameters Correction For Oil Flow Of Pipeline, Jisen Wang, Jia Qian, Chen Chen, Yaping Zhang, Du Jiang
Journal of System Simulation
Abstract: Because of the limitation of the parameters in the Realizable k-ε two equations model, the model is no longer suitable to simulate the pressure loss of the turbulent oil flow of pipelines. A mathematical model of the oil flow of pipeline is built, and the Realizable k-ε model default parameters are modified according to the test results of YH-15 aviation hydraulic oil to obtain new parameters used to simulate the pressure loss in other conditions. Compared to the model with default parameters, numerical simulations and experimental results show that the maximum relative error is reduced …
Cfd Based Analysis And Improvement Of The Flow Field Of Stirred Tank Reactor For Crystallization, Zewen Ma, Liu Tao, Xudong Sun
Cfd Based Analysis And Improvement Of The Flow Field Of Stirred Tank Reactor For Crystallization, Zewen Ma, Liu Tao, Xudong Sun
Journal of System Simulation
Abstract: The computational fluid dynamics (CFD) method is adopted to analyze the flow field of 1L stirred tank reactor for crystallization. A popular CFD software named FLUENT is used to analyze the influence of a single layer turbine agitator on the flow field in a stirred tank reactor. The standard turbulence model of k-ε is employed to simulate a three-dimensional single-phase flow field of water solution. Simulation studies indicate that the simulated flow field is consistent with real distribution of the flow field, while it is seen that uniform blending can be achieved in the lower and middle parts of …
Numerical Simulation Of Thermal Comfort And Pm10 Concentration Distribution In A320 Aircraft Cabin, Jiaquan Lin, Ruiting Wang
Numerical Simulation Of Thermal Comfort And Pm10 Concentration Distribution In A320 Aircraft Cabin, Jiaquan Lin, Ruiting Wang
Journal of System Simulation
Abstract: A model of A320 aircraft cabin and human body was established using CFD. Temperature field, velocity field and PM10 concentration field was simulated at different air supply rate of the bridge load air conditioning based on mathematical model of fluid dynamics in cabin. The values of the ADPI and drainage efficiency were calculated respectively at different air supply rate. The optimal supply air velocity evaluation function was constructed based on ADPI and drainage efficiency. The wind speed, temperature and PM10 concentration of the sample points were used to calculate the value of the evaluation function with different …
Simulation Of Migration Of Hexavalent Chromium In Groundwater, Liu Ling, Liping Xiao, Xilin Li
Simulation Of Migration Of Hexavalent Chromium In Groundwater, Liu Ling, Liping Xiao, Xilin Li
Journal of System Simulation
Abstract: Taking chromite ore processing residue site in Shenyang city of Liaoning province as a research object, the static adsorption experiment and the dynamic soil column experiment were carried out, and the adsorption characteristics and the migration law for hexavalent chromium of chromite ore processing residue leachate were analyzed in the groundwater system. A coupled dynamic mathematical model was developed for simulating hexavalent chromium migration in the groundwater system. Numerical simulation of hexavalent chromium migration in groundwater for 40 years before the anti-seepage measure and for 60 years after the anti-seepage measure was completed by using Visual Modflow software. The …
Performance Analysis And Research Of Shark Fin Structure Based On Simulation, Liu Shuang, Lü Chao, Rao Yong, Shiming Wang
Performance Analysis And Research Of Shark Fin Structure Based On Simulation, Liu Shuang, Lü Chao, Rao Yong, Shiming Wang
Journal of System Simulation
Abstract: The shark fin, the pectoral fin and the dorsal fin were studied based on the numerical simulation method; the pressure field, velocity field and flow field of the specimen structure were analyzed with three different flow velocities; the analysis and comparison of the mechanical properties of caudal fin, dorsal fin and pectoral fin were presented. The results show that the setting width of the tail fin can be set to 0.5 ~ 4.8 meters so as to improve the anti-karman vortex effect; the width of the tail fins should be relatively narrow in order to guarantee the base of …
Effect Of Interfacial Curvature On Drag Reduction Of Superhydrophobic Microchannels, Chunxi Li, Zhang Shuo, Xuemin Ye
Effect Of Interfacial Curvature On Drag Reduction Of Superhydrophobic Microchannels, Chunxi Li, Zhang Shuo, Xuemin Ye
Journal of System Simulation
Abstract: The two-dimensional fluid flow in superhydrophobic microchannels with transverse grooves was numerically simulated with Fluent to investigate the impact of the liquid-gas interface curvature on the effective slip behavior in the laminar regime. The effects of shear-free fraction, normalized periodic cell length and Reynolds number on the normalized slip length and pressure drop reduction are also examined. The results show that as protrusion angle increases, the normalized slip length and pressure drop reduction exhibit with single-hump variations. When θ=θopt, increments in the normalized slip length and pressure drop reduction tend to be greater as shear-free …
Analysis And Optimization Of Mobile Phone Antenna Radiation Performance In The Presence Of Head And Hand Phantoms, Erdem Ofli, Chung-Huan Li, Nicolas Chavannes, Niels Kuster
Analysis And Optimization Of Mobile Phone Antenna Radiation Performance In The Presence Of Head And Hand Phantoms, Erdem Ofli, Chung-Huan Li, Nicolas Chavannes, Niels Kuster
Turkish Journal of Electrical Engineering and Computer Sciences
A commercial clam shell phone CAD model is used to numerically investigate the effect of a hand phantom on mobile phone antenna radiation performance. The simulation results show that the grip of the hand phantom is the most important parameter to antenna performance. The antenna is converted into a parameterized form, then optimized to achieve the targeted multi-band performance in real-usage conditions.
Design, Simulation And Tests Of A Low-Cost Microstrip Patch Antenna Arrays For The Wireless Communication, Gonca Çakir, Levent Sevgi̇
Design, Simulation And Tests Of A Low-Cost Microstrip Patch Antenna Arrays For The Wireless Communication, Gonca Çakir, Levent Sevgi̇
Turkish Journal of Electrical Engineering and Computer Sciences
Typical low-cost, low-weight microstrip base station antenna arrays with beam-scanning capabilities are taken into account. In downtowns of large cities like New York, Chicago, and in historical cities like Istanbul, where high buildings are separated by narrow but densely occupied streets, antenna arrays with approximately 20°-35° beam-widths are required to complete the cellular communication coverage. To meet this requirement, new antenna arrays are designed with 35° beam-widths and 60° electronic scanning capabilities. Their characteristics are investigated both numerically and experimentally. An FDTD-based antenna simulation package (M-PATCH) is prepared, tested on canonical structures and against the literature first, for verification and …
Electromagnetic Engineering In The 21^{St} Century: Challenges And Perspectives, Leopold B. Felsen, Levent Sevgi̇
Electromagnetic Engineering In The 21^{St} Century: Challenges And Perspectives, Leopold B. Felsen, Levent Sevgi̇
Turkish Journal of Electrical Engineering and Computer Sciences
This paper aims at a broad-brush look at certain technological and educational challenges that confront wave-oriented electromagnetic (EM) engineering in the 21^{st} century, in a complex computer and technology-driven world with rapidly shifting societal and technical priorities. Simulation strategies for complex EM systems, both analytic and numerical, are reviewed and categorized, and are illustrated on selected practical complex multicomponent system scenarios currently under investigation in Turkey. Educational issues to ensure proper multidisciplinary exposure of new generations of computer-weaned students, who will have to deal with these problems, are touched upon as well.