期刊文献+
任意字段
题名或关键词
题名
关键词
摘要
作者
第一作者
机构
刊名
分类号
参考文献
作者简介
基金资助
栏目信息
共找到6,521篇文章
< 1 2 … 250 >
每页显示 20 50 100
已选0条
引用分析
参考文献
引证文献
 统计分析
检索结果
已选文献
显示方式：
Nonlinear mechanical behavior and shell-joint modeling method in rectangular pipe-jacking tunnel joints 认领 引用
1
作者 Zhengdong HUANG Youjun XU +3 位作者 Pengfei LI Chao ZHANG Yuhan SHAN Xu ZHANG 《ENGINEERING Structure and Civil Engineering》 SCIE EI CAS CSCD 2026年第4期804-827,共24页
Rectangular pipe-jacking tunnels are highly prone to longitudinal deformation under the influence of adjacent engineering activities,uneven foundation settlement,and changes in surface loads.These problems may lead to... Rectangular pipe-jacking tunnels are highly prone to longitudinal deformation under the influence of adjacent engineering activities,uneven foundation settlement,and changes in surface loads.These problems may lead to structural damage at the joints of rectangular pipe-jacking tunnels,potentially triggering engineering disasters.In response to these situations,this paper experimentally studies the effects of different foundation conditions and steel sleeve ring design parameters on their shear stiffness and rotational stiffness.It reveals three stages of joint failure:gap closure,steel sleeve ring stress,and deformation failure.A three-dimensional refined numerical simulation method is adopted to study the deformation and failure characteristics of joints under different foundation strengths and steel sleeve ring design parameters,analyze the mechanical performance of the joints of rectangular pipe-jacking tunnels,and verify the reliability of the experimental results.Based on the experimental and numerical simulation results,considering the nonlinear characteristics of the joints of rectangular pipe-jacking tunnels,a shell-joint theoretical model is constructed.Precise simulation is achieved through the combination of‘rotation+shear’dynamic elements,and the stiffness matrix at the joints and the calculation method of mechanical elements are derived.The shell-joint theoretical model is used to compare and verify the results of the joint tests of rectangular pipe-jacking tunnels,confirming the accuracy and practicality of the shell-joint theoretical model. 展开更多
关键词 rectangular pipe-jacking shell-joint mechanical model foundation stiffness longitudinal deformation
暂未订购 下载PDF
Gradient Descent-Based Prediction of Heat-Transmission Rate of Engine Oil-Based Hybrid Nanofluid over Trapezoidal and Rectangular Fins for Sustainable Energy Systems 认领 引用
2
作者 Maddina Dinesh Kumar S.U.Mamatha +2 位作者 Khalid Masood Nehad Ali Shah Se-Jin Yook 《Computer Modeling in Engineering & Sciences》 SCIE EI 2026年第1期627-660,共34页
Fluid dynamic research on rectangular and trapezoidal fins is aimed at increasing heat transfer by means of large surfaces.The trapezoidal cavity form is compared with its thermal and flow performance,and it is reveal... Fluid dynamic research on rectangular and trapezoidal fins is aimed at increasing heat transfer by means of large surfaces.The trapezoidal cavity form is compared with its thermal and flow performance,and it is revealed that trapezoidal fins tend to be more efficient,particularly when material optimization is critical.Motivated by the increasing need for sustainable energy management,this work analyses the thermal performance of inclined trapezoidal and rectangular porous fins utilising a unique hybrid nanofluid.The effectiveness of nanoparticles in a working fluid is primarily determined by their thermophysical properties;hence,optimising these properties can significantly improve overall performance.This study considers the dispersion of Graphene Oxide(GO)and Molybdenum Disulfide in the base fluid,engine oil.Temperature profiles are analysed by altering the radiative,porosity,wet porous,and angle of inclination parameters.Surface and contour plots are constructed by using the Lobatto IIIa Collocation Method with BVP5C solver in MATLAB and Gradient Descent Optimisation to predict the combined heat transfer rate.According to the study,fluid temperature consistently decreases when the angle of inclination,wet porous parameter,porosity parameter,and radiative parameter increase,suggesting significantly improved heat dissipation.The trapezoidal fin consistently exhibits a superior heat transfer mechanism than a rectangular fin.It is found that the trapezoidal fin transmits heat at a rate that is 0.05%higher than that of the rectangular fin.Validation of the present study is done through the comparison of previous studies.This research provides useful design insights for sophisticated engineering uses,including electrical cooling devices,heat exchangers,radiators,and solar heaters. 展开更多
关键词 Rectangular fin hybrid nanofluid trapezoidal fin angle of inclination gradient descent optimization Lobatto IIIa collocation method
暂未订购 下载PDF
Numerical Investigation of Fluid Energy Evolution Under the Wave-Induced Gap Resonance Between Stationary Floating Rectangular Structures 认领 引用
3
作者 YU An-liang WANG Xin-yu +3 位作者 Domenico Davide MERINGOLO LIU Yong GONG Shao-dong WU Guo-xiang 《China Ocean Engineering》 SCIE EI CSCD 2026年第3期576-589,共14页
