资源类型

期刊论文 186

年份

2023 11

2022 18

2021 7

2020 14

2019 8

2018 9

2017 6

2016 9

2015 12

2014 9

2013 2

2012 11

2011 5

2010 14

2009 15

2008 8

2007 11

2006 2

2005 2

2004 2

展开 ︾

关键词

CFD 3

有限元 3

耦合 3

有限元法 2

CO 1

DSM(设计结构矩阵) 1

三星一线 1

两湖平原 1

事谐 1

互耦;多输入多输出;天线阵列;超表面;去耦 1

人和 1

住宅厨房 1

信息融合预警 1

倾斜镜;动态系统;输出输出耦合;物理建模;子空间辨识 1

偶联 1

催化剂工程 1

关系学习 1

关系耦合 1

内外因耦合 1

展开 ︾

检索范围:

排序: 展示方式:

Simulation of steel beam under ceiling jet based on a wind–fire–structure coupling model

《结构与土木工程前沿(英文)》 2023年 第17卷 第1期   页码 78-98 doi: 10.1007/s11709-022-0936-8

摘要: For localized fires, it is necessary to consider the thermal and mechanical responses of building elements subject to uneven heating under the influence of wind. In this paper, the thermomechanical phenomena experienced by a ceiling jet and I-beam in a structural fire were simulated. Instead of applying the concept of adiabatic surface temperature (AST) to achieve fluid–structure coupling, this paper proposes a new computational fluid dynamics–finite element method numerical simulation that combines wind, fire, thermal, and structural analyses. First, to analyze the velocity and temperature distributions, the results of the numerical model and experiment were compared in windless conditions, showing good agreement. Vortices were found in the local area formed by the upper and lower flanges of the I-beam and the web, generating a local high-temperature zone and enhancing the heat transfer of convection. In an incoming-flow scenario, the flame was blown askew significantly; the wall temperature was bimodally distributed in the axial direction. The first temperature peak was mainly caused by radiative heat transfer, while the second resulted from convective heat transfer. In terms of mechanical response, the yield strength degradation in the highest-temperature region in windless conditions was found to be significant, thus explaining the stress distribution of steel beams in the fire field. The mechanical response of the overall elements considering the incoming flows was essentially elastic.

关键词: CFD–FEM coupling     steel beam     wind     ceiling jet     numerical heat transfer    

大功率刮板输送机阀控充液型液力偶合器研发

李国平,赵美,赵继云,张德生

《中国工程科学》 2011年 第13卷 第11期   页码 39-49

摘要: 基于CFD方法优化设计了阀控偶合器腔型,采用单向流体—结构耦合(FSI)方法分析了泵轮强度,并对结构进行了优化,研制出高压外控型电液控制阀组,对无键连接轴超高压拆装、大型铜合金叶轮铸造等进行技术攻关

关键词: 刮板输送机     阀控偶合器     软启动     控制阀组     CFD    

Experimental and CFD analysis of nozzle position of subsonic ejector

Xilai ZHANG, Shiping JIN, Suyi HUANG, Guoqing TIAN

《能源前沿(英文)》 2009年 第3卷 第2期   页码 167-174 doi: 10.1007/s11708-009-0001-5

摘要: The influence of nozzle position on the performance of an ejector was analyzed qualitatively with free jet flow model. Experimental investigations and computational fluid dynamics (CFD) analysis of the nozzle position of the subsonic ejector were also conducted. The results show that there is an optimum nozzle position for the ejector. The ejecting coefficient reaches its maximum when the nozzle is positioned at the optimum and decreases when deviating. Moreover, the nozzle position of an ejector is not a fixed value, but is influenced greatly by the flow parameters. Considering the complexity of the ejector, CFD is reckoned as a useful tool in the design of ejectors.

