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A SING ULAR PARAM ETERIZED FINITE VOLUME METHOD FOR THE ADVECTION-DIFFUSION EQUATION IN IRREGULAR GEOMETRIES
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作者 Chang Yang Meng Wu 《计算数学:英文版》 SCIE CSCD 2019年第5期579-608,共30页
Solving the advection-diffusion equation in irregular geometries is of great importance for realistic simulations. To this end, we adopt multi-patch parameterizations to describe irregular geometries. Different from t... Solving the advection-diffusion equation in irregular geometries is of great importance for realistic simulations. To this end, we adopt multi-patch parameterizations to describe irregular geometries. Different from the classical multi-patch parameterization method, C 1- continuity is introduced in order to avoid designing interface conditions between adjacent patches. However, singularities of parameterizations can’t always be avoided. Thus, in this paper, a finite volume method is proposed based on smooth multi-patch singular parameterizations. It is called a singular parameterized finite volume method. Firstly, we present a numerical scheme for pure advection equation and pure diffusion equation respectively. Secondly, numerical stability results in L2 norm show that the numerical method is not suffered from the singularities. Thirdly, the numerical method has second order accurate in L2 norm. Finally, three numerical tests in different irregular geometries are presented to show efficiency of this numerical method. 展开更多
关键词 Finite volume method Smooth multi-patch singular PARAMETERIZATIONS The ADVECTION-DIFFUSION equation IRREGULAR GEOMETRIES
Finite volume effects on the QCD chiral phase transition in the finite size de-pendent Nambu-Jona-Lasinio model
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作者 夏永辉 王庆武 +1 位作者 冯红涛 宗红石 《中国物理C:英文版》 SCIE CAS CSCD 2019年第3期43-48,共6页
The effective Lagrangian of a finite volume system should, in principle, depend on the system size. In the framework of the Nambu-Jona-Lasinio(NJL) model, by considering the influence of quark feedback on the effectiv... The effective Lagrangian of a finite volume system should, in principle, depend on the system size. In the framework of the Nambu-Jona-Lasinio(NJL) model, by considering the influence of quark feedback on the effective coupling, we obtain a modified NJL model so that its Lagrangian depends on the volume. Based on the modified NJL model, we study the influence of finite volume on the chiral phase transition at finite temperature, and find that the pseudo-critical temperature of crossover is much lower than that obtained in the normal NJL model. This clearly shows that the volume dependent effective Lagrangian plays an important role in the chiral phase transitions at finite temperature. 展开更多
关键词 CHIRAL phase TRANSITION NJL model FINITE volume effect
Numerical investigation of the effects of aquatic plants on wind-induced currents in Taihu Lake in China 预览
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作者 Tian-ping Xu Ming-liang Zhang +3 位作者 Hcng-zhi Jiang Jun Tang Hong-xing Zhang Hui-ting Qiao 《水动力学研究与进展:英文版》 SCIE EI CSCD 2019年第4期778-787,共10页
Shallow lakes are an important part of the earth's water circulation system, and many factors may impact the evolution of the lake water circulation, including the wind, the topography, the human activities, and t... Shallow lakes are an important part of the earth's water circulation system, and many factors may impact the evolution of the lake water circulation, including the wind, the topography, the human activities, and the aquatic plants. This paper proposes a depth-averaged 2-D hydrodynamic model to investigate the interaction of the wind-induced current and the aquatic plant in the lake. The model is based on the generalized shallow water equations solved by an explicit finite volume method with unstructured triangular grids. The drag force of the vegetation is considered into the momentum