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Application of python-based Abaqus preprocess and postprocess technique in analysis of gearbox vibration and noise reduction

Guilian YI, Yunkang SUI, Jiazheng DU

《机械工程前沿(英文)》 2011年 第6卷 第2期   页码 229-234 doi: 10.1007/s11465-011-0128-z

摘要:

To reduce vibration and noise, a damping layer and constraint layer are usually pasted on the inner surface of a gearbox thin shell, and their thicknesses are the main parameters in the vibration and noise reduction design. The normal acceleration of the point on the gearbox surface is the main index that can reflect the vibration and noise of that point, and the normal accelerations of different points can reflect the degree of the vibration and noise of the whole structure. The K-S function is adopted to process many points’ normal accelerations as the comprehensive index of the vibration characteristics of the whole structure, and the vibration acceleration level is adopted to measure the degree of the vibration and noise. Secondary development of the Abaqus preprocess and postprocess on the basis of the Python scripting programming automatically modifies the model parameters, submits the job, and restarts the analysis totally, which avoids the tedious work of returning to the Abaqus/CAE for modifying and resubmitting and improves the speed of the preprocess and postprocess and the computational efficiency.

关键词: Abaqus secondary development     Python language     vibration and noise reduction     K-S function     vibration acceleration level    

Morphological and mechanical characterization of a PMMA/CdS nanocomposite

Vishal MATHUR, Manasvi DIXIT, K.S. RATHORE, N. S. SAXENA, K.B. SHARMA

《化学科学与工程前沿(英文)》 2011年 第5卷 第2期   页码 258-263 doi: 10.1007/s11705-010-1014-7

摘要: Thick film of poly(methyl methacrylate) (PMMA)/CdS nanocomposite have been synthesized by the solution casting process. The nanostructure of the CdS particles has been ascertained through the small angle X-ray scattering (SAXS) technique. The surface morphological characterization of the PMMA/CdS nanocomposite has been done through scanning electron microscopy (SEM) analysis. The variation of mechanical loss factor (Tan ) with temperature and tensile properties of prepared samples have been studied using Dynamic Mechanical Analyzer (DMA). This study reveals that the glass transition temperature ( ), Young’s modulus, and fracture energy of the PMMA/CdS nanocomposite are greatly influenced by the existence of interfacial energetic interaction between dispersed CdS nanoparticles and the matrix of PMMA.

关键词: poly(methyl methacrylate) (PMMA)     filler nanoparticles     polymer semiconducting nanocomposite     tensile properties     glass transition temperature    

K型钢管混凝土节点疲劳性能试验研究

钟新谷,杨胜,石卫华

《中国工程科学》 2011年 第13卷 第9期   页码 97-100

摘要:

以湘潭四大桥桁架拱为工程背景,进行了三种规格的K型钢管混凝土节点的疲劳试验,基于热点应力计算了K型钢管混凝土节点的疲劳荷载幅值,表明热点应力法能够较好地评估钢管混凝土节点的疲劳寿命;试验表明K型钢管混凝土节点的疲劳性能明显优于K型钢管节点。在此基础上初步提出了K型钢管混凝土节点的S—N曲线,对建立K型钢管混凝土节点疲劳寿命设计准则具有一定的参考意义。

关键词: K型钢管混凝土节点     疲劳性能     S—N曲线    

满足k阶严格雪崩准则的多值逻辑函数的谱特征

郭锦辉,李世取

《中国工程科学》 2005年 第7卷 第12期   页码 45-48

摘要:

给出了剩余类环Zm上逻辑函数的k阶严格雪崩准则(SAC)的概念, 用概率方法证明了m值逻辑函数满足高阶严格雪崩准则时一定满足低阶严格雪崩准则, 并借助Chrestenson谱给出了m值逻辑函数满足k阶严格雪崩准则的一个充分必要条件。

关键词: m值逻辑函数     Chrestenson谱     自相关函数     严格雪崩准则    

Experimental investigation on heat transfer effect of conical strip inserts in a circular tube under laminar flow

ARULPRAKASAJOTHI,K. ELANGOVAN,K. HEMA CHANDRA REDDY,S. SURESH

《能源前沿(英文)》 2016年 第10卷 第2期   页码 136-142 doi: 10.1007/s11708-015-0389-z

摘要: The aim of this paper is to observe the Nusselt number and friction factor behavior of the circular tube with conical strip inserts as turbulators in a laminar flow condition, using staggered and non-staggered conical strips with three different twist ratios ( = 2, 3 and 5). The conical strip is inserted in the forward and backward direction individually compared to the flow of water which is the working fluid. The results indicate that the conical strip inserts increases the Nusselt number when compared to the plain surface tube. It is observed that the strip geometry has a major effect on the thermal performance of the circular tube. On examination of different strips for determining the enhancement of Nusselt number, the staggered conical strip with the twist ratio of = 3 has given a better result compared to the other two strips. Finally, correlations have been derived using regression analysis for predicting the Nusselt number and friction factor.

