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Vortex-Induced Vibration Characteristics of an Underwater Manipulator in Pulsating Flow
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作者 Yongqi Li Xia Liu +3 位作者 Zongqiang Li Derong Duan Senliang Dai Hui Zhang 《哈尔滨工程大学学报(英文版)》 2026年第1期63-81,共19页
Vortex-induced vibration(VIV)of an underwater manipulator in pulsating flow presents a notable engineering problem in precise control due to the velocity variation in the flow.This study investigates the VIV response ... Vortex-induced vibration(VIV)of an underwater manipulator in pulsating flow presents a notable engineering problem in precise control due to the velocity variation in the flow.This study investigates the VIV response of an underwater manipulator subjected to pulsating flow,focusing on how different postures affect the behavior of the system.The effects of pulsating parameters and manipulator arrangement on the hydrodynamic coefficient,vibration response,motion trajectory,and vortex shedding behaviors were analyzed.Results indicated that the cross flow vibration displacement in pulsating flow increased by 32.14%compared to uniform flow,inducing a shift in the motion trajectory from a crescent shape to a sideward vase shape.In the absence of interference between the upper and lower arms,the lift coefficient of the manipulator substantially increased with rising pulsating frequency,reaching a maximum increment of 67.0%.This increase in the lift coefficient led to a 67.05%rise in the vibration frequency of the manipulator in the in-line direction.As the pulsating amplitude increased,the drag coefficient of the underwater manipulator rose by 36.79%,but the vibration frequency in the cross-flow direction decreased by 56.26%.Additionally,when the upper and lower arms remained in a state of mutual interference,the cross-flow vibration amplitudes of the upper and lower arms were approximately 1.84 and 4.82 times higher in a circular-elliptical arrangement compared to an elliptical-circular arrangement,respectively.Consequently,the flow field shifted from a P+S pattern to a disordered pattern,disrupting the regularity of the motion trajectory. 展开更多
关键词 Underwater manipulator Pulsating flow Vortex-induced vibration TRAJECTORY Overlapping mesh method
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Enhanced semi-supervised learning for top gas flow state classification to optimize emission and production in blast ironmaking furnaces
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作者 Song Liu Qiqi Li +3 位作者 Qing Ye Zhiwei Zhao Dianyu E Shibo Kuang 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期204-216,共13页
Automated classification of gas flow states in blast furnaces using top-camera imagery typically demands a large volume of labeled data,whose manual annotation is both labor-intensive and cost-prohibitive.To mitigate ... Automated classification of gas flow states in blast furnaces using top-camera imagery typically demands a large volume of labeled data,whose manual annotation is both labor-intensive and cost-prohibitive.To mitigate this challenge,we present an enhanced semi-supervised learning approach based on the Mean Teacher framework,incorporating a novel feature loss module to maximize classification performance with limited labeled samples.The