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Simulation of cottonseed cake melt flow in metering zone of a single screw extruder
Hong HE, Jianguo ZHOU,
《化学科学与工程前沿(英文)》 2010年 第4卷 第3期 页码 263-269 doi: 10.1007/s11705-009-0276-4
关键词: quasi-three-dimensional rheological viscosity processing influence
Utilizing melt crystallization fundamentals in the development of a new tabletting technology
Ahmed ABOUZEID,Sandra PETERSEN,Joachim ULRICH
《化学科学与工程前沿(英文)》 2014年 第8卷 第3期 页码 346-352 doi: 10.1007/s11705-014-1443-9
关键词: phase separation melt crystallization tablets process optimization
Three-dimensional numerical simulation for plastic injection-compression molding
Yun ZHANG, Wenjie YU, Junjie LIANG, Jianlin LANG, Dequn LI
《机械工程前沿(英文)》 2018年 第13卷 第1期 页码 74-84 doi: 10.1007/s11465-018-0490-1
Compared with conventional injection molding, injection-compression molding can mold optical parts with higher precision and lower flow residual stress. However, the melt flow process in a closed cavity becomes more complex because of the moving cavity boundary during compression and the nonlinear problems caused by non-Newtonian polymer melt. In this study, a 3D simulation method was developed for injection-compression molding. In this method, arbitrary Lagrangian-Eulerian was introduced to model the moving-boundary flow problem in the compression stage. The non-Newtonian characteristics and compressibility of the polymer melt were considered. The melt flow and pressure distribution in the cavity were investigated by using the proposed simulation method and compared with those of injection molding. Results reveal that the fountain flow effect becomes significant when the cavity thickness increases during compression. The back flow also plays an important role in the flow pattern and redistribution of cavity pressure. The discrepancy in pressures at different points along the flow path is complicated rather than monotonically decreased in injection molding.
关键词: injection-compression molding simulation injection molding melt flow cavity pressure
Xiaobin JIANG, Baohong HOU, Yongli WANG, Jingkang WANG
《化学科学与工程前沿(英文)》 2011年 第5卷 第4期 页码 435-441 doi: 10.1007/s11705-011-1139-3
关键词: melt crystallization porous media fractal permeability hyperpure material simulation
Motoi YAMASHITA
《化学科学与工程前沿(英文)》 2009年 第3卷 第2期 页码 125-134 doi: 10.1007/s11705-009-0001-3
关键词:
Motoi YAMASHITA
《化学科学与工程前沿(英文)》 2009年 第3卷 第1期 页码 26-32 doi: 10.1007/s11705-009-0002-2
关键词: isotactic polybutene-1 tetragonal phase crystal thickness melt growth chain folding small angle X-ray scattering nucleation theory end surface free energy
压水堆熔融物堆内滞留策略:历史回顾与研究展望 Review
马卫民,元一单,Bal Raj Sehgal
《工程(英文)》 2016年 第2卷 第1期 页码 103-111 doi: 10.1016/J.ENG.2016.01.019
本文对广泛应用于第三代压水堆的严重事故缓解措施——熔融物堆内滞留(IVR)进行了历史回顾。IVR策略最早源自于第二代反应堆Lovissa VVER-440的改进设计,以应对堆芯熔化事故。随后,IVR策略被应用于许多新设计的反应堆,如西屋的AP1000、韩国的APR1400以及中国的先进压水堆CAP1400和华龙一号。对IVR策略有效性影响最大的因素分别为堆内堆芯熔化进程、熔融物加载于压力容器壁面的热流密度和压力容器外部冷却。对于堆芯熔化进程,过去人们一直仅关注压力容器下腔室内熔池的换热行为。但通过回顾与分析,本文认为堆内的其他现象,如堆芯的降级和迁移、碎片床的形成及其可冷却性以及熔池的动态形成过程等,可能也会对熔池的最终状态及其作用于下封头的热负荷产生影响。通过对相关研究的回顾,本文希望找出IVR策略的研究中有待完善的部分,并据目前发展水平提出未来IVR研究的需求。
Premature melt solidification during mold filling and its influence on the as-cast structure
M. WU, M. AHMADEIN, A. LUDWIG
《机械工程前沿(英文)》 2018年 第13卷 第1期 页码 53-65 doi: 10.1007/s11465-017-0437-y
Premature melt solidification is the solidification of a melt during mold filling. In this study, a numerical model is used to analyze the influence of the pouring process on the premature solidification. The numerical model considers three phases, namely, air, melt, and equiaxed crystals. The crystals are assumed to have originated from the heterogeneous nucleation in the undercooled melt resulting from the first contact of the melt with the cold mold during pouring. The transport of the crystals by the melt flow, in accordance with the so-called “big bang” theory, is considered. The crystals are assumed globular in morphology and capable of growing according to the local constitutional undercooling. These crystals can also be remelted by mixing with the superheated melt. As the modeling results, the evolutionary trends of the number density of the crystals and the volume fraction of the solid crystals in the melt during pouring are presented. The calculated number density of the crystals and the volume fraction of the solid crystals in the melt at the end of pouring are used as the initial conditions for the subsequent solidification simulation of the evolution of the as-cast structure. A five-phase volume-average model for mixed columnar-equiaxed solidification is used for the solidification simulation. An improved agreement between the simulation and experimental results is achieved by considering the effect of premature melt solidification during mold filling. Finally, the influences of pouring parameters, namely, pouring temperature, initial mold temperature, and pouring rate, on the premature melt solidification are discussed.
