scholarly journals A Study on the Dynamic Transmission Law of Spiral Drum Cutting Coal Rock Based on ANSYS/LS-DYNA Simulation

Complexity ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-14 ◽  
Author(s):  
Lijuan Zhao ◽  
Hongmei Liu ◽  
Wenchao Zhou
Keyword(s):  
Stress Distribution ◽  
Maximum Stress ◽  
Coupled Model ◽  
Time History ◽  
Coupling Model ◽  
Working Process ◽  
Obvious Effect ◽  
Design And Optimization ◽  
Plastic Domain ◽  
Coal Rock

The ANSYS/LS-DYNA software has been used in this paper to establish the coal rock coupling model. A dynamic simulation of the cutting process was used to analyze the variation of the load. Based on the dynamic analysis of the coal and rock that were cut by the spiral drum, the stress cloud diagram of the coupled model of the spiral drum and the coal and the plastic domain evolution law of the coal and the rock were obtained from the coal to the rock. The time history curves of the parameters, such as the stress and strain of the drum and the pick, were obtained, and the stress distribution of the spiral drum during the working process was ascertained. The results showed that when the spiral drum cuts the interface between the coal and the rock, the coal and the rock collapsed and the working load fluctuated. Changing the traction speed in order to change the rotational speed of the drum had a more obvious effect on the load and the stress on the drum. Through the use of simulation, the stress distribution cloud diagram of the drum was obtained. The study has shown that the stress on the end plate was significantly higher than that on the cutting blade. The maximum stress acting on the alloy head was 1209.26 MPa. This study has provided a basis for the design and optimization of the drum with regard to reliability.

Research of the Connecting Form about the Spherical Shell and the Nozzle

2011 ◽  
Vol 413 ◽  
pp. 520-523
Author(s):  
Cai Xia Luo
Keyword(s):  
Finite Element ◽  
Stress Distribution ◽  
Finite Element Model ◽  
Spherical Shell ◽  
Maximum Stress ◽  
Peak Stress ◽  
Element Model ◽  
Small Opening ◽  
Large Opening ◽  
Reducing Stress

The Stress Distribution in the Connection of the Spherical Shell and the Opening Nozzle Is Very Complex. Sharp-Angled Transition and Round Transition Are Used Respectively in the Connection in the Light of the Spherical Shell with the Small Opening and the Large One. the Influence of the Two Connecting Forms on Stress Distribution Is Analyzed by Establishing Finite Element Model and Solving it. the Result Shows there Is Obvious Stress Concentration in the Connection. Round Transition Can Reduce the Maximum Stress in Comparison with Sharp-Angled Transition in both Cases of the Small Opening and the Large Opening, Mainly Reducing the Bending Stress and the Peak Stress, but Not the Membrane Stress. the Effect of Round Transition on Reducing Stress Was Not Significant. so Sharp-Angled Transition Should Be Adopted in the Connection when a Finite Element Model Is Built for Simplification in the Future.

scholarly journals Study on Impact Damage and Energy Dissipation of Coal Rock Exposed to High Temperatures

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Tu-bing Yin ◽  
Kang Peng ◽  
Liang Wang ◽  
Pin Wang ◽  
Xu-yan Yin ◽  
...  
Keyword(s):  
High Temperatures ◽  
Failure Modes ◽  
Split Hopkinson Pressure Bar ◽  
Impact Damage ◽  
Time History ◽  
Hopkinson Pressure Bar ◽  
Absorbed Energy ◽  
Failure Patterns ◽  
Temperature Conditions ◽  
Coal Rock

The dynamic failure characteristics of coal rock exposed to high temperatures were studied by using a split Hopkinson pressure bar (SHPB) system. The relationship between energy and time history under different temperature conditions was obtained. The energy evolution and the failure modes of specimens were analyzed. Results are as follows: during the test, more than 60% of the incident energy was not involved in the breaking of the sample, while it was reflected back. With the increase of temperature, the reflected energy increased continuously; transmitted and absorbed energy showed an opposite variation. At the temperature of 25 to 100°C, the absorbed energy was less than that transmitted, while this phenomenon was opposite after 100°C. The values of specific energy absorption (SEA) were distributed at 0.04 to 0.1 J·cm−3, and its evolution with temperature could be divided into four different stages. Under different temperature conditions, the failure modes and the broken blocks of the samples were obviously different, combining with the variation of microstructure characteristics of coal at high temperatures; the physical mechanism of damage and failure patterns of coal rock are explained from the viewpoint of energy.

