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Multimodal Fuzzy Downstream Petroleum Supply Chain:A Novel Pentagonal Fuzzy Optimization
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作者 Gul Freen Sajida Kousar +2 位作者 Nasreen Kausar Dragan Pamucar Georgia Irina Oros 《Computers, Materials & Continua》 SCIE EI 2023年第3期4861-4879,共19页
The petroleum industry has a complex,inflexible and challenging supply chain(SC)that impacts both the national economy as well as people’s daily lives with a range of services,including transportation,heating,electri... The petroleum industry has a complex,inflexible and challenging supply chain(SC)that impacts both the national economy as well as people’s daily lives with a range of services,including transportation,heating,electricity,lubricants,as well as chemicals and petrochemicals.In the petroleum industry,supply chain management presents several challenges,especially in the logistics sector,that are not found in other industries.In addition,logistical challenges contribute significantly to the cost of oil.Uncertainty regarding customer demand and supply significantly affects SC networks.Hence,SC flexibility can be maintained by addressing uncertainty.On the other hand,in the real world,decision-making challenges are often ambiguous or vague.In some cases,measurements are incorrect owing to measurement errors,instrument faults,etc.,which lead to a pentagonal fuzzy number(PFN)which is the extension of a fuzzy number.Therefore,it is necessary to develop quantitative models to optimize logistics operations and supply chain networks.This study proposed a linear programming model under an uncertain environment.The model minimizes the cost along the refineries,depots,multimode transport and demand nodes.Further developed pentagonal fuzzy optimization,an alternative approach is developed to solve the downstream supply chain using themixed-integer linear programming(MILP)model to obtain a feasible solution to the fuzzy transportation cost problem.In this model,the coefficient of the transportation costs and parameters is assumed to be a pentagonal fuzzy number.Furthermore,defuzzification is performed using an accuracy function.To validate the model and technique and feasibility solution,an illustrative example of the oil and gas SC is considered,providing improved results compared with existing techniques and demonstrating its ability to benefit petroleum companies is the objective of this study. 展开更多
关键词 Downstream petroleum supply chain fuzzy optimization multimodal optimization pentagonal fuzzy number
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Hom-Hopf元(映射)与Hom-Hopf(Pentagon)方程的解 被引量:2
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作者 焦争鸣 黄功宇 《河南师范大学学报(自然科学版)》 CAS 北大核心 2016年第3期1-6,共6页
引进了Hom-Hopf(Pentagon)方程以及Hom-Hopf元(映射)等概念,讨论了这两类方程的等价性.进而证明:一个Hom-双代数(H,α)的Hom-Hopf元(或Hom-Hopf映射),可以用来构造任意左H-Hom-模(或右HHom-余模)(M,αM)上Hom-Hopf方程的解.
关键词 Hom-双代数 Hom-Hopf方程 Hom-pentagon方程 Hom-Hopf元 Hom-Hopf映射
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关于Pentagon方程与Hopf模及双代数的关系
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作者 何济位 《浙江大学学报(理学版)》 CAS CSCD 2003年第1期7-11,18,共6页
设H既是一个代数,同时又是一个余代数(不必是双代数),证明了当模HM和余模MH满足适当条件时,H为Hopf代数,并且HMH为Hopf模;在一般的情况下,若H是双代数,则可以构作H的商双代数H,使M成为H上的Hopf模.另外,从已知的双代数出发,可以构造新的... 设H既是一个代数,同时又是一个余代数(不必是双代数),证明了当模HM和余模MH满足适当条件时,H为Hopf代数,并且HMH为Hopf模;在一般的情况下,若H是双代数,则可以构作H的商双代数H,使M成为H上的Hopf模.另外,从已知的双代数出发,可以构造新的Pentagon方程的解. 展开更多
关键词 pentagon方程 HOPF模 双代数 相容性条件 余代数 商双代数
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基于空间分析理论改进的变压器Duval Pentagon1故障诊断方法 被引量:2
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作者 张丞鸣 谢菊芳 +2 位作者 余松 唐超 胡东 《高电压技术》 EI CAS CSCD 北大核心 2022年第6期2255-2264,共10页
