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Robust isogeometric topology optimization for piezoelectric actuators with uniform manufacturability
《机械工程前沿(英文)》 2022年 第17卷 第2期 doi: 10.1007/s11465-022-0683-5
关键词: piezoelectric actuator isogeometric topology optimization uniform manufacturability robust formulation density distribution function
Shutian LIU,Quhao LI,Wenjiong CHEN,Liyong TONG,Gengdong CHENG
《机械工程前沿(英文)》 2015年 第10卷 第2期 页码 126-137 doi: 10.1007/s11465-015-0340-3
Additive manufacturing (AM) technologies, such as selective laser sintering (SLS) and fused deposition modeling (FDM), have become the powerful tools for direct manufacturing of complex parts. This breakthrough in manufacturing technology makes the fabrication of new geometrical features and multiple materials possible. Past researches on designs and design methods often focused on how to obtain desired functional performance of the structures or parts, specific manufacturing capabilities as well as manufacturing constraints of AM were neglected. However, the inherent constraints in AM processes should be taken into account in design process. In this paper, the enclosed voids, one type of manufacturing constraints of AM, are investigated. In mathematics, enclosed voids restriction expressed as the solid structure is simply-connected. We propose an equivalent description of simply-connected constraint for avoiding enclosed voids in structures, named as virtual temperature method (VTM). In this method, suppose that the voids in structure are filled with a virtual heating material with high heat conductivity and solid areas are filled with another virtual material with low heat conductivity. Once the enclosed voids exist in structure, the maximum temperature value of structure will be very high. Based upon this method, the simply-connected constraint is equivalent to maximum temperature constraint. And this method can be easily used to formulate the simply-connected constraint in topology optimization. The effectiveness of this description method is illustrated by several examples. Based upon topology optimization, an example of 3D cantilever beam is used to illustrate the trade-off between manufacturability and functionality. Moreover, the three optimized structures are fabricated by FDM technology to indicate further the necessity of considering the simply-connected constraint in design phase for AM.
关键词: additive manufacturing topology optimization manufacturability constraints design for additive manufacturing simply-connected constraint
Assessment indices for uniform and non-uniform thermal environments
ZHANG Yufeng, SUN Shufeng, ZHAO Rongyi
《能源前沿(英文)》 2008年 第2卷 第2期 页码 129-133 doi: 10.1007/s11708-008-0029-y
关键词: thermal sensation proper assessment relationship equivalent thermal acceptability
Effect of non-uniform illumination on performance of solar thermoelectric generators
Ershuai YIN, Qiang LI, Yimin XUAN
《能源前沿(英文)》 2018年 第12卷 第2期 页码 239-248 doi: 10.1007/s11708-018-0533-7
关键词: solar thermoelectric generators non-uniform solar illumination performance evaluation solar energy
Nodal, zonal, or uniform electricity pricing: how to deal with network congestion
Martin WEIBELZAHL
《能源前沿(英文)》 2017年 第11卷 第2期 页码 210-232 doi: 10.1007/s11708-017-0460-z
关键词: nodal pricing zonal pricing uniform pricing competitive electricity markets welfare maximization redispatch optimization models
XU Jian, LIU Weijun, LIU Honglai, HU Ying
《化学科学与工程前沿(英文)》 2007年 第1卷 第3期 页码 221-227 doi: 10.1007/s11705-007-0040-6
关键词: solution-phase photoelectron spectroscopy 16-3-16 surfactant transmission
Peiwen Liu, Carsten Mai, Kai Zhang
《化学科学与工程前沿(英文)》 2018年 第12卷 第3期 页码 383-389 doi: 10.1007/s11705-018-1718-7
Hydrogels with precisely designed structures represent promising materials with a broad application spectrum, such as for sensor, tissue engineering and biomimetic technology. However, with highly reactive compounds, the preparation of hydrogels still needs an efficient approach for desired distribution of each component within hydrogels. In addition, a method for in situ preparation of gradient hydrogels is still lacking. Herein, we report the formation of hydrogels with either uniform or gradient internal structures via a novel, simple but very efficient method by aerating ammonia gas (NH3 gas) into the solution of dialdehyde cellulose (DAC) and a diamine. As-prepared hydrogels exhibited uniform microscopic and chemical structure or gradient distribution of functional groups. Due to lots of aldehyde groups on DAC chains, functional hydrogels can be prepared by using diverse diamines. For instance, hydrogels prepared by using 1,6-hexanediamine as a cross-linker were responsive to pH values. Moreover, this controllable process of aerating NH3 gas allows the in situ formation of gradient hydrogels; for instance, by using cyanamide as a reaction counterpart, gradient hydrogels with gradient distributions of cyanide groups were prepared.
关键词: hydrogel uniform gradient dialdehyde cellulose ammonia gas diamine
Orderly decorated nanostructural photoelectrodes with uniform spherical TiO
A. M. Bakhshayesh,S. S. Azadfar
《化学科学与工程前沿(英文)》 2015年 第9卷 第4期 页码 532-540 doi: 10.1007/s11705-015-1549-8
关键词: dye-sensitized solar cell uniform particles TiO2 gel process light harvesting
Analytical and numerical investigation into the longitudinal vibration of uniform nanotubes
null
《机械工程前沿(英文)》 2014年 第9卷 第2期 页码 142-149 doi: 10.1007/s11465-014-0292-z
In recent years, prediction of the behaviors of micro and nanostructures is going to be a matter of increasing concern considering their developments and uses in various engineering fields. Since carbon nanotubes show the specific properties such as strength and special electrical behaviors, they have become the main subject in nanotechnology researches. On the grounds that the classical continuum theory cannot accurately predict the mechanical behavior of nanostructures, nonlocal elasticity theory is used to model the nanoscaled systems. In this paper, a nonlocal model for nanorods is developed, and it is used to model the carbon nanotubes with the aim of the investigating into their longitudinal vibration. Following the derivation of governing equation of nanorods and estimation of nondimensional frequencies, the effect of nonlocal parameter and the length of the nanotube on the obtained frequencies are studied. Furthermore, differential quadrature method, as a numerical solution technique, is used to study the effect of these parameters on estimated frequencies for both classical and nonlocal theories.
