资源类型

期刊论文 443

会议视频 7

年份

2024 1

2023 45

2022 45

2021 44

2020 39

2019 27

2018 21

2017 23

2016 25

2015 23

2014 17

2013 10

2012 13

2011 12

2010 9

2009 12

2008 19

2007 20

2006 10

2005 5

展开 ︾

关键词

力学性能 8

BP神经网络 2

力学模型 2

加速遗传算法 2

增材制造 2

数值模拟 2

斜拉桥 2

无损检测 2

智能制造 2

机械结构 2

现场监测 2

2021全球工程前沿 1

3D打印 1

5% 法 1

AFHW模型 1

ANSYS 1

BMI树脂 1

CAD 装配模型 1

CAD/CAE一体化 1

展开 ︾

检索范围：

排序： 展示方式：

Thermo-mechanical simulation of frost heave in saturated soils

《结构与土木工程前沿（英文）》   页码 1400-1412 doi: 10.1007/s11709-023-0990-x

摘要： Roads are exposed to various degradation mechanisms during their lifetime. The pavement deterioration caused by the surrounding environment is particularly severe in winter when the humidity and subfreezing temperatures prevail. Frost heave-induced damage is one of the winter-related pavement deterioration. It occurs when the porewater in the soil is exposed to freezing temperatures. The study of frost heave requires conducting a multiphysics analysis, considering the thermal, mechanical, and hydraulic fields. This paper presents the use of a coupled thermo-mechanical approach to simulate frost heave in saturated soils. A function predicting porosity evolution is implemented to couple the thermal and mechanical field analyses. This function indirectly considers the effect of the water seepage inside the soil. Different frost heave scenarios with uniform and non-uniform boundary conditions are considered to demonstrate the capabilities of the method. The results of the simulations indicate that the thermo-mechanical model captures various processes involved in the frost heave phenomenon, such as water fusion, porosity variation, cryogenic suction force generation, and soil expansion. The characteristics and consequences of each process are determined and discussed separately. Furthermore, the results show that non-uniform thermal boundaries and presence of a culvert inside the soil result in uneven ground surface deformations.

关键词： frost heave     multiphysics analysis     thermo-mechanical approach     saturated soils    

HTML PDF 收藏

Effect of graphene and its derivatives on thermo-mechanical properties of phase change materials and

《能源前沿（英文）》 2022年 第16卷 第2期   页码 150-186 doi: 10.1007/s11708-021-0795-3

摘要： Phase change materials (PCMs) play a leading role in overcoming the growing need of advanced thermal management for the storage and release of thermal energy which is to be used for different solar applications. However, the effectiveness of PCMs is greatly affected by their poor thermal conductivity. Therefore, in the present review the progress made in deploying the graphene (Gr) in PCMs in the last decade for providing the solution to the aforementioned inadequacy is presented and discussed in detail. Gr and its derivatives ((Gr oxide (GO), Gr aerogel (GA) and Gr nanoplatelets (GNPs)) based PCMs can improve the thermal conductivity and shape stability, which may be attributed to the extra ordinary thermo-physical properties of Gr. Moreover, it is expected from this review that the advantages and disadvantages of using Gr nanoparticles provide a deep insight and help the researchers in finding out the exact basic properties and finally the applications of Gr can be enhanced.

关键词： phase change materials (PCMs)     graphene     thermal conductivity     characterization    

HTML PDF 收藏

基于有限变形理论的齿轮楔横轧制坯热力耦合模拟

应富强,潘孝勇,李敏

《中国工程科学》 2007年 第9卷 第7期   页码 47-52

摘要：

楔横轧齿轮轧制成形是一个全新的课题，在轧制过程中轧件的变形、温度场及力能参数都有待研究。将楔横轧技术与齿轮范成加工原理相结合，设计了楔横轧齿轮轧制的模具，给出了楔横轧齿轮轧制成形热力耦合本构模型，并在SuperForm平台对轧制成形过程进行了有限元模拟，获得了轧件在成形过程中的变形规律、温度场分布及力能参数变化等数据，详细分析了数值模拟结果，为进一步研究齿轮楔横轧制坯提供参考。

关键词： 楔横轧     齿轮     热力耦合     有限元    

HTML PDF 收藏

An extended thermo-mechanically coupled algorithm for simulation of superelasticity and shape memory

