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可压缩边界层的入口合成湍流生成方法

力学学报 2024年第1期56卷 45-57页

作者：王天孙东郭启龙李辰袁先旭李博中国空气动力研究与发展中心空天飞行空气动力科学与技术全国重点实验室四川绵阳621000

在壁湍流中开展RANS-LES方法混合模拟时,入口处添加合理的湍流脉动能够缩短流场向完全湍流的发展距离,提高数值模拟精度以及节省计算资源.采用SA-IDDES方法对槽道湍流和可压缩湍流边界层开展了数值模拟研究,对比了3种较为常用的合成湍... 详细信息

在壁湍流中开展RANS-LES方法混合模拟时,入口处添加合理的湍流脉动能够缩短流场向完全湍流的发展距离,提高数值模拟精度以及节省计算资源.采用SA-IDDES方法对槽道湍流和可压缩湍流边界层开展了数值模拟研究,对比了3种较为常用的合成湍流方法对流场发展的影响,包括合成湍流生成器(STG)、数字滤波法(DFM)和合成涡方法(SEM);研究了不同合成湍流入口条件下流场壁面摩阻、流场结构、雷诺应力的发展过程,评估了各方法在壁湍流中的表现.其中在不可压槽道湍流和可压缩湍流边界层的模拟中,STG方法展现了较短的摩阻恢复距离,流场结构与雷诺应力发展相比DFM也有一定的优势.在高马赫数湍流边界层的数值模拟中,忽略热力学量脉动可能会降低合成边界层脉动恢复到物理真实脉动的速度.因此,文章进一步基于STG给出的速度脉动,在入口处通过若干强雷诺比拟方法(SRA,GSRA和HSRA)添加热力学脉动量,对比研究了对可压缩湍流边界层流场发展的影响,结果显示是否添加热力学脉动对于流场摩阻和雷诺应力发展影响较小,但对流场中的热力学量影响显著,其中GSRA下流场热力学量恢复得最快.

关键词：合成湍流入口边界条件可压缩性湍流边界层

The -Stabilization of a Heegaard Splitting with Distance at Least 6 is Unstabilized

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Chinese Annals of Mathematics,Series B 2014年第4期35卷 557-562页

作者： Yanqing ZOU qilong guo Ruifeng QIU School of Mathematical Sciences Dalian University of Technology School of Mathematical Sciences Peking University Department of Mathematics East China Normal University

Let M be a compact orientable 3-manifold with 0M connected. If V Us W is a Heegaard splitting of M with distance at least 6, then the 0-stabilization of V Us W along OM is unstabilized. Hence M has at least two unstabilized Heegaard splittings with different genera. The basic tool is a result on disk complex given by Masur and Schleimer.

关键词： Heegaard splitting Distance Stabilization

A Note on Heegaard Genus of Self-amalgamated 3-Manifold

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Chinese Annals of Mathematics,Series B 2015年第1期36卷 51-56页

作者： qilong guo Ruifeng QIU Yanqing ZOU School of Mathematical Sciences Dalian University of Technology Department of Mathematics East China Normal University

Let M be a connected orientable compact irreducible 3-manifold. Suppose that αM consists of two homeomorphic surfaces F1 and F2, and both F1 and F2 are compressible in M. Suppose furthermore that g(M, F1) = g(M) + g(F1), where g(M, F1)is the Heegaard genus of M relative to F1. Let Mfbe the closed orientable 3-manifold obtained by identifying F1 and F2 using a homeomorphism f : F1 → F2. The authors show that if f is sufficiently complicated, then g(Mf) = g(M, αM) + 1.

关键词： Heegaard splitting Self-amalgamated Sufficiently complicated

Analyses of the Dispersion Overshoot and Inverse Dissipation of the High-Order Finite Difference Scheme

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Advances in Applied Mathematics and Mechanics 2013年第6期5卷 809-824页

作者： Qin Li qilong guo Hanxin Zhang State Key Laboratory of Aerodynamics Mianyang 621000SichuanChina National Laboratory of Computational Fluid Dynamics Beijing University of Aeronautics and AstronauticsBeijing 100191China

Analyses were performed on the dispersion overshoot and inverse dissipation of the high-order finite difference scheme using Fourier and precision *** under discussion included the pointwise-and staggered-grid type,and were presented in weighted form using candidate schemes with third-order accuracy and three-point *** of these were commonly used in the construction of difference *** for the dispersion overshoot were presented and their critical states were *** kinds of instabilities were studied due to inverse dissipation,especially those that occur at lower wave *** for the occurrence were presented and the relationship of the two instabilities was *** were made between the analytical results and the dispersion/dissipation relations by Fourier transformation of typical *** an example,an application of the criteria was given for the remedy of inverse dissipation in Weirs&Mart´ın’s third-order scheme.

