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Russian school of the theory and geometry of gearing: Its origin and golden period (1935 --1975)

Dmitry BABICHEV,Sergey LAGUTIN,Natalya BARMINA

《机械工程前沿（英文）》 2016年 第11卷 第1期   页码 44-59 doi: 10.1007/s11465-015-0360-z

摘要：

During the second half of the twentieth century, Soviet scientists were among the world leaders in the theory and geometry of gearing or the theoretical fundamentals of designing gears and gear-cutting tools. The authors of the current paper review works related to the development of the theory of gearing (TG) written in Russian from the mid-1930s to the present. Overall, the review covers more than 400 publications of nearly 200 authors (among more than 1000 studied works). This review involves some works on gear strength and accuracy to attract more experts.

This paper presents a short list of works from the seventeenth century to the nineteenth century and discusses the basic concepts of the TG. This paper also includes a review of more than 160 papers in Russian for the period of 1935–1975, which is the “golden age” of the TG. The main features and achievements during this period are also considered.

The distinctive feature of this review is the use of diagrams that visually present TG experts and the dates and themes of their published works. The diagrams also show the following aspects: 1) The most popular and important themes in a specific period, 2) the most important publications on the themes of interest to readers, and 3) the direction of the works and scope of interests of every researcher.

关键词： theory of gearing (TG)     gear geometry     generating surface     gear synthesis     gear analysis    

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A new proof of Honeycomb Conjecture by fractal geometry methods

Tong ZHANG, Kai DING

《机械工程前沿（英文）》 2013年 第8卷 第4期   页码 367-370 doi: 10.1007/s11465-013-0273-7

摘要：

Based on fractal geometry, we put forward a concise and straightforward method to prove Honeycomb Conjecture—a classical mathematic problem. Hexagon wins the most efficient covering unit in the two- dimensional space, compared with the other two covering units—triangle and square. From this point of view, honeycomb is treated as a hierarchical fractal structure that fully fills the plane. Therefore, the total side length and area are easily calculated and from the results, the covering efficiency of each possible unit is provided quantitatively.

关键词： Honeycomb Conjecture     fractal geometry     hierarchical fractal structure    

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Transmission probability method based on triangle meshes for solving the unstructured geometry neutron

WU Hongchun, LIU Pingping, ZHOU Yongqiang, CAO Liangzhi

《能源前沿（英文）》 2007年 第1卷 第2期   页码 158-166 doi: 10.1007/s11708-007-0020-z

摘要： The fuel assembly or core with unstructured geometry is frequently used in the advanced reactor. To calculate the fuel assembly, the transmission probability method (TPM) is widely used. However, the rectangular or hexagonal meshes are mainly used in the TPM codes for the normal core structure. The triangle meshes are most useful for expressing the complicated unstructured geometry. Even though the finite element method and Monte-Carlo method are well suited for solving the unstructured geometry problem, they are very time-consuming. Therefore, a TPM code based on the triangle meshes is developed here. This code was applied to the hybrid fuel geometry, and compared with the results of the MCNP code and other codes. The results of the comparison were consistent with each other. The TPM with triangle meshes can thus be applied to the two-dimensional arbitrary fuel assembly.

关键词： unstructured geometry     assembly     transmission probability     TPM     rectangular    

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Experimental studies of ash film fractions based on measurement of cenospheres geometry in pulverized

Siqi LIU, Yanqing NIU, Liping WEN, Yang LIANG, Bokang YAN, Denghui WANG, Shi’en HUI

《能源前沿（英文）》 2021年 第15卷 第1期   页码 91-98 doi: 10.1007/s11708-020-0806-9

摘要： In pulverized coal particle combustion, part of the ash forms the ash film and exerts an inhibitory influence on combustion by impeding the diffusion of oxygen to the encapsulated char core, while part of the ash diffuses toward the char core. Despite the considerable ash effects on combustion, the fraction of ash film still remains unclear. However, the research of the properties of cenospheres can be an appropriate choice for the fraction determination, being aware that the formation of cenospheres is based on the model of coal particles with the visco-plastic ash film and a solid core. The fraction of ash film is the ratio of the measuring mass of ash film and the total ash in coal particle. In this paper, the Huangling bituminous coal with different sizes was burnt in a drop-tube furnace at 1273, 1473, and 1673 K with air as oxidizer. A scanning electron microscope (SEM) and cross-section analysis have been used to study the geometry of the collected cenospheres and the effects of combustion parameters on the fraction of ash film. The results show that the ash film fraction increases with increasing temperature and carbon conversion ratio but decreases with larger sizes of coal particles. The high fraction of ash film provides a reasonable explanation for the extinction event at the late burnout stage. The varied values of ash film fractions under different conditions during the dynamic combustion process are necessary for further development of kinetic models.