model studies show that the proposed model surpasses both the baseline Mean Teacher model and fully supervised method in accuracy.Specifically,for datasets with 20%,30%,and 40%label ratios,using a single training iteration,the model yields accuracies of 78.61%,82.21%,and 85.2%,respectively,while multiple-cycle training iterations achieves 82.09%,81.97%,and 81.59%,respectively.Furthermore,scenario-specific training schemes are introduced to support diverse deployment need.These findings highlight the potential of the proposed technique in minimizing labeling requirements and advancing intelligent blast furnace diagnostics. 展开更多
关键词 blast furnace gas flow state semi-supervised learning mean teacher feature loss
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基于GO-FLOW-Markov法的核电站给水系统可靠性分析
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作者 许玉振 赵慧敏 段富海 《大连理工大学学报》 北大核心 2026年第1期57-65,共9页
采用GO-FLOW法分析核电站给水系统的可靠性时,存在无法处理系统中并联备用子系统的问题.为此,提出了一种基于GO-FLOW-Markov的可靠性分析方法,通过建立主系统和备用系统的Markov状态转移矩阵来求解系统可靠度,并以该方法为运算规则,提... 采用GO-FLOW法分析核电站给水系统的可靠性时,存在无法处理系统中并联备用子系统的问题.为此,提出了一种基于GO-FLOW-Markov的可靠性分析方法,通过建立主系统和备用系统的Markov状态转移矩阵来求解系统可靠度,并以该方法为运算规则,提出了一种具有普适性的新操作符备用门,扩展了GO-FLOW法操作符.考虑到系统中存在多组冗余系统,引入 α 因子建立了具有共因失效的给水系统可靠性分析模型并进行计算.结果表明,GO-FLOW-Markov法可用来计算并联备用系统可靠度,且考虑因素比常规GO-FLOW法更全面;核电站给水系统中的共因失效对系统可靠性有明显的影响,因此对复杂系统应该考虑共因失效问题,其可靠度计算结果更贴合工程实际. 展开更多
关键词 核电站给水系统 可靠性分析 GO-flow MARKOV 并联备用
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基于FLOW3D的V型河道滑坡涌浪首浪高度影响因素分析
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作者 王环玲 冯业林 +2 位作者 粟焕 赵富刚 马行生 《三峡大学学报(自然科学版)》 北大核心 2025年第3期1-6,19,共7页
滑坡涌浪是影响山区水库安全运行的主要威胁之一,研究V型河道滑坡涌浪的首浪特征和影响因素对库区灾害防治有重要意义.本文使用FLOW3D计算流体力学方法对V型河道滑坡涌浪灾害进行了系统研究.建立了V型河道滑坡涌浪计算模型,考虑滑坡体... 滑坡涌浪是影响山区水库安全运行的主要威胁之一,研究V型河道滑坡涌浪的首浪特征和影响因素对库区灾害防治有重要意义.本文使用FLOW3D计算流体力学方法对V型河道滑坡涌浪灾害进行了系统研究.建立了V型河道滑坡涌浪计算模型,考虑滑坡体体积、滑速、河道水深、岸坡倾角、滑床摩擦系数等因素,进行了35组不同工况下的滑坡涌浪数值模拟,获取滑坡入水产生涌浪的过程和首浪高度.将数值模拟结果与经验公式进行了对比,分析不同因素对首浪高度的影响程度.结果表明,河道水深、滑床摩擦系数与首浪高度呈负相关,滑坡体积、入水速度、岸坡倾角与首浪高度呈正相关.各因素对首浪高度的影响程度关系为:入水速度>滑坡体积>岸坡倾角>河道水深>滑床摩擦系数.本文研究为山区水库滑坡涌浪灾害防治提供参考. 展开更多
关键词 滑坡涌浪 首浪高度 敏感性分析 V型河道 flow3D
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博物馆中的幸福感:基于flow理论的博物馆游客体验研究
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作者 李璐 《沈阳文旅》 2025年第5期103-105,共3页
目前,博物馆的“活化”发展已成为我国博物馆发展的重要任务,活化发展的核心目标是丰富全社会历史文化滋养,其重要内涵之一就是“以人为本”。本文基于flow体验理论,关注博物馆游客体验,探讨flow理论对提升博物馆游客体验的价值和可行性... 目前,博物馆的“活化”发展已成为我国博物馆发展的重要任务,活化发展的核心目标是丰富全社会历史文化滋养,其重要内涵之一就是“以人为本”。本文基于flow体验理论,关注博物馆游客体验,探讨flow理论对提升博物馆游客体验的价值和可行性,并以理论指导博物馆的具体实践,针对成都博物馆、三星堆博物馆、成都武侯祠博物馆等典型案例进行分析,帮助游客在博物馆活动中获得更多的flow体验和幸福感,让博物馆“以人为本”的教育和服务功能真正发挥作用。 展开更多
关键词 活化发展 幸福感 博物馆游客体验 flow理论
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4D Flow MRI技术对心肌梗死局部血流动能的定量分析 被引量:1
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作者 牛惜情 顿雨桐 +6 位作者 李国策 张厚宁 张斌 潘志斌 边浩 康立清 刘凤海 《中国CT和MRI杂志》 2025年第4期97-100,共4页
目的基于4D Flow MRI技术探究急性心肌梗死患者左心室(left ventricular,LV)腔内局部血流动能(kinetic energy,KE)改变。方法纳入30名急性心肌梗死(acute myocardial infarction,AMI)患者和20名对照者。应用4D Flow MRI技术定量评价左... 目的基于4D Flow MRI技术探究急性心肌梗死患者左心室(left ventricular,LV)腔内局部血流动能(kinetic energy,KE)改变。方法纳入30名急性心肌梗死(acute myocardial infarction,AMI)患者和20名对照者。应用4D Flow MRI技术定量评价左心室腔内血流动能,包括左心室平均动能、最小动能、收缩期动能、舒张期动能以及平面内动能(in-plane kinetic energy,In-plane KE)百分比。比较心肌梗死组和对照组之间以及梗死节段与非梗死节段之间血流动能参数的差异。结果与对照组相比,急性心肌梗死组左心室整体平均动能(10.7μJ/mL±3.3 vs 14.7μJ/mL±3.6,P<0.001)、收缩期动能(14.6μJ/mL±5.1 vs 18.9μJ/mL±3.9,P=0.003)及舒张期动能(7.9μJ/mL±2.5 vs 10.6μJ/mL±3.8,P=0.018)均显著降低,其中梗死节段较非梗死节段邻近心腔血流的平均动能降低而收缩期平面内动能百分比增加(49.5μJ/mL±18.7 vs 126.3μJ/mL±50.7,P<0.001;61.8%±11.5 vs 42.9%±14.4,P=0.001)。结论4D Flow MRI技术可定量评价左心室腔内局部血流动能参数。急性心肌梗死后整体心腔血流动能减低,而梗死节段邻近心腔局部血流平面内动能百分比增加。 展开更多
