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Multi-peak Nodal Solutions for a Two-dimensional Elliptic Problem with Large Exponent in Weighted Nonlinearity
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作者 Yi-bin ZHANG Hai-tao YANG 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2015年第1期261-276,共16页
We consider the boundary value problem△u+︳x︳^2α︳u︳p-1u=0,-1〈α≠0.in the unit ballB with the homogeneous Dirichlet boundary condition, when p is a large exponent. By a constructive way, weprove that for any po... We consider the boundary value problem△u+︳x︳^2α︳u︳p-1u=0,-1〈α≠0.in the unit ballB with the homogeneous Dirichlet boundary condition, when p is a large exponent. By a constructive way, weprove that for any positive integer m, there exists a multi-peak nodal solution vp whose maxima and minima arelocated alternately near the origin and the other m points q1=(λcos^2Л(1-1)/m,λsin 2Л(1-1)/m,1=2,…,m+1such that as p goes to +∞ ,p︳x︳2α︳up︳p-1 up→8Лe(1+α)(1+α)δ0+∑^m+1δ_1=28Лe(-1)l-1δql,whereλ∈(0, 1), m is an odd number with(1+α)(m+2) -- 1 〉 0, or m is an even number. The same techniqueslead also to a more general result on general domains. 展开更多
关键词 multi-peak nodal solutions large exponent finite dimensional reduction
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THE EXISTENCE AND LOCAL UNIQUENESS OF MULTI-PEAK SOLUTIONS TO A CLASS OF KIRCHHOFF TYPE EQUATIONS
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作者 崔磊磊 郭佳星 李工宝 《Acta Mathematica Scientia》 SCIE CSCD 2023年第3期1131-1160,共30页
In this paper,we study the existence and local uniqueness of multi-peak solutions to the Kirchhoff type equations-(ε^(2)a+εb∫_(R^(3))|■u|^(2))△u+V(x)u=u^(p),u>0 in R^(3),which concentrate at non-degenerate cri... In this paper,we study the existence and local uniqueness of multi-peak solutions to the Kirchhoff type equations-(ε^(2)a+εb∫_(R^(3))|■u|^(2))△u+V(x)u=u^(p),u>0 in R^(3),which concentrate at non-degenerate critical points of the potential function V(x),where a,b>0,1<p<5 are constants,andε>0 is a parameter.Applying the Lyapunov-Schmidt reduction method and a local Pohozaev type identity,we establish the existence and local uniqueness results of multi-peak solutions,which concentrate at{a_(i)}1≤i≤k,where{a_(i)}1≤i≤k are non-degenerate critical points of V(x)asε→0. 展开更多
关键词 Kirchhoff type equations potential functions having non-degenerate critical points the Lyapunov-Schmidt reduction method multi-peak solutions existence and local uniqueness
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THE EXISTENCE AND LOCAL UNIQUENESS OF MULTI-PEAK POSITIVE SOLUTIONS TO A CLASS OF KIRCHHOFF EQUATION 被引量:4
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作者 李工宝 牛亚慧 《Acta Mathematica Scientia》 SCIE CSCD 2020年第1期90-112,共23页
In the present paper,we consider the nonlocal Kirchhoff problem-(ε^2a+εb∫|■u|^2)Δu+u=Q(x)u^p,u>0 in R^3,,where a,b>0,1<p<5 andε>0 is a parameter.Under some assumptions on Q(x),we show the existenc... In the present paper,we consider the nonlocal Kirchhoff problem-(ε^2a+εb∫|■u|^2)Δu+u=Q(x)u^p,u>0 in R^3,,where a,b>0,1<p<5 andε>0 is a parameter.Under some assumptions on Q(x),we show the existence and local uniqueness of positive multi-peak solutions by LyapunovSchmidt reduction method and the local Pohozaev identity method,respectly. 展开更多
关键词 KIRCHHOFF equations multi-peak positive solutions LOCAL UNIQUENESS LOCAL Pohozaev identity Lyapunov-Schmidt reduction
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ON THE EXISTENCE AND NODAL CHARACTER OF SOLUTIONS OF SINGULAR NONLINEAR BOUNDARY VALUE PROBLEMS 被引量:1
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作者 曹道珉 邓引斌 《Acta Mathematica Scientia》 SCIE CSCD 1990年第4期471-478,共8页
In this paper we prove the existence of k-node solution of singular nonlinear boundary value problems for each k is-an-element-of N union {0}.