关键词: Nusselt number     friction factor     conical strip    

Polyhedral linkages obtained as assemblies of planar link groups

GÖkhan KİPER, Eres SÖYLEMEZ

《机械工程前沿(英文)》 2013年 第8卷 第1期   页码 3-9 doi: 10.1007/s11465-013-0363-6

摘要:

The study aims to devise means of obtaining polyhedral linkages for homothetic deployment of polyhedral shapes by embedding planar link groups in faces of the polyhedral shape of interest. The questions of which polyhedral shapes may be suitable for such a purpose and what are the compatibility conditions for spatially assembling planar link groups are addressed. Homohedral and tangential polyhedral shapes are found to be suitable for the task and some examples of linkages are worked out.

关键词: polyhedral linkages     homothety     homohedra     tangential polyhedra    

Bioleaching of copper from pre and post thermally activated low grade chalcopyrite contained ball mill spillage

Sandeep PANDA, Nilotpala PRADHAN, Umaballav MOHAPATRA, Sandeep K. PANDA, Swagat S. RATH, Danda S.SUKLA, Barada K. MISHRA

《环境科学与工程前沿(英文)》 2013年 第7卷 第2期   页码 281-293 doi: 10.1007/s11783-013-0484-5

摘要: Bioleaching of a low grade chalcopyrite (ball mill spillage material) was tested for copper recovery in shake flasks. The original samples (as received) were thermally activated (600°C, 30 min) to notice the change in physico-chemical and mineralogical characteristics of the host rock and subsequently its effect on copper recovery. A mixed culture of acidophilic chemolithotrophic bacterial consortium predominantly entailing strain was used for bioleaching studies and optimization of process parameters of both original and thermally activated samples. Mineralogical characterization studies indicated the presence of chalcopyrite, pyrite in the silicate matrix of the granitic rock. Field emission scanning electron microscopy coupled with Energy dispersive spectroscopy (FESEM-EDS) and X-ray Fluorescence (XRF) analysis indicated mostly SiO . With pH 2, pulp density 10% w/v, inoculum 10% v/v, temperature 30°C, 150 r·min , 49% copper could be recovered in 30 days from the finest particle size (-1+ 0.75 mm) of the original spillage sample. Under similar conditions 95% copper could be recovered from the thermally activated sample with the same size fraction in 10 days. The study revealed that thermal activation leads to volume expansion in the rock with the development of cracks, micro and macro pores on its surface, thereby enabling bacterial solution to penetrate more easily into the body, facilitating enhanced copper dissolution.

关键词: ball mill spillage     thermal activation     bioleaching     copper    

Biomechanics of knee joint – A review

Bhaskar Kumar MADETI,Srinivasa Rao CHALAMALASETTI,S K Sundara siva rao BOLLA PRAGADA

《机械工程前沿(英文)》 2015年 第10卷 第2期   页码 176-186 doi: 10.1007/s11465-014-0306-x

摘要:

The present paper is to know how the work is carried out in the field of biomechanics of knee. Various model formulations are discussed and further classified into mathematical model, two-dimensional model and three-dimensional model. Knee geometry is a crucial part of human body movement, in which how various views of knee is shown in different planes and how the forces act on tibia and femur are studied. It leads to know the forces acting on the knee joint. Experimental studies of knee geometry and forces acting on knee shown by various researchers have been discussed, and comparisons of results are made. In addition, static and dynamic analysis of knee has been also discussed respectively to some extent.

关键词: biomechanics     knee geometry     ligaments     squat     femorotibial joint     finite element method    

Detection of void and metallic inclusion in 2D piezoelectric cantilever beam using impedance measurements

S. SAMANTA, S. S. NANTHAKUMAR, R. K. ANNABATTULA, X. ZHUANG

《结构与土木工程前沿(英文)》 2019年 第13卷 第3期   页码 542-556 doi: 10.1007/s11709-018-0496-0

摘要: The aim of current work is to improve the existing inverse methodology of void-detection based on a target impedance curve, leading to quick-prediction of the parameters of single circular void. In this work, mode-shape dependent shifting phenomenon of peaks of impedance curve with change in void location has been analyzed. A number of initial guesses followed by an iterative optimization algorithm based on univariate method has been used to solve the problem. In each iteration starting from each initial guess, the difference between the computationally obtained impedance curve and the target impedance curve has been reduced. This methodology has been extended to detect single circular metallic inclusion in 2D piezoelectric cantilever beam. A good accuracy level was observed for detection of flaw radius and flaw-location along beam-length, but not the precise location along beam-width.