This study quantitatively examined the fluid energy evolution and dissipation process near narrow gaps formed between multiple floating rectangular structures under wave-induced gap resonance conditions.Given the limi... This study quantitatively examined the fluid energy evolution and dissipation process near narrow gaps formed between multiple floating rectangular structures under wave-induced gap resonance conditions.Given the limited understanding of gap resonance mechanisms through fluid energy analysis,a numerical wave flume based on theδ-LES-Smoothed Particle Hydrodynamics(SPH)approach was developed to investigate how incident wave and structural parameters influence the temporal evolution of fluid energy components.The findings reveal that for two floating boxes,the fluid energy dissipation within one wave period in the gap region between the boxes constitutes 81%of the total fluid energy dissipation in the fluid domain.This proportion remains consistent across varying incident wave heights under gap resonance conditions.The temporal distribution of fluid energy dissipation rate shows two peak values within one wave period,exhibiting significant waveform asymmetry.Additionally,in three-box configurations,the two narrow gap regions serve as primary zones of fluid energy dissipation,with energy dissipation patterns closely resembling those observed in the single gap region.Through comprehensive analysis of fluid energy evolution,this research advances the fundamental understanding of gap resonance mechanisms. 展开更多
关键词 multiple floating rectangular structures SPH method gap resonance wave energy evolution
暂未订购 下载PDF
Experimental and Numerical Evaluation of Elevated Rectangular Water Tank Frequencies Using Digital Image Correlation 认领 引用
4
作者 Askr M N Eraky A +1 位作者 Salama A Emad S 《Journal of Harbin Institute of Technology(New Series)》 CAS 2026年第2期56-67,共12页
Elevated,rectangular water tanks are an essential component of the water supply network and for emergency water storage.However,determining the dynamic response from seismic loads will require accurate estimates of th... Elevated,rectangular water tanks are an essential component of the water supply network and for emergency water storage.However,determining the dynamic response from seismic loads will require accurate estimates of their natural frequencies to help avoid damage or failure.Several numerical and analytical methodologies depend on assumptions that may not account for the complexity of fluid-structure interaction regarding rectangular geometries,indicating a strong need for solid experimental validation.This study pioneers the application of Digital Image Correlation(DIC),a non-contact optical technique,to measure the natural frequencies of a small-scale acrylic and Teflon tank,addressing this gap with a novel experimental approach.The method includes DIC using a high-speed camera,image analyzed by MATLAB,frequency analysis by Continuous Wavelet Transformation(CWT),and Fast Fourier Transformation(FFT);ANSYS finite element analysis,simplified models based on Eurocode and the Egyptian Code of Practice(ECP).Study results indicate that DIC is critical for attaining high accuracy,with maximum error differing by 2.92% for impulsive and 4.55%for convective frequencies from ANSYS and provides a better measure of dynamic response compared to contact-based measurements.Impulsive frequency decreased from 5.8724 Hz to 4.0085 Hz,and sloshing increased from 1.00 Hz to 1.84 Hz,as the water cover height varied from 0 cm to 9.8 cm.The Eurocode and ECP models describe acceptable errors of 7.36% and 9.21%,respectively.DIC showed higher accuracy,making it a useful tool for seismic design.This study improves the safety and reliability of designs for elevated water tanks in seismic regions with elevated seismic risk. 展开更多
关键词 fluid-structure interaction natural frequency rectangular tank elevated tank sloshing waves DIC
暂未订购 下载PDF
Analytical solutions of vertical load on deep rectangular jacked pipe considering tunnelling-induced ground loss 认领 引用 被引量：3
5
作者 LI Jian-ye FANG Qian +4 位作者 LIU Xiang WANG Gan HUANG Jun DU Jian-ming ZHANG Zi-yi 《Journal of Central South University》 SCIE EI CAS CSCD 2025年第5期1855-1872,共18页
Determining earth pressure on jacked pipes is essential for ensuring lining safety and calculating jacking force,especially for deep-buried pipes.To better reflect the soil arching effect resulting from the excavation... Determining earth pressure on jacked pipes is essential for ensuring lining safety and calculating jacking force,especially for deep-buried pipes.To better reflect the soil arching effect resulting from the excavation of rectangular jacked pipes and the distribution of the earth pressure on jacked pipes,we present an analytical solution for predicting the vertical earth pressure on deep-buried rectangular pipe jacking tunnels,incorporating the tunnelling-induced ground loss distribution.Our proposed analytical model consists of the upper multi-layer parabolic soil arch and the lower friction arch.The key parameters(i.e.,width and height of friction arch B and height of parabolic soil arch H 1)are determined according to the existing research,and an analytical solution for K l is derived based on the distribution characteristics of the principal stress rotation angle.With consideration for the transition effect of the mechanical characteristics of the parabolic arch zone,an analytical solution for soil load transfer is derived.The prediction results of our analytical solution are compared with tests and simulation results to validate the effectiveness of the proposed analytical solution.Finally,the effects of different parameters on the soil pressure are discussed. 展开更多