为了解决Duval Pentagon1法不能表征各种变压器故障模式可信度的问题,提出了一种基于空间分析理论改进的方法。首先,采用核密度估计(kernel density estimation,KDE)方法对各种变压器故障模式数据进行空间分布密度分析;其次,应用B样条... 为了解决Duval Pentagon1法不能表征各种变压器故障模式可信度的问题,提出了一种基于空间分析理论改进的方法。首先,采用核密度估计(kernel density estimation,KDE)方法对各种变压器故障模式数据进行空间分布密度分析;其次,应用B样条理论构造各种变压器故障模式密度曲面;最后,利用空间叠置分析方法实现变压器故障模式识别。实例分析结果表明:与Duval Pentagon1法相比,改进后的Duval Pentagon1法的总体诊断准确率提升了8.42%,并且能够定量地表征各种变压器故障模式可信度。研究结果可为变压器油中溶解气体图形分析方法的改进提供参考。 展开更多
关键词 变压器 故障诊断 Duval pentagon1法 油中溶解气体分析 空间分析理论
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Dielectric Loading on Multi-Band Behaviors of Pentagonal Fractal Patch Antennas
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作者 Ravindra Kumar Yadav Jugul Kishor R. L. Yadava 《Open Journal of Antennas and Propagation》 2013年第3期49-56,共8页
This paper describes the multiband behaviour as well as the response for dielectric loading of a pentagonal fractal patch antenna designed at frequency f = 2.45 GHz. The proposed antenna shape has been obtained by int... This paper describes the multiband behaviour as well as the response for dielectric loading of a pentagonal fractal patch antenna designed at frequency f = 2.45 GHz. The proposed antenna shape has been obtained by introducing slots in a pentagonal patch antenna up to second iteration. Detailed design steps and results of the designs are studied and investigated in this paper. Simulated and measured results reveal that the antenna will be operated at three different frequency bands—2.17 GHz, 3.56 GHz, and 7.93 GHz with acceptable performances (i.e. VSWR < 2). The measured results for the antennas are in good agreement with simulated results. The proposed antenna maintains good radiation pattern with gain. However dielectric loading increases its radiation efficiency at the cost of significant decrease in gain and directivity. 展开更多
关键词 FRACTAL PATCH Antenna MULTIBAND pentagonal PATCH and DIELECTRIC Loading
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Evidence for pentagonal symmetry in living and model cellular systems
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作者 John J. Wille 《Natural Science》 2011年第10期866-883,共18页
Microscope observations of normal human ke- ratinocytes (NHK) propagated in a serum-free medium reveal a high frequency (>70%) of pentagonally-shaped colonies over a wide range of colony sizes that persist over man... Microscope observations of normal human ke- ratinocytes (NHK) propagated in a serum-free medium reveal a high frequency (>70%) of pentagonally-shaped colonies over a wide range of colony sizes that persist over many sequential cell generations. NHK colonies derived from sin- gle cell isolates also display pentagonal symme- try as confirmed by a photographic technique known as “Markham Rotation”. The generality of pentagonal cellular morphology was extended to observations in situ of pentagonally-shaped basal layer epidermal cells of normal human epidermis, monolayer cultures of normal and immortalized keratinocytes, several different ch- ick embryo cells, and in previously published photographs. Statistical methods were applied that differentiate planar close-packing of polygonal configurations observed in living cellular system from several examples of non-living cellular aggregates that were produced spontaneously in nature or in the laboratory under defined physico-chemical conditions. 展开更多
关键词 Cells COLONIES in VITRO Tissue Culture MAMMALIAN TISSUES MODEL TISSUES pentagonal SYMMETRY Rotational SYMMETRY Analysis
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The affection on the nature of percolation by concentration of pentagon–heptagon defects in graphene lattice
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作者 杨宇明 滕保华 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第10期508-511,共4页