equations as the source term. Remote sensing techniques are applied to evaluate the aquatic vegetation in the Taihu Lake, China, based on Landsat TM satellite images. The study model is then used to simulate the characteristics of the wind-induced currents in the Taihu Lake, without and with the vegetation effects. The simulation results are in good agreement with the field measurements, demonstrating that the aquatic plants significantly affect the magnitude of the velocity and the flow circulation induced by the wind in the Taihu Lake. In addition, a sensitivity analysis reveals that the plant parameters (the density and the drag force coefficient) are significant factors influencing the velocity and the structure of the currents in the Taihu Lake. 展开更多
关键词 Finite volume method ROE SOLVER shallow lake wind-induced current AQUATIC plant
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β型斯特林发动机有限体积建模及热力学分析研究 预览
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作者 邱文会 闫春杰 王小军 《真空与低温》 2019年第3期202-208,共7页
为了研究斯特林发动机内部腔室流体流动规律,探讨不同工况对斯特林发动机做功的影响,使用基于Fluent流体计算软件的动网格模型模拟活塞和配气活塞的运动,对于回热器,采用层流流态的多孔介质模型,其他腔室使用标准k-ε模型。结果表明,在... 为了研究斯特林发动机内部腔室流体流动规律,探讨不同工况对斯特林发动机做功的影响,使用基于Fluent流体计算软件的动网格模型模拟活塞和配气活塞的运动,对于回热器,采用层流流态的多孔介质模型,其他腔室使用标准k-ε模型。结果表明,在运行周期内,腔室的局部区域存在多个涡流,这会消耗部分能量,降低热功转换效率;增加充气压力和加热器温度可以有效增加净输出功。 展开更多
关键词 斯特林发动机 动网格 有限体积 涡流
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一种不可压缩二维流动的显式逐次超松弛并行算法
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作者 张晓慧 柏君励 +1 位作者 顾解忡 马宁 《上海交通大学学报》 EI CAS CSCD 北大核心 2019年第6期681-687,共7页
提出一种有限体积显式逐次超松弛并行(FV-pSOR)算法,以提高逐次超松弛(SOR)算法求解不可压缩二维流动控制方程组离散所形成的代数方程组的效率.基于区域分解的思想,将计算域分割成4个子域,构造了离散的一般性代数方程组的显式迭代公式... 提出一种有限体积显式逐次超松弛并行(FV-pSOR)算法,以提高逐次超松弛(SOR)算法求解不可压缩二维流动控制方程组离散所形成的代数方程组的效率.基于区域分解的思想,将计算域分割成4个子域,构造了离散的一般性代数方程组的显式迭代公式并规划了迭代路径;然后,通过数值求解典型二维方腔流,验证了FV-pSOR算法的有效性.结果表明:与SOR算法相比,所提FV-pSOR算法在计算精度相当的前提下的计算效率提高了数倍. 展开更多
关键词 分组显式 逐次超松弛 并行计算 有限体积 区域分解
Hot Air Generator Using Natural Convection Flow in a Heated Channel 预览
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作者 Bushra AlGarawi Zeinebou Yahya 《能源与动力工程:英文版》 2019年第4期131-136,共6页
Hot air producing is one of the most important engineering applications in recent years.It is a technique used in various thermodynamic systems,such as home heating systems,food dryers.One of the main problems impedin... Hot air producing is one of the most important engineering applications in recent years.It is a technique used in various thermodynamic systems,such as home heating systems,food dryers.One of the main problems impeding the spread of hot air producing technology is the lack of homogeneity of the heat flow coming from hot air generators as well as an inadequate flow rate.The most of the existing hot air generators require to be supported by systems that can increase the low volumetric flow and the air temperature of these generators,through increasing the speed of the flow of air emitted or lifting the drawer Heat,which contributes to raising the overall cost.However,to improve the thermal and dynamic quality of the hot air flow produced by the generator,a numerical investigation of the free convection flow inside two different configurations is presented in this thesis.The primary objective of this work is to predict the behavior of the flow inside tow configurations,the first one consists of a vertical cylinder with heated walls,and the second configuration is an open-ended vertical cylinder with a hot disc placed at the entrance(configuration A,configuration B).This work characterizes through the examination of this flow,the variables that control an air emission with high flow rate and a high and homogeneous temperature to represent the appropriate criteria that should be respected to obtain a hot air generator overcoming the previously mentioned constraints.Furthermore;the results of this work show the influence the boundary conditions and Rayleigh number on the resulting flow. 展开更多
关键词 Hot air GENERATOR NATURAL CONVECTION vertical CHANNEL NAVIER-STOKES equations finite volume method