关键词 rectangular pipe jacking tunnel vertical load multi-layer parabolic soil arch model soil arching
暂未订购 下载PDF
Study on the effect of shape parameters and initiation points of rectangular high explosive on the spatial distribution of blast loads 认领 引用 被引量：2
6
作者 Longkui Chen Hongyu Zhao +2 位作者 Yongliang Zhang Shenghong Huang Chunhai Li 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2025年第3期102-120,共19页
Rectangular explosive charges are usually used in military or civilian explosive transportation and storage.The effects of shape parameters and detonation positions on the peak overpressure and maximum impulse of blas... Rectangular explosive charges are usually used in military or civilian explosive transportation and storage.The effects of shape parameters and detonation positions on the peak overpressure and maximum impulse of blasts lack comprehensive investigation,which is significant for the design of blast-resistant structures.In this paper,the side-length ratio of the rectangle,orientation,and detonation position of the charge are chosen as controlling parameters to investigate their influence on blast loads in the scaled distances of the gauges ranging from 0.63 to 10.54 m/kg1/3 with well validated 3D numerical simulations.The results show that there is a large difference in the near-field spatial distribution of the blast load of the rectangular charge;if the blast load of the rectangular charge is simply evaluated with the spherical charge,the maximum peak overpressure(maximum impulse)will be underestimated by a factor of 7.46(4.84).This must be taken seriously by blast-resistant structure designers.With the increase in the scaled distance,when the critical scaled distance is greater than 6.32(7.38)m/kg1/3,the influence of the charge shape on the maximum peak overpressure(maximum impulse)of the spatial blast load can be ignored.In general,the impact of detonation of the charge at the end on the maximum peak overpressure is greater compared with central detonation,but for the impact of the maximum impulse,it is necessary to pay attention to the side-length ratio of the rectangular charge and the specific detonation position on the end face.Furthermore,the structural response of steel plates placed at different azimuths under the blast load of a rectangular charge is preliminarily analyzed,and the results show that the deformation and energy of the plates are consistent with the distribution of the blast load.These analysis results provide a reference for the explosion protection design in near-field air explosions. 展开更多
关键词 Rectangular charge Side-length ratio Detonation Bridge wave Spherical equivalence
暂未订购 下载PDF
Failure mechanism and damage constitutive model of rectangular tunnels under water-rich condition 认领 引用
7
作者 Banquan Zeng Jianhang Chen +5 位作者 Wuyan Xu Xiaoyong An Shiji Wang Songsong Hu Kun Wang Yu Chen 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2025年第12期2245-2264,共20页
To investigate groundwater influence on stability and rockburst mechanism of deep hard-rock rectangular tunnels,water-immersed treatment and uniaxial compressive acoustic emission(AE)experiments were conducted on rect... To investigate groundwater influence on stability and rockburst mechanism of deep hard-rock rectangular tunnels,water-immersed treatment and uniaxial compressive acoustic emission(AE)experiments were conducted on rectangular tunnel specimens.Energy dissipation characteristics,AE evolution characteristics and damage evolution characteristics of rectangular tunnels were analysed under waterimmersed condition.Under water-immersed condition,tunnel specimens were quite sensitive to water.Average peak stress and average peak strain energy exhibited negative exponential decay with waterimmersed time.Among them,after 12 d of water immersion,average peak stress of specimens decreased by 28%.Average total strain energy decreased by 70%.Average elastic strain energy decreased by 71%and average dissipated strain energy decreased by 68%.After 62 d of water immersion,average peak stress of specimens decreased by 34%.Average total strain energy decreased by 78%.Average elastic strain energy decreased by 79%and average dissipated strain energy decreased by 75%.Water weakened bonding among mineral particles.Moreover,it undermined load-bearing capacity and diminished energystorage properties.Under high stress,massive releasable elastic strain energy stored in natural specimens within pre-peak stage may abruptly release after peak stress.This caused rapid crack development and connection in specimens.During accumulation and release of elastic strain energy,initial failure typically occurred at sidewalls.This failure location was not affected by water.Compared with natural specimens,Specimens immersed in water for 62 d had the lowest peak values of cumulative amplitude,cumulative AE energy and cumulative