关键词: ejector     nozzle position     ejecting coefficient     CFD    

Numerical evaluation of group-pile foundation subjected to cyclic horizontal load

Youngji JIN, Xiaohua BAO, Yoshimitsu KONDO, Feng ZHANG,

《结构与土木工程前沿(英文)》 2010年 第4卷 第2期   页码 196-207 doi: 10.1007/s11709-010-0021-6

摘要: In this paper, three-dimensional (3D) finite element analyses of a real-scale group-pile foundation subjected to horizontal cyclic loading are conducted using a program named DBLEAVES. In the simulations, nonlinear behaviors of ground and piles are described by subloading model and the axial-force dependent model (AFD model) which considered the axial-force dependency in the nonlinear moment-curvature relations. In order to consider the influence of an effective stress path on the prediction of the group-pile foundation, the analyses are conducted within the framework of the soil-water coupling method with finite-difference and finite-element regime. The material parameters of soils are determined based on conventional triaxial drained compression tests on undisturbed and remolded specimens. The applicability of the proposed numerical method is encouraging, and therefore, it is quite confident to say that the method can be used to predict the mechanical behaviors of group-pile foundation to a satisfactory accuracy, particularly with the effective stress analysis.

关键词: group-pile foundation     real-scale cyclic loading test     three-dimensional finite element method (3D-FEM)     soil-water coupling analysis     undisturbed and remolded specimens    

Two-scale modeling of granular materials: A FEM-FEM approach

Yun-Zhu CAI, Yu-Ching WU

《结构与土木工程前沿(英文)》 2013年 第7卷 第3期   页码 304-315 doi: 10.1007/s11709-013-0213-y

摘要: In the present paper, a homogenization-based two-scale FEM-FEM model is developed to simulate compactions of visco-plastic granular assemblies. The granular structure consisting of two-dimensional grains is modeled by the microscopic finite element method at the small-scale level, and the homogenized viscous assembly is analyzed by the macroscopic finite element method at large-scale level. The link between scales is made using a computational homogenization method. The two-scale FEM-FEM model is developed in which each particle is treated individually with the appropriate constitutive relations obtained from a representative volume element, kinematic conditions, contact constraints, and elimination of overlap satisfied for every particle. The method could be used in a variety of problems that can be represented using granular media.

关键词: homogenization     two-scale     representative volume element     compaction     granular assembly     finite element method    

A CFD study of the transport and fate of airborne droplets in a ventilated office: The role of droplet

《环境科学与工程前沿(英文)》 2022年 第16卷 第3期 doi: 10.1007/s11783-021-1465-8

摘要:

• Coulomb and Lennard−Jones forces were considered for droplet interactions.

关键词: Droplet interactions     Aerosols     Colloids     CFD     Transport     Fate    

Experimental study on bubble behavior and CFD simulation of large-scale slurry bubble column reactor

Haoyi SUN, Tao LI, Weiyong YING, Dingye FANG

《化学科学与工程前沿(英文)》 2010年 第4卷 第4期   页码 515-522 doi: 10.1007/s11705-010-0516-7

摘要: Slurry bubble column reactors (SBCR) is a three-phase fluidized reactor with outstanding advantages compared with other reactors and is difficult to scale-up due to lack of information on hydrodynamics and mass transfer over a wide range of operating conditions of commercial interest. In this paper, an experiment was conducted to investigate the bubble behavior in SBCR with a height of 5600 mm and an interior diameter of 480 mm. Bubble rise velocity, bubble diameter, and gas holdup in different radial and axial positions are measured in SBCR using four-channel conductivity probe. Tap water, air, and glass beads (mean diameter 75–150 μm) are used as liquid, gas, and solid phases, respectively. It shows that hydrodynamic parameters have good regularity in SBCR. Moreover, a commercial computational fluid dynamics (CFD) package, Fluent, was used to simulate the process in SBCR. The simulations were carried out using axi-symmetric 2-D grids. Data obtained from experiment and CFD simulation are compared, and results show that the tendency of simulation is almost uniform with the experiment, which can help to obtain further understanding about multiphase flow process and establish a model about the synthesis of alcohol ether fuel in SBCR.