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基于自适应网格的急流条件下污染物输运高效高精度模拟 预览
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作者 曹引 冶运涛 +3 位作者 梁犁丽 赵红莉 蒋云钟 王浩 《水利学报》 EI CSCD 北大核心 2019年第3期388-398,共11页
为了高效准确模拟急流条件下突发水污染事件中污染物的输运规律,基于自适应网格技术构建了Godunov格式有限体积模型。模型利用自适应结构网格离散二维浅水控制方程,对水位梯度或污染物浓度梯度较大的区域进行精细网格划分,同时细化干湿... 为了高效准确模拟急流条件下突发水污染事件中污染物的输运规律,基于自适应网格技术构建了Godunov格式有限体积模型。模型利用自适应结构网格离散二维浅水控制方程,对水位梯度或污染物浓度梯度较大的区域进行精细网格划分,同时细化干湿边界区域网格。模型采用MUSCL-Hancock方法求解二维浅水控制方程,使模型具有时空二阶精度;利用HLLC格式近似Riemann解计算界面通量,对界面两侧的Riemann变量进行非负重构和局部底部高程修正以确保模型计算的和谐性和稳定性。算例验证表明:自适应网格技术可以自动识别水位梯度或污染物浓度梯度较大的区域以及干湿边界区域并细化该区域网格,保证模型模拟精度的基础上,提升模型模拟效率;该模型能够准确高效地模拟急流条件下污染物的输运过程,适用于突发水污染事件的评估、预警和应急管理。 展开更多
关键词 突发水污染 急流 污染物输移扩散 自适应结构网格 有限体积
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Chiral phase transition from the Dyson-Schwinger equations in a finite spherical volume
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作者 赵亚鹏 张瑞瑞 +1 位作者 张涵 宗红石 《中国物理C:英文版》 SCIE CAS CSCD 2019年第6期1-5,共5页
Within the framework of the Dyson-Schwinger equations and by means of Multiple Reflection Expansion,we study the effect of finite volume on the chiral phase transition in a sphere, and discuss in particular its influe... Within the framework of the Dyson-Schwinger equations and by means of Multiple Reflection Expansion,we study the effect of finite volume on the chiral phase transition in a sphere, and discuss in particular its influence on the possible location of the critical end point(CEP). According to our calculations, when we take a sphere instead of a cube, the influence of finite volume on phase transition is not as significant as previously calculated. For instance,as the radius of the spherical volume decreases from infinite to 2 fm, the critical temperature T c, at zero chemical potential and finite temperature, drops only slightly. At finite chemical potential and finite temperature, the location of CEP shifts towards smaller temperature and higher chemical potential, but the amplitude of the variation does not exceed 20%. As a result, we find that not only the size of the volume but also its shape have a considerable impact on the phase transition. 展开更多
关键词 FINITE VOLUME effects Dyson-Schwinger EQUATIONS CHIRAL PHASE TRANSITION
A 3D Nonhydrostatic Compressible Atmospheric Dynamic Core by Multi-moment Constrained Finite Volume Method 预览
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作者 Qingchang QIN Xueshun SHEN +3 位作者 Chungang CHEN Feng XIAO Yongjiu DAI Xingliang LI 《大气科学进展:英文版》 SCIE CAS CSCD 2019年第10期1129-1142,共14页
A 3D compressible nonhydrostatic dynamic core based on a three-point multi-moment constrained finite-volume (MCV) method is developed by extending the previous 2D nonhydrostatic atmospheric dynamics to 3D on a terrain... A 3D compressible nonhydrostatic dynamic core based on a three-point multi-moment constrained finite-volume (MCV) method is developed by extending the previous 2D nonhydrostatic atmospheric dynamics to 3D on a terrainfollowing grid. The MCV algorithm defines two types of moments: the point-wise value (PV) and the volume-integrated average (VIA). The unknowns (PV values) are defined at the solution points within each cell and are updated through the time evolution formulations derived from the governing equations. Rigorous numerical conservation is ensured by a constraint on the VIA moment through the flux form formulation. The 3D atmospheric dynamic core reported in this paper is based on a three-point MCV method and has some advantages in comparison with other existing methods, such as uniform third-order accuracy, a compact stencil, and algorithmic simplicity. To check the performance of the 3D nonhydrostatic dynamic core, various benchmark test cases are performed. All the numerical results show that the present dynamic core is very competitive when compared to other existing advanced models, and thus lays the foundation for further developing global atmospheric models in the near future. 展开更多
