期刊文献+
共找到13,224篇文章
< 1 2 250 >
每页显示 20 50 100
Effect of Bogie Cavity End Wall Inclination on Flow Field and Aerodynamic Noise in the Bogie Region of High-Speed Trains
1
作者 Jiawei Shi Jiye Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期2175-2195,共21页
Combining the detached eddy simulation(DES)method and Ffowcs Williams-Hawkings(FW-H)equation,the effect of bogie cavity end wall inclination on the flow field and aerodynamic noise in the bogie region is numerically s... Combining the detached eddy simulation(DES)method and Ffowcs Williams-Hawkings(FW-H)equation,the effect of bogie cavity end wall inclination on the flow field and aerodynamic noise in the bogie region is numerically studied.First,the simulation is conducted based on a simplified cavity-bogie model,including five cases with different inclination angles of the front and rear walls of the cavity.By comparing and analyzing the flow field and acoustic results of the five cases,the influence of the regularity and mechanism of the bogie cavity end wall inclination on the flow field and the aerodynamic noise of the bogie region are revealed.Then,the noise reduction strategy determined by the results of the simplified cavity-bogie model is applied to a three-car marshaling train model to verify its effectiveness when applied to the real train.The results reveal that the forward inclination of the cavity front wall enlarges the influence area of shear vortex structures formed at the leading edge of the cavity and intensifies the interaction between the vortex structures and the front wheelset,frontmotor,and front gearbox,resulting in the increase of the aerodynamic noise generated by the bogie itself.The backward inclination of the cavity rear wall is conducive to guiding the vortex structures flow out of the cavity and weakening the interaction between the shear vortex structures and the cavity rear wall,leading to the reduction of the aerodynamic noise generated by the bogie cavity.Inclining the rear end wall of the foremost bogie cavity of the head car is a feasible aerodynamic noise reduction measure for high-speed trains. 展开更多
关键词 BOGIE cavity flow aerodynamic noise end wall inclination
下载PDF
Numerical parametric study on the influence of location and inclination of large-scale asperities on the shear strength of concreterock interfaces of small buttress dams
2
作者 Dipen Bista Adrian Ulfberg +3 位作者 Leif Lia Jaime Gonzalez-Libreros Fredrik Johansson Gabriel Sas 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第10期4319-4329,共11页
When assessing the sliding stability of a concrete dam,the influence of large-scale asperities in the sliding plane is often ignored due to limitations of the analytical rigid body assessment methods provided by curre... When assessing the sliding stability of a concrete dam,the influence of large-scale asperities in the sliding plane is often ignored due to limitations of the analytical rigid body assessment methods provided by current dam assessment guidelines.However,these asperities can potentially improve the load capacity of a concrete dam in terms of sliding stability.Although their influence in a sliding plane has been thoroughly studied for direct shear,their influence under eccentric loading,as in the case of dams,is unknown.This paper presents the results of a parametric study that used finite element analysis(FEA)to investigate the influence of large-scale asperities on the load capacity of small buttress dams.By varying the inclination and location of an asperity located in the concrete-rock interface along with the strength of the rock foundation material,transitions between different failure modes and correlations between the load capacity and the varied parameters were observed.The results indicated that the inclination of the asperity had a significant impact on the failure mode.When the inclinationwas 30and greater,interlocking occurred between the dam and foundation and the governing failure modes were either rupture of the dam body or asperity.When the asperity inclination was significant enough to provide interlocking,the load capacity of the dam was impacted by the strength of the rock in the foundation through influencing the load capacity of the asperity.The location of the asperity along the concrete-rock interface did not affect the failure mode,except for when the asperity was located at the toe of the dam,but had an influence on the load capacity when the failure occurred by rupture of the buttress or by sliding.By accounting for a single large-scale asperity in the concrete-rock interface of the analysed dam,a horizontal load capacity increase of 30%e160%was obtained,depending on the inclination and location of the asperity and the strength of the foundation material. 展开更多
关键词 Concrete dam Buttress dam SLIDING Shear strength Concrete-rock interface Asperity inclination Asperity location
下载PDF
Effect of Nozzle Inclination Angle on Fuel-Air Mixing and Combustion in a Heavy Fuel Engine
3
作者 Zhigang Wang Bin Zheng +4 位作者 Peidong Zhao Baoli Wang Fanyan Meng Wenke Xu Jian Meng 《Fluid Dynamics & Materials Processing》 EI 2024年第2期365-382,共18页