关键词: SBCR     four-channel conductivity probe     hydrodynamics     CFD    

Microdamage study of granite under thermomechanical coupling based on the particle flow code

《结构与土木工程前沿(英文)》   页码 1413-1427 doi: 10.1007/s11709-023-0953-2

摘要: The thermomechanical coupling of rocks refers to the interaction between the mechanical and thermodynamic behaviors of rocks induced by temperature changes. The study of this coupling interaction is essential for understanding the mechanical and thermodynamic properties of the surrounding rocks in underground engineering. In this study, an improved temperature-dependent linear parallel bond model is introduced under the framework of a particle flow simulation. A series of numerical thermomechanical coupling tests are then conducted to calibrate the micro-parameters of the proposed model by considering the mechanical behavior of the rock under different thermomechanical loadings. Good agreement between the numerical results and experimental data are obtained, particularly in terms of the compression, tension, and elastic responses of granite. With this improved model, the thermodynamic response and underlying cracking behavior of a deep-buried tunnel under different thermal loading conditions are investigated and discussed in detail.

关键词: thermomechanical coupling effect     granite     improved linear parallel bond model     thermal property     particle flow code    

Characterization of aerodynamic performance of wind-lens turbine using high-fidelity CFD simulations

Islam HASHEM, Aida A. HAFIZ, Mohamed H. MOHAMED

《能源前沿(英文)》 2022年 第16卷 第4期   页码 661-682 doi: 10.1007/s11708-020-0713-0

摘要: Wind-lens turbines (WLTs) exhibit the prospect of a higher output power and more suitability for urban areas in comparison to bare wind turbines. The wind-lens typically comprises a diffuser shroud coupled with a flange appended to the exit periphery of the shroud. Wind-lenses can boost the velocity of the incoming wind through the turbine rotor owing to the creation of a low-pressure zone downstream the flanged diffuser. In this paper, the aerodynamic performance of the wind-lens is computationally assessed using high-fidelity transient CFD simulations for shrouds with different profiles, aiming to assess the effect of change of some design parameters such as length, area ratio and flange height of the diffuser shroud on the power augmentation. The power coefficient ( ) is calculated by solving the URANS equations with the aid of the SST model. Furthermore, comparisons with experimental data for validation are accomplished to prove that the proposed methodology could be able to precisely predict the aerodynamic behavior of the wind-lens turbine. The results affirm that wind-lens with cycloidal profile yield an augmentation of about 58% increase in power coefficient compared to bare wind turbine of the same rotor swept-area. It is also emphasized that diffusers (cycloid type) of small length could achieve a twice increase in power coefficient while maintaining large flange heights.

关键词: shroud     diffuser-augmented wind turbine (DAWT)     Betz limit     aerodynamics     computational fluid dynamics (CFD)    

3D finite element method (FEM) simulation of groundwater flow during backward erosion piping

Kristine VANDENBOER,Vera van BEEK,Adam BEZUIJEN

《结构与土木工程前沿(英文)》 2014年 第8卷 第2期   页码 160-166 doi: 10.1007/s11709-014-0257-7

摘要: Backward erosion piping is an important failure mechanism for cohesive water retaining structures which are founded on a sandy aquifer. At present, the prediction models for safety assessment are often based on 2D assumptions. In this work, a 3D numerical approach of the groundwater flow leading to the erosion mechanism of backward erosion piping is presented and discussed. Comparison of the 2D and 3D numerical results explicitly demonstrates the inherent 3D nature of the piping phenomenon. In addition, the influence of the seepage length is investigated and discussed for both piping initiation and piping progression. The results clearly indicate the superiority of the presented 3D numerical model compared to the established 2D approach. Moreover, the 3D numerical results enable a better understanding of the complex physical mechanism involved in backward erosion piping and thus can lead to a significant improvement in the safety assessment of water retaining structures.

关键词: backward erosion piping     groundwater flow     3D finite element method (FEM)    

Application of different CFD multiphase models to investigate effects of baffles and nanoparticles on