关键词: continuum theory differential quadrature method nanorod longitudinal vibration
赵颜利,平萍,刘凤玉
《中国工程科学》 2008年 第10卷 第7期 页码 147-152
给出了k( k ≥ 3) 阶指数多项式的均匀样条模型。该类模型具有很多与B 样条模型相同的性质,并 且增加了一个可调节的形状参数。由该模型构造的曲线,通过改变形状参数的取值,可以调整曲线接近其控 制多边形的程度。应用于CAD/CAM领域,可作为几何造型的一种新的有效模型。
Centrifugal compressor blade optimization based on uniform design and genetic algorithms
SHU Xinwei, GU Chuangang, XIAO Jun, GAO Chuang
《能源前沿(英文)》 2008年 第2卷 第4期 页码 453-456 doi: 10.1007/s11708-008-0083-5
关键词: information computational centrifugal compressor regression analysis CFD
Hongtao WANG, Huayong WU
《环境科学与工程前沿(英文)》 2009年 第3卷 第1期 页码 112-128 doi: 10.1007/s11783-008-0067-z
关键词: solution library contaminant transport analytical solution dispersion and advection porous media type curve Green's function method (GFM)
Wei Xiong, Susu Zhou, Zeyong Zhao, Fang Hao, Zhihui Cai, Pingle Liu, Hailiang Zhang, Hean Luo
《化学科学与工程前沿(英文)》 2021年 第15卷 第4期 页码 998-1007 doi: 10.1007/s11705-020-1994-x
关键词: nitrogen and phosphorus doping non-noble nickel catalyst aromatic compounds hydrogenation
顾伟,雷威,张晓兵,杨国栋,吴永强,方庆华
《中国工程科学》 2007年 第9卷 第3期 页码 71-75
设计了圆环型的灯心结构,在期望张角处布置反射光线照度峰值的办法,得到了表达所期望镜面的一 阶二次微分方程。经过数值求解和函数拟合,确定了球冠结构的反射侧面。当在球冠下方加装圆锥型镜面之后, 进一步提高了广角内的照度均匀度。设计方案将90°张角内的照度不均匀度从设计前的65%改善到了±15%之内。
赵颜利,王湛,郭成昊,刘凤玉
《中国工程科学》 2007年 第9卷 第7期 页码 65-70
利用形参均匀B样条平滑公式,建立了一种盈亏修正的图像边缘检测新方法。首先对图像的原型值点进行盈亏修正,进一步减少原始图像和平滑图像之间的残余误差;然后利用形参均匀B样条修匀公式对修正后的图像拟合光滑曲面;最后求拟合后的光滑曲面的一阶导数极值点或二阶导数的零交叉点作为边缘特征点。试验表明,该方法稳定可靠,精度较高,能够很好地去除伪边缘;同时该方法简洁,便于实时处理。
标题 作者 时间 类型 操作
Robust isogeometric topology optimization for piezoelectric actuators with uniform manufacturability
期刊论文
An identification method for enclosed voids restriction in manufacturability design for additive manufacturing
Shutian LIU,Quhao LI,Wenjiong CHEN,Liyong TONG,Gengdong CHENG
期刊论文
Assessment indices for uniform and non-uniform thermal environments
ZHANG Yufeng, SUN Shufeng, ZHAO Rongyi
期刊论文
Effect of non-uniform illumination on performance of solar thermoelectric generators
Ershuai YIN, Qiang LI, Yimin XUAN
期刊论文
Nodal, zonal, or uniform electricity pricing: how to deal with network congestion
Martin WEIBELZAHL
期刊论文
Controlled synthesis of uniform silver nanowires with high aspect ratios in aqueous solutions of gemini
XU Jian, LIU Weijun, LIU Honglai, HU Ying
期刊论文
Preparation of hydrogels with uniform and gradient chemical structures using dialdehyde cellulose and
Peiwen Liu, Carsten Mai, Kai Zhang
期刊论文
Orderly decorated nanostructural photoelectrodes with uniform spherical TiO
A. M. Bakhshayesh,S. S. Azadfar
期刊论文
Analytical and numerical investigation into the longitudinal vibration of uniform nanotubes
null
期刊论文
Centrifugal compressor blade optimization based on uniform design and genetic algorithms
SHU Xinwei, GU Chuangang, XIAO Jun, GAO Chuang
期刊论文
Analytical solutions of three-dimensional contaminant transport in uniform flow field in porous media
Hongtao WANG, Huayong WU
期刊论文
Highly uniform Ni particles with phosphorus and adjacent defects catalyze 1,5-dinitronaphthalene hydrogenation
Wei Xiong, Susu Zhou, Zeyong Zhao, Fang Hao, Zhihui Cai, Pingle Liu, Hailiang Zhang, Hean Luo
期刊论文