Heavy-fuel engines are widely used in UAVs(Unmanned Autonomous Vehicles)because of their reliability and high-power density.In this study,a combustion model for an in-cylinder direct injection engine has been imple-me... Heavy-fuel engines are widely used in UAVs(Unmanned Autonomous Vehicles)because of their reliability and high-power density.In this study,a combustion model for an in-cylinder direct injection engine has been imple-mented using the AVL FIRE software.The effects of the angle of nozzle inclination on fuel evaporation,mixture distribution,and combustion in the engine cylinder have been systematically studied at 5500 r/min and consider-ing full load cruise conditions.According to the results,as the angle of nozzle inclination increases,the maximum combustion explosion pressure in the cylinderfirst increases and then it decreases.When the angle of nozzle incli-nation is less than 45°,the quality of the mixture in the cylinder and the combustion performance can be improved by increasing the angle.When the angle of nozzle inclination is greater than 45°,however,the mixture unevenness increases slightly with the angle,leading to a deterioration of the combustion performances.When the angle of nozzle inclination is between 35°and 55°,the overall combustion performance of the engine is rela-tively good.When the angle of nozzle inclination is 45°,the combustion chamber’s geometry and the cylinder’s airflow are well matched with the fuel spray,and the mixture quality is the best.Compared with 25°,the peak heat release rate increases by 20%,and the maximum combustion burst pressure increases by 5.5%. 展开更多
关键词 Aviation heavy fuel piston engine nozzle inclination angle COMBUSTION fuel-air mixing
下载PDF
Influence of variable viscosity and double diffusion on the convective stability of a nanofluid flow in an inclined porous channel 被引量:1
4
作者 N.HUMNEKAR D.SRINIVASACHARYA 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第3期563-580,共18页
The influence of variable viscosity and double diffusion on the convective stability of a nanofluid flow in an inclined porous channel is investigated.The DarcyBrinkman model is used to characterize the fluid flow dyn... The influence of variable viscosity and double diffusion on the convective stability of a nanofluid flow in an inclined porous channel is investigated.The DarcyBrinkman model is used to characterize the fluid flow dynamics in porous materials.The analytical solutions are obtained for the unidirectional and completely developed flow.Based on a normal mode analysis,the generalized eigenvalue problem under a perturbed state is solved.The eigenvalue problem is then solved by the spectral method.Finally,the critical Rayleigh number with the corresponding wavenumber is evaluated at the assigned values of the other flow-governing parameters.The results show that increasing the Darcy number,the Lewis number,the Dufour parameter,or the Soret parameter increases the stability of the system,whereas increasing the inclination angle of the channel destabilizes the flow.Besides,the flow is the most unstable when the channel is vertically oriented. 展开更多
关键词 NANOFLUID inclined channel variable viscosity linear stability double dif-fusion porous medium
下载PDF
Experimental Study on Effect of Inclination Angle on Bubble Collapse near Attached Air Bubble
5
作者 WANG Jia-xia WU Shi-zeng +2 位作者 LIU Kun JIANG Ming-zuo WANG Zi-li 《China Ocean Engineering》 SCIE EI CSCD 2023年第5期753-767,共15页
Experiments were conducted to investigate the dynamics of an oscillating bubble generated by a spark in the presence of an inclined attached air bubble.The study primarily focused on the influence of the inclination a... Experiments were conducted to investigate the dynamics of an oscillating bubble generated by a spark in the presence of an inclined attached air bubble.The study primarily focused on the influence of the inclination angle on the behavior of bubble jetting orientation,air bubble shape modes,and motion characteristics of the interaction between the two bubbles.Various complex bubble jetting behaviors were observed,including the presence of multiple types of bubble jetting directions,bubble splitting,and multidirectional jets.Four types of air bubble shapes were defined,namely inclined cup cover-shaped(with and without splitting),double-peaked cup cover-shaped,and inclined L-shaped air bubbles.The formation of different types of bubble jets was analyzed using the vector synthesis principle of the Bjerknes force exerted by the inclined attached air bubble and a steel plate.To describe the diverse orientations of bubble jetting and air bubble shapes,new parameters namely the dimensionless spark bubble oscillation time T^(*)and volume ratio V^(*)that consider the inclination angle are proposed.The findings of this investigation contribute to the existing knowledge and have the potential to further enhance methods for mitigating cavitation damage in marine,hydraulic machinery systems,and medical fields.l fields. 展开更多
关键词 spark-generated bubble experiment inclination angle bubble jet air bubble shape bubble dynamics
下载PDF
Influence of the Inclination Angle on Mixed Convection and Heat Transfer in a“T”Shaped Double Enclosure
6
作者 M’Barka Mourabit Meryam Meknassi +3 位作者 Soukaina Fekkar Soumia Mordane Hicham Rouijaa El Alami Semma 《Fluid Dynamics & Materials Processing》 EI 2023年第7期1753-1774,共22页