关键词: piezoelectricity     impedance curve     mode shapes     inverse problem     flaw detection     curve shifting    

Quantification of hydration products in cementitious materials incorporating silica nanoparticles

GOEL,S. K. BHATTACHARYYA,G. MISHRA

《结构与土木工程前沿(英文)》 2016年 第10卷 第2期   页码 162-167 doi: 10.1007/s11709-015-0315-9

摘要: In the present work, silica nanoparticles (30-70nm) were supplemented into cement paste to study their influence on degree of hydration, porosity and formation of different type of calcium-silicate-hydrate (C-S-H) gel. As the hydration time proceeds, the degree of hydration reach to 76% in nano-modified cement paste whereas plain cement achieve up to 63% at 28 days. An influence of degree of hydration on the porosity was also determined. In plain cement paste, the capillary porosity at 1hr is ~48%, whereas in silica nanoparticles added cement is ~35 % only, it revealed that silica nanoparticles refines the pore structure due to accelerated hydration mechanism leading to denser microstructure. Similarly, increasing gel porosity reveals the formation of more C-S-H gel. Furthermore, C-S-H gel of different Ca/Si ratio in hydrated cement paste was quantified using X-ray diffractometer and thermogravimetry. The results show that in presence of silica nanoparticles, ~24% C-S-H (Ca/Si<1.0) forms, leading to the formation of polymerised and compact C-S-H. In case of plain cement this type of C-S-H was completely absent at 28 days. These studies reveal that the hydration mechanism of the cement can be tuned with the incorporation of silica nanoparticles and thus, producing more durable cementitious materials.

关键词: degree of hydration     porosity     calcium-silicate-hydrate (C-S-H)     silica nanoparticles    

Solving multi-objective optimal power flow problem considering wind-STATCOM using differential evolution

Belkacem MAHDAD, K. SRAIRI

《能源前沿(英文)》 2013年 第7卷 第1期   页码 75-89 doi: 10.1007/s11708-012-0222-x

摘要: In this paper, a simple strategy based differential evolution was proposed for solving the problem of multi-objective environmental optimal power flow considering a hybrid model (Wind-Shunt-FACTS). The DE algorithm optimized simultaneously a combined vector control based active power of wind sources and reactive power of multi STATCOM exchanged with the electrical power system to minimize fuel cost and emissions. The proposed strategy was examined and applied to the standard IEEE 30-bus with smooth cost function to solve the problem of security environmental economic dispatch considering multi distributed hybrid model based wind and STATCOM controllers. In addition, the proposed approach was validated on a large practical electrical power system 40 generating units considering valve point effect. Simulation results demonstrate that choosing the installation of multi type of FACTS devices in coordination with many distributed wind sources is a vital research area.

关键词: differential evolution     multi-objective function     optimal power flow     economic dispatch     valve point effect     environment     wind source     STATCOM    

3S技术在区域生态功能区划中的应用——以河南省濮阳市为案例

卞有生,蔡博峰,赵楠

《中国工程科学》 2005年 第7卷 第12期   页码 54-60

摘要:

生态功能区划是区域社会经济协调发展的基础性工作,3S技术则是保证区划科学与准确的重要技术手段。以河南省濮阳市为例,介绍了3S技术在区域生态功能区划中的应用及其优势与特点,即数据的准确性、现势性和科学性得到进一步提高,而且空间分析功能充分实现了不同权重生态因子的叠加,同时在区划过程中充分考虑生态格局对生态功能的影响

关键词: 生态功能区划     3S     空间分析     生态格局    

Fatigue crack growth simulations of 3-D linear elastic cracks under thermal load by XFEM

SINGH,S. K. YADAV

《结构与土木工程前沿(英文)》 2015年 第9卷 第4期   页码 359-382 doi: 10.1007/s11709-015-0304-z

摘要: This paper deals with the fatigue crack growth simulations of three-dimensional linear elastic cracks by XFEM under cyclic thermal load. Both temperature and displacement approximations are extrinsically enriched by Heaviside and crack front enrichment functions. Crack growth is modelled by successive linear extensions, and the end points of these linear extensions are joined by cubic spline segments to obtain a modified crack front. Different crack geometries such as planer, non-planer and arbitrary spline shape cracks are simulated under thermal shock, adiabatic and isothermal loads to reveal the sturdiness and versatility of the XFEM approach.

关键词: 3-D cracks     fatigue life     Paris law     thermal load     XFEM    

Unit commitment using dynamic programming–an exhaustive working of both classical and stochastic approach

Balasubramaniyan SARAVANAN, Surbhi SIKRI, K. S. SWARUP, D. P. KOTHARI

《能源前沿(英文)》 2013年 第7卷 第3期   页码 333-341 doi: 10.1007/s11708-013-0259-5

摘要: In the present electricity market, where renewable energy power plants have been included in the power systems, there is a lot of unpredictability in the demand and generation. There are many conventional and evolutionary programming techniques used for solving the unit commitment (UC) problem. Dynamic programming (DP) is a conventional algorithm used to solve the deterministic problem. In this paper DP is used to solve the stochastic model of UC problem. The stochastic modeling for load and generation side has been formulated using an approximate state decision approach. The programs were developed in a MATLAB environment and were extensively tested for a four-unit eight-hour system. The results obtained from these techniques were validated with the available literature and outcome was good. The commitment is in such a way that the total cost is minimal. The novelty of this paper lies in the fact that DP is used for solving the stochastic UC problem.