In this paper the percolation behavior with a specific concentration of the defects was discussed on the twodimensional graphene lattice. The percolation threshold is determined by a numerical method with a high degre... In this paper the percolation behavior with a specific concentration of the defects was discussed on the twodimensional graphene lattice. The percolation threshold is determined by a numerical method with a high degree of accuracy. This method is also suitable for locating the percolation critical point on other crystalline structures. Through investigating the evolution of the largest cluster size and the cluster sizes distribution, we find that under various lattice sizes and concentrations of pentagon-heptagon defects there is no apparent change for the percolation properties in graphene lattice. 展开更多
关键词 五边形 过滤 格子 性质 数字方法 精确性 尺寸
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Existence and uniqueness for a class of double pyramidal central configurations with a concave pentagonal base
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作者 刘学飞 《Journal of Chongqing University》 CAS 2003年第1期28-30,共3页
Based on some necessary conditions for double pyramidal central configurations with a concave pentagonal base, for any given ratio of masses, the existence and uniqueness of a class of double pyramidal central configu... Based on some necessary conditions for double pyramidal central configurations with a concave pentagonal base, for any given ratio of masses, the existence and uniqueness of a class of double pyramidal central configurations with a concave pentagonal base in 7-body problems are proved and the range of the ratio between radius and half-height is obtained, within which the 7 bodies involved form a central configuration or form uniquely a central configuration. 展开更多
关键词 牛顿力学 N体问题 凹五边形基础 双锥体中心结构 存在性 唯一性
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不同绕组连接方式对五相电机故障后的电磁性能影响
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作者 刘文辉 艾萌萌 《防爆电机》 2024年第2期27-29,38,共4页
针对五相电动机的星形连接方式和五边形连接方式进行仿真,得出转矩、转速、气隙磁密、磁密、电磁损耗等数据,以及在缺相故障后星形连接方式和五边形连接方式产生的数据进行比对,尽可能的分析两种不同连接状态下的电磁影响。对在不同工... 针对五相电动机的星形连接方式和五边形连接方式进行仿真,得出转矩、转速、气隙磁密、磁密、电磁损耗等数据,以及在缺相故障后星形连接方式和五边形连接方式产生的数据进行比对,尽可能的分析两种不同连接状态下的电磁影响。对在不同工况下的不同连接方式所得的不同结果进行比对,得到这两种连接状态下的优缺点,并对两种连接方式在故障后的电磁影响进行分析,提出在缺相故障后的电磁区别。 展开更多
关键词 五相感应电机 星形连接 五边形连接 电磁影响 损耗计算
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Resistance Calculation of Pentagonal Lattice Structure of Resistors
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作者 M.Q.Owaidat J.H.Asad 《Communications in Theoretical Physics》 SCIE CAS CSCD 2019年第8期935-938,共4页
In this study, the effective resistance between any two lattice sites in a two-dimensional pentagonal lattice structure of identical resistors is determined by means of the lattice Green’s function method.Some numeri... In this study, the effective resistance between any two lattice sites in a two-dimensional pentagonal lattice structure of identical resistors is determined by means of the lattice Green’s function method.Some numerical results of the resistance for small separations between lattice sites are presented. 展开更多
关键词 LATTICE Green’s function pentagonal LATTICE RESISTANCE NUMERICAL RESULTS
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山西离石吉家村遗址发掘报告
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作者 张海蛟 刘吉祥 +2 位作者 刘鹤婷(绘图) 李海龙(照相) 樊娇凤 《文物季刊》 2024年第1期16-27,共12页
吉家村遗址位于山西省吕梁市离石区的东川河北岸,发现了属于仰韶时期庙底沟文化的五边形房址2座,出土遗物主要有彩陶罐、小口尖底瓶等。这是继2019年离石德岗遗址发现五边形房址后,吕梁山区又一次发现五边形房址,对研究吕梁山腹地仰韶... 吉家村遗址位于山西省吕梁市离石区的东川河北岸,发现了属于仰韶时期庙底沟文化的五边形房址2座,出土遗物主要有彩陶罐、小口尖底瓶等。这是继2019年离石德岗遗址发现五边形房址后,吕梁山区又一次发现五边形房址,对研究吕梁山腹地仰韶时期的文化内涵和发展历程具有重要意义。 展开更多
关键词 离石 吉家村 庙底沟文化 五边形房址