关键词 ON THE EXISTENCE AND nodal CHARACTER OF solutions OF SINGULAR NONLINEAR BOUNDARY VALUE PROBLEMS BVP
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ON THE EXISTENCE AND NODAL CHARACTER OF THE SOLUTIONS OF SINGULAR NONLINEAR BOUNDARY VALUE PROBLEMS 被引量:1
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作者 曹道珉 邓引斌 《Acta Mathematica Scientia》 SCIE CSCD 1991年第4期443-461,共19页
1. Introduction We consider the singular nonlinear boundary value problem where l=v+3/v-1,l+1 is the critical exponent of the embedding of weighted Sobolev space Wt21,2(O, +∞) into Lt2q(O, ∞), v>2. When v=N-1... 1. Introduction We consider the singular nonlinear boundary value problem where l=v+3/v-1,l+1 is the critical exponent of the embedding of weighted Sobolev space Wt21,2(O, +∞) into Lt2q(O, ∞), v>2. When v=N-1 we can get the radial solutions of problem where 2*=2N/N-2 is the critical exponent of the Sobolev embedding H1(Rn)→LQ(RN). Kurtz has discussed the existence of κ-node solution of (1.1), (1.2) for each κ∈N U{0} when the growth rate of |u|l-1u+f(u) is lower then |u|v+3/v-1 i.e. 展开更多
关键词 ON THE EXISTENCE AND nodal CHARACTER OF THE solutions OF SINGULAR NONLINEAR BOUNDARY VALUE PROBLEMS
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GLOBAL STRUCTURE OF A NODAL SOLUTIONS SET OF MEAN CURVATURE EQUATION IN STATIC SPACETIME
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作者 罗华 代国伟 《Acta Mathematica Scientia》 SCIE CSCD 2022年第5期2078-2086,共9页
By bifurcation and topological methods,we study the global structure of a radial nodal solutions set of the mean curvature equation in a standard static spacetime div {a∇u√1−a^(2)|∇u|^(2)+g(∇u,∇a)/√1−a^(2)|∇u|^(2)=... By bifurcation and topological methods,we study the global structure of a radial nodal solutions set of the mean curvature equation in a standard static spacetime div {a∇u√1−a^(2)|∇u|^(2)+g(∇u,∇a)/√1−a^(2)|∇u|^(2)=λNH,with a 0-Dirichlet boundary condition on the unit ball.According to the behavior of H near 0,we obtain the global structure of sign-changing radial spacelike graphs for this problem. 展开更多
关键词 BIFURCATION static spacetime mean curvature operator nodal solution
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ARBITRARILY SMALL NODAL SOLUTIONS FOR PARAMETRIC ROBIN(p,q)-EQUATIONS PLUS AN INDEFINITE POTENTIAL
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作者 Salvatore LEONARDI Nikolaos S.PAPAGEORGIOU 《Acta Mathematica Scientia》 SCIE CSCD 2022年第2期561-574,共14页
We consider a nonlinear Robin problem driven by the(p,q)-Laplacian plus an indefinite potential term and with a parametric reaction term.Under minimal conditions on the reaction function,which concern only its behavio... We consider a nonlinear Robin problem driven by the(p,q)-Laplacian plus an indefinite potential term and with a parametric reaction term.Under minimal conditions on the reaction function,which concern only its behavior near zero,we show that,for all λ>0 small,the problem has a nodal solution y_(λ)∈C^(1)(Ω)and we have y_(λ)→0 in C^(1)(Ω)asλ→0^(+). 展开更多
关键词 (p q)-Laplacian indefinite potential nonlinear regularity extremal constant sign solutions nodal solutions
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LOCALIZED NODAL SOLUTIONS FOR SCHRODINGER-POISSON SYSTEMS
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作者 王星 何锐 刘祥清 《Acta Mathematica Scientia》 SCIE CSCD 2022年第5期1947-1970,共24页
In this paper,we study the existence of localized nodal solutions for Schrodinger-Poisson systems with critical growth{−ε^(2)Δv+V(x)v+λψv=v^(5)+μ|v|^(q−2)v,in R^(3),−ε^(2)Δψ=v^(2),in R^(3);v(x)→0,ψ(x)→0as|x... In this paper,we study the existence of localized nodal solutions for Schrodinger-Poisson systems with critical growth{−ε^(2)Δv+V(x)v+λψv=v^(5)+μ|v|^(q−2)v,in R^(3),−ε^(2)Δψ=v^(2),in R^(3);v(x)→0,ψ(x)→0as|x|→∞.We establish,for smallε,the existence of a sequence of localized nodal solutions concentrating near a given local minimum point of the potential function via the perturbation method,and employ some new analytical skills to overcome the obstacles caused by the nonlocal term φu(x)=1/4π∫R^(3)u^(2)(y)/|x−y|dy.Our results improve and extend related ones in the literature. 展开更多
关键词 Schrodinger-Poisson systems localized nodal solutions perturbation method
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Asymptotic Behavior of Nodal Solutions for Semilinear Elliptic Equationsin R^n
