检索范围:
排序: 展示方式:
Enhancing fatigue life of cylinder-crown integrated structure by optimizing dimension
Weiwei ZHANG,Xiaosong WANG,Zhongren WANG,Shijian YUAN
《机械工程前沿(英文)》 2015年 第10卷 第1期 页码 102-110 doi: 10.1007/s11465-015-0329-y
Cylinder-crown integrated hydraulic press (CCIHP) is a new press structure. The hemispherical hydraulic cylinder also functions as a main portion of crown, which has lower weight and higher section modulus compared with the conventional hydraulic cylinder and press crown. As a result, the material strength capacity is better utilized. During the engineering design of cylinder-crown integrated structure, in order to increase the fatigue life, structural optimization on the basis of the adaptive macro genetic algorithms (AMGA) is first conducted to both reduce weight and decrease peak stress. It is shown that the magnitude of the maximum principal stress is decreased by 28.6%, and simultaneously the total weight is reduced by 4.4%. Subsequently, strain-controlled fatigue test is carried out, and the stress-strain hysteresis loops and cyclic hardening curve are obtained. Based on linear fit, the fatigue properties are calculated and used for the fatigue life prediction. It is shown that the predicted fatigue life is significantly increased from 157000 to 1070000 cycles after structural optimization. Finally, according to the optimization design, a 6300 kN CCIHP has been manufactured, and priority application has been also suggested.
关键词: cylinder-crown integrated hydraulic press (CCIHP) adaptive macro genetic algorithms (AMGA) strain-controlled fatigue test
Hydraulic fracturing pressure of concentric double-layered cylinder in cohesive soil
《结构与土木工程前沿(英文)》 2021年 第15卷 第4期 页码 937-947 doi: 10.1007/s11709-021-0754-4
关键词: hydraulic fracturing pressure layered cavity expansion theory triaxial fracturing test cohesive soil
龚进,谭青,赵喻明,衡保利
《中国工程科学》 2011年 第13卷 第3期 页码 71-76
针对现有油缸检测系统检测手段和技术落后及检测精度低等缺点,提出把测试项目模块化后,将模块有机组织在液压缸运行过程中来完成油缸检测的控制策略。运用PLC(programmable logic controller,可编程控制器)控制、CoDeSys组态软件和Visual Basic 6.0技术设计了一套油缸实时检测系统。试验结果表明,新的测试系统实现了实时检测、试验数据和曲线以及试验报告的输出和打印,提高了检测效率。
Integrated virtual-design methods for forecasting radiated noise of single cylinder diesel block
GUO Lei, HAO Zhiyong, XU Hongmei, LIU Lianyun
《能源前沿(英文)》 2008年 第2卷 第4期 页码 416-421 doi: 10.1007/s11708-008-0097-z
关键词: bearing dynamical frequency response dynamical simulation hybrid dynamical
A pneumatic cylinder driving polyhedron mobile mechanism
Wan DING, Sung-Chan KIM, Yan-An YAO
《机械工程前沿(英文)》 2012年 第7卷 第1期 页码 55-65 doi: 10.1007/s11465-012-0301-z
A novel pneumatic cylinder driving polyhedron mobile mechanism is proposed in this paper. The mechanism is comprised of 5 tetrahedrons which includes a pneumatic cylinder in each edge. It locomotes by rolling and the rolling principle refers to the center of mass (CM) of the mechanism moved out of the supporting area and let it tip over through the controlling of the motion sequence of these cylinders. Firstly, the mathematical model is built to analysis the relation between the configuration and the CM of the mechanism. Then, a binary control strategy is developed to simplify and improve the control of this mobile mechanism. After that, dynamic simulation is performed to testify the analytical validity and feasibility of the rolling gaits. At last, a prototype is fabricated to achieve the rolling successfully to demonstrate the proposed concept.
PRESS-based EFOR algorithm for the dynamic parametrical modeling of nonlinear MDOF systems
Haopeng LIU, Yunpeng ZHU, Zhong LUO, Qingkai HAN
《机械工程前沿(英文)》 2018年 第13卷 第3期 页码 390-400 doi: 10.1007/s11465-017-0459-5
In response to the identification problem concerning multi-degree of freedom (MDOF) nonlinear systems, this study presents the extended forward orthogonal regression (EFOR) based on predicted residual sums of squares (PRESS) to construct a nonlinear dynamic parametrical model. The proposed parametrical model is based on the non-linear autoregressive with exogenous inputs (NARX) model and aims to explicitly reveal the physical design parameters of the system. The PRESS-based EFOR algorithm is proposed to identify such a model for MDOF systems. By using the algorithm, we built a common-structured model based on the fundamental concept of evaluating its generalization capability through cross-validation. The resulting model aims to prevent over-fitting with poor generalization performance caused by the average error reduction ratio (AERR)-based EFOR algorithm. Then, a functional relationship is established between the coefficients of the terms and the design parameters of the unified model. Moreover, a 5-DOF nonlinear system is taken as a case to illustrate the modeling of the proposed algorithm. Finally, a dynamic parametrical model of a cantilever beam is constructed from experimental data. Results indicate that the dynamic parametrical model of nonlinear systems, which depends on the PRESS-based EFOR, can accurately predict the output response, thus providing a theoretical basis for the optimal design of modeling methods for MDOF nonlinear systems.