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Monolayer puckered pentagonal VTe_(2):An emergent two-dimensional ferromagnetic semiconductor with multiferroic coupling
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作者 Xuanyi Li Zhili Zhu +5 位作者 Qing Yang Zexian Cao Yeliang Wang Sheng Meng Jiatao Sun Hong-Jun Gao 《Nano Research》 SCIE EI CSCD 2022年第2期1486-1491,共6页
Two-dimensional(2D)magnetic crystals have been extensively explored thanks to their potential applications in spintronics,valleytronics,and topological superconductivity.Here we report a novel monolayer magnet,namely ... Two-dimensional(2D)magnetic crystals have been extensively explored thanks to their potential applications in spintronics,valleytronics,and topological superconductivity.Here we report a novel monolayer magnet,namely puckered pentagonal VTe_(2)(PP-VTe_(2)),intriguing atomic and electronic structures of which were firmly validated from first-principles calculations.The PP-VTe_(2) exhibits strong intrinsic ferromagnetism and semiconducting property distinct from the half-metallic bulk pyrite VTe_(2)(BP-VTe_(2))phase.An unusual magnetic anisotropy with large magnetic exchange energies is found.More interestingly,the multiferroic coupling between its 2D ferroelasticity and in-plane magnetization is further identified in PP-VTe_(2),lending it unprecedented controllability with external strains and electric fields.Serving as an emergent 2D ferromagnetic semiconductor with a novel crystal structure,monolayer PP-VTe_(2) provides an ideal platform for exploring exotic crystalline and spin configurations in low-dimensional systems. 展开更多
关键词 FIRST-PRINCIPLES puckered pentagonal VTe_(2) ferromagnetic semiconductor FERROELASTICITY
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Ferromagnetic coupling in a two-dimensional Cairo pentagonal Ni_(2)(TCNQ)_(2) lattice
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作者 Aizhu Wang Hongguang Wang +4 位作者 Xiaopeng Wang Na Ren Longhua Ding Xin Yu Mingwen Zhao 《Journal of Materiomics》 SCIE 2022年第3期627-632,共6页
Magnetism has revolutionized important technologies,and continues to bring forth new phenomena in emergent materials and reduced dimensions.Here,using first-principles calculations,we demonstrate that the already-synt... Magnetism has revolutionized important technologies,and continues to bring forth new phenomena in emergent materials and reduced dimensions.Here,using first-principles calculations,we demonstrate that the already-synthesized two-dimensional(2D)Ni-tetracyanoquinodimethane(Ni_(2)(TCNQ)_(2))lattice is a stable ferromagnetism material with multiple spin-polarized Dirac cones.The conical bands in proximity of the Fermi level can be tuned by external tensile strain and show the fourfold degenerate electronic states at the critical tensile strain of~2.35%,whose energy dispersion is consistent with 2D Cairo pentagonal lattice.In addition,spin-orbital coupling can open a band gap at the Dirac point of A,leading to topologically nontrivial electronic states characterized by the non-zero Chern number and the edge states of nanoribbon.Our results offer versatile platforms for the realization of massless spintronics with full-spin polarization in 2D Cairo pentagonal Ni_(2)(TCNQ)_(2) Lattice. 展开更多
关键词 First-principles calculations Ferromagnetic coupling Linear dispersion 2D Cairo pentagonal lattice Quantum anomalous Hall effect
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Pentagon Chief In China Discusses Military Hotline,Taiwan
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《Beijing Review》 2007年第46期13-13,共1页
U.S.Secretary of Defense Robert Gates visited China on November 4-6,a trip that was regarded as an important event in the exchanges between the two countries’ armed forces.