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作者 綦建刚 刘衍胜 《Chinese Quarterly Journal of Mathematics》 CSCD 1998年第1期22-28, ,共7页
In this paper,we have investigated the asymptotic behavior of nodal solutions of semilinear elliptic equations in R n. We conclude more precise and extensive results and give the expression of asymptotic behavior near... In this paper,we have investigated the asymptotic behavior of nodal solutions of semilinear elliptic equations in R n. We conclude more precise and extensive results and give the expression of asymptotic behavior near ∞ more detail than that of [3]-[5]. 展开更多
关键词 半线性椭圆型方程 nodal 渐近性
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EXISTENCE OF NODAL SOLUTION FOR SEMI-LINEAR ELLIPTIC EQUATIONS WITH CRITICAL SOBOLEV EXPONENT ON SINGULAR MANIFOLD 被引量:2
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作者 刘晓春 梅媛 《Acta Mathematica Scientia》 SCIE CSCD 2013年第2期543-555,共13页
In this article, we prove that semi-linear elliptic equations with critical cone Sobolev exponents possess a nodal solution.
关键词 Cone Sobolev space critical exponent nodal solution
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THREE NONTRIVIAL SOLUTIONS FOR A NONLINEAR ANISOTROPIC NONLOCAL EQUATION
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作者 Amin ESFAHANI 《Acta Mathematica Scientia》 SCIE CSCD 2018年第4期1296-1310,共15页
In this article, we establish the existence of a sign-changing solution and two sign- constant solutions for nonlinear nonlocal problem involving the BO-ZK operator on bounded domain. Our main tool is constrained mini... In this article, we establish the existence of a sign-changing solution and two sign- constant solutions for nonlinear nonlocal problem involving the BO-ZK operator on bounded domain. Our main tool is constrained minimization on appropriate Nehari manifolds. 展开更多
关键词 sign-constant and nodal solutions BO-ZK operator variational method
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Non-existence of Multi-peak Solutions to the Schrödinger-Newton System with L2-constraint
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作者 Qing GUO Li-xiu DUAN 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2023年第4期868-877,共10页
In this paper, we are concerned with the the Schrödinger-Newton system with L^(2)-constraint. Precisely, we prove that there cannot exist multi-peak normalized solutions concentrating at k different critical poin... In this paper, we are concerned with the the Schrödinger-Newton system with L^(2)-constraint. Precisely, we prove that there cannot exist multi-peak normalized solutions concentrating at k different critical points of V(x) under certain assumptions on asymptotic behavior of V(x) and its first derivatives near these points. Especially, the critical points of V(x) in this paper must be degenerate.The main tools are a local Pohozaev type of identity and the blow-up analysis. Our results also show that the asymptotic behavior of concentrated points to Schrödinger-Newton problem is quite different from the classical Schrödinger equations, which is mainly caused by the nonlocal term. 展开更多
关键词 Schrödinger-Newton equation NON-EXISTENCE multi-peak solutions Normalized solutions Pohozaev identity
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Explicit solutions for a class of nonlinear BSDEs and their nodal sets
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作者 Zengjing Chen Shuhui Liu +1 位作者 Zhongmin Qian Xingcheng Xu 《Probability, Uncertainty and Quantitative Risk》 2022年第4期283-300,共18页
In this paper,we investigate a class of nonlinear backward stochastic differential equations(BSDEs)arising from financial economics,and give the sign of corresponding solution.Furthermore,we are able to obtain explici... In this paper,we investigate a class of nonlinear backward stochastic differential equations(BSDEs)arising from financial economics,and give the sign of corresponding solution.Furthermore,we are able to obtain explicit solutions to an interesting class of nonlinear BSDEs,including the k-ignorance BSDE arising from the modeling of ambiguity of asset pricing.Moreover,we show its applications in PDEs and contingent pricing in an incomplete market. 展开更多
关键词 Explicit solution Feynman-Kac formula Girsanov’s formula nodal set Nonlinear BSDE Parabolic equation Tanaka’s formula.