关键词: unit commitment (UC)     deterministic     stochastic     dynamic programming (DP)     optimization     state diagram    

Marble epistyles under shear: an experimental study of the role of “Relieving Space”

TRIANTIS, S. K. KOURKOULIS

《结构与土木工程前沿(英文)》 2019年 第13卷 第4期   页码 767-786 doi: 10.1007/s11709-019-0515-9

摘要: The mechanical response of mutually interconnected epistyles is studied experimentally. The specimens are made of two marble blocks connected to each other with an “I”-shaped titanium connector placed in grooves sculptured on the blocks and covered with cementitious material. The specific way of connecting epistyles simulates the one used by scientists restoring the ancient “connections” of the epistyles of the Parthenon Temple. This “connection,” although designed to sustain mainly tensile loading, undertakes, also, shear load, in case of excitations imposing to the epistyles displacements normal to the connector’s axis. Attention is focused to enlighten the role of a novel design technique aiming to relieve the stress field around the connector. According to this technique, part of the connector’s web is left uncovered, forming the so-called “ ,” assisting the unconstrained deformation of the connector. Both traditional and innovative sensing techniques were employed in an effort to obtain data from the interior of the three-material-complex (marble-cementitious material-titanium). Analysis of the data indicated that the “Relieving Space” reduces the overall stiffness of the system, protecting marble in case of over-loading. Moreover, it was concluded that the innovative techniques employed provide pre-failure indicators well in advance of the catastrophic failure of the specimens.

关键词: monuments of cultural heritage     marble epistyles     pressure stimulated currents     acoustic emission     digital image correlation    

标题 作者 时间 类型 操作

Application of python-based Abaqus preprocess and postprocess technique in analysis of gearbox vibration and noise reduction

Guilian YI, Yunkang SUI, Jiazheng DU

期刊论文

Morphological and mechanical characterization of a PMMA/CdS nanocomposite

Vishal MATHUR, Manasvi DIXIT, K.S. RATHORE, N. S. SAXENA, K.B. SHARMA

期刊论文

K型钢管混凝土节点疲劳性能试验研究

钟新谷,杨胜,石卫华

期刊论文

满足k阶严格雪崩准则的多值逻辑函数的谱特征

郭锦辉,李世取

期刊论文

Experimental investigation on heat transfer effect of conical strip inserts in a circular tube under laminar flow

ARULPRAKASAJOTHI,K. ELANGOVAN,K. HEMA CHANDRA REDDY,S. SURESH

期刊论文

Polyhedral linkages obtained as assemblies of planar link groups

GÖkhan KİPER, Eres SÖYLEMEZ

期刊论文

Bioleaching of copper from pre and post thermally activated low grade chalcopyrite contained ball mill spillage

Sandeep PANDA, Nilotpala PRADHAN, Umaballav MOHAPATRA, Sandeep K. PANDA, Swagat S. RATH, Danda S.SUKLA, Barada K. MISHRA

期刊论文

Biomechanics of knee joint – A review

Bhaskar Kumar MADETI,Srinivasa Rao CHALAMALASETTI,S K Sundara siva rao BOLLA PRAGADA

期刊论文

Detection of void and metallic inclusion in 2D piezoelectric cantilever beam using impedance measurements

S. SAMANTA, S. S. NANTHAKUMAR, R. K. ANNABATTULA, X. ZHUANG

期刊论文

Quantification of hydration products in cementitious materials incorporating silica nanoparticles

GOEL,S. K. BHATTACHARYYA,G. MISHRA

期刊论文

Solving multi-objective optimal power flow problem considering wind-STATCOM using differential evolution

Belkacem MAHDAD, K. SRAIRI

期刊论文

3S技术在区域生态功能区划中的应用——以河南省濮阳市为案例

卞有生,蔡博峰,赵楠

期刊论文

Fatigue crack growth simulations of 3-D linear elastic cracks under thermal load by XFEM

SINGH,S. K. YADAV

期刊论文

Unit commitment using dynamic programming–an exhaustive working of both classical and stochastic approach

Balasubramaniyan SARAVANAN, Surbhi SIKRI, K. S. SWARUP, D. P. KOTHARI

期刊论文

Marble epistyles under shear: an experimental study of the role of “Relieving Space”

TRIANTIS, S. K. KOURKOULIS

期刊论文