AE count.After 62 d of water immersion,peak values of cumulative amplitude,cumulative AE energy and cumulative AE count of specimens decreased by 84%,97%and 99%.Compared with AE damage model,fitting degree of energy damage model was higher.For natural specimens,fitting degree of energy damage model was 0.96.For specimens immersed in water for 12 d,fitting degree of energy damage model was 0.96.For specimens immersed in water for 62 d,fitting degree of energy damage model was 0.72.Therefore,an energy damage model had more remarkable applicability and reliability.By establishing dynamic mapping relationship between energy and damage in the model,accuracy of rockburst early warning has been significantly improved.This provided scientific basis for support structure design of rectangular tunnels and regulation of high strain energy. 展开更多
关键词 Rectangular tunnels Energy dissipation characteristics Evolution characteristics of AE signals Damage evolution characteristics Energy damage model
暂未订购 下载PDF
Flexural Nonlinear Natural Frequency Analysis of Rotational Functionally Graded Sandwich Rectangular Plates with Uniform and Inhomogeneous Pore Distributions in Thermal Environments 认领 引用
8
作者 Dazhi Zhang Yongqiang Li 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2025年第4期664-676,共13页
This study investigates the nonlinear dynamic properties of rotating functionally graded sandwich rectangular plates in a thermal environment.The nonlinear vibration equations for a rotating metal-ceramic functionally... This study investigates the nonlinear dynamic properties of rotating functionally graded sandwich rectangular plates in a thermal environment.The nonlinear vibration equations for a rotating metal-ceramic functionally graded sandwich rectangular plate in a thermal environment are derived using classical thin plate theory and Hamilton’s principle,considering geometric nonlinearity,temperature-dependent material properties,and power law distribution of components through the thickness.With cantilever boundary conditions,the flexural nonlinear differential equations of the rectangular sandwich plate are obtained via the Galerkin method.Since the natural vibration differential equations exhibit nonlinear characteristics,the multiscale method is employed to derive the expression for nonlinear natural frequency.An example analysis reveals how the natural frequency of a functionally graded sandwich rectangular plate varies with rotational speed and temperature.Results show that the nonlinear/linear frequency ratio increases with rotational angular velocity Ω and thickness-to-length ratio h/a,follows a cosine-like periodic pattern with the setting angle,and shows a sharp decrease followed by a rapid increase with increasing width-to-length ratio b/a.The derived analytical solutions for nonlinear frequency provide valuable insights for assessing the dynamic characteristics of functionally graded structures. 展开更多
关键词 Rectangular plate Sandwich Functionally graded material Nonlinear natural frequency Rotational motion
暂未订购 下载PDF
Experimental and Numerical Study on Flow and Heat Transfer Characteristics in Rectangular Channels with Leaf-Shaped Pin Fins 认领 引用 被引量：1
9
作者 Chao Zhang Runze Yan +2 位作者 Honghui Li Qingheng Tang Qinghai Zhao 《Frontiers in Heat and Mass Transfer》 EI CAS 2025年第2期421-440,共20页
The growing need for enhanced heat dissipation is compelling the development of more effective heat exchangers.Innovation inspired by nature bionics,four types of leaf-shaped pin fins were proposed and four combinatio... The growing need for enhanced heat dissipation is compelling the development of more effective heat exchangers.Innovation inspired by nature bionics,four types of leaf-shaped pin fins were proposed and four combinations of them were considered.The leaf-shaped design of the cooling pin fin enhances uniformity and synergy,effectively creating an optimized flow path that boosts cooling performance.Eight three-dimensional conjugate heat transfer models in staggered arrangement were developed using ANSYS-Fluent software.Aluminum6061material was used as the heat sinkmaterial and single-phase liquid water flowed through the rectangular channel where the Reynolds(Re)number varies from 40 to 100.Using the same boundary conditions as the software simulations,two leaf-shaped channels were printed to validate numerical models.Velocity field and temperature differences of the eight proposed leaf-shaped pin fins configurations were discussed by comparison with cylindrical pin fins.Based on the findings of this study,at a Reynolds number of 80,the Leaf B Staggered Array(LBSA)records a maximum temperature that is 0.72 K lower than that of the cylindrical pin fins arrangement.Additionally,the LBSA exhibits a reduction in the friction factor by approximately 33.3%relative to the circular pin fins array under the same Re.This implies that the design of LBSA has been optimized to provide better heat dissipation performance while maintaining lower energy consumption.Furthermore,the LBSA demonstrates the most favorable thermal-hydraulic performance index(TPI),which is 1.18 times higher than that of the circular pin fins arrangement at Re=80.The temperature reduction and friction factor reduction of the lobed channel is more pronounced than that of the conventional cooling channel,highlighting its potential to increase heat transfer efficiency and reduce energy consumption in practical applications. 展开更多