The effect of the tilt angle on mixed convection and related heat transfer in a“T”shaped double enclosure with four heated obstacles on the bottom surface is numerically investigated.The considered obstacles are con... The effect of the tilt angle on mixed convection and related heat transfer in a“T”shaped double enclosure with four heated obstacles on the bottom surface is numerically investigated.The considered obstacles are constantly kept at a relatively high(fixed)temperature,while the cavity’s upper wall is cooled.The finite volume approach is used to solve the mass,momentum,and energy equations with the SIMPLEC algorithm being exploited to deal with the pressure-velocity coupling.Emphasis is put on the influence of the tilt angle on the solution symmetry,flow structure,and heat exchange through the walls.The following parameters and related ranges are considered:Rayleigh number 104≤Ra≤5.105,tilt angle 0°≤φ≤90°,Reynolds number 100≤Re≤1000,Prandtl number Pr=0.72,block height B=0.5,opening width C=0.15,and distance between blocks D=0.5.The results reveal different branches of solutions on varying Re andφ.They also show that the symmetry of the solution regarding the P_(2)axis is retained for all cases with no tilt and for values of Re between 100 and 1000. 展开更多
关键词 Mixed convection heat transfer inclination angle “T”shaped double cavity
下载PDF
A hybrid ventilation scheme applied to bidirectional excavation tunnel construction with a long inclined shaft
7
作者 YANG Wei-chao WANG Jian +3 位作者 DENG E LIU Yi-kang LUO Lu-sen YANG Jia 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第9期3187-3205,共19页
The breakage and bending of ducts result in a difficulty to cope with ventilation issues in bidirectional excavation tunnels with a long inclined shaft using a single ventilation method based on ducts.To discuss the h... The breakage and bending of ducts result in a difficulty to cope with ventilation issues in bidirectional excavation tunnels with a long inclined shaft using a single ventilation method based on ducts.To discuss the hybrid ventilation system applied in bidirectional excavation tunnels with a long inclined shaft,this study has established a full-scale computational fluid dynamics model based on field tests,the Poly-Hexcore method,and the sliding mesh technique.The distribution of wind speed,temperature field,and CO in the tunnel are taken as indices to compare the ventilation efficiency of three ventilation systems(duct,duct-ventilation shaft,duct–ventilated shaft-axial fan).The results show that the hybrid ventilation scheme based on duct-ventilation shaft–axial fan performs the best among the three ventilation systems.Compared to the duct,the wind speed and cooling rate in the tunnel are enhanced by 7.5%–30.6%and 14.1%–17.7%,respectively,for the duct-vent shaft-axial fan condition,and the volume fractions of CO are reduced by 26.9%–73.9%.This contributes to the effective design of combined ventilation for bidirectional excavation tunnels with an inclined shaft,ultimately improving the air quality within the tunnel. 展开更多
关键词 bidirectional excavation tunnel inclined shaft hybrid ventilation scheme computational fluid dynamics ventilation efficiency
下载PDF
Effect of eccentric and inclined loading on the bearing capacity of strip footing placed on rock mass
8
作者 Shuvankar DAS Debarghya CHAKRABORTY 《Journal of Mountain Science》 SCIE CSCD 2024年第1期292-312,共21页
This paper deals with the bearing capacity determination of strip footing on a rock mass in hilly area by considering the influence of inclined and eccentric loading. Applying the generalized HoekBrown failure criteri... This paper deals with the bearing capacity determination of strip footing on a rock mass in hilly area by considering the influence of inclined and eccentric loading. Applying the generalized HoekBrown failure criterion, the failure behavior of the rock mass is modeled with the help of the power cone programming in the lower bound finite element limit analysis framework. Using bearing capacity factor(Ns), the change in bearing capacity of the strip footing due to the occurrence of eccentrically inclined loading is presented. The variations of the magnitude of Ns are obtained by examining the effects of the Hoek-Brown rock mass strength parameters(uniaxial compressive strength(sci), disturbance factor(D), rock parameter(mi), and Geological Strength Index(GSI)) in the presence of different magnitudes of eccentricity(e) and inclination angle(λ) with respect to the vertical plane, and presented as design charts. Both the inclined loading modes, i.e., inclination towards the center of strip footing(+λ) and inclination away from the center of strip footing(-λ), are adopted to perform the investigation. In addition, the correlation between the input parameters and the corresponding output is developed by utilizing the artificial neural network(ANN). Additionally, from sensitivity analysis, it is observed that inclination angle(λ) is the most sensitive parameter. For practicing engineers, the obtained design equation and design charts can be beneficial to understand the bearing capacity variation in the existence of eccentrically inclined loading in mountain areas. 展开更多
