Effect of Abutment Load of Arch Dam on Stability of Underground Caverns Complex

2014 ◽  
Vol 501-504 ◽  
pp. 2045-2048
Author(s):  
Cun Hui Zhang ◽  
Shu Da Zhou ◽  
Xiu Li Ding ◽  
Shu Ling Huang ◽  
Yu Ting Zhang
Keyword(s):  
Three Dimensional ◽  
Simulation Models ◽  
Arch Dam ◽  
Hydropower Plant ◽  
Underground Powerhouse ◽  
Reservoir Storage ◽  
Underground Caverns ◽  
Operation Period ◽  
Calculation Results ◽  
Key Issues

Considering topographic and geologic conditions, project layout and investments, concret arch dam is adopted in a hydropower plant and underground powerhouses are arranged in mountains on left and right banks. However, the minimum distance between the excavation boundary of abutment of arch dam on elevation 850m and underground powerhouse is only 110m. Abutment load created by reservoir storage, permeability and earthquake may affect general stability of underground caverns in operation period. Thus, using elasto-plastic finite difference method, three dimensional numerical simulation models of underground caverns and slope of abutment of arch dam is establised and proposed key issues are systemly studied. The calculation results show that, under reservoir storage and dam vibration subject to earthquke, abutment load has small effect on plastic zone, displacement and stress around opennings and the caverns would be stable in operation period.

Stability Analysis of Surrounding Rock Mass of Underground Powerhouse Cavern

2013 ◽  
Vol 838-841 ◽  
pp. 878-882
Author(s):  
Xiao Gang He ◽  
Feng Dai ◽  
Nu Wen Xu ◽  
Chun Sha
Keyword(s):  
Surrounding Rock ◽  
Seismic Events ◽  
Distribution Characteristic ◽  
Lagrangian Analysis ◽  
Underground Powerhouse ◽  
Underground Caverns ◽  
Calculation Results ◽  
Microseismic Events ◽  
Plastic Zones ◽  
Distribution Of Stress

The underground powerhouse of Houziyan hydropower station has some typical characteristics such as high strata stress, large span and high sidewalls. In this paper, numerical simulation of continuous excavation and support of the underground caverns was performed using the Fast Lagrangian Analysis of Continuum method (FLAC3D). Then, the distribution characteristic of the deformation field, stress field and plastic zones was analyzed based on the numerical calculation results. In addition, the distribution of stress was compared with microseismic events. It shows that stress concentration can cause micro-seismic events regional aggregation.

scholarly journals Crystal Structure and Computational Study on Methyl-3-Aminothiophene-2-Carboxylate

Crystals ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 19 ◽  
Author(s):  
Yaping Tao ◽  
Ligang Han ◽  
Andong Sun ◽  
Kexi Sun ◽  
Qian Zhang ◽  
...  
Keyword(s):  
Crystal Packing ◽  
Computational Study ◽  
Three Dimensional ◽  
X Ray Diffraction ◽  
Dispersion Energy ◽  
Monoclinic Crystal ◽  
Hydrogen Bond Interactions ◽  
Calculation Results ◽  
Reduced Density Gradient ◽  
Reduced Density

Methyl-3-aminothiophene-2-carboxylate (matc) is a key intermediate in organic synthesis, medicine, dyes, and pesticides. Single crystal X-ray diffraction analysis reveals that matc crystallizes in the monoclinic crystal system P21/c space group. Three matc molecules in the symmetric unit are crystallographically different and further linked through the N–H⋯O and N–H⋯N hydrogen bond interactions along with weak C–H⋯S and C–H⋯Cg interactions, which is verified by the three-dimensional Hirshfeld surface, two-dimensional fingerprint plot, and reduced density gradient (RDG) analysis. The interaction energies within crystal packing are visualized through dispersion, electrostatic, and total energies using three-dimensional energy-framework analyses. The dispersion energy dominates in crystal packing. To better understand the properties of matc, electrostatic potential (ESP) and frontier molecular orbitals (FMO) were also calculated and discussed. Experimental and calculation results suggested that amino and carboxyl groups can participate in various inter- and intra-interactions.

scholarly journals Study of the Effect of Centrifugal Force on Rotor Blade Icing Process