关键词 4D flow MRI 心肌梗死 血流动力学 血流动能 平面内动能
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基于模糊GO-FLOW法的并网型微电网可靠性评估
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作者 岳大为 姜毅 +3 位作者 杨明哲 李练兵 商悦阳 张帅龙 《太阳能学报》 北大核心 2025年第1期429-437,共9页
由于传统GO-FLOW法存在定常故障率和维修率的局限性,将一种新的可靠性评估算法—模糊GO-FLOW法引入并网型微电网可靠性评估中。首先,基于梯形模糊数,对GO-FLOW法进行改进;随后,根据并网型微电网系统结构,设计新型操作符并建立微电网系... 由于传统GO-FLOW法存在定常故障率和维修率的局限性,将一种新的可靠性评估算法—模糊GO-FLOW法引入并网型微电网可靠性评估中。首先,基于梯形模糊数,对GO-FLOW法进行改进;随后,根据并网型微电网系统结构,设计新型操作符并建立微电网系统的模糊GO-FLOW图,同时对操作符的模糊成功概率进行计算;最后,基于改进的IEEE RBTS BUS6 F4馈线系统,对比分析模糊GO-FLOW法、模糊化前GO-FLOW法和序贯蒙特卡洛模拟法。结果表明,在并网型微电网可靠性评估中,模糊GO-FLOW法具有较高的运算效率和计算精度。 展开更多
关键词 可靠性分析 微电网 光伏发电 GO-flow 梯形模糊数
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基于Moldflow的五通管接头模流分析及模具设计
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作者 黄可 邹华杰 +2 位作者 靳敏 许晨晨 强宇汉 《现代塑料加工应用》 北大核心 2025年第3期33-36,共4页
对某型号五通管接头进行结构分析,获得模具设计难点。将制品模型作缩小处理,在Moldflow 2024模流分析软件中,所有效应下全局变形最严重区域,出现在G1管端处,翘曲率为0.92%;全局变形量最低出现在浇口附近,翘曲率为0.02%。设计主瓣合镶件... 对某型号五通管接头进行结构分析,获得模具设计难点。将制品模型作缩小处理,在Moldflow 2024模流分析软件中,所有效应下全局变形最严重区域,出现在G1管端处,翘曲率为0.92%;全局变形量最低出现在浇口附近,翘曲率为0.02%。设计主瓣合镶件及从动瓣合镶件,保障了内缩动作平顺。通过瓣合成型件在预压弹簧驱动下将模具轴向运动转置为径向运动,实现瓣合成型件与制品的分离。设置隔水管,将制品内侧热量快速导出,以保证制品内外收缩均衡,实现快速注塑。 展开更多
关键词 五通管接头 单浇口 翘曲率 抽芯机构 模流分析
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基于Moldflow的无人机探照灯灯筒模流分析
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作者 张晓光 孟枭 程志超 《合成树脂及塑料》 北大核心 2025年第6期59-63,共5页
以采用聚酰胺为原料制备的无人机探照灯灯筒为研究对象,利用Moldflow软件从探照灯灯筒的填充时间、流动前沿温度、熔接痕、气穴、翘曲变形5个方面对2种浇口位置方案进行对比分析,得到最优的浇口方案,并对2种冷却系统的冷却液温差、回路... 以采用聚酰胺为原料制备的无人机探照灯灯筒为研究对象,利用Moldflow软件从探照灯灯筒的填充时间、流动前沿温度、熔接痕、气穴、翘曲变形5个方面对2种浇口位置方案进行对比分析,得到最优的浇口方案,并对2种冷却系统的冷却液温差、回路管壁温差、冷冻层百分比参数进行对比,得到较优的冷却系统方案。通过对锁模力及注射压力的模拟分析对比,选择符合成型要求的注塑机。利用正交试验降低了探照灯灯筒的体积收缩率,并通过塑件的总体温度分布、剪切速率与体积分布进行验证。结果表明:最佳参数为熔体温度275℃,模具温度80℃,冷却时间30 s。 展开更多
关键词 聚酰胺 模流分析 正交试验 模具设计 探照灯灯筒
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三星水晶成像联合MV FLow微血管成像技术对胎盘植入的诊断研究
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作者 程志坚 金环 +4 位作者 凌佳 龙建妹 华山 蒋婷 冯莉莉 《宜春学院学报》 2025年第3期53-55,72,共4页
目的:探讨三星水晶成像联合MV FLow微血管成像技术在胎盘植入早期诊断的价值。方法:选取2020年12月~2023年12月在江西省人民医院于孕28—40周进行规范化超声检查并定期接受产检,怀疑胎盘植入的73例孕妇为研究对象,均使用三星水晶成像联... 目的:探讨三星水晶成像联合MV FLow微血管成像技术在胎盘植入早期诊断的价值。方法:选取2020年12月~2023年12月在江西省人民医院于孕28—40周进行规范化超声检查并定期接受产检,怀疑胎盘植入的73例孕妇为研究对象,均使用三星水晶成像联合MV FLow微血管成像技术观察胎盘与子宫壁肌壁和膀胱以及直肠的联系,同时均行MRI检查,与术后病理结果进行比较,评价三星水晶成像联合MV FLow微血管成像技术观察胎盘植入的诊断价值及临床应用意义。结果:通过三星水晶成像联合MV FLow微血管成像技术确诊为胎盘植入的孕妇诊断符合率与手术病理一致性较好,Kappa值=0.776。三星水晶成像联合MV FLow微血管成像技术确诊为胎盘植入的孕妇诊断灵敏度与特异度较MRI无明显差异,(P>0.05)。结论:三星水晶成像联合MV FLow微血管成像技术可作为产前胎盘植入的有效诊断方法。 展开更多
关键词 三星水晶成像 MV flow微血管成像 胎盘植入
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基于Solidworks Flow Simulation的换热器翅片形状对换热量影响研究
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作者 张蓬菲 李俊 +2 位作者 孙丽婷 张慧跃 张宇 《山东化工》 2025年第7期205-209,共5页