关键词 Eccentric and inclined Power cone programming Rock mass Limit analysis Artificial neural network
下载PDF
Three-Dimensional Convection in an Inclined Porous Layer Subjected to a Vertical Temperature Gradient
9
作者 Ivan Shubenkov Tatyana Lyubimova Evgeny Sadilov 《Fluid Dynamics & Materials Processing》 EI 2024年第9期1957-1970,共14页
In this paper,we study the onset and development of three-dimensional convection in a tilted porous layer saturated with a liquid.The layer is subjected to a gravitational field and a strictly vertical temperature gra... In this paper,we study the onset and development of three-dimensional convection in a tilted porous layer saturated with a liquid.The layer is subjected to a gravitational field and a strictly vertical temperature gradient.Typically,problems of thermal convection in tilted porous media saturated with a liquid are studied by assuming constant different temperatures at the boundaries of the layer,which prevent these systems from supporting conductive(non-convective)states.The boundary conditions considered in the present work allow a conductive state and are representative of typical geological applications.In an earlier work,we carried out a linear stability analysis of the conductive state.It was shown that at any layer tilt angles,the most dangerous type of disturbances are longitudinal rolls.Moreover,a non-zero velocity component exists in z-direction.In the present work,threedimensional non-linear convection regimes are studied.The original three-dimensional problem is reduced to two-dimensional one with an analytical expression for the velocity z-component v_(z)=v_(z)(x,y).It is shown that the critical Rayleigh number values obtained through numerical solutions of the obtained 2D problem by a finite difference method for different layer inclination angles,are in a good agreement with those predicted by the linear theory.The number of convective rolls realized in nonlinear calculations also fits the linear theory predictions for a given cavity geometry.Calculations carried out at low supercriticalities show that a direct bifurcation takes place.With increasing supercriticality,no transitions to other convective regimes are detected.The situation studied in this problem can be observed in oil-bearing rock formations under the influence of a geothermal temperature gradient,where the ensuing fluid convection can affect the distribution of oil throughout the layer. 展开更多
关键词 Thermal convection inclined layer porous media vertical temperature gradient
下载PDF
Experimental study on seismic reinforcement of bridge foundation on silty clay landslide with inclined interlayer
10
作者 Lei Da Xiao Hanmo +3 位作者 Ran Jianhua Luo Bin Jiang Guanlu Xue Tianlang 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期193-207,共15页
A shaking table test for a bridge foundation reinforced by anti-slide piles on a silty clay landslide model with an inclined interlayer was performed.The deformation characteristics of the bridge foundation piles and ... A shaking table test for a bridge foundation reinforced by anti-slide piles on a silty clay landslide model with an inclined interlayer was performed.The deformation characteristics of the bridge foundation piles and anti-slide piles were analyzed in different loading conditions.The dynamic response law of a silty clay landslide with an inclined interlayer was summarized.The spacing between the rear anti-slide piles and bridge foundation should be reasonably controlled according to the seismic fortification requirements,to avoid the two peaks in the forced deformation of the bridge foundation piles.The“blocking effect”of the bridge foundation piles reduced the deformation of the forward anti-slide piles.The stress-strain response of silty clay was intensified as the vibration wave field appeared on the slope.Since the vibration intensified,the thrust distribution of the landslide underwent a process of shifting from triangle to inverted trapezoid,the difference in the acceleration response between the bearing platform and silty clay landslide tended to decrease,and the spectrum amplitude near the natural vibration frequency increased.The rear anti-slide piles were able to slow down the shear deformation of the soil in front of the piles and avoid excessive acceleration response of the bridge foundation piles. 展开更多
关键词 silty clay landslide inclined interlayer shaking table test anti-slide pile bridge foundation pile
下载PDF
Scattering of Water Waves by Dual Symmetric Inclined Floating Porous Barriers Using the DBEM
11
作者 WANG Li-xian DENG Yan-wen +1 位作者 YE Yang-sha DENG Zheng-zhi 《China Ocean Engineering》 SCIE EI CSCD 2024年第1期156-168,共13页