S. HASHEMI,H. AHMADIAN,S. MOHAMMADI

《结构与土木工程前沿（英文）》 2015年 第9卷 第4期   页码 466-477 doi: 10.1007/s11709-015-0300-3

摘要： Thermo-mechanical coupling in shape memory alloys is a very complicated phenomenon. The heat generation/absorption during forward/reverse transformation can lead to temperature-dependent variation of its mechanical behavior in the forms of superelasticity and shape memory effect. However, unlike the usual assumption, slow loading rate cannot guarantee an isothermal process. A two-dimensional thermo-mechanically coupled algorithm is proposed based on the original model of Lagoudas to efficiently model both superelasticity and shape memory effects and the influence of various strain rates, aspect ratios and boundary conditions. To implement the coupled model into a finite element code, a numerical staggered algorithm is employed. A number of simulations are performed to verify the proposed approach with available experimental and numerical data and to assess its efficiency in solving complex SMA problems.

关键词： shape memory alloy     thermo-mechanical coupling     superplasticity     shape memory effect    

HTML PDF 收藏

Residual stresses in coating-based systems, part I: Mechanisms and analytical modeling

ZHANG Xiancheng, WU Yixiong, XU Binshi, WANG Haidou

《机械工程前沿（英文）》 2007年 第2卷 第1期   页码 1-12 doi: 10.1007/s11465-007-0001-2

摘要： Thin films and multi-layered coatings comprised of different classes of materials are often used for various functional devices. The thermo-mechanical integrity of these systems is becoming a major concern and is strongly related to the residual stresses because of the fabrication processes. In this paper, the sources of the residual stresses in the coating-based systems and the concept of misfit strain were briefly reviewed. Analytical models were developed to predict the residual stresses in multi-layered film structures or coating-based systems using the force and moment balances. In addition, the residual stress distributions in the func tionally and compositionally graded coatings were also analyzed.

关键词： briefly     different     thermo-mechanical integrity     addition     residual    

HTML PDF 收藏

Finite element modeling of thermo-active diaphragm walls

Yi RUI, Mei YIN

《结构与土木工程前沿（英文）》 2020年 第14卷 第3期   页码 646-663 doi: 10.1007/s11709-020-0584-9

摘要： There are two major challenges faced by modern society: energy security, and lowering carbon dioxide gas emissions. Thermo-active diaphragm walls have a large potential to remedy one of these problems, since they are a renewable energy technology that uses underground infrastructure as a heat exchange medium. However, extensive research is required to determine the effects of cyclic heating and cooling on their geotechnical and structural performance. In this paper, a series of detailed finite element analyses are carried out to capture the fully coupled thermo-hydro-mechanical response of the ground and diaphragm wall. It is demonstrated that the thermal operation of the diaphragm wall causes changes in soil temperature, thermal expansion/shrinkage of pore water, and total stress applied on the diaphragm wall. These, in turn, cause displacements of the diaphragm wall and variations of the bending moments. However, these effects on the performance of diaphragm wall are not significant. The thermally induced bending strain is mainly governed by the temperature differential and uneven thermal expansion/shrinkage across the wall.

关键词： thermo-active diaphragm wall     finite element analysis     thermo-hydro-mechanical coupling     ground source heat pump    

HTML PDF 收藏

A bionic approach for the mechanical and electrical decoupling of an MEMS capacitive sensor in ultralow