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Zhengzhi Wang ◽  
Chunling Zhu
Keyword(s):  
Numerical Simulation ◽  
Centrifugal Force ◽  
Rotor Blade ◽  
Flow Direction ◽  
Three Dimensional ◽  
Simulation Method ◽  
Two Phase ◽  
Numerical Simulation Method ◽  
Calculation Results ◽  
Flow Field Characteristics

In view of the rotor icing problems, the influence of centrifugal force on rotor blade icing is investigated. A numerical simulation method of three-dimensional rotor blade icing is presented. Body-fitted grids around the rotor blade are generated using overlapping grid technology and rotor flow field characteristics are obtained by solving N-S equations. According to Eulerian two-phase flow, the droplet trajectories are calculated and droplet impingement characteristics are obtained. The mass and energy conservation equations of ice accretion model are established and a new calculation method of runback water mass based on shear stress and centrifugal force is proposed to simulate water flow and ice shape. The calculation results are compared with available experimental results in order to verify the correctness of the numerical simulation method. The influence of centrifugal force on rotor icing is calculated. The results show that the flow direction and distribution of liquid water on rotor surfaces change under the action of centrifugal force, which lead to the increasing of icing at the stagnation point and the decreasing of icing on both frozen limitations.

The Uneven Settlement Cause and Settlement Prediction of Xi Ying Sluice

2015 ◽  
Vol 733 ◽  
pp. 116-119
Author(s):  
Qing Yuan Zhu ◽  
Li Ting Qiu ◽  
Ting Jiang
Keyword(s):  
Three Dimensional ◽  
Normal Operation ◽  
Wall Structure ◽  
Construction Period ◽  
Settlement Prediction ◽  
Concrete Pile ◽  
Operation Period ◽  
Dimensional Finite Element ◽  
Three Dimensional Finite Element ◽  
Design Construction

Xi Ying sluice built in Xishi River, Changzhou City, is a single span sluice with width of 6m. The chamber is pier wall structure of depressed reinforced concrete floor, when the chamber had a filling and discharging water during construction period, we found that the chamber appeared large uneven subsidence. According to the design, construction and other specific circumstances of Xi Ying sluice, by using three-dimensional finite element method to calculate and analyzed the settlement of the sluice, we studied on the genesis of the uneven settlement and predicted the settlement after the running. Analysis shows that the chamber of the uneven settlement is due to the jacking effect of concrete pile. The settlement has been basically completed caused by chamber weight, there will not be a substantial settlement; In the case of blocking water during operation period, chamber’s settlement increment outside the river side and inside the river side are respectively 0.3mm and 0.4mm; through processing, the settlement of chamber won’t affect the normal operation of sluice.

Application of the Mechanical Impedance of Body Arm Movement Based on the Virtual Tennis System

2013 ◽  
Vol 791-793 ◽  
pp. 1436-1440
Author(s):  
Ling Hang Yang
Keyword(s):  
Virtual Reality ◽  
Three Dimensional ◽  
Arm Movement ◽  
Mechanical Impedance ◽  
Simulation Software ◽  
Computer Hardware ◽  
Calculation Results ◽  
Virtual System ◽  
Dimensional Simulation ◽  
Theoretical Results

With the development of computer hardware and software technology, virtual reality technology of computer has been widely used in various fields. Virtual teaching process is one of the main applications of virtual reality computer technology. Tennis is one of the most common sports. Tennis process mainly includes the process of catching a ball, serving a ball and hitting a ball. Virtual process of tennis system must establish an accurate numerical simulation model to calculate the mechanical impedance during the arm movement of human. According to this, it builds a model of the mechanical impedance of human arm in tennis virtual system using three-dimensional simulation software in this paper and gets the curve of mechanical impedance through the simulation. Finally, the article compares calculation results with the theoretical results and concludes that the theoretical results and simulation results are basically consistent which provide a theoretical reference for the design of the development of virtual system for the human.