关键词 Heat transfer enhancement leaf-shaped pin fins rectangular channel single-phase heat transfer staggered arrangement
暂未订购 下载PDF
Thermo-Hydraulic Performances of Microchannel Heat Sinks with Different Types of Perforated Rectangular Blocks 认领 引用
10
作者 Heng Zhao Honghua Ma +4 位作者 Hui Liu Xiang Yan Huaqing Yu Yongjun Xiao Xiao Xiao 《Fluid Dynamics & Materials Processing》 EI 2025年第1期87-105,共19页
The behavior of single-phase flow and conjugate heat transfer in micro-channel heat sinks(MCHS)subjected to auniform heat flux is investigated by means of numerical simulations.Various geometrical configurations areex... The behavior of single-phase flow and conjugate heat transfer in micro-channel heat sinks(MCHS)subjected to auniform heat flux is investigated by means of numerical simulations.Various geometrical configurations areexamined,particularly,the combinations of rectangular solid and perforated blocks,used to create a disturbancein the flow.The analysis focuses on several key aspects and related metrics,including the temperature distribution,the mean Fanning friction factor,the pressure drop,the Nusselt number,and the overall heat transfer coefficientacross a range of Reynolds numbers(80–870).It is shown that the introduction of such blocks significantlyenhances the heat transfer performances of the MCHS compared to the straight-through flow channel.Specifically,a case is found where the Nusselt number increases by 2.3 times relative to the reference case.The integrationof perforated blocks facilitates the generation of vorticity within the channel,promoting the mixing of coldand hot fluids.Notably,MCHS incorporating perforated rectangular blocks exhibit more pronounced heat transferbenefits at Reynolds numbers smaller than 400. 展开更多
关键词 Micro-channel heat sink(MCHS) perforated rectangular blocks thermal performance convection heat transfer
暂未订购 下载PDF
Optimization of a Dual-Baffled Rectangular Tank Against the Sloshing Phenomenon 认领 引用 被引量：2
11
作者 Hassan Saghi Dezhi Ning +1 位作者 Shunqi Pan Reza Saghi 《Journal of Marine Science and Application》 CSCD 2022年第1期116-127,共12页
A dual-baffled rectangular tank with different configurations is proposed to reduce the sloshing effect,and design optimization is conducted through numerical simulations with open-source software,namely OpenFOAM,base... A dual-baffled rectangular tank with different configurations is proposed to reduce the sloshing effect,and design optimization is conducted through numerical simulations with open-source software,namely OpenFOAM,based on the computational fluid dynamic model.A series of physical experiments in the dual-baffled rectangular tank is performed for model validation and design optimization with the measured water surface elevation distributions along the tank.The optimization uses the calculated maximum horizontal force exerted on the tank and entropy generation(EG)as the criterion.Results show that the dual-baffle configuration positioned at the tank center is more effective in reducing the sloshing than that of the single baffle when the relative baffle height and initial water depth ratio(Hb/Hw,where Hb and Hw represent baffle height and static water depth,respectively)are larger than 0.5.However,such an effect then diminishes when the ratio is larger than 0.75.The effect of the dual-baffle configuration on the sway motion under the condition of different motion amplitudes and frequencies is also evaluated.The results show that the reduction in the maximum horizontal force is almost the same for dual-and single-baffled configurations and reaches the minimum when the sway motion amplitude is near 0.03 m.The dual-baffled configuration for the angular frequency of the sway motion is more effective than the single-baffled in reducing the sloshing at the low angular frequencies but is only less effective at high angular frequencies.Furthermore,the optimal baffle inclination angle is 85°when the inclined straight and curved baffles are used,and curved baffles can successfully decrease the horizontal force exerted on the tank and EG. 展开更多
关键词 Rectangular storage tank Dual-baffled rectangular tank Sloshing phenomenon Optimization Horizontal force Entropy generation
暂未订购 下载PDF
THE METHOD OF THE RECIPROCAL THEOREM OF FORCED VIBRATION FOR THE ELASTIC THIN RECTANGULAR PLATES(Ⅰ)—RECTANGULAR PLATES WITH FOUR CLAMPED EDGES AND WITH THREE CLAMPED EDGES 认领 引用 被引量：2
12
作者 付宝连 李农 《Applied Mathematics and Mechanics(English Edition)》 SCIE 1989年第8期727-749,共23页
In this paper the method of the reciprocal theorem (MRT) is extended to solve the steady state responses of rectangular plater under harmonic disturbing forces. A series of the closed solutions of rectangular plates w... In this paper the method of the reciprocal theorem (MRT) is extended to solve the steady state responses of rectangular plater under harmonic disturbing forces. A series of the closed solutions of rectangular plates with various boundary conditions are given and the tables and figures which have practical value are provided.MRT is a simple, convenient and general method for solving the steady stale responses of rectangular plates under various harmonic disturbing forces.The paper contains three parts: (I) rectangular plates with four damped edges and with three clamped edges; (II) rectangular plates with two adjacent clamped edges; (III) cantilever plates.We arc going to publish them one after another. 展开更多