《机械工程前沿（英文）》 2023年 第18卷 第2期 doi: 10.1007/s11465-023-0747-1

摘要： Capacitive sensors are efficient tools for biophysical force measurement, which is essential for the exploration of cellular behavior. However, attention has been rarely given on the influences of external mechanical and internal electrical interferences on capacitive sensors. In this work, a bionic swallow structure design norm was developed for mechanical decoupling, and the influences of structural parameters on mechanical behavior were fully analyzed and optimized. A bionic feather comb distribution strategy and a portable readout circuit were proposed for eliminating electrostatic interferences. Electrostatic instability was evaluated, and electrostatic decoupling performance was verified on the basis of a novel measurement method utilizing four complementary comb arrays and application-specific integrated circuit readouts. An electrostatic pulling experiment showed that the bionic swallow structure hardly moved by 0.770 nm, and the measurement error was less than 0.009% for the area-variant sensor and 1.118% for the gap-variant sensor, which can be easily compensated in readouts. The proposed sensor also exhibited high resistance against electrostatic rotation, and the resulting measurement error dropped below 0.751%. The rotation interferences were less than 0.330 nm and (1.829 × 10−7)°, which were 35 times smaller than those of the traditional differential one. Based on the proposed bionic decoupling method, the fabricated sensor exhibited overwhelming capacitive sensitivity values of 7.078 and 1.473 pF/µm for gap-variant and area-variant devices, respectively, which were the highest among the current devices. High immunity to mechanical disturbances was maintained simultaneously, i.e., less than 0.369% and 0.058% of the sensor outputs for the gap-variant and area-variant devices, respectively, indicating its great performance improvements over existing devices and feasibility in ultralow biomedical force measurement.

关键词： micro-electro-mechanical system capacitive sensor     bionics     operation instability     mechanical and electrical decoupling     biomedical force measurement    

HTML PDF 收藏

Analytical approach to robust design of nonlinear mechanical systems

Jian ZHANG, Nengsheng BAO, Guojun ZHANG, Peihua GU

《机械工程前沿（英文）》 2009年 第4卷 第2期   页码 203-214 doi: 10.1007/s11465-009-0022-0

摘要： The robustness of mechanical systems is influenced by various factors. Their effects must be understood for designing robust systems. This paper proposes a model for describing the relationships among functional requirements, structural characteristics, design parameters and uncontrollable variables of nonlinear systems. With this model, the sensitivity of systems was analyzed to formulate a system sensitivity index and robust sensitivity matrix to determine the importance of the factors in relation to the robustness of systems. Based on the robust design principle, an optimization model was developed. Combining this optimization model and the Taguchi method for robust design, an analysis was carried out to reveal the characteristics of the systems. For a nonlinear mechanical system, relationships among structural characteristics of the system, design parameters, and uncontrollable variables can be formulated as a mathematical function. The characteristics of the system determine how design parameters affect the functional requirements of the system. Consequently, they affect the distribution of system performance functions. Nonlinearity of the system can facilitate the selection of design parameters to achieve the required functional requirements.

关键词： robust     design     nonlinear    

HTML PDF 收藏

An approach for mechanical fault classification based on generalized discriminant analysis

LI Wei-hua, SHI Tie-lin, YANG Shu-zi

《机械工程前沿（英文）》 2006年 第1卷 第3期   页码 292-298 doi: 10.1007/s11465-006-0022-2

摘要： To deal with pattern classification of complicated mechanical faults, an approach to multi-faults classification based on generalized discriminant analysis is presented. Compared with linear discriminant analysis (LDA), generalized discriminant analysis (GDA), one of nonlinear discriminant analysis methods, is more suitable for classifying the linear non-separable problem. The connection and difference between KPCA (Kernel Principal Component Analysis) and GDA is discussed. KPCA is good at detection of machine abnormality while GDA performs well in multi-faults classification based on the collection of historical faults symptoms. When the proposed method is applied to air compressor condition classification and gear fault classification, an excellent performance in complicated multi-faults classification is presented.

关键词： generalized discriminant     non-separable     abnormality     classification     multi-faults classification    

HTML PDF 收藏

Isogeometric analysis of coupled thermo-elastodynamic problems under cyclic thermal shock

Asghar AMANI DASHLEJEH

《结构与土木工程前沿（英文）》 2019年 第13卷 第2期   页码 397-405 doi: 10.1007/s11709-018-0473-7

摘要： The isogeometric analysis (IGA) method was extended for the solution of the coupled thermo-elastodynamic equations. The dimensionless formulation was accepted in discretization of the uncoupled and coupled thermoelasticity equations and the Generalized Newmark method was used in the time integration procedure. First, the performance of the proposed method was verified against a two-dimensional benchmark example subjected to constant thermal shock with available exact analytical solutions. Then a two-dimensional half-space benchmark example under thermal shock was solved. Finally, cyclic thermal shock (CTS) loading was applied on the half-space problem. The results dedicated that IGA can be used as a suitable approach in the analysis of the general thermomechanical problems.