关键词： ash film fraction     cenospheres     coal combustion     fly ash    

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特大跨度斜拉桥施工几何控制原理的数值验证

黄灿,卜一之,张清华

《中国工程科学》 2009年 第11卷 第1期   页码 87-91

摘要：

以苏通长江大桥为研究对象，通过数值仿真分析验证了几何控制原理的正确性。通过对施工过程中临时荷载和环境温度对于结构线形影响的系统分析和研究结果表明，在考虑施工全过程几何非线性影响的条件下，临时荷载及环境温度等因素仅影响施工过程中的结构状态，基本不影响成桥的结构线形和内力状态，几何控制原理适用于超大斜拉桥施工控制，采用几何控制原理能够获得良好的施工控制结果。

关键词： 斜拉桥     几何控制     几何非线性     数值验证    

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Experimental study of the effects of structured surface geometry on water spray cooling performance in

Minghou LIU, Yaqing WANG, Dong LIU, Kan XU, Yiliang CHEN

《能源前沿（英文）》 2011年 第5卷 第1期   页码 75-82 doi: 10.1007/s11708-010-0014-0

摘要： Experiments were conducted to study the effects of enhanced surfaces on heat transfer performance during water spray cooling in non-boiling regime. The surface enhancement is straight fin. The structures were machined on the top surface of heated copper blocks with a cross-sectional area of 10 mm×10 mm. The spray was performed using Unijet full cone nozzles with a volumetric flux of 0.044–0.053 m /(m ·s) and a nozzle height of 17 mm. It is found that the heat transfer is obviously enhanced for straight fin surfaces relative to the flat surface. However, the increment decreases as the fin height increases. For flat surface and enhanced surfaces with a fin height of 0.1 mm and 0.2 mm, as the coolant flux increases, the heat flux increases as well. However, for finned surface with a height of 0.4 mm, the heat flux is not sensitive to the coolant volumetric flux. Changed film thickness and the form of water/surface interaction due to an enhanced surface structure (different fin height) are the main reasons for changing of the local heat transfer coefficient.

关键词： spray cooling     finned surface     heat transfer    

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基于几何控制法的短线预制拼装箱梁研究

王敏,张永涛,刘景红,刘毅,黄跃

《中国工程科学》 2009年 第11卷 第11期   页码 79-81

摘要：

针对短线预制拼装箱梁几何控制过程中制造及安装阶段的误差控制问题，在分析了误差产生原因的基础上，结合苏通大桥B2标的现场实际情况，介绍以几何控制理论为基础，参数敏感性分析为方法，辅以现代误差分析技术和软件开发技术，实现短线法预制拼装的全过程施工数值化管理与控制。

关键词： 几何控制     误差分析     最小二乘法     短线预制拼装    

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Edge preparation methods for cutting tools: a review

《机械工程前沿（英文）》 2023年 第18卷 第4期 doi: 10.1007/s11465-023-0766-y

摘要： Edge preparation can remove cutting edge defects, such as burrs, chippings, and grinding marks, generated in the grinding process and improve the cutting performance and service life of tools. Various edge preparation methods have been proposed for different tool matrix materials, geometries, and application requirements. This study presents a scientific and systematic review of the development of tool edge preparation technology and provides ideas for its future development. First, typical edge characterization methods, which associate the microgeometric characteristics of the cutting edge with cutting performance, are briefly introduced. Then, edge preparation methods for cutting tools, in which materials at the cutting edge area are removed to decrease defects and obtain a suitable microgeometry of the cutting edge for machining, are discussed. New edge preparation methods are explored on the basis of existing processing technologies, and the principles, advantages, and limitations of these methods are systematically summarized and analyzed. Edge preparation methods are classified into two categories: mechanical processing methods and nontraditional processing methods. These methods are compared from the aspects of edge consistency, surface quality, efficiency, processing difficulty, machining cost, and general availability. In this manner, a more intuitive understanding of the characteristics can be gained. Finally, the future development direction of tool edge preparation technology is prospected.