The scattering of normally incident water waves by two surface-piercing inclined perforated barriers in water with a uniform finite depth is investigated within the framework of linear water wave theory.Considering th... The scattering of normally incident water waves by two surface-piercing inclined perforated barriers in water with a uniform finite depth is investigated within the framework of linear water wave theory.Considering that thin barriers are zero-thickness,a novel numerical method involving the the coupling of the dual boundary element method(DBEM)with damping layers is applied.In order to effectively damp out the reflected waves,two damping layers,instead of pseudoboundaries are implemented near the two side boundaries of the computational domain.Thus,the modified linearized free surface boundary conditions are formulated and used for solving both the ordinary boundary integral equation as well as the hypersingular boundary integral equation for degenerate boundaries.The newly developed numerical method is validated against analytical methods using the matched eigenfunction expansion method for the special case of two vertical barriers or the inclined angle to the vertical being zero.The influence of the length of the two damping layers has been discussed.Moreover,these findings are also validated against previous results for several cases.After validation,the numerical results for the reflection coefficient,transmission coefficient and dissipation coefficient are obtained by varying the inclination angle and porosity-effect parameter.The effects of both the inclination angle and the porosity on the amplitudes of wave forces acting on both the front and rear barriers are also investigated.It is found that the effect of the inclination angle mainly shifts the location of the extremal values of the reflection and the transmission coefficients.Additionally,a moderate value of the porosity-parameter is quite effective at dissipating wave energy and mitigating the wave loads on dual barriers. 展开更多
关键词 dual boundary element method inclined perforated floating breakwater reflection coefficient transmission coefficient damping layer
下载PDF
Hydrodynamic characteristics and particle tracking of 90° lateral intakes at an inclined river slope
12
作者 Wei He Si-yuan Feng +4 位作者 Jian Zhang Hong-wu Tang Yang Xiao Sheng Chen Chun-sheng Liu 《Water Science and Engineering》 EI CAS CSCD 2024年第2期197-208,共12页
Lateral intakes are common in rivers.The pump effciency and sediment deposition are determined by the local hydrodynamic characteristics and mainstream division width.The hydraulic characteristics of lateral withdrawa... Lateral intakes are common in rivers.The pump effciency and sediment deposition are determined by the local hydrodynamic characteristics and mainstream division width.The hydraulic characteristics of lateral withdrawal from inclined river slopes at different intake elevations should be investigated.Meanwhile,the division width exhibits significant vertical non-uniformity at an inclined river slope,which should be clarified.Hence,a three-dimensional(3-D)hydrodynamic and particle-tracking model was developed with the Open Source Field Operation and Manipulation(Open FOAM),and the model was validated with physical model tests for 90°lateral withdrawal from an inclined side bank.The flow fields,withdrawal sources,and division widths were investigated with different intake bottom elevations,withdrawal discharges,and main channel velocities.This study showed that under inclined side bank conditions,water entered the intake at an oblique angle,causing significant 3-D spiral flows in the intake rather than two-dimensional closed recirculation.A lower withdrawal discharge,a lower bottom elevation of the intake,or a higher main channel velocity could further strengthen this phenomenon.The average division width and turbulent kinetic energy were smaller under inclined side bank conditions than under vertical bank conditions.With a low intake bottom elevation,a low withdrawal discharge,or a high main channel velocity,the sources of lateral withdrawal were in similar ranges near the local inclined bank in the vertical direction.Under inclined slope conditions,sediment deposition near the intake entrance could be reduced,compared to that under vertical slope conditions.The results provide hydrodynamic and sediment references for engineering designs for natural rivers with inclined terrains. 展开更多
关键词 Lateral withdrawal Hydrodynamic characteristics Particle tracking inclined river slope Bottom elevation of intake OPENFOAM
下载PDF
Disasters of gas-coal spontaneous combustion in goaf of steeply inclined extra-thick coal seams
13
作者 Qiming Zhang Enyuan Wang +2 位作者 Xiaojun Feng Shuxin Liu Dong Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第10期4141-4153,共13页
In light of the escalating global energy imperatives,mining of challenging-to-access resources,such as steeply inclined extra-thick coal seams(SIEC),has emerged as one of the future trends within the domain of energy ... In light of the escalating global energy imperatives,mining of challenging-to-access resources,such as steeply inclined extra-thick coal seams(SIEC),has emerged as one of the future trends within the domain of energy advancement.However,there is a risk of gas and coal spontaneous combustion coupling disasters(GCC)within the goaf of SIEC due to the complex goaf structure engendered by the unique mining methodologies of SIEC.To ensure that SIEC is mined safely and efficiently,this study conducts research on the GCC within the goaf of SIEC using field observation,theoretical analysis,and numerical modeling.The results demonstrate that the dip angle,the structural dimensions in terms of width-to-length ratio,and compressive strength of the overlying rock are the key factors contributing to the goaf