关键词 In pentagon Chief In China Discusses Military Hotline Taiwan
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Hijacked Planes Destroy Twin Towers, Burn Pentagon
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作者 Alan Elsner Arthur Spiegelman 窦宇 《当代外语研究》 2001年第10期9-13,共5页
美国东部时间2001年9月11日上午9时(北京时间9月11日21时)以后,美国纽约和华盛顿的主要建筑接连遭到恐怖主义分子袭击。下文是事件发生后9小时的报道。
关键词 Burn pentagon Hijacked Planes Destroy Twin Towers 华盛顿 内布拉斯加州
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专访芬兰Pentagon Design:重塑日常设计
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《包装与设计》 2019年第2期6-21,共16页
作为'世界设计之都',赫尔辛基优秀的设计公司数不胜数。然而如果你去芬兰,想请芬兰国家级设计中心推荐一家优秀的设计公司,那他们首先推荐的一定是Pentagon Design。Pentagon Design创立于1996年,是北欧一流的跨学科设计机构,... 作为'世界设计之都',赫尔辛基优秀的设计公司数不胜数。然而如果你去芬兰,想请芬兰国家级设计中心推荐一家优秀的设计公司,那他们首先推荐的一定是Pentagon Design。Pentagon Design创立于1996年,是北欧一流的跨学科设计机构,创始人Arni Aromaa和Sauli Suomela均为优秀的工业设计师——两人都毕业于赫尔辛基艺术与设计学院(现阿尔托大学艺术与设计学院)工业设计系并获得硕士学位. 展开更多
关键词 pentagon DESIGN 斯堪的纳维亚 赫尔辛基 巧克力 产品包装 陈列馆 工业设计师 糖果店 芬兰堡 视觉形象
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Growth of large-area aligned pentagonal graphene domains on high-index copper surfaces 被引量:2
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作者 Kailun Xia Vasilii I. Artyukhov +4 位作者 Lifei Sun Jingying Zheng Liying Jiao Boris I. Yakobson Yingying Zhang 《Nano Research》 SCIE EI CAS CSCD 2016年第7期2182-2189,共8页
化学蒸汽免职(CVD ) 内在地种的单个水晶的 graphene 领域趋于有六倍的对称;然而,几个因素能影响生长动力学,它能接着与不同形状导致 graphene 的形成。这里,我们由 CVD 在 Cu 陪衬上报导面向的大区域的五角的单个水晶的 graphene ... 化学蒸汽免职(CVD ) 内在地种的单个水晶的 graphene 领域趋于有六倍的对称;然而,几个因素能影响生长动力学,它能接着与不同形状导致 graphene 的形成。这里,我们由 CVD 在 Cu 陪衬上报导面向的大区域的五角的单个水晶的 graphene 领域的生长。我们发现那飞机有选择地贡献了到五角的 graphene 的形成的高索引的 Cu。我们的结果显示在内在的 Cu 的水晶的表面上在场的格子步在对步垂直的方向支持了 graphene 生长并且最后导致了形成一个五边形的边之一的消失。另外,氢支持了五角的领域的形成。这个工作提供新卓见进 graphene 生长的机制。 展开更多
关键词 石墨 铜箔 表面 面积 五边形 化学气相沉积 生长动力学 对齐
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质子交换膜燃料电池五边形挡板流场结构优化与性能改进 被引量:1
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作者 陈吉清 曾常菁 +2 位作者 周云郊 兰凤崇 刘青山 《汽车工程》 EI CSCD 北大核心 2023年第10期1862-1875,共14页