关键词: MDOF dynamic parametrical model NARX model PRESS-based EFOR cantilever beam
喻军,刘松玉,龚晓南
《中国工程科学》 2013年 第15卷 第10期 页码 97-102
某卵砾石地层浅埋公路隧道施工开挖,围岩的稳定性与拱顶沉降存在密切的关系,因此采用仿真分析法以拱顶沉降为控制目标,确保围岩的稳定,分析不同的施工方案得到拱顶沉降规律,达到优化施工的目的;同时,分析了不同的开挖路径和台阶长度,提出了一种最佳的施工方案。结果表明:在浅埋隧道开挖时容易引起拱顶沉降,并且随着施工方案的不同,拱顶沉降有较大的差异。在几种施工方法中,发现CRD法(交叉中隔墙法)比较适合,原因是拱顶沉降最小,应力释放较慢,在渐近的过程中有效地实现了应力的转移,较台阶法和CD法(中隔墙法)有大的优势,并与现场监测进行了对比分析,结果较为吻合。得到的结论可为类似工程提供参考。
Crown ether-thiourea conjugates as ion transporters
Zhixing Zhao, Bailing Tang, Xiaosheng Yan, Xin Wu, Zhao Li, Philip A. Gale, Yun-Bao Jiang
《化学科学与工程前沿(英文)》 2022年 第16卷 第1期 页码 81-91 doi: 10.1007/s11705-021-2049-7
Convective mass transfer from a horizontal rotating cylinder in a slot air jet flow
Hongting MA , Dandan MA , Na YANG ,
《能源前沿(英文)》 2009年 第3卷 第3期 页码 289-296 doi: 10.1007/s11708-009-0019-8
关键词: air jet impinging rotating cylinder critical point mass transfer characteristics
CHEN Changfu, XIAO Shujun, YANG Yu
《结构与土木工程前沿(英文)》 2007年 第1卷 第3期 页码 329-333 doi: 10.1007/s11709-007-0043-x
Baosheng ZHAO, Yang GAO, Yingtao ZHAO, Dechen ZHANG
《机械工程前沿(英文)》 2011年 第6卷 第3期 页码 318-323 doi: 10.1007/s11465-011-0232-0
The refined theory for axi-symmetric magnetoelastic circular cylinder is deduced systematically and directly from linear magnetoelasticity theory. Based on the general solution of magnetoelastic equation and the Lur’e method, the refined theory yields the solutions for magnetoelastic circular cylinder without ad hoc assumptions. On the basis of the refined theory developed in the present study, solutions are obtained for magnetoelastic circular cylinder with homogeneous and non-homogenous boundary conditions, respectively. For the circular cylinder with homogeneous boundary conditions, the refined theory provides exact solutions that satisfy all of the governing equations. The exact solutions can be divided into three parts: the 2-orders equation, the transcendental equation, and the magnetic equation. In the case of non-homogenous boundary conditions, the approximate governing equations are accurate up to the high-order terms with respect to cylinder radius.
关键词: refined analysis axially symmetric deformation circular cylinder Bessel’s function axial magnetic field
Jizu LV, Minli BAI, Long ZHOU, Jian ZHOU,
《能源前沿(英文)》 2010年 第4卷 第3期 页码 392-401 doi: 10.1007/s11708-009-0066-1
关键词: heat transfer space non-uniformity soot emission in-cylinder diesel
Combustion and emissions of RP-3 jet fuel and diesel fuel in a single-cylinder diesel engine
《能源前沿(英文)》 2023年 第17卷 第5期 页码 664-677 doi: 10.1007/s11708-021-0787-3
Multiobjective trajectory optimization of intelligent electro-hydraulic shovel
《机械工程前沿(英文)》 2022年 第17卷 第4期 doi: 10.1007/s11465-022-0706-2
关键词: trajectory planning electro-hydraulic shovel cubic polynomial S-curve multiobjective optimization entropy weight technique
Wenchi GONG, Jun SHEN, Wei DAI, Zeng DENG, Xueqiang DONG, Maoqiong GONG
《能源前沿(英文)》 2020年 第14卷 第1期 页码 127-138 doi: 10.1007/s11708-020-0661-8
关键词: laminar flow hydraulic entrance length super hydrophobic surface slip length hydraulic diameter
标题 作者 时间 类型 操作
Enhancing fatigue life of cylinder-crown integrated structure by optimizing dimension
Weiwei ZHANG,Xiaosong WANG,Zhongren WANG,Shijian YUAN
期刊论文
Integrated virtual-design methods for forecasting radiated noise of single cylinder diesel block
GUO Lei, HAO Zhiyong, XU Hongmei, LIU Lianyun
期刊论文
PRESS-based EFOR algorithm for the dynamic parametrical modeling of nonlinear MDOF systems
Haopeng LIU, Yunpeng ZHU, Zhong LUO, Qingkai HAN
期刊论文
Crown ether-thiourea conjugates as ion transporters
Zhixing Zhao, Bailing Tang, Xiaosheng Yan, Xin Wu, Zhao Li, Philip A. Gale, Yun-Bao Jiang
期刊论文
Convective mass transfer from a horizontal rotating cylinder in a slot air jet flow
Hongting MA , Dandan MA , Na YANG ,
期刊论文
Unified solution of limit loads of thick wall cylinder subject to external pressure considering strain
CHEN Changfu, XIAO Shujun, YANG Yu
期刊论文
Refined analysis of axi-symmetric circular cylinder in the axial magnetic field without ad hoc assumption
Baosheng ZHAO, Yang GAO, Yingtao ZHAO, Dechen ZHANG
期刊论文
Effect of heat transfer space non-uniformity of combustion chamber components on in-cylinder heat transfer
Jizu LV, Minli BAI, Long ZHOU, Jian ZHOU,
期刊论文