关键词： isogeometric analysis     coupled thermo-elastodynamic     dynamic analysis     generalized newmark     cyclic thermal shock    

HTML PDF 收藏

Free vibration analysis of functionally graded porous curved nanobeams on elastic foundation in hygro–thermo–magnetic

《结构与土木工程前沿（英文）》 2023年 第17卷 第4期   页码 584-605 doi: 10.1007/s11709-023-0916-7

摘要： Herein, a two-node beam element enriched based on the Lagrange and Hermite interpolation function is proposed to solve the governing equation of a functionally graded porous (FGP) curved nanobeam on an elastic foundation in a hygro–thermo–magnetic environment. The material properties of curved nanobeams change continuously along the thickness via a power-law distribution, and the porosity distributions are described by an uneven porosity distribution. The effects of magnetic fields, temperature, and moisture on the curved nanobeam are assumed to result in axial loads and not affect the mechanical properties of the material. The equilibrium equations of the curved nanobeam are derived using Hamilton’s principle based on various beam theories, including the classical theory, first-order shear deformation theory, and higher-order shear deformation theory, and the nonlocal elasticity theory. The accuracy of the proposed method is verified by comparing the results obtained with those of previous reliable studies. Additionally, the effects of different parameters on the free vibration behavior of the FGP curved nanobeams are investigated comprehensively.

关键词： functionally graded porous material     curved nanobeam     hygro–thermo–magnetic     enriched finite element method    

HTML PDF 收藏

Simulation and experimental improvement on a small-scale Stirling thermo-acoustic engine

Mao CHEN,Yonglin JU

《能源前沿（英文）》 2016年 第10卷 第1期   页码 37-45 doi: 10.1007/s11708-015-0390-6

摘要： Compared with the traditional engines, the thermo-acoustic engines are relatively new and can act as the linear compressors for refrigerators. Many institutes have shown great interest in this kind of machine for its absence of moving mechanical part. In this paper, the influence of the dimensions of the main parts of the small-scale Stirling thermo-acoustic engine was numerically simulated using a computer code called DeltaEC. The resonator and the resonator cavity were found to be the most convenient and effective in improving the performance of the engine. Based on the numerical simulation, a small-scale Stirling thermo-acoustic engine were constructed and experimentally investigated. Currently, with a resonator length of only 1 m, the working frequency of the engine was decreased to 90 Hz and the onset temperature difference was decreased to 198.2 K.

关键词： thermo-acoustic Stirling engine     small-scale     simulation     experiment    

HTML PDF 收藏

Thermo-elastic extended meshfree method for fracture without crack tip enrichment

A. ASADPOUR

《结构与土木工程前沿（英文）》 2015年 第9卷 第4期   页码 441-447 doi: 10.1007/s11709-015-0319-5

摘要： This is the first manuscript presenting an extended meshfree method for thermo- elastic fracture which does not exploit a crack tip enrichment. The crack is modeled by partition of unity enrichment of the displacement and temperature field. Only a step function is employed that facilitates the implementation. To ensure that crack tip is at the correct position, a Lagrange multiplier field ahead of the crack tip is introduced along a line. The Lagrange multiplier nodal parameters are discretised with the available meshfree functions. Two benchmark examples illustrate the efficiency of the method.

关键词： meshfree method     thermo-elasticity    

HTML PDF 收藏

Synthesis and characterization of biodegradable thermoplastic elastomers derived from N′,N-bis (2-carboxyethyl)-pyromellitimide, poly(butylene succinate) and polyethylene glycol

Jiaojiao Shang, Guo Yao, Ronghui Guo, Wei Zheng, Long Gu, Jianwu Lan

《化学科学与工程前沿（英文）》 2018年 第12卷 第3期   页码 457-466 doi: 10.1007/s11705-018-1716-9

摘要：

Biodegradable poly(ether-imide-ester) elastomers were synthesized from succinic acid, 1,4-butanediol, polyethylene glycol 1000 and N′,N-bis(2-carboxyethyl)-pyromellitimide which was derived from pyromellitic dianhydride and glycine. The chemical structures, crystallinities, thermal stabilities, mechanical properties, hydrophilicities and biodegradabilities of these elastomers were investigated. The hard segments of the linear aliphatic poly(ether-ester) exhibited monoclinic chain packing. Increasing the amount of aromatic bisimide moieties in the poly(ether-ester) reduced the crystallinity of the material and improved the thermal stability and tensile strength of the elastomers. In addition, introducing a suitable amount of aromatic bisimide moieties into the poly(ether-ester) backbones endowed the elastomers with improved biodegradability but too many aromatic bisimide groups reduced the biodegradability of the elastomers.