为有效提高燃料电池(fuel cell,FC)的性能,提出一种在阴极处具有五边形挡板的新型流场(flow field,FF)设计。为了解五边形挡板的加入对FC内部传质过程的影响,开发了一个三维、多相、非等温稳态模型,将多孔层结构引起的各向异性传输性质... 为有效提高燃料电池(fuel cell,FC)的性能,提出一种在阴极处具有五边形挡板的新型流场(flow field,FF)设计。为了解五边形挡板的加入对FC内部传质过程的影响,开发了一个三维、多相、非等温稳态模型,将多孔层结构引起的各向异性传输性质和催化层实际团聚体结构的非均质特性耦合到模型中,研究了挡板高度变化时FC性能的变化。结果表明,五边形挡板增强了流道的传质性能与气体分布均匀性。随着挡板高度增加,流道的传质性能、排水性能以及气体分布均匀性增加,高度100%(H100)的挡板由于与气体扩散层直接接触,堵塞了排水通道,因此其保水性能最好。在相对湿度为50%情况下,H100的FF结构具有最大的净功率密度,与原始FF(H0)相比,净功率密度增加17.778%。 展开更多
关键词 质子交换膜燃料电池 五边形挡板 挡板高度 各向异性 催化层团聚体模型 非等温
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单点渐进成形工艺参数对正五边锥形件壁厚的影响 被引量:1
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作者 安治国 田维杰 +2 位作者 门正兴 叶了 高正源 《精密成形工程》 北大核心 2023年第1期41-50,共10页
目的 利用数值模拟方法研究单点渐进成形工艺参数对制件成形区最小壁厚的影响规律,得出最优工艺参数组合,提高制件的成形质量。方法 在对2024铝合金正五边锥形件建立有模单点渐进成形数值仿真模型的基础上,对进给率、层间距、成形工具... 目的 利用数值模拟方法研究单点渐进成形工艺参数对制件成形区最小壁厚的影响规律,得出最优工艺参数组合,提高制件的成形质量。方法 在对2024铝合金正五边锥形件建立有模单点渐进成形数值仿真模型的基础上,对进给率、层间距、成形工具头直径和摩擦因数对制件成形区最小壁厚的影响进行单因素和正交试验分析,并通过物理试验对仿真优化后的工艺参数组合进行验证。结果 正五边锥形件单点渐进成形加工过程中,最小壁厚与进给率、层间距成反比,与成形工具头直径成正比,而摩擦因数对最小壁厚的影响较小;各工艺参数对最小壁厚的影响程度为进给率>层间距>成形工具头直径>摩擦因数;最佳工艺参数为成形头直径9 mm、进给率200 mm/min、加工层间距0.2 mm和摩擦因数0.1。结论 通过有限元仿真得出了单点渐进有模成形工艺对制件最小壁厚的影响规律,通过正交试验分析得出了正五边锥形件单点渐进有模成形最佳工艺参数组合,利用该参数组合可以得到壁厚较为均匀的正五边锥形件。 展开更多
关键词 单点渐进 有模成形 数值模拟 工艺参数 正交试验 正五边锥形件
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水平柱群通道全氟己酮过冷沸腾传热特性研究
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作者 胡斌 齐迪 +1 位作者 徐永生 林梅 《西安交通大学学报》 EI CAS CSCD 北大核心 2023年第10期111-120,共10页
为提升散热量不断增加的电力电子器件冷却系统的高效换热能力,提出采用全氟己酮为工质的水平双直角五边形肋柱通道流动沸腾换热系统对其进行冷却。通过实验的方法制作了入口当量直径为3.81 mm的五边形柱群通道结构,对通道内流动沸腾的... 为提升散热量不断增加的电力电子器件冷却系统的高效换热能力,提出采用全氟己酮为工质的水平双直角五边形肋柱通道流动沸腾换热系统对其进行冷却。通过实验的方法制作了入口当量直径为3.81 mm的五边形柱群通道结构,对通道内流动沸腾的平均及沿程换热特性展开了研究,实验工况如下:壁面热流密度为50~400 kW·m^(-2),入口流速为0.1~0.9 m·s^(-1),入口过冷度为15~35℃。结果表明:当热流密度低于100 kW·m-2时,单相对流占主导,增加流速与过冷度能够明显促进壁温降低;当热流密度高于200 kW·m^(-2)时,沸腾吸热占主导,增加流速与过冷度时壁温的降低幅度不明显;在热流密度为400 kW·m^(-2)、过冷度为15℃的工况下,柱群通道的平均传热系数最高;通道沿流向的局部传热系数总体呈现上升趋势,随着热流密度的增大、流速与过冷度的降低,通道出口传热系数相比进口的增长更加显著,此时通道内流体沿流向的沸腾剧烈程度发展速度更快、通道出口的沸腾程度更剧烈。该研究可为水平柱群通道内流动沸腾传热的最佳工况设计提供理论基础。 展开更多
关键词 电子器件冷却 过冷沸腾 水平柱群通道 双直角五边形肋柱 传热特性
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