利用Solidworks Flow Simulation软件,对不同翅片形状的翅片管式换热器进行数值模拟研究,探讨了在相同翅片面积、不考虑翅片厚度的前提下,翅片形状分别为正三角形、正方形、正六边形、正八边形、圆形时换热量的差异。通过建立不同翅片... 利用Solidworks Flow Simulation软件,对不同翅片形状的翅片管式换热器进行数值模拟研究,探讨了在相同翅片面积、不考虑翅片厚度的前提下,翅片形状分别为正三角形、正方形、正六边形、正八边形、圆形时换热量的差异。通过建立不同翅片形状的翅片管式换热器三维模型,设定合理的边界条件和物理属性,在保证其他所有物理参数、材料属性保持不变的前提下,分析了不同翅片形状的翅片管式换热器的热传递过程,计算出热交换系数、热通量、壁面温度、流体平均温度等数值,从而总结换热量的差异,归纳出翅片形状带给换热量的影响。研究表明,翅片形状对换热器的换热量有显著影响,若翅片形状为边数更多的正多边形,即翅片更接近于圆形,则换热量更小。换热量趋于稳态后,通过提取相同迭代次数区间的换热量数值,计算区间内换热量数值方差,发现三角形至六边形换热稳定性渐变稳定,从六边形至圆形稳定性逐渐降低。此研究为翅片管式换热器设计优化提供了理论依据。 展开更多
关键词 翅片管式换热器 翅片形状 Solidworks flow Simulation 换热量 CFD 数值模拟
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Integrated Equipment with Functions of Current Flow Control and Fault Isolation for Multiterminal DC Grids 被引量:1
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作者 Shuo Zhang Guibin Zou 《Energy Engineering》 EI 2025年第1期85-99,共15页
The multi-terminal direct current(DC)grid has extinctive superiorities over the traditional alternating current system in integrating large-scale renewable energy.Both the DC circuit breaker(DCCB)and the current flow ... The multi-terminal direct current(DC)grid has extinctive superiorities over the traditional alternating current system in integrating large-scale renewable energy.Both the DC circuit breaker(DCCB)and the current flow controller(CFC)are demanded to ensure the multiterminal DC grid to operates reliably and flexibly.However,since the CFC and the DCCB are all based on fully controlled semiconductor switches(e.g.,insulated gate bipolar transistor,integrated gate commutated thyristor,etc.),their separation configuration in the multiterminal DC grid will lead to unaffordable implementation costs and conduction power losses.To solve these problems,integrated equipment with both current flow control and fault isolation abilities is proposed,which shares the expensive and duplicated components of CFCs and DCCBs among adjacent lines.In addition,the complicated coordination control of CFCs and DCCBs can be avoided by adopting the integrated equipment in themultiterminal DC grid.In order to examine the current flow control and fault isolation abilities of the integrated equipment,the simulation model of a specific meshed four-terminal DC grid is constructed in the PSCAD/EMTDC software.Finally,the comparison between the integrated equipment and the separate solution is presented a specific result or conclusion needs to be added to the abstract. 展开更多
关键词 Integrated equipment multiterminal direct current grid current flow control fault isolation
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Particle transport in fractured geo-energy reservoirs considering the effect of fluid inertia and turbulent flow:A review 被引量:2
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作者 E.A.A.V.Edirisinghe M.S.A.Perera +2 位作者 D.Elsworth S.K.Matthai E.Goudeli 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1906-1939,共34页
Particle-fluid two-phase flows in rock fractures and fracture networks play a pivotal role in determining the efficiency and effectiveness of hydraulic fracturing operations,a vital component in unconventional oil and... Particle-fluid two-phase flows in rock fractures and fracture networks play a pivotal role in determining the efficiency and effectiveness of hydraulic fracturing operations,a vital component in unconventional oil and gas extraction.Central to this phenomenon is the transport of proppants,tiny solid particles injected into the fractures to prevent them from closing once the injection