instability of SIEC.The gangue was asymmetrically filled,primarily accumulating within the central and lower portions of the goaf,and the filling height increased proportionally with the advancing caving height,the expansion coefficient,and the thickness of the surrounding rock formation.The GCC occurs in the goaf of SIEC,with an air-return side range of 41 m and an air-intake side range of 14 m,at the intersection area of the“<”-shaped oxygen concentration distribution(coal spontaneous combustion)and the“>”-shaped gas concentration distribution(gas explosion).The optimal nitrogen flow rate is 1000 m3/h with an injection port situated 25 m away from the working face for the highest nitrogen diffusion efficacy and lowest risk of gas explosion,coal spontaneous combustion,and GCC.It has significant engineering applications for ensuring the safe mining of SIEC threatened by the GCC. 展开更多
关键词 Steeply inclined extra-thick coal seams Gas explosion Coal spontaneous combustion Coupling disaster Numerical simulation
下载PDF
Research on the mechanism of rockburst induced by mined coal-rock linkage of sharply inclined coal seams
14
作者 Xingping Lai Huicong Xu +4 位作者 Pengfei Shan Qinxin Hu Weixi Ding Shangtong Yang Zhongming Yan 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期929-942,共14页
In recent years,the mining depth of steeply inclined coal seams in the Urumqi mining area has gradually increased.Local deformation of mining coal-rock results in frequent rockbursts.This has become a critical issue t... In recent years,the mining depth of steeply inclined coal seams in the Urumqi mining area has gradually increased.Local deformation of mining coal-rock results in frequent rockbursts.This has become a critical issue that affects the safe mining of deep,steeply inclined coal seams.In this work,we adopt a perspective centered on localized deformation in coal-rock mining and systematically combine theoretical analyses and extensive data mining of voluminous microseismic data.We describe a mechanical model for the urgently inclined mining of both the sandwiched rock pillar and the roof,explaining the mechanical response behavior of key disaster-prone zones within the deep working face,affected by the dynamics of deep mining.By exploring the spatial correlation inherent in extensive microseismic data,we delineate the“time-space”response relationship that governs the dynamic failure of coal-rock during the progression of the sharply inclined working face.The results disclose that(1)the distinctive coal-rock occurrence structure characterized by a“sandwiched rock pillar-B6 roof”constitutes the origin of rockburst in the southern mining area of the Wudong Coal Mine,with both elements presenting different degrees of deformation localization with increasing mining depth.(2)As mining depth increases,the bending deformation and energy accumulation within the rock pillar and roof show nonlinear acceleration.The localized deformation of deep,steeply inclined coal-rock engenders the spatial superposition of squeezing and prying effects in both the strike and dip directions,increasing the energy distribution disparity and stress asymmetry of the“sandwiched rock pillar-B3+6 coal seam-B6 roof”configuration.This makes worse the propensity for frequent dynamic disasters in the working face.(3)The developed high-energy distortion zone“inner-outer”control technology effectively reduces high stress concentration and energy distortion in the surrounding rock.After implementation,the average apparent resistivity in the rock pillar and B6 roof substantially increased by 430%and 300%,respectively,thus guaranteeing the safe and efficient development of steeply inclined coal seams. 展开更多
关键词 steeply inclined coal seam localized deformation mechanism of induced rockburst prevention and control of rockburst
下载PDF
Exploring mechanism of hidden,steep obliquely inclined bedding landslides using a 3DEC model:A case study of the Shanyang landslide in Shaanxi Province,China
15
作者 Jia-yun Wang Zi-long Wu +3 位作者 Xiao-ya Shi Long-wei Yang Rui-ping Liu Na Lu 《China Geology》 CAS CSCD 2024年第2期303-314,I0001-I0003,共15页
Catastrophic geological disasters frequently occur on slopes with obliquely inclined bedding structures(also referred to as obliquely inclined bedding slopes),where the apparent dip sliding is not readily visible.This... Catastrophic geological disasters frequently occur on slopes with obliquely inclined bedding structures(also referred to as obliquely inclined bedding slopes),where the apparent dip sliding is not readily visible.This phenomenon has become a focal point in landslide research.Yet,there is a lack of studies on the failure modes and mechanisms of hidden,steep obliquely inclined bedding slopes.This study investigated the Shanyang landslide in Shaanxi Province,China.Using field investigations,laboratory tests of geotechnical parameters,and the 3DEC software,this study developed a numerical model of the landslide to analyze the failure process of such slopes.The findings indicate that the Shanyang landslide primarily crept along a weak interlayer under the action of gravity.The landslide,initially following a dip angle with the support of a stable inclined rock mass,shifted direction under the influence