Stress Distribution Analysis of Different Types of Blade for a Fermentation System

2013 ◽  
Vol 479-480 ◽  
pp. 319-323
Author(s):  
Cheng Chi Wang ◽  
Po Jen Cheng ◽  
Kuo Chi Liu
Keyword(s):  
Stress Distribution ◽  
Maximum Stress ◽  
Effective Means ◽  
Materials Processing ◽  
Distribution Analysis ◽  
Stress Distributions ◽  
Fermentation System ◽  
Different Types ◽  
Inclined Angle ◽  
Key Parameter

Fermentation system is widely used for food manufacturing, materials processing and chemical reaction etc. Different types of blade in the tank for fermentation cause distinct stress distributions on the surface between fluid and blade, and appear various flow fields in the tank. So, this paper is mainly focused on analyzing the stress field of blades under different scales of blade with fixing rotational speed. The results show that the ratio of blade length to width influences stress distribution on the blades. At the same time, the inclined angle of blade is also the key parameter for the consideration of design and appropriate design will decrease the maximum stress. The results provide an effective means of gaining insights into the stress distribution of fermentation system.

Strength Analysis of Parallel Grooved Drum

2013 ◽  
Vol 387 ◽  
pp. 115-119
Author(s):  
Qing Zhang ◽  
Kun Zhao ◽  
Ying Yue Xiao ◽  
Xian Rong Qin ◽  
Yuan Tao Sun ◽  
...  
Keyword(s):  
Stress Distribution ◽  
Wall Thickness ◽  
Structure Design ◽  
Strength Analysis ◽  
Design And Optimization ◽  
Simulation Results

Only the basic wall thickness of drum is taken under consideration in traditional parallel grooved drum strength analysis, which is quite conservative for ignoring the thickness of the groove. So in this paper, it is aimed at comparing the strength simulation results for two drum models with and without the thickness of the groove and analyzing the stress distribution of the drum structure, which provides reference for the structure design and optimization of the drum.

Analysis of Transient Thermal Stress of IGBT Module Based on Electrical-Thermal-Mechanical Coupling Model

2014 ◽  
Vol 986-987 ◽  
pp. 823-827
Author(s):  
Qing Yuan Zheng ◽  
Min You Chen ◽  
Bing Gao ◽  
Nan Jiang
Keyword(s):  
Thermal Stress ◽  
Stress Distribution ◽  
Uniform Distribution ◽  
Inelastic Strain ◽  
Coupling Model ◽  
Power Module ◽  
Mechanical Coupling ◽  
Fem Method ◽  
Igbt Module ◽  
Solder Layer

Reliability of IGBT power module is one of the biggest concerns regarding wind power system, which generates the non-uniform distribution of temperature and thermal stress. The effects of non-uniform distribution will cause failure of IGBT module. Therefore, analysis of thermal mechanical stress distribution is crucially important for investigation of IGBT failure mechanism. This paper uses FEM method to establish an electrical-thermal mechanical coupling model of IGBT power module. Firstly, thermal stress distribution of solder layer is studied under power cycling. Then, the effects of initial failure of solder layer on the characteristic of IGBT module is investigated. Experimental results indicate that the strain energy density and inelastic strain are higher which will reduce reliability and lifetime of power modules.

Stress Calculation of a Spherical Tank on Settled Ground Based on FEM

2013 ◽  
Vol 331 ◽  
pp. 110-113
Author(s):  
Hong Li Gao ◽  
Wei Jun Li ◽  
Zhi Hai Li
Keyword(s):  
Stress Distribution ◽  
Maximum Stress ◽  
Differential Settlement ◽  
Foundation Settlement ◽  
Stress Calculation ◽  
Spherical Tank

In this paper, a model of a LGP spherical tank supported by 8 equator tangent-type supporting on settled ground was built.The stress on the shell,on the pillars and on the connection of pillars with shell were calculated,the stress distribution on shell,pillars and the connection of pillars with shell were obtained, the influence of foundation settlement to the stress of shell and pillars were studied. The results showed that the differential settlement produced a less affect on the shell,but a greater impact on the pillars. The maximum stress arose at the connection between pillars and shell ,there is a big stress area in the connectors area.

scholarly journals Rigid-flexible coupled dynamics analysis of 3-revolute-prismatic-spherical parallel robot based on multi-software platform