关键词： High-order difference scheme dispersion overshoot inverse dissipation

Hypersonic Shock Wave/Boundary Layer Interactions by a Third-Order Optimized Symmetric WENO Scheme

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Transactions of Nanjing University of Aeronautics and Astronautics 2017年第5期34卷 524-534页

作者： Li Chen guo qilong Li Qin Zhang Hanxin State Key Laboratory of Aerodynamics China Aerodynamics Research and Development Center Mianyang 621000 P. R. China Computational Aerodynamics Institute China Aerodynamics Research and Development Center Mianyang 621000 P. R. China

A novel third-order optimized symmetric weighted essentially non-oscillatory(WENO-OS3)scheme is used to simulate the hypersonic shock wave/boundary layer ***,the scheme is presented with the achievement of low dissipation in smooth region and robust shock-capturing capabilities in *** Maxwell slip boundary conditions are employed to consider the rarefied effect near the ***,several validating tests are given to show the good resolution of the WENO-OS3 scheme and the feasibility of the Maxwell slip boundary ***,hypersonic flows around the hollow cylinder truncated flare(HCTF)and the25°/55°sharp double cone are *** are made on the characteristics of the hypersonic shock wave/boundary layer interactions with and without the consideration of the slip *** results indicate that the scheme has a good capability in predicting heat transfer with a high resolution for describing fluid *** the slip boundary conditions,the separation region at the corner is smaller and the prediction is more accurate than that with no-slip boundary conditions.

关键词： hypersonic flows shock wave/boundary layer interactions weighted essentially non-oscillatory(WENO)scheme slip boundary conditions

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再生微粉多元复合胶凝体系的性能研究

硅酸盐通报 2024年第5期43卷 1812-1821页

作者：裴军军苑博文高敏郭启龙林政红黑亚萌西北民族大学土木工程学院兰州730124 甘肃省绿色工程材料与低碳建造重点实验室兰州730124

再生微粉复合胶凝体系对再生微粉的应用具有积极作用。本文采用再生微粉-水泥-粉煤灰构建二元/三元复合胶凝体系,研究了再生微粉的掺量对胶砂试块物理、力学性能的影响,并通过XRD和SEM探究了胶砂试块的水化产物和显微结构。结果表明:随... 详细信息

再生微粉复合胶凝体系对再生微粉的应用具有积极作用。本文采用再生微粉-水泥-粉煤灰构建二元/三元复合胶凝体系,研究了再生微粉的掺量对胶砂试块物理、力学性能的影响,并通过XRD和SEM探究了胶砂试块的水化产物和显微结构。结果表明:随着再生微粉掺量的增加,胶砂试块3、7、28 d的抗压强度逐渐下降,需水量增加,流动度下降,干缩值先减小后增大;掺有再生微粉和粉煤灰的复合胶凝体系胶砂试块的干燥收缩在7~14 d发展较快。随着再生微粉和粉煤灰掺量的增加,水化硅酸钙生成量逐渐减少,胶砂试块内部孔隙、裂隙明显增多。再生微粉和粉煤灰对水泥的总取代率最大为40%(质量分数)。

关键词：再生微粉碱激发复合胶凝体系力学性能水化产物干燥收缩

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CMS实验中大动量玻色子喷注探针方法的发展及应用

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科学通报 2024年第22期69卷 3208-3221页

作者：高乐耘付大为赵宇哲郭启隆钱思天杨天一邓森李强北京大学核物理与核技术国家重点实验室北京100871

过去10余年来,大动量玻色子喷注的标记方法受到高能物理理论及实验界的极大关注,已经成为高能量物理前沿领域的推动技术和创新亮点.大动量玻色子常常作为共振产生的重粒子的衰变产物,广泛出现于超出标准模型的新粒子和新物理的寻找工作... 详细信息