关键词： edge preparation method     preparation principle     cutting edge geometry     edge characterization     tool performance    

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高性能零件的性能与几何参数一体化精密加工方法与技术

郭东明

《中国工程科学》 2011年 第13卷 第10期   页码 47-57

摘要：

随着高端装备和产品的不断发展，对装备和产品制造的性能要求也越来越多和越来越高，涌现出一大批高性能指标要求的关键零部件，其加工已由以往的单纯几何形状和尺寸精度要求，跃升为以性能要求为主、性能与几何参数一体化的精密加工要求。这些高性能零件多呈精密复杂曲面、超高精度，以及材料超硬、超脆、超黏等难加工特征，其性能受几何、材料等多因素耦合作用，采用传统工艺进行精密加工制造十分困难，存在废品率高、加工效率低，特别是性能指标难以保证等难题。从高端制造装备业的需求出发，提出并阐明了高性能零件的特点、分类以及数字化可控去除加工方式的内涵，在此基础上指出了四类高性能零件精密加工所涉及的关键问题，并着重介绍了这些问题的研究现状、存在的难点和可行的解决方案，为面向高性能要求的性能与几何参数一体化的加工理论、方法和工艺技术体系的建立提供参考，以解决高性能零件的精密制造难题。

关键词： 高性能     性能与几何参数一体化     精密加工     难加工材料     复杂曲面    

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Effects of rotor and stator geometry on dissolution process and power consumption in jet-flow high shear

Lin Yang, Wenpeng Li, Junheng Guo, Wei Li, Baoguo Wang, Minqing Zhang, Jinli Zhang

《化学科学与工程前沿（英文）》 2021年 第15卷 第2期   页码 384-398 doi: 10.1007/s11705-020-1928-7

摘要： The jet-flow high shear mixer (JF-HSM) is a new type of intensified equipment with special configurations of the rotor and the stator. The mass transfer property and power consumption were studied in the solid-liquid system for a series of JF-HSMs involving different configuration parameters, such as rotor diameter, rotor blade inclination, rotor blade bending direction, stator diameter, and stator bottom opening diameter. The flow characteristics were examined by computational fluid dynamic simulations. Results indicate that the turbulent power consumption of the JF-HSM is affected by the change in rotor blade inclination and stator bottom opening. With the increase in the shear head size and the change in the rotor into a backward-curved blade, the solid-liquid mass transfer rate can be remarkably increased under the same input power. Dimensionless correlations for the mass transfer coefficient and power consumption were obtained to guide the scale-up design and selection of such a new type of equipment to intensify the overall mixing efficiency.

关键词： jet-flow high shear mixer     solid particle dissolution     power consumption characteristics     CFD Simulation    

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基于单幅微距图像的布料丝线结构建模 Special Feature on Virtual Reality-Research Articl

Hong-yu WU, Xiao-wu CHEN, Chen-xu ZHANG, Bin ZHOU, Qin-ping ZHAO

《信息与电子工程前沿（英文）》 2019年 第20卷 第9期   页码 1165-1174 doi: 10.1631/FITEE.1800693

摘要： 真实世界的布料具有不同的微观丝线结构，导致不同布料具有各种各样外观。布料真实感绘制在影视制作、电子商务等领域具有重要应用价值。为获取布料微观丝线几何信息，传统方法需要微米CT扫描仪等昂贵复杂设备，并且采集过程费时费力，难以普及。为降低布料丝线获取复杂度，本文提出一种基于单幅微距图像的丝线获取与建模方法，仅需装有微距镜头的普通消费级相机拍摄的微距图像。该方法首先通过单幅微距图像的明暗信息获得丝线的大尺度几何；然后，通过丝线追踪算法获得丝线上的纤维细节；最后将这两者结合，得到布料丝线的微观尺度几何。实验结果表明，本方法能够高效获取各种类型布料丝线几何。

关键词： 单幅微距图像；丝线三维几何；布料外观    

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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    

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考虑垫片形状和尺寸效应的珊瑚混凝土劈裂抗拉性能的三维细观研究 Article

吴彰钰, 张锦华, 余红发, 方秦, 麻海燕, 陈力

《工程（英文）》 2022年 第17卷 第10期   页码 110-122 doi: 10.1016/j.eng.2021.02.024

摘要：

珊瑚混凝土（CAC）作为一种新型建筑材料，已经在岛礁工程结构建设领域引起了极大的关注。为了研究CAC的静态劈裂抗拉性能，本文提出了一种考虑骨料形状和空间分布随机性的三维（3D）随机混凝土细观模型，影响因素包括试件形状和支承垫片尺寸。我们建立了12 个不同的混凝土细观模型，按照试件形状可分为两种，即边长为150 mm的立方体和尺寸为ϕ150 mm×300 mm的圆柱体。其中，支承垫片宽度为6 mm、9 mm、12 mm、15 mm、18 mm和20 mm。本文系统分析和讨论了试件几何形状和垫片宽度对CAC劈裂抗拉性能的影响规律，研究内容包括混凝土开裂过程、最终破坏模式和劈裂抗拉强度（fst）。结果表明：本文所开发的细观模型具有很高的可靠性，并确定了适用于CAC劈裂抗拉性能模拟和预测的最优计算参数。CAC的fst值与试件形状和垫片宽度直接相关。其中，在垫片尺寸相同的情况下，立方体CAC试件的fst值要略高于圆柱体模型，表明可以采用断裂面积的差异来解释试件形状效应对CAC fst值的影响规律。此外，当垫片的相对宽度由0.04 增加到0.13 时，CAC的fst值会呈现逐渐增大的趋势。基于弹性力学理论，本文初步确定了不同垫片宽度条件下CAC fst的取值范围，这对于研究CAC的抗拉性能具有重要意义。