Ali SHAHMOHAMMADI,Arezou JAFARI

《化学科学与工程前沿(英文)》 2014年 第8卷 第3期   页码 320-329 doi: 10.1007/s11705-014-1437-7

摘要: In this work, the effect of baffles in a pipe on heat transfer enhancement was studied using computational fluid dynamics (CFD) in the presence of Al O nanoparticles which are dispersed into water. Fluid flow through the horizontal tube with uniform heat flux was simulated numerically and three dimensional governing partial differential equations were solved. To find an accurate model for CFD simulations, the results obtained by the single phase were compared with those obtained by three different multiphase models including Eulerian, mixture and volume of fluid (VOF) at Reynolds numbers in range of 600 to 3000, and two different nanoparticle concentrations (1% and 1.6%). It was found that multiphase models could better predict the heat transfer in nanofluids. The effect of baffles on heat transfer of nanofluid flow was also investigated through a baffled geometry. The numerical results show that at Reynolds numbers in the range of 600 to 2100, the heat transfer of nanofluid flowing in the geometry without baffle is greater than that of water flowing through a tube with baffle, whereas the difference between these effects (nanofluid and baffle) decreases with increasing the Reynolds number. At higher Reynolds numbers (2100–3000) the baffle has a greater effect on heat transfer enhancement than the nanofluid.

关键词: CFD simulation     heat transfer     nanofluid     baffle     single phase model     multiphase model    

CFD based combustion model for sewage sludge gasification in a fluidized bed

Yiqun WANG, Lifeng YAN

《化学科学与工程前沿(英文)》 2009年 第3卷 第2期   页码 138-145 doi: 10.1007/s11705-009-0050-7

摘要: Gasification is one potential way to use sewage sludge as renewable energy and solve the environmental problems caused by the huge amount of sewage sludge. In this paper, a three-dimensional Computational Fluid Dynamics (CFD) model has been developed to simulate the sewage sludge gasification process in a fluidized bed. The model describes the complex physical and chemical phenomena in the gasifier including turbulent flow, heat and mass transfer, and chemical reactions. The model is based on the Eulerian-Lagrangian concept using the non-premixed combustion modeling approach. In terms of the CFD software FLUENT, which represents a powerful tool for gasifier analysis, the simulations provide detailed information on the gas products and temperature distribution in the gasifier. The model sensitivity is analyzed by performing the model in a laboratory-scale fluidized bed in the literature, and the model validation is carried out by comparing with experimental data from the literature. Results show that reasonably good agreement was achieved. Effects of temperature and Equivalence Ratio (ER) on the quality of product syngas (H + CO) are also studied.

关键词: CFD     model     sewage sludge     gasification     syngas    

Research on acoustic-structure sensitivity using FEM and BEM

ZHANG Jun, ZHAO Wenzhong, ZHANG Weiying

《机械工程前沿(英文)》 2007年 第2卷 第1期   页码 62-67 doi: 10.1007/s11465-007-0010-1

摘要: Acoustic-structure sensitivity is used to predict the change of acoustic pressure when a structure design variable is changed. The sensitivity is significant for reducing noise of structure. Using FEM (finite element method) and BEM (boundary element method) acoustic-structure sensitivity was formulated and presented. The dynamic response and response velocity sensitivity with respect to structure design variable were carried out by using structural FEM, the acoustic response and acoustic pressure sensitivity with respect to structure velocity were carried out by using acoustic BEM. Then, acoustic-structure sensitivity was computed by linking velocity sensitivity in FEM and acoustic sensitivity in BEM. This method was applied to an empty box as an example. Acoustic pressure sensitivity with respect to structure thickness achieved in frequency ranges 1 100 Hz, and its change rule along with stimulating frequency and design variable were analyzed. Results show that acoustic-structure sensitivity method linked with FEM and BEM is effective and correct.

关键词: sensitivity method     BEM     acoustic pressure     pressure sensitivity     frequency    

FEM-based strain analysis study for multilayer sheet forming process

Rongjing ZHANG,Lihui LANG,Rizwan ZAFAR

《机械工程前沿(英文)》 2015年 第10卷 第4期   页码 373-379 doi: 10.1007/s11465-015-0371-9

摘要:

Fiber metal laminates have many advantages over traditional laminates (e.g., any type of fiber and resin material can be placed anywhere between the metallic layers without risk of failure of the composite fabric sheets). Furthermore, the process requirements to strictly control the temperature and punch force in fiber metal laminates are also less stringent than those in traditional laminates. To further explore the novel method, this study conducts a finite element method-based (FEM-based) strain analysis on multilayer blanks by using the 3A method. Different forming modes such as wrinkling and fracture are discussed by using experimental and numerical studies. Hydroforming is used for multilayer forming. The Barlat 2000 yield criteria and DYNAFORM/LS-DYNA are used for the simulations. Optimal process parameters are determined on the basis of fixed die-binder gap and variable cavity pressure. The results of this study will enhance the knowledge on the mechanics of multilayer structures formed by using the 3A method and expand its commercial applications.