过去10余年来,大动量玻色子喷注的标记方法受到高能物理理论及实验界的极大关注,已经成为高能量物理前沿领域的推动技术和创新亮点.大动量玻色子常常作为共振产生的重粒子的衰变产物,广泛出现于超出标准模型的新粒子和新物理的寻找工作中.对大动量的规范玻色子(统称为V)和希格斯玻色子(H),CMS实验组成功开发了V→qq和H→bb等过程的标记技术及校准方案,并成功将其应用于多玻色子共振态的寻找等工作中.本文回顾了10余年来CMS实验中大动量玻色子探针方法的发展及应用,其中包括最新提出的新技术和新方法,特别是人工智能时代到来后出现的与深度学习紧密结合的喷注标记技术.

关键词： CMS实验大动量玻色子探针超出标准模型的新物理深度学习

The Unstabilized Amalgamation of Heegaard Splittings along Disconnected Surfaces

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Journal of Mathematical Research with Applications 2013年第4期33卷 475-482页

作者： Xutao GAO qilong guo School of Mathematical Sciences Dalian University of Technology

Let M be a 3-manifold, F= {F1 , F2 , . . . , Fn } be a collection of essential closed surfaces in M (for any i, j ∈ {1, ..., n}, ifi≠j, Fi is not parallel to Fj and Fi ∩Fj = φ) and0 M be a collection of components of M. Suppose M-UFi ∈FFi×(-1, 1) contains k components M1 , M2 , . . . , Mk . If each M i has a Heegaard splitting ViUSiWi with d(Si) > 4(g(M1 ) + ··· + g(Mk )), then any minimal Heegaard splitting of M relative to 0M is obtained by doing amalgamations and self-amalgamations from minimal Heegaard splittings or -stabilization of minimal Heegaard splittings of M1 , M2 , . . . , Mk .

关键词： unstabilized distance amalgamation Heeaggard splitting.

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基质沥青重复加热后老化规律的试验研究

城市道桥与防洪 2024年第10期 249-251,266,M0023页

作者：裴军军郭启龙庞建利姜艳军西北民族大学土木工程学院甘肃兰州730124 甘肃省新型建材与建筑节能重点实验室甘肃兰州730124

沥青重复加热致使老化会影响沥青路面热再生混合料性能及施工养护质量或科研实验结果的可靠性及稳定性,因此对基质沥青重复加热老化后的指标变化规律进行分析从而在沥青路面热再生及施工养护前或科研实验前掌握沥青的老化程度很有必要... 详细信息

沥青重复加热致使老化会影响沥青路面热再生混合料性能及施工养护质量或科研实验结果的可靠性及稳定性,因此对基质沥青重复加热老化后的指标变化规律进行分析从而在沥青路面热再生及施工养护前或科研实验前掌握沥青的老化程度很有必要且很有意义。通过对重复加热后的基质沥青进行针入度(25℃)、延度(15℃)、软化点、旋转黏度、四组分的试验,探讨沥青重复热氧化后的老化机理及规律。试验结果表明:沥青的针入度和残留针入度比随着老化深入逐渐减小,沥青逐渐变硬变稠,流动度降低;延度的衰减速度相对较快,沥青的变形能力逐渐减弱且衰减速率加快,延展性能变差,针入度和延度分别降为原样的49.4%和46.4%;软化点逐渐增大,产生相同变形所需要的温度逐渐增大,增强沥青的高温稳定性,但同时对低温抗裂性逐渐不利。沥青的旋转黏度随着重复热氧化作用较为显著的增大,较原样增长了44.3%,老化指数也随之增大。饱和分和芳香分含量逐渐减少,饱和分含量由原样的30.36%减少到27.64%,芳香分含量由原样的35.82%减少到33.43%,胶质和沥青质含量逐渐增加,热氧化过程中芳香分和饱和分不断聚合转化成胶质,并进一步转化为沥青质,最后沥青质含量由原来的7.59%增大到12.11%。以上指标的变化使沥青逐渐变硬变脆,黏弹性减弱,变形能力变差,对沥青路用性能产生不利的影响。

关键词：基质沥青针入度延度软化点旋转黏度四组分