关键词 RECTANGULAR PLATES WITH FOUR CLAMPED EDGES AND WITH THREE CLAMPED EDGES THE METHOD OF THE RECIPROCAL THEOREM OF FORCED VIBRATION FOR THE ELASTIC THIN RECTANGULAR PLATES
暂未订购 下载PDF
Effects of Perforated Baffle on Reducing Sloshing in Rectangular Tank:Experimental and Numerical Study 认领 引用 被引量：17
13
作者 薛米安 林鹏智 +3 位作者 郑金海 马玉祥 苑晓丽 Viet-Thanh NGUYENa 《China Ocean Engineering》 SCIE EI CSCD 2013年第5期615-628,共14页
A liquid sloshing experimental rig driven by a wave-maker is designed and built to study liquid sloshing problems in a rectangular liquid tank with perforated baffle. A series of experiments are conducted in this expe... A liquid sloshing experimental rig driven by a wave-maker is designed and built to study liquid sloshing problems in a rectangular liquid tank with perforated baffle. A series of experiments are conducted in this experimental rig to estimate the free surface fluctuation and pressure distribution by changing external excitation frequency of the shaking table. An in-house CFD code is also used in this study to simulate the liquid sloshing in three-dimensional （3D） rectangular tank with perforated baffle. Good agreements of free surface elevation and pressure between the numerical results and the experimental data are obtained and presented. Spectral analysis of the time history of free surface elevation is conducted by using the fast Fourier transformation. 展开更多
关键词 liquid sloshing experimental study rectangular tank perforated baffle
暂未订购 下载PDF
Shape ratio effects on the mechanical characteristics of rectangular prism rocks and isolated pillars under uniaxial compression 认领 引用 被引量：15
14
作者 Kun Du Xuefeng Li +4 位作者 Rui Su Ming Tao Shizhan Lv Jia Luo Jian Zhou 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2022年第2期347-362,共16页
Isolated pillars in underground mines are subjected to uniaxial stress,and the load bearing cross-section of pillars is commonly rectangularly shaped.In addition,the uniaxial compression test(UCT)is widely used for de... Isolated pillars in underground mines are subjected to uniaxial stress,and the load bearing cross-section of pillars is commonly rectangularly shaped.In addition,the uniaxial compression test(UCT)is widely used for determining the basic mechanical properties of rocks and revealing the mechanism of isolated pillar disasters under unidimensional stress.The shape effects of rock mechanical properties under uniaxial compression are mainly quantitatively reflected in the specific shape ratios of rocks.Therefore,it is necessary to study the detailed shape ratio effects on the mechanical properties of rectangular prism rock specimens and isolated pillars under uniaxial compressive stress.In this study,granite,marble and sandstone rectangular prism specimens with various height to width ratios(r)and width to thickness ratios(u)were prepared and tested.The study results show that r and u have a great influence on the bearing ability of rocks,and thin or high rocks have lower uniaxial compressive strength.Reducing the level of r can enhance the u effect on the strength of rocks,and increasing the level of u can enhance the r effect on the strength of rocks.The lateral strain on the thickness side of the rock specimen is larger than that on the width side,which implies that crack growth occurs easily on the thickness side.Considering r and u,a novel strength prediction model of isolated pillars was proposed based on the testing results,and the prediction model was used for the safety assessment of 179 isolated pillars in the Xianglu Mountain Tungsten Mine. 展开更多
关键词 Uniaxial compression test Isolated pillar Rectangular prism Shape ratio effect Failure property
暂未订购 下载PDF
Measurement and Correlation of Pressure Drop for Gas-Liquid Two-phase Flow in Rectangular Microchannels 认领 引用 被引量：16
15
作者 MA Youguang JI Xiyan +2 位作者 WANG Dongji FU Taotao ZHU Chunying 《Chinese Journal of Chemical Engineering》 SCIE EI CAS 2010年第6期940-947,共8页
The pressure drop of gas-liquid two-phase flow in microchannel is of fundamental importance in heat and mass transfer processes.In this work,the pressure drop of gas-liquid two-phase flow in horizontal rectangular cro... The pressure drop of gas-liquid two-phase flow in microchannel is of fundamental importance in heat and mass transfer processes.In this work,the pressure drop of gas-liquid two-phase flow in horizontal rectangular cross-section microchannels was measured by a pressure differential transducer system.Water,ethanol and n-propanol were used as liquid phase to study the effects of capillary number on pressure drop;air was used as the gas phase.Four microchannels with various dimensions of 100μm×200μm,100μm×400μm,100μm×800μm and 100μm×2000μm(depth×width)were used for determining the influence of configuration on the pressure drop.Experimental results showed that in micro-scale,the capillary number also affected the pressure drop remarkably,and in spite of only one-fold difference in aspect ratio,the variation of pressure drop reached up to near three times under the same experimental conditions.Taking the effects of aspect ratio and surface tension into account,a modi-fied correlation for Chisholm parameter C in the Chisholm model was proposed for predicting the frictional multi-plier,and the predicted values by the proposed correlation showed a satisfactory agreement with experimental data. 展开更多