is stopped.However,effective transport and deposition of proppant is critical in keeping fracture pathways open,especially in lowpermeability reservoirs.This review explores,then quantifies,the important role of fluid inertia and turbulent flows in governing proppant transport.While traditional models predominantly assume and then characterise flow as laminar,this may not accurately capture the complexities inherent in realworld hydraulic fracturing and proppant emplacement.Recent investigations highlight the paramount importance of fluid inertia,especially at the high Reynolds numbers typically associated with fracturing operations.Fluid inertia,often overlooked,introduces crucial forces that influence particle settling velocities,particle-particle interactions,and the eventual deposition of proppants within fractures.With their inherent eddies and transient and chaotic nature,turbulent flows introduce additional complexities to proppant transport,crucially altering proppant settling velocities and dispersion patterns.The following comprehensive survey of experimental,numerical,and analytical studies elucidates controls on the intricate dynamics of proppant transport under fluid inertia and turbulence-towards providing a holistic understanding of the current state-of-the-art,guiding future research directions,and optimising hydraulic fracturing practices. 展开更多
关键词 Two-phase flows Rock fractures Proppant transport Fluid inertia Turbulent flows Hydraulic fracturing
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Experimental and modeling investigation of zero net liquid flow in hilly terrain pipeline 被引量:1
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作者 Bo Huang Qiang Xu +4 位作者 Ying-Jie Chang Ye-Qi Cao Hai-Yang Yu Yu-Wen Li Lie-Jin Guo 《Petroleum Science》 2025年第5期2183-2202,共20页
Hilly terrain pipeline is a common form of pipeline in oil and gas storage and transportation industry.Due to the hilly terrain influence, the liquid at the elbow of the gathering pipeline is easy to flow back and acc... Hilly terrain pipeline is a common form of pipeline in oil and gas storage and transportation industry.Due to the hilly terrain influence, the liquid at the elbow of the gathering pipeline is easy to flow back and accumulate to form slug flow, so it is necessary to remove the accumulated liquid by gas purging. In this paper, experiment is carried out in hilly terrain pipelines. Three flow patterns of stratified flow, slug flow and stratified entrained flow are observed. The process of gas purging accumulated liquid is divided into four stages, namely liquid accumulation, liquid rising, continuous outflow and tail outflow. At the same time, the flow pattern maps of each stage are drawn. The pressure drop signal is analyzed in time domain and frequency domain, and the contour map of pressure drop distribution is drawn. It is found that the ratio of range to average value can well distinguish the occurrence range of each flow pattern.Based on visualization, the transition process of slug flow to stratified flow and stratified entrained flow is studied, and the transition boundary prediction model is established. An image processing method is proposed to convert the image signal into a similarity curve, and PSD analysis is performed to calculate the slug frequency. The normal distribution is used to fit the slug frequency, and the predicted correlation is in good agreement with the experimental data. 展开更多