of argillization in the weak interlayer,moving towards the apparent dip angle.The slide resistance effect of the karstic dissolution zone was increasingly significant during this process,with lateral friction being the primary resistance force.A reduction in the lateral friction due to karstic dissolution made the apparent dip sliding characteristics of the Shanyang landslide more pronounced.Notably,deformations such as bending and uplift at the slope’s foot suggest that the main slide resistance shifts from lateral friction within the karstic dissolution zone to the slope foot’s resistance force,leading to the eventual buckling failure of the landslide.This study unveils a novel failure mode of apparent dip creep-buckling in the Shanyang landslide,highlighting the critical role of lateral friction from the karstic dissolution zone in its failure mechanism.These insights offer a valuable reference for mitigating risks and preventing disasters related to obliquely inclined bedding landslides. 展开更多
关键词 LANDSLIDE Steep obliquely inclined bedding slope Failure mode Failure mechanism Apparent dip creep-buckling Lateral friction 3DEC model Landslide numerical model Geological hazards survey engineering
下载PDF
Inclination Towards Good——An Analysis of and Comparison Between the Characters in the Scarlet Letter
16
作者 高芬 《陕西师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2002年第S3期276-280,共5页
Nathaniel Hawthorne not only strongly condemns the belief that men are more evil than good, but also conveys the inclination towards good through the Scarlet Letter. The characters like Hester Prynne, Dimmesdale, ... Nathaniel Hawthorne not only strongly condemns the belief that men are more evil than good, but also conveys the inclination towards good through the Scarlet Letter. The characters like Hester Prynne, Dimmesdale, Chillingworth and even the community are the specific examples. Despite the fact that good and evil coexist in human nature, human beings are liable to be strongly affected and controlled by the striving towards good. 展开更多
关键词 inclination GOOD sin HESTER DIMMESDALE CHILLINGWORTH Community
下载PDF
Rice leaf inclination2, a VIN3-1ike protein, regulates leaf angle through modulating cell division of the collar 被引量:36
17
作者 Shu-Qing Zhao Jiang Hu +2 位作者 Long-Biao Guo Qian Qian Hong-Wei Xue 《Cell Research》 SCIE CAS CSCD 2010年第8期935-947,共13页
As an important agronomic trait, inclination of leaves is crucial Ior crop architecture and grain yields. 10 understand the molecular mechanism controlling rice leaf angles, one rice leaf inclination2 (1c2, three all... As an important agronomic trait, inclination of leaves is crucial Ior crop architecture and grain yields. 10 understand the molecular mechanism controlling rice leaf angles, one rice leaf inclination2 (1c2, three alleles) mutant was identified and functionally characterized. Compared to wild-type plants, lc2 mutants have enlarged leaf angles due to increased cell division in the adaxial epidermis of lamina joint. The LC2 gene was isolated through positional cloning, and encodes a vernalization insensitive 3-like protein. Complementary expression of LC2 reversed the enlarged leaf angles of lc2 plants, confirming its role in controlling leaf inclination. LC2 is mainly expressed in the lamina joint during leaf development, and particularly, is induced by the phytohormones abscisic acid, gibberellic acid, auxin, and brassinosteroids. LC2 is localized in the nucleus and defects of LC2 result in altered expression of cell division and hormone-responsive genes, indicating an important role of LC2 in regulating leaf inclination and mediating hormone effects. 展开更多
关键词 leaf inclination RICE VIN3-1ike protein cell division LC2
下载PDF
An efficient algorithm to compute transient pressure responses of slanted wells with arbitrary inclination in reservoirs 被引量:3
18
作者 Wang Haitao Zhang Liehui +2 位作者 Guo Jingjing Liu Qiguo He Xinming 《Petroleum Science》 SCIE CAS CSCD 2012年第2期212-222,共11页
Compared with vertical and horizontal wells, the solution and computation of transient pressure responses of slanted wells are more complex. Vertical and horizontal wells are both simplified cases of slanted wells at ... Compared with vertical and horizontal wells, the solution and computation of transient pressure responses of slanted wells are more complex. Vertical and horizontal wells are both simplified cases of slanted wells at particular inclination, so the model for slanted wells is more general and more complex than other models for vertical and horizontal wells. Many authors have studied unsteady-state flow of fluids in slanted wells and various solutions have been proposed. However, until now, few of the published results pertain to the computational efficiency. Whether in the time domain or in the Laplace domain, the computation of integration of complex functions is necessary in obtaining pressure responses of slanted wells, while the computation of the integration is complex and time-consuming. To obtain a perfect type curve the computation time is unacceptable even with an aid of high-speed computers. The purpose of this paper is to present an efficient algorithm to compute transient pressure distributions caused by slanted wells in