关键词: finite element method (FEM)     strain analysis     multilayer sheet forming    

Simulation of bubble column reactors using CFD coupled with a population balance model

Tiefeng WANG

《化学科学与工程前沿(英文)》 2011年 第5卷 第2期   页码 162-172 doi: 10.1007/s11705-009-0267-5

摘要: Bubble columns are widely used in chemical and biochemical processes due to their excellent mass and heat transfer characteristics and simple construction. However, their fundamental hydrodynamic behaviors, which are essential for reactor scale-up and design, are still not fully understood. To develop design tools for engineering purposes, much research has been carried out in the area of computational fluid dynamics (CFD) modeling and simulation of gas-liquid flows. Due to the importance of the bubble behavior, the bubble size distribution must be considered in the CFD models. The population balance model (PBM) is an effective approach to predict the bubble size distribution, and great efforts have been made in recent years to couple the PBM into CFD simulations. This article gives a selective review of the modeling and simulation of bubble column reactors using CFD coupled with PBM. Bubble breakup and coalescence models due to different mechanisms are discussed. It is shown that the CFD-PBM coupled model with proper bubble breakup and coalescence models and interphase force formulations has the ability of predicting the complex hydrodynamics in different flow regimes and, thus, provides a unified description of both the homogeneous and heterogeneous regimes. Further study is needed to improve the models of bubble coalescence and breakup, turbulence modification in high gas holdup, and interphase forces of bubble swarms.

关键词: bubble column     computational fluid dynamics     bubble breakup and coalescence     population balance model     bubble size distribution    

标题 作者 时间 类型 操作

Simulation of steel beam under ceiling jet based on a wind–fire–structure coupling model

期刊论文

大功率刮板输送机阀控充液型液力偶合器研发

李国平,赵美,赵继云,张德生

期刊论文

Experimental and CFD analysis of nozzle position of subsonic ejector

Xilai ZHANG, Shiping JIN, Suyi HUANG, Guoqing TIAN

期刊论文

Numerical evaluation of group-pile foundation subjected to cyclic horizontal load

Youngji JIN, Xiaohua BAO, Yoshimitsu KONDO, Feng ZHANG,

期刊论文

Two-scale modeling of granular materials: A FEM-FEM approach

Yun-Zhu CAI, Yu-Ching WU

期刊论文

A CFD study of the transport and fate of airborne droplets in a ventilated office: The role of droplet

期刊论文

Experimental study on bubble behavior and CFD simulation of large-scale slurry bubble column reactor

Haoyi SUN, Tao LI, Weiyong YING, Dingye FANG

期刊论文

Microdamage study of granite under thermomechanical coupling based on the particle flow code

期刊论文

Characterization of aerodynamic performance of wind-lens turbine using high-fidelity CFD simulations

Islam HASHEM, Aida A. HAFIZ, Mohamed H. MOHAMED

期刊论文

3D finite element method (FEM) simulation of groundwater flow during backward erosion piping

Kristine VANDENBOER,Vera van BEEK,Adam BEZUIJEN

期刊论文

Application of different CFD multiphase models to investigate effects of baffles and nanoparticles on

Ali SHAHMOHAMMADI,Arezou JAFARI

期刊论文

CFD based combustion model for sewage sludge gasification in a fluidized bed

Yiqun WANG, Lifeng YAN

期刊论文

Research on acoustic-structure sensitivity using FEM and BEM

ZHANG Jun, ZHAO Wenzhong, ZHANG Weiying

期刊论文

FEM-based strain analysis study for multilayer sheet forming process

Rongjing ZHANG,Lihui LANG,Rizwan ZAFAR

期刊论文

Simulation of bubble column reactors using CFD coupled with a population balance model

Tiefeng WANG

期刊论文