关键词 pressure drop rectangular cross-section microchannel surface tension configuration influence Chis-holm parameter C
暂未订购 下载PDF
Tuning of band gaps for a two-dimensional piezoelectric phononic crystal with a rectangular lattice 认领 引用 被引量：9
16
作者 Yize Wang Fengming Li +2 位作者 Yuesheng Wang Kikuo Kishimoto Wenhu Huang 《Acta Mechanica Sinica》 SCIE EI CAS 2009年第1期65-71,共7页
In this paper, the elastic wave propagation in a two-dimensional piezoelectric phononic crystal is studied by considering the mechanic-electric coupling. The generalized eigenvalue equation is obtained by the relation... In this paper, the elastic wave propagation in a two-dimensional piezoelectric phononic crystal is studied by considering the mechanic-electric coupling. The generalized eigenvalue equation is obtained by the relation of the mechanic and electric fields as well as the Bloch-Floquet theorem. The band structures of both the in-plane and anti-plane modes are calculated for a rectangular lattice by the planewave expansion method. The effects of the lattice constant ratio and the piezoelectricity with different filling fractions are analyzed. The results show that the largest gap width is not always obtained for a square lattice. In some situations, a rectangular lattice may generate larger gaps. The band gap characteristics are influenced obviously by the piezoelectricity with the larger lattice constant ratios and the filling fractions. 展开更多
关键词 Piezoelectricity Phononic crystal Rectangular lattice - Plane-wave expansion method Band gap
暂未订购 下载PDF
Study on Failure Mechanism and Bearing Capacity of Three-Dimensional Rectangular Footing Subjected to Combined Loading 认领 引用 被引量：9
17
作者 张其一 栾茂田 王忠涛 《China Ocean Engineering》 SCIE EI 2008年第2期313-330,共18页
This paper presents two kinematic failure mechanisms of threc-dimensional rectangular footing resting on homogeneous undrained clay foundation under uniaxial vertical loading and uniaxial moment loading. The failure m... This paper presents two kinematic failure mechanisms of threc-dimensional rectangular footing resting on homogeneous undrained clay foundation under uniaxial vertical loading and uniaxial moment loading. The failure mechanism under vertical loading comprises a plane strain Prandti-type mechanism over the central part of the longer side, and the size of the mechanism gradually reduces at the ends of the longer side and over the shorter side as the corner of rectangular footing is being approached where the direction of soil motion remains normal to each corresponding side respectively. The failure mechanism under moment loading comprises a plane strain scoop sliding mechanism over the central part of the longer side, and the radius of scoop sliding mechanism increases linearly at the ends of the longer side. On the basis of the kinematic failure mechanisms mentioned above, the vertical ultimate bearing capacity and the ultimate bearing capacity against moment or moment ultimate bearing capacity are obtained by use of upper bound limit analysis theory. At the same time, numerical analysis results, Skempton＇ s results and Salgado et al. ＇s results are compared with this upper bound solution. It shows that the presented failure mechanisms and plastic limit analysis predictions are validated. In order to investigate the behaviors of undrained clay foundation beneath the rectangular footing subjected to the combined loadings, numerical analysis is adopted by virtue of the general-purpose FEM software ABAQUS, where the clay is assumed to obey the Mohr-Coulomb yielding criterion. The failure envelope and the ultimate bearing capacity are achieved by the numerical analysis results with the varying aspect ratios from length L to breadth B of the rectangular footing. The failure mechanisms of rectangular footing which are subjected to the combined vertical loading V and horizontal loading H （Vertical loading V and moment loading M, and horizontal loading H and moment loading M respectively are observed in the finite element analysis. ） is explained by use of the upper bound plasticity limit analysis theory. Finally, the reason of eccentricity of failure envelope in H-M loading space is given in this study, which can not be explained by use of the traditional ＇ swipe test＇. 展开更多
关键词 rectangular footing upper bound limit analysis failure mechardsm failure envelope combined loading
暂未订购 下载PDF
Rectangular Section Control Technology for Silicon Steel Rolling 认领 引用 被引量：10
18
作者 Xiao-chen WANG Quan YANG You-zhao SUN 《Journal of Iron and Steel Research International》 SCIE CAS CSCD 2015年第3期185-191,共7页