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基于六节点三角形单元和线性规划模型的上限有限元研究 被引量:7
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作者 杨峰 阳军生 +1 位作者 李昌友 张箭 《岩石力学与工程学报》 EI CAS CSCD 北大核心 2012年第12期2556-2563,共8页
目前三节点三角形单元常用于极限分析上限有限元,该低阶单元在模拟岩土体失稳破坏时形成的剪切带和塑性区时精度较低。为此,在已有研究成果的基础上,将二阶的六节点三角形单元引入上限有限元,且在单元公共边设置速度间断线并建立线性规... 目前三节点三角形单元常用于极限分析上限有限元,该低阶单元在模拟岩土体失稳破坏时形成的剪切带和塑性区时精度较低。为此,在已有研究成果的基础上,将二阶的六节点三角形单元引入上限有限元,且在单元公共边设置速度间断线并建立线性规划模型,进一步将该单元的应用扩展到服从莫尔-库仑屈服准则的土体。通过对上限有限元进行理论推导并编制程序,利用典型算例研究屈服准则线性化和速度间断线辅助变量线性化对计算结果的影响,并与三节点三角形单元所得结果进行对比分析。研究表明,同等单元数目条件下六节点三角形单元应用于上限有限元能提高计算精度,不过对于某些破坏区域约束不太强烈模型而言,当速度间断线作用显著发挥时,采用三节点三角形单元也可获得良好的解答。 展开更多
关键词 土力学 极限分析 上限有限元 速度间断线 三节点三角形单元 六节点三角形单元 线性规划
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基于加权最小二乘法的供水管网节点流量校核 被引量:6
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作者 范江 杜坤 +2 位作者 周明 徐冰峰 龙天渝 《土木建筑与环境工程》 CSCD 北大核心 2016年第3期73-79,共7页
管网水力模型是实现供水系统现代化管理的重要工具,要使水力模型能比较准确地反映管网真实运行状态,达到预期使用目的,其中的参数需要校核。将管网节点流量校核作为优化问题,采用加权最小二乘法逐步迭代求解,与已有研究相比,采用矩阵分... 管网水力模型是实现供水系统现代化管理的重要工具,要使水力模型能比较准确地反映管网真实运行状态,达到预期使用目的,其中的参数需要校核。将管网节点流量校核作为优化问题,采用加权最小二乘法逐步迭代求解,与已有研究相比,采用矩阵分析法推导供水管网雅克比矩阵解析式,引入水量分配矩阵聚合节点流量,将欠定问题转化为超定,提高了校核的计算效率和结果的可靠性。采用简单管网阐明了雅克比矩阵的计算、节点流量的聚合及梯度向量的构造,利用实际管网验证了方法的实用性。 展开更多
关键词 供水管网 节点流量校核 加权最小二乘法 雅克比矩阵 解析式
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浅埋隧道掌子面稳定性二维自适应上限有限元分析 被引量:17
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作者 阳军生 张箭 杨峰 《岩土力学》 EI CAS CSCD 北大核心 2015年第1期257-264,共8页
为研究浅埋隧道掌子面稳定性及获取精细化的破坏模式,提出了一种上限有限元非结构化网格自适应加密策略。以单元耗散能权重指标作为网格自适应加密评判准则,该策略同时兼顾了单元尺度与塑性应变。应用高阶的6节点三角形单元并建立上限... 为研究浅埋隧道掌子面稳定性及获取精细化的破坏模式,提出了一种上限有限元非结构化网格自适应加密策略。以单元耗散能权重指标作为网格自适应加密评判准则,该策略同时兼顾了单元尺度与塑性应变。应用高阶的6节点三角形单元并建立上限有限元线性规划模型,以多次反复计算和网格加密的方式实现了二维自适应上限有限元分析并编制了计算程序。利用条形基础地基极限承载力课题,从上限解精度和网格加密形态方面验证了该程序的有效性。针对浅埋隧道掌子面稳定性问题,展开多参数条件下的自适应上限有限元计算,分析了网格加密过程中单元总数与上限解精度的关系,列出不同隧道埋深和内摩擦角对应的隧道掌子面稳定性临界值的上限解,揭示出掌子面稳定性变化规律及精细化的破坏模式。 展开更多
关键词 浅埋隧道 掌子面稳定性 上限有限元 6节点三角形单元 破坏模式 网格自适应
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实时市场中电价多解的判定机理 被引量:3
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作者 刘畅 冯冬涵 方陈 《电力系统自动化》 EI CSCD 北大核心 2020年第1期43-52,共10页