2019 ◽  
Vol 11 (3) ◽  
pp. 168781401982645 ◽  
Author(s):  
Haitao Luo ◽  
Jia Fu ◽  
Lichuang Jiao ◽  
Ning Chen ◽  
Tingke Wu
Keyword(s):  
Computer Technology ◽  
Maximum Stress ◽  
Maximum Error ◽  
Parallel Robot ◽  
Mechanical Analysis ◽  
Response Analysis ◽  
Analysis Method ◽  
Software Platform ◽  
Design And Optimization ◽  
Multi Body

Kinematics and dynamics are the most important and basic tool for robot research. With the help of computer technology and the respective advantages of three kinds of software, a new method of co-simulation of parallel robot based on multi-platform is proposed, and the mechanical model of multi-body system of 3-revolute-prismatic-spherical parallel robot is established. According to the mechanical analysis of the parallel robot, the rigid-flexible coupling analysis method is adopted. The displacement error shows a periodic change with a period of 4.2 s and the maximum error is [Formula: see text]. The dangerous part of the structure is the root of the lower link, and its maximum stress is 202.64 MPa less than the yield strength of the material. The multi-software platform co-simulation improves the accuracy of the dynamic response analysis of the part under dynamic load, and provides an important theoretical basis for the design and optimization of the parallel robot.

Experimental investigation on the characteristics of the dynamic rail pad force and its stress distribution in the time and frequency domain

2019 ◽  
Vol 234 (2) ◽  
pp. 201-213 ◽  
Author(s):  
Xu Zhang ◽  
Chunfa Zhao ◽  
Xiaobo Ren ◽  
Yang Feng ◽  
Can Shi ◽  
...  
Keyword(s):  
Stress Distribution ◽  
Frequency Domain ◽  
Maximum Stress ◽  
Field Tests ◽  
Service Condition ◽  
Field Testing ◽  
Dominant Frequency ◽  
Test Results ◽  
Parabolic Shape ◽  
Dominant Frequencies

The rail pad force and its stress distribution have critical influences on the performance and fatigue life of the rail, fasteners, and sleepers. The characteristics of the rail pad force and its stress distribution in the time and frequency domain obtained from field tests carried out using matrix-based tactile surface sensor are presented in this paper. The field testing involved rail pads under various axle-loads of running trains at different speeds. The influences that the train axle-load, the operational speed, and the rail pad stiffness have on the rail pad force and its stress distribution are analyzed. The test results indicate that the rail pad stiffness has a remarkable influence on the amplitude of the rail pad force but has little influence on its dominant frequencies. The first dominant frequency of the rail pad force is quite close to the passing frequency of the vehicle length. The stress distribution on the rail pad has a parabolic shape along the longitudinal and the lateral directions with the large stress appearing near the center of the rail pad, and is remarkably affected by the service condition of the rail pad. The maximum stress is about 2.5 to 3 times of the average stress, which is significantly greater than the nominal stress resulting from the assumption of uniform stress distribution.

Modeling the Effect of Groundwater Abstraction on Wei River Riverine Ecological Flow Using the Coupled Model of Groundwater and Surfacewater

2012 ◽  
Vol 433-440 ◽  
pp. 1453-1457 ◽  
Author(s):  
Bo Zhang ◽  
Mei Hong ◽  
Zu Hao Zhou ◽  
Yang Wen Jia ◽  
Hui Li ◽  
...  
Keyword(s):  
Overland Flow ◽  
River Flow ◽  
Shallow Groundwater ◽  
Coupled Model ◽  
Wave Model ◽  
Coupling Model ◽  
Analysis Tool ◽  
Groundwater Abstraction ◽  
Coupled Calculation ◽  
Balance Analysis

In this study, the latest version of river boundary modular in MODFLOW, was employed in this watershed for the case study of coupled calculation between river and aquifer. Because of the complex interaction of groundwater and surface water in this area, the coupling model of SFR modular for river diffusive wave model and isochronal cell method for overland flow confluence model and numerical calculation of groundwater is coupled to simulate the runoff process of Weihe river. The model validation was aiming at river flow rate and groundwater field. The results show that 65% of the abstracted shallow groundwater comes from the river water and the reduced amount of river baseflow by the groundwater abstraction is 122 million m3 per year, which is also validated by a water balance analysis of river links. The 50% reduction of shallow groundwater abstraction may lead to a recover of 3 m of the lowest groundwater level. The study provides a sound analysis tool to the integrated water resources and ecology management in the region.

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