reservoirs. Based on rigorous derivation, the transient pressure solution for slanted wells of any inclination angle is presented. Assuming an infinite-conductivity wellbore, the location of the equivalent-pressure point is determined. More importantly, according to the characteristics of the integrand in a transient pressure solution for slanted wells, the whole integral interval is partitioned into several small integral intervals, and then the method of variable substitution and the variable step-size piecewise numerical integration are employed. The amount of computation is significantly reduced and the computational efficiency is greatly improved. The algorithm proposed in this paper thoroughly solved the difficulty in the efficient and high-speed computation of transient pressure distribution of slanted wells with any inclination angle. 展开更多
关键词 Arbitrary inclination slanted well transient pressure behavior efficient algorithm variable step-size piecewise integration
下载PDF
Simulation of Canopy Leaf Inclination Angle in Rice 被引量:1
19
作者 ZHANG Xiao-cui LU Chuan-gen +3 位作者 HU Ning YAO Ke-min ZHANG Qi-jun DAI Qi-gen 《Rice science》 SCIE 2013年第6期434-441,共8页
A leaf inclination angle distribution model, which is applicable to simulate leaf inclination angle distribution in six heights of layered canopy at different growth stages, was established by component factors affect... A leaf inclination angle distribution model, which is applicable to simulate leaf inclination angle distribution in six heights of layered canopy at different growth stages, was established by component factors affecting plant type in rice. The accuracy of the simulation results was validated by measured values from a field experiment. The coefficient of determination (R2) and the root mean square error (RMSE) between the simulated and measured values were 0.9472 and 3.93%, respectively. The simulation results showed that the distribution of leaf inclination angles differed among the three plant types. The leaf inclination angles were larger in the compact variety Liangyoupeijiu with erect leaves than in the loose variety Shanyou 63 with droopy leaves and the intermediate variety Liangyou Y06. The leaf inclination angles were distributed in the lower range in Shanyou 63, which matched up with field measurements. The distribution of leaf inclination angles in the same variety changed throughout the seven growth stages. The leaf inclination angles enlarged gradually from transplanting to booting. During the post-booting period, the leaf inclination angle increased in Shanyou 63 and Liangyou Y06, but changed little in Liangyoupeijiu. At every growth stage of each variety, canopy leaf inclination angle distribution on the six heights of canopy layers was variable. As canopy height increased, the layered leaf area index (LAI) decreased in all the three plant types. However, while the leaf inclination angles showed little change in Liangyoupeijiu, they became larger in Shanyou 63 but smaller in Liangyou Y06. The simulation results used in the constructed model were very similar to the actual measurement values. The model provides a method for estimating canopy leaf inclination angle distribution in rice production. 展开更多
关键词 RICE leaf inclination angle SIMULATION plant type CANOPY
下载PDF
Effect of the Inclination Angle on Slippage Loss in Gas-Liquid Two-Phase Flow 被引量:4
20
作者 Yushan Liu Yubin Su +2 位作者 Zhenhua Wu Wei Luo Ruiquan Liao 《Fluid Dynamics & Materials Processing》 EI 2020年第3期475-488,共14页
The lifting efficiency and stability of gas lift well are affected by the socalled slippage-loss effect in gas-liquid two-phase flow.The existing studies on this subject have generally been based on vertical and horiz... The lifting efficiency and stability of gas lift well are affected by the socalled slippage-loss effect in gas-liquid two-phase flow.The existing studies on this subject have generally been based on vertical and horizontal wells.Only a few of them have considered inclined pipes.In the present work a new focused study is presented along these lines.More specifically,we use the non-slip pressure drop model with Flanigan’s fluctuation correction coefficient formula(together with the parameters of slippage density,slippage pressure drop and slippage ratio)to analyze the influence of the inclination angle on slippage loss for different conditions(different gas-liquid superficial velocity and pipe diameters).Moreover,the“standard regression coefficient method”is used for multi-factor sensitivity analysis.The experimental results indicate that slippage loss is affected by multiple factors,and the influence of the inclination angle on slippage loss is less significant than other factors.The change of the slippage pressure drop with the superficial velocity of gas-liquid is similar to that of the total pressure drop.The inclination angles of 45°and 60°have the greatest influence on slippage loss.The correlation between slippage density and slippage ratio is not obvious.Using the so-called slippage ratio seems to be a more accurate option to evaluate the degree of slippage loss. 展开更多
关键词 inclined pipes gas-liquid flow slippage loss pressure drop gas-liquid ratio
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部