电价多解情况的出现将为实时市场的出清带来困难,有必要从理论上对其发生条件进行研究,并建立高效判定方法以提高实时定价效率。文中对节点电价多解情况的判定机理进行了深入分析和研究,基于市场出清问题的物理特性和数学特征,提出了退... 电价多解情况的出现将为实时市场的出清带来困难,有必要从理论上对其发生条件进行研究,并建立高效判定方法以提高实时定价效率。文中对节点电价多解情况的判定机理进行了深入分析和研究,基于市场出清问题的物理特性和数学特征,提出了退化、对偶问题多解与节点电价多解三者之间明确而严格的数学关系,基于所获判定机理建立了电价多解情况的完整有效判定流程,最终利用算例进行了判定方法对比以及有效性与适应性验证。 展开更多
关键词 节点电价 退化 对偶问题多解 电价多解 判定流程
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Flory-Huggins格子上的混合亥氏函数模型 被引量:3
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作者 施云海 刘洪来 胡英 《化工学报》 EI CAS CSCD 北大核心 1995年第6期641-648,共8页
在Florg-Huggins格子中,引入有效的链插入几率表达过量熵,以Wohl式表达过量内能,建立了多元系链状高分子溶液的分子热力学模型.二元系的计算结果表明:在r_1=1,r_2=1~10000条件下,该模型比Freed理论更接近于计算机模拟结果;在其它条件下... 在Florg-Huggins格子中,引入有效的链插入几率表达过量熵,以Wohl式表达过量内能,建立了多元系链状高分子溶液的分子热力学模型.二元系的计算结果表明:在r_1=1,r_2=1~10000条件下,该模型比Freed理论更接近于计算机模拟结果;在其它条件下,两者基本吻合.Flory-Huggins理论因引入平均场近似,结果与之相差甚远.本文模型不仅能够描述常见的三元系统液液平衡,而且能描述三元系环形液液平衡曲线. 展开更多
关键词 高分子溶液 分子热力学 F-H格子 混合亥氏函数
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客车侧翻一步碰撞算法中初始解预测方法的研究 被引量:2
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作者 王童 那景新 张苹苹 《汽车工程》 EI CSCD 北大核心 2015年第8期892-896,共5页
在作者先前开发的客车侧翻一步碰撞算法的基础上,提出一种基于结构变形标准模板和节点坐标插值的初始解预测方法,以提高其计算效率。通过对12m公路客车典型车身段模型进行模拟,并与原始侧翻一步碰撞算法和侧翻试验结果对比,验证了该方... 在作者先前开发的客车侧翻一步碰撞算法的基础上,提出一种基于结构变形标准模板和节点坐标插值的初始解预测方法,以提高其计算效率。通过对12m公路客车典型车身段模型进行模拟,并与原始侧翻一步碰撞算法和侧翻试验结果对比,验证了该方法的有效性。 展开更多
关键词 客车侧翻一步碰撞算法 结构变形标准模板 节点坐标插值 初始解预测
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基于节块展开法的Jacobian-Free Newton Krylov联立求解物理-热工耦合问题 被引量:1
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作者 周夏峰 李富 郭炯 《物理学报》 SCIE EI CAS CSCD 北大核心 2016年第9期40-47,共8页
目前反应堆物理热工耦合程序通常采用固定点迭代思路,这可能导致部分工况收敛速度慢,甚至出现不收敛的现象,严重影响了计算效率.基于此,本文将高效的粗网节块展开法(NEM)与Jacobian-Free Newton-Krylov(JFNK)方法结合,成功地开发出了一... 目前反应堆物理热工耦合程序通常采用固定点迭代思路,这可能导致部分工况收敛速度慢,甚至出现不收敛的现象,严重影响了计算效率.基于此,本文将高效的粗网节块展开法(NEM)与Jacobian-Free Newton-Krylov(JFNK)方法结合,成功地开发出了一套新方法 NEM_JFNK,实现了联立求解物理热工耦合问题.首先将NEM推广到热工问题的求解,之后使用NEM来离散物理-热工耦合问题的所有控制方程,使得所有变量都能在粗网格下进行离散,从而大大减小求解问题的规模;其次将NEM离散后的方程经过某些特殊的处理,成功地嵌入JFNK的计算框架,最终开发出了基于线性预处理的NEM_JFNK,即LP_NEM_JFNK.此外,为了充分利用原有的迭代程序,避免JFNK残差方程的重新建立,本文还开发了无需重构残差方程的NEM_JFNK,即NRC_NEM_JFNK,并实现"黑箱"耦合.文中以一维中子-热工模型为例,给出LP_NEM_JFNK和NRC_NEM_JFNK数学模型,并对计算结果进行分析.结果表明:新方法无论是收敛速度还是计算效率都具有明显优势. 展开更多
关键词 节块展开法 Jacobian-Free NEWTON-KRYLOV 物理热工耦合问题 联立求解
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