关键词： 珊瑚混凝土     三维细观模拟     劈拉试验     抗拉强度     试件形状     支承垫片    

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Numerical investigation of circle defining curve for two-dimensional problem with general boundaries using the scaled boundary finite element method

Chung Nguyen VAN

《结构与土木工程前沿（英文）》 2019年 第13卷 第1期   页码 92-102 doi: 10.1007/s11709-018-0472-8

摘要： The scaled boundary finite element method (SBFEM) is applied to the static analysis of two dimensional elasticity problem, boundary value problems domain with the domain completely described by a circular defining curve. The scaled boundary finite element equations is formulated within a general framework integrating the influence of the distributed body force, general boundary conditions, and bounded and unbounded domain. This paper investigates the possibility of using exact geometry to form the exact description of the circular defining curve and the standard finite element shape function to approximate the defining curve. Three linear elasticity problems are presented to verify the proposed method with the analytical solution. Numerical examples show the accuracy and efficiency of the proposed method, and the performance is found to be better than using standard linear element for the approximation defining curve on the scaled boundary method.

关键词： exact geometry     circular defining curve     general boundaries     SBFEM    

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Optimization of Venturi tube design for pipeline pulverized coal flow measurements

WU Zhansong, XIE Fei

《能源前沿（英文）》 2008年 第2卷 第4期   页码 369-373 doi: 10.1007/s11708-008-0072-8

摘要： A Venturi flow meter was designed to accurately measure the mass flow rate of pulverized coal in power plant pipelines. Numerical simulations of the dilute turbulent gas-solid two-phase flow in a horizontal Venturi tube were used to study the effects of Venturi tube geometry on the pressure distribution in the mixture. The results show that Venturi tube geometry strongly influences the metering of the dilute gas-particle two-phase flow. The geometry can be optimized to improve the precision of the measurement and ensure stable measurements. Furthermore, the geometries of three types of Venturi tubes were optimized for an experimental study of pulverized coal mass flow rate measurements.

关键词： gas-solid two-phase     geometry     gas-particle two-phase     Numerical     flow    

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标题 作者 时间 类型 操作

Russian school of the theory and geometry of gearing: Its origin and golden period (1935 --1975)

Dmitry BABICHEV,Sergey LAGUTIN,Natalya BARMINA

期刊论文

A new proof of Honeycomb Conjecture by fractal geometry methods

Tong ZHANG, Kai DING

期刊论文

Transmission probability method based on triangle meshes for solving the unstructured geometry neutron

WU Hongchun, LIU Pingping, ZHOU Yongqiang, CAO Liangzhi

期刊论文

Experimental studies of ash film fractions based on measurement of cenospheres geometry in pulverized

Siqi LIU, Yanqing NIU, Liping WEN, Yang LIANG, Bokang YAN, Denghui WANG, Shi’en HUI

期刊论文

特大跨度斜拉桥施工几何控制原理的数值验证

黄灿,卜一之,张清华

期刊论文

Experimental study of the effects of structured surface geometry on water spray cooling performance in

Minghou LIU, Yaqing WANG, Dong LIU, Kan XU, Yiliang CHEN

期刊论文

基于几何控制法的短线预制拼装箱梁研究

王敏,张永涛,刘景红,刘毅,黄跃

期刊论文

Edge preparation methods for cutting tools: a review

期刊论文

高性能零件的性能与几何参数一体化精密加工方法与技术

郭东明

期刊论文

Effects of rotor and stator geometry on dissolution process and power consumption in jet-flow high shear

Lin Yang, Wenpeng Li, Junheng Guo, Wei Li, Baoguo Wang, Minqing Zhang, Jinli Zhang

期刊论文

基于单幅微距图像的布料丝线结构建模

Hong-yu WU, Xiao-wu CHEN, Chen-xu ZHANG, Bin ZHOU, Qin-ping ZHAO

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

考虑垫片形状和尺寸效应的珊瑚混凝土劈裂抗拉性能的三维细观研究

吴彰钰, 张锦华, 余红发, 方秦, 麻海燕, 陈力

期刊论文

Numerical investigation of circle defining curve for two-dimensional problem with general boundaries using the scaled boundary finite element method

Chung Nguyen VAN

期刊论文

Optimization of Venturi tube design for pipeline pulverized coal flow measurements

WU Zhansong, XIE Fei

期刊论文