关键词： thermoplastic elastomers     biodegradability     thermo-stability     mechanical property     aromatic bisimide moiety    

HTML PDF 收藏

Nano thermo-hydrodynamics method for investigating cell membrane fluidity

YANG Yang, LIU Jing

《能源前沿（英文）》 2008年 第2卷 第2期   页码 121-128 doi: 10.1007/s11708-008-0033-2

摘要： As a barrier to compartmentalize cells, membranes form the interface between a cell and its surroundings. The essential function of a membrane is to maintain a relatively stable environment in the cell, exchange substances selectively and transfer energy and information continually from the outside. It is intriguing that above the phase transition temperature, the membrane lipid molecule will have three modes–lateral diffusion, rotational movement and flip-flop activity. These thermodynamic processes are vital to cell existence, growth, division, differentiation and are also responsible for hundreds of thousands of phenomena in life. Previously, species transport across the membrane was interpreted mainly from a phenomenological view using a lumped system model. Therefore, detailed flow processes occurred in the membrane domain and clues related to life mechanism were not sufficiently tackled. Such important issues can be clarified by modeling nano scale thermal hydrodynamics over the gap space of a cell membrane. Previously observed complex membrane behaviors will be shown in this paper and explained by the thermally induced fluidic convections inside the membrane. A correlation between nano scale hydrodynamics, non-equilibrium thermodynamics and cell membrane activities is set up. The disclosed mechanisms are expected to provide a new viewpoint on the interaction between intracellular and extracellular processes through the membrane.

关键词： responsible     phenomenological     phenomena     modes–lateral diffusion     differentiation    

HTML PDF 收藏

标题 作者 时间 类型 操作

Thermo-mechanical simulation of frost heave in saturated soils

期刊论文

Effect of graphene and its derivatives on thermo-mechanical properties of phase change materials and

期刊论文

基于有限变形理论的齿轮楔横轧制坯热力耦合模拟

应富强,潘孝勇,李敏

期刊论文

An extended thermo-mechanically coupled algorithm for simulation of superelasticity and shape memory

S. HASHEMI,H. AHMADIAN,S. MOHAMMADI

期刊论文

Residual stresses in coating-based systems, part I: Mechanisms and analytical modeling

ZHANG Xiancheng, WU Yixiong, XU Binshi, WANG Haidou

期刊论文

Finite element modeling of thermo-active diaphragm walls

Yi RUI, Mei YIN

期刊论文

A bionic approach for the mechanical and electrical decoupling of an MEMS capacitive sensor in ultralow

期刊论文

Analytical approach to robust design of nonlinear mechanical systems

Jian ZHANG, Nengsheng BAO, Guojun ZHANG, Peihua GU

期刊论文

An approach for mechanical fault classification based on generalized discriminant analysis

LI Wei-hua, SHI Tie-lin, YANG Shu-zi

期刊论文

Isogeometric analysis of coupled thermo-elastodynamic problems under cyclic thermal shock

Asghar AMANI DASHLEJEH

期刊论文

Free vibration analysis of functionally graded porous curved nanobeams on elastic foundation in hygro–thermo–magnetic

期刊论文

Simulation and experimental improvement on a small-scale Stirling thermo-acoustic engine

Mao CHEN,Yonglin JU

期刊论文

Thermo-elastic extended meshfree method for fracture without crack tip enrichment

A. ASADPOUR

期刊论文

Synthesis and characterization of biodegradable thermoplastic elastomers derived from N′,N-bis (2-carboxyethyl)-pyromellitimide, poly(butylene succinate) and polyethylene glycol

Jiaojiao Shang, Guo Yao, Ronghui Guo, Wei Zheng, Long Gu, Jianwu Lan

期刊论文

Nano thermo-hydrodynamics method for investigating cell membrane fluidity

YANG Yang, LIU Jing

期刊论文