关键词 Hilly terrain pipeline Zero net liquid flow Slug flow flow pattern transition Quantitative image processing
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Modelling of Daily Long-Term Urban Road Traffic Flow Distribution: A Poisson Process Approach 被引量:1
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作者 Jojo D. Lartey 《Open Journal of Modelling and Simulation》 2025年第1期89-105,共17页
Road traffic flow forecasting provides critical information for the operational management of road mobility challenges, and models are used to generate the forecast. This paper uses a random process to present a novel... Road traffic flow forecasting provides critical information for the operational management of road mobility challenges, and models are used to generate the forecast. This paper uses a random process to present a novel traffic modelling framework for aggregate traffic on urban roads. The main idea is that road traffic flow is random, even for the recurrent flow, such as rush hour traffic, which is predisposed to congestion. Therefore, the structure of the aggregate traffic flow model for urban roads should correlate well with the essential variables of the observed random dynamics of the traffic flow phenomena. The novelty of this paper is the developed framework, based on the Poisson process, the kinematics of urban road traffic flow, and the intermediate modelling approach, which were combined to formulate the model. Empirical data from an urban road in Ghana was used to explore the model’s fidelity. The results show that the distribution from the model correlates well with that of the empirical traffic, providing a strong validation of the new framework and instilling confidence in its potential for significantly improved forecasts and, hence, a more hopeful outlook for real-world traffic management. 展开更多
关键词 Poisson Process Macroscopic Traffic flow Urban Road Long-Term Forecast Multiple Entries-Exits Dynamics
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Numerical Study of Cavitating Flows around a Hydrofoil with Deep Analysis of Vorticity Effects 被引量:1
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作者 Shande Li Wen’an Zhong +1 位作者 Shaoxing Yu Hao Wang 《Fluid Dynamics & Materials Processing》 2025年第1期179-204,共26页
This paper aims to numerically explore the characteristics of unsteady cavitating flow around a NACA0015 hydrofoil,with a focus on vorticity attributes.The simulation utilizes a homogeneous mixture model coupled with ... This paper aims to numerically explore the characteristics of unsteady cavitating flow around a NACA0015 hydrofoil,with a focus on vorticity attributes.The simulation utilizes a homogeneous mixture model coupled with a filter-based density correction turbulence model and a modified Zwart cavitation model.The study investigates the dynamic cavitation features of the thermal fluid around the hydrofoil at various incoming flow velocities.It systematically elucidates the evolution of cavitation and vortex dynamics corresponding to each velocity condition.The results indicate that with increasing incoming flow velocity,distinct cavitation processes take place in the flow field. 展开更多