关键词: premature solidification mold filling as-cast structure modeling
Dongming QI, Xiaoli ZHAO, Zhijie CHEN, Peng HUANG, Jun CAO
《化学科学与工程前沿(英文)》 2012年 第6卷 第4期 页码 395-402 doi: 10.1007/s11705-012-1269-2
关键词: dispersion rigid organic filler isotactic polypropylene mixing
density measurement for plastic injection molding via ultrasonic technology
《机械工程前沿(英文)》 2022年 第17卷 第4期 doi: 10.1007/s11465-022-0714-2
关键词: ultrasonic measurement melt density in-situ measurement injection molding
Development of lunar regolith-based composite for - 3D printing via high-pressure extrusion system
《机械工程前沿(英文)》 2023年 第18卷 第2期 doi: 10.1007/s11465-022-0745-8
关键词: in-situ resource utilization melt extrusion molding lunar regolith-based composites mechanical properties additive manufacturing
Numerical study of internal flow field and flow passage improvement of an inlet particle separator
Florian PAOLI, Tong WANG
《能源前沿(英文)》 2011年 第5卷 第4期 页码 386-397 doi: 10.1007/s11708-011-0156-8
关键词: streamlines pressure losses flow passage improvement inlet particle separator (IPS)
Polydimethylsiloxane assisted supercritical CO
Weixia Wang, Shuai Zhou, Zhong Xin, Yaoqi Shi, Shicheng Zhao
《化学科学与工程前沿(英文)》 2016年 第10卷 第3期 页码 396-404 doi: 10.1007/s11705-016-1577-z
关键词: high melt strength polypropylene (HMSPP) polydimethylsiloxane (PDMS) supercritical CO2 foaming behavior
陆钟武
《中国工程科学》 2006年 第8卷 第1期 页码 18-25
流动,是物质(如铜、铝等)流动和流体流动二者所具有的基本特征,基于这个论点,简要地回顾了流体力学中研究流体流动的两种方法,即拉格朗日法和欧拉法;相应地提出了物质流分析的两种方法,即跟踪观察法和定点观察法。由于前者在文献中未见报道,因此对它进行了重点说明。强调了物质流的跟踪观察法既适用于稳态物质流(产品产量不变),也适用于非稳态物质流(产品产量增长或下降)。以钢铁产品生命周期的铁流图为例,说明了物质流的跟踪模型。在引入了物质流的非稳度后,提出了物质流各项指标的计算式,以及它们之间的相互关系。以瑞典铅酸电池系统为对象,计算了其中铅流的各项指标,并进行了必要的分析。
UPFC setting to avoid active power flow loop considering wind power uncertainty
Shenghu LI, Ting WANG
《能源前沿(英文)》 2023年 第17卷 第1期 页码 165-175 doi: 10.1007/s11708-020-0686-z
关键词: active power loop flow (APLF) unified power flow controller (UPFC) wind power uncertainty interval power flow (IPF)
标题 作者 时间 类型 操作
Simulation of cottonseed cake melt flow in metering zone of a single screw extruder
Hong HE, Jianguo ZHOU,
期刊论文
Utilizing melt crystallization fundamentals in the development of a new tabletting technology
Ahmed ABOUZEID,Sandra PETERSEN,Joachim ULRICH
期刊论文
Three-dimensional numerical simulation for plastic injection-compression molding
Yun ZHANG, Wenjie YU, Junjie LIANG, Jianlin LANG, Dequn LI
期刊论文
Permeability analysis and seepage process study on crystal layer in melt crystallization with fractal
Xiaobin JIANG, Baohong HOU, Yongli WANG, Jingkang WANG
期刊论文
Kinetic roughening transition and missing regime transition of melt crystallized polybutene-1 tetragonal
Motoi YAMASHITA
期刊论文
Lamellar thickness transition of melt-crystallized polybuten-1 tetragonal phase: configurational change
Motoi YAMASHITA
期刊论文
Premature melt solidification during mold filling and its influence on the as-cast structure
M. WU, M. AHMADEIN, A. LUDWIG
期刊论文
Dispersion of a novel phenolic rigid organic filler in isotactic polypropylene matrix by solution-mixing and melt-mixing
Dongming QI, Xiaoli ZHAO, Zhijie CHEN, Peng HUANG, Jun CAO
期刊论文
Development of lunar regolith-based composite for - 3D printing via high-pressure extrusion system
期刊论文
Numerical study of internal flow field and flow passage improvement of an inlet particle separator
Florian PAOLI, Tong WANG
期刊论文
Polydimethylsiloxane assisted supercritical CO
Weixia Wang, Shuai Zhou, Zhong Xin, Yaoqi Shi, Shicheng Zhao
期刊论文