Rectangular section control technology （RSCT） was introduced to achieve high-precision profile control during silicon steel rolling. The RSCT principle and method were designed, and the whole RSCT control strategy w... Rectangular section control technology （RSCT） was introduced to achieve high-precision profile control during silicon steel rolling. The RSCT principle and method were designed, and the whole RSCT control strategy was developed. Specifically, RSCT included roll contour design, roiling technology optimization, and control strategy development, aiming at both hot strip mills （HSMs） and cold strip mills （CSMs）. Firstly, through the high-performance variable crown （HVC） work roll optimization design in the upper-stream stands and the limited shifting technology for schedule-free rolling in the downstream stands of HSMs, a hot strip with a stable crown and limited wedge, ：local spot, and single wave was obtained, which was suitable for cold rolling. Secondly, an approximately rectangular section was obtained by edge varying contact （EVC） work roll contour design, edge-drop setting control, and. closed loop control in the upper-stream, stands of CSMs. Moreover, complex-mode flatness control was realized by coordinating multiple shape-control methods in the downstream stands of CSMs. In addition, the RSCT approach was applied in several silicon-steel production plants, where an outsicanding performance and remarkable economic benefits were observed. 展开更多
关键词 silicon steel rectangular section control technology hot rolling cold rolling edge drop
暂未订购 下载PDF
Cross-sectional distortion behaviors of thin-walled rectangular tube in rotary-draw bending process 认领 引用 被引量：13
19
作者 赵刚要 刘郁丽 +1 位作者 杨合 卢彩红 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS 2010年第3期484-489,共6页
The cross-sectional distortion usually appears during rotary-draw bending process of thin-walled rectangular tube with small bending radius.To study the cross-sectional distortion of the tube,a three-dimensional finit... The cross-sectional distortion usually appears during rotary-draw bending process of thin-walled rectangular tube with small bending radius.To study the cross-sectional distortion of the tube,a three-dimensional finite-element model of the process was developed based on ABAQUS/Explicit code and its reliability was validated by experiment.Then,the cross-sectional distortion behaviors of the tube were investigated.The results show that a zone of larger circumferential stress appears on the tube when bending angle reaches 30°.And in the larger circumferential stress zone,the sagging phenomenon is produced obviously.The maximum cross-sectional distortion is located in the larger circumferential stress zone and the angle between the plane of maximum cross-sectional distortion and the bending reference plane is about 50°.The position of the maximum cross-sectional distortion keeps almost unchanged with the variation of the clearances between dies and tube. 展开更多
关键词 thin-walled rectangular tube aluminum alloy 3A21 rotary-draw bending cross-sectional distortion die clearance
暂未订购 下载PDF
Optimization of Baffled Rectangular and Prismatic Storage Tank Against the Sloshing Phenomenon 认领 引用 被引量：10
20
作者 Hassan SAGHI NING De-zhi +1 位作者 CONG Pei-wen ZHAO Ming 《China Ocean Engineering》 SCIE EI CSCD 2020年第5期664-676,共13页
The fluid motion in partially filled tanks with internal baffles has wide engineering applications. The installation of baffles is expected to reduce the effect of sloshing as well as the consequent environmental dama... The fluid motion in partially filled tanks with internal baffles has wide engineering applications. The installation of baffles is expected to reduce the effect of sloshing as well as the consequent environmental damages. In the present study, a series of experimental tests are performed to investigate the sloshing phenomenon in a baffled rectangular storage tank. In addition, the sloshing phenomenon is also modeled by using Open Foam. Based on the experimental and numerical studies, optimization of the geometric parameters of the tank is performed based on some criteria such as tank area, entropy generation, and the horizontal force exerted on the tank area due to the sloshing phenomenon.The optimization is also carried out based on the entropy generation minimization analysis. It is noted that the optimum baffle height is in the range of h_b/h_w=0.5-0.75 in the present study(where h_b and h_w are the baffle height and water depth, respectively). Based on the results, the optimal design of the tank is achieved with R_A= 0.9-1.0(where R_A=L/W, L and W are the length and width of the tank, respectively). The results also show that the increase of h_b can lead to a decrease of the maximum pressure and horizontal force exerted on the tank. It is also noted that the horizontal force exerted on the tank firstly continues to increase as the sway motion amplitude increases.However, as the normalized motion amplitude parameter, a/L(The parameter a is the motion amplitude), exceeds0.067, the effect of motion amplitude on the force is not obvious. The same optimization is also performed in the multiple-variable-baffled tank and prismatic storage tank. 展开更多
关键词 baffled rectangular storage tank experimental tests sloshing phenomenon optimization entropy generation Open Foam
暂未订购 下载PDF
已选0条
引用分析
参考文献
引证文献
 统计分析
检索结果
已选文献
上一页 1 2 … 250 下一页 到第 页
在线咨询 使用帮助 返回顶部 意见反馈