关键词 Cavitating flow HYDROFOIL flow velocity VORTICITY Computational Fluid Dynamics(CFD)
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Study of an adaptive bump control mechanism for shock wave/boundary layer interactions in supersonic flows 被引量:1
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作者 Shan-Shan Tian Liang Jin +2 位作者 Wei Huang Yang Shen Kai An 《Theoretical & Applied Mechanics Letters》 2025年第4期319-330,共12页
The stability of supersonic inlets faces challenges due to various changes in flight conditions,and flow control methods that address shock wave/boundary layer interactions under only one set of conditions cannot meet... The stability of supersonic inlets faces challenges due to various changes in flight conditions,and flow control methods that address shock wave/boundary layer interactions under only one set of conditions cannot meet developmental requirements.This paper proposes an adaptive bump control scheme and employs dynamic mesh technology for numerical simulation to investigate the unsteady control effects of adaptive bumps.The obtained results indicate that the use of moving bumps to control shock wave/boundary layer interactions is feasible.The adaptive control effects of five different bump speeds are evaluated.Within the range of bump speeds studied,the analysis of the flow field structure reveals the patterns of change in the separation zone area during the control process,as well as the relationship between the bump motion speed and the control effect on the separation zone.It is concluded that the moving bump endows the boundary layer with additional energy. 展开更多
关键词 Shock wave/boundary layer interaction ADAPTIVE flow control BUMP Supersonic flow
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Boundary fluid constraints during electrochemical jet machining of large size emerging titanium alloy aerospace parts in gas–liquid flows:Experimental and numerical simulation 被引量:1
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作者 Yang LIU Ningsong QU +1 位作者 Hansong LI Zhaoyang ZHANG 《Chinese Journal of Aeronautics》 2025年第1期115-130,共16页
Large size titanium alloy parts are widely used in aerospace.However,they are difficult to manufacture using mechanical cutting technology because of severe tool wear.Electrochemical jet machining is a promising techn... Large size titanium alloy parts are widely used in aerospace.However,they are difficult to manufacture using mechanical cutting technology because of severe tool wear.Electrochemical jet machining is a promising technology to achieve high efficiency,because it has high machining flexibility and no machining tool wear.However,reports on the macro electrochemical jet machining of large size titanium alloy parts are very scarce,because it is difficult to achieve effective constraint of the flow field in macro electrochemical jet machining.In addition,titanium alloy is very sensitive to fluctuation of the flow field,and a turbulent flow field would lead to serious stray corrosion.This paper reports a series of investigations of the electrochemical jet machining of titanium alloy parts.Based on the flow analysis and experiments,the machining flow field was effectively constrained.TB6 titanium alloy part with a perimeter of one meter was machined.The machined surface was smooth with no obvious machining defects.The machining process was particularly stable with no obvious spark discharge.The research provides a reference for the application of electrochemical jet machining technology to achieve large allowance material removal in the machining of large titanium alloy parts. 展开更多