Investigation of thermal stresses in an arch dam on a three-dimensional model

1974 ◽  
Vol 8 (5) ◽  
pp. 433-437
Author(s):  
Yu. I. Kononov ◽  
E. M. Frolov ◽  
S. E. Fomin ◽  
V. I. Bronshtein
Keyword(s):  
Thermal Stresses ◽  
Three Dimensional ◽  
Arch Dam ◽  
Dimensional Model ◽  
Three Dimensional Model

scholarly journals Numerical Analyses on the Stability of a Deep Coalmine Roadway Passing through a Fault Zone: A Case Study of the Gugui Coalfield in China

Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2114
Author(s):  
Yongshui Kang ◽  
Congcong Hou ◽  
Jingyi Liu ◽  
Zhi Geng ◽  
Jianben Chen ◽  
...  
Keyword(s):  
Fault Zone ◽  
Distinct Element ◽  
Three Dimensional ◽  
Tectonic Stress ◽  
Three Dimensional Model ◽  
Support Strategy ◽  
Failure Theory ◽  
Calculation Results ◽  
Pass Through ◽  
The Stability

Massive deformation often occurs when deep coalmine roadways pass through a fault zone due to the poor integrity of rock mass and high tectonic stress. To study deformation characteristics of the surrounding rock in the fault zone of a coalmine, a roadway passing through the FD1041 fault zone in China’s Gugui coalfield was investigated in this research. The geo-stress characteristics of this fault zone were analyzed based on the Mohr failure theory. Furthermore, a three-dimensional model for the experimental roadway in the FD1041 fault zone was built and calculated by a numerical program based on the distinct element method. Stability conditions of the roadway, using several types of support methods, were calculated and compared. Calculation results indicated that pre-grouting provides favorable conditions for the stability of a roadway in a fault zone. Finally, an optimized support strategy was proposed and implemented in the experimental roadway. Monitored results demonstrated that the optimized support strategy is appropriate for this fault zone.

A Small PWR-Core Physical Calculation Based on PWR-Core Analysis Code CORAL

2021 ◽  
Author(s):  
Wen Yang ◽  
Lun Zhou ◽  
Junrong Qiu ◽  
Yun Tai
Keyword(s):  
Density Distribution ◽  
Power Distribution ◽  
Channel Model ◽  
Three Dimensional ◽  
Least Square ◽  
Object Oriented Programming ◽  
Core Analysis ◽  
Fuel Temperature ◽  
Fuel Assemblies ◽  
Calculation Results

Abstract Three dimensional PWR-core analysis code CORAL is developed by Wuhan Second Ship Design and Research Institute. This code provides basic functions including three-dimensional power distribution, fine power reconstruction, fuel temperature distribution, critical search, control rod worth, reactivity coefficients, burnup and nuclide density distribution, etc. CORAL employ nodal expansion method to solve neutron diffusion equation, and the least square method is used to achieve few group constants, and sub-channel model and one-dimensional heat transfer is used to calculate fuel temperature and coolant density distribution, and burnup distribution and nuclide nuclear density could be obtained by solving macro-depletion and micro-depletion equation. The CORAL code is convenient to update and maintain in consider of modular, object-oriented programming technology. In order to analyze the computational accuracy of the CORAL code in small PWR-core and its capability to deal with heterogeneous, calculation analysis are carried out based on the material and geometry parameters of the SMART core. The core has 57 fuel assemblies, with 8, 20 or 24 gadolinium rods arranged in the fuel assemblies. In this paper, a quantitative comparison and analysis of the small PWR problem calculation results are carried out. Numerical results, including effective multiplication factor, assembly power distribution and pin power distribution, all agree well with the calculation results of OpenMC or Bamboo at both hot zero-power (HZP) and hot full-power (HFP) conditions.

A Model of Bubble Nucleation on a Micro Line Heater

1999 ◽  
Vol 121 (1) ◽  
pp. 220-225 ◽  
Author(s):  
S.-D. Oh ◽  
S. S. Seung ◽  
H. Y. Kwak
Keyword(s):  
Bubble Formation ◽  
Three Dimensional ◽  
Bubble Nucleation ◽  
Heat Diffusion ◽  
Nucleation Theory ◽  
Molecular Cluster ◽  
Heater Surface ◽  
Calculation Results ◽  
Critical Bubble ◽  
Superheat Limit

The bubble nucleation mechanism on a cavity-free micro line heater surface was studied by using the molecular cluster model. A finite difference numerical scheme for the three-dimensional transient conduction equation for the liquid was employed to estimate the superheated volume where homogeneous bubble nucleation could occur due to heat diffusion from the heater to the liquid. Calculation results revealed that bubble formation on the heater is possible when the temperature at the hottest point in the heater is greater than the superheat limit of the liquid by 6°C–12°C, which is in agreement with the experimental results. Also it was found that the classical bubble nucleation theory breaks down near the critical point where the radius of the critical bubble is below 100 nm.

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