关键词 Electrochemical jet machining Titanium alloys Large size parts flow simulation Turbulent flow
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基于XFlow的仿蝴蝶气动特性 被引量:1
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作者 饶小龙 来永斌 王龙 《科学技术与工程》 北大核心 2025年第9期3680-3686,共7页
为了研究非定常飞行参数对仿蝴蝶气动特性的影响问题,以黑框蓝闪蝶作为研究对象,通过建立飞行动力学模型;依据飞行原理建立蝴蝶飞行时翅膀、躯干、地面的相对坐标,构建飞行过程中蝴蝶翅膀和躯干的运动学方程。结合蝴蝶飞行原理验证仿蝴... 为了研究非定常飞行参数对仿蝴蝶气动特性的影响问题,以黑框蓝闪蝶作为研究对象,通过建立飞行动力学模型;依据飞行原理建立蝴蝶飞行时翅膀、躯干、地面的相对坐标,构建飞行过程中蝴蝶翅膀和躯干的运动学方程。结合蝴蝶飞行原理验证仿蝴蝶气动特性,并在自然环境流场条件下研究仿蝴蝶扑动角和俯仰角改变对升力和阻力的影响,分析其飞行流场。结果表明:翻转角与升力之间存在正相关,与阻力无关;扑动角小于120°时与升力呈正相关,大于120°与升力呈负相关,扑动角与阻力呈负相关;下扑时翅膀前缘开始产生高压区,上扑时翅膀边缘开始产生高压区。研究结果为仿蝴蝶扑翼飞行器设计提供了控制参数和翅膀设计参考,为进一步优化仿生扑翼飞行提供科学依据。 展开更多
关键词 仿生扑翼 飞行参数 Xflow 流场模拟 气动力分析
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Sparse pipeline wall information-based data-driven reconstruction for solid–liquid two-phase flow in flexible vibrating pipelines 被引量:1
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作者 Shengpeng Xiao Chuyi Wan +6 位作者 Hongbo Zhu Dai Zhou Juxi Hu Mengmeng Zhang Yuankun Sun Yan Bao Ke Zhao 《International Journal of Mining Science and Technology》 2025年第11期1885-1903,共19页
Deep-sea mineral resource transportation predominantly utilizes hydraulic pipeline methodology.Environmental factors induce vibrations in flexible pipelines,thereby affecting the internal flow characteristics.Therefor... Deep-sea mineral resource transportation predominantly utilizes hydraulic pipeline methodology.Environmental factors induce vibrations in flexible pipelines,thereby affecting the internal flow characteristics.Therefore,real-time monitoring of solid–liquid two-phase flow in pipelines is crucial for system maintenance.This study develops an autoencoder-based deep learning framework to reconstruct three-dimensional solid–liquid two-phase flow within flexible vibrating pipelines utilizing sparse wall information from sensors.Within this framework,separate X-model and F-model with distinct hidden-layer structures are established to reconstruct the coordinates and flow field information on the computational domain grid of the pipeline under traveling wave vibration.Following hyperparameter optimization,the models achieved high reconstruction accuracy,demonstrating R^(2)values of 0.990 and 0.945,respectively.The models’robustness is evaluated across three aspects:vibration parameters,physical fields,and vibration modes,demonstrating good reconstruction performance.Results concerning sensors show that 20 sensors(0.06%of total grids)achieve a balance between accuracy and cost,with superior accuracy obtained when arranged along the full length of the pipe compared to a dense arrangement at the front end.The models exhibited a signal-to-noise ratio tolerance of approximately 27 dB,with reconstruction accuracy being more affected by sensor failures at both ends of the pipeline. 展开更多
关键词 Particles Solid-liquid two-phase flow Vibration Flexible pipelines Deep learning RECONSTRUCTION
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