关键词 multi-moment CONSTRAINED FINITE-VOLUME method NONHYDROSTATIC dynamic core topography height-based terrain-following coordinate
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A monotone finite volume method for time fractional Fokker-Planck equations
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作者 Yingjun Jiang Xuejun Xu 《中国科学:数学英文版》 SCIE CSCD 2019年第4期783-794,共12页
We develop a monotone finite volume method for the time fractional Fokker-Planck equations and theoretically prove its unconditional stability. We show that the convergence rate of this method is of order 1 in the spa... We develop a monotone finite volume method for the time fractional Fokker-Planck equations and theoretically prove its unconditional stability. We show that the convergence rate of this method is of order 1 in the space and if the space grid becomes suffciently fine, the convergence rate can be improved to order 2.Numerical results are given to support our theoretical findings. One characteristic of our method is that it has monotone property such that it keeps the nonnegativity of some physical variables such as density, concentration,etc. 展开更多
关键词 time FRACTIONAL FOKKER-PLANCK EQUATIONS FINITE volume methods MONOTONE CONVERGENCE
A FINITE VOLUME SEMI-IMPLICIT SEMI-LAGRANGIAN SCHEME ON THE YIN-YANG MESH
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作者 刘宇迪 李大伟 《热带气象学报:英文版》 SCIE 2019年第3期373-384,共12页
Designed for grid point systems, the traditional semi-Lagrangian semi-implicit scheme is not mass-conserving and can lead to significant solution errors. In the present study, a finite-volume semi-Lagrangian semi-impl... Designed for grid point systems, the traditional semi-Lagrangian semi-implicit scheme is not mass-conserving and can lead to significant solution errors. In the present study, a finite-volume semi-Lagrangian semi-implicit scheme(hereafter 'FVSLSI') is designed for the Yin-Yang mesh and tested in a barotropic shallow water model in the spherical coordinate system. Three test cases, i.e. the advection of a solid body, a steady state nonlinear zonal geostrophic flow and the deformation flow, are simulated to compare the performance of the FVSLSI with that of the traditional semi-Lagrangian scheme(hereafter 'SL') from perspectives of shape preservation, mass conservation,normalized bias, and convergence rate. Results indicate that the FVSLSI performs better than the SL in mass conservation and shape preservation. The bias by the FVSLSI is smaller than that by the SL, while the rate of convergence by the FVSLSI is larger than that by the SL. The FVSLSI also allows large time step. Therefore, the FVSLSI is suggested to be distributed to communities that are developing atmospheric/oceanic models. 展开更多
关键词 SEMI-IMPLICIT SCHEME SEMI-LAGRANGIAN SCHEME mass-conservative SCHEME YIN-YANG MESH finite volume
An improved semi-implicit direct kinetics method for transient analysis of nuclear reactors 预览
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作者 Roozbeh Vadi Kamran Sepanloo 《核技术:英文版》 SCIE CAS CSCD 2019年第11期108-126,共19页
Semi-implicit direct kinetics(SIDK)is an innovative method for the temporal discretization of neutronic equations proposed by J.Banfield.The key approximation of the SIDK method is to substitute a timeaveraged quantit... Semi-implicit direct kinetics(SIDK)is an innovative method for the temporal discretization of neutronic equations proposed by J.Banfield.The key approximation of the SIDK method is to substitute a timeaveraged quantity for the fission source term in the delayed neutron differential equations.Hence,these equations are decoupled from prompt neutron equations and an explicit analytical representation of precursor groups is obtained,which leads to a significant reduction in computational cost.As the fission source is not known in a time step,the original study suggested using a constant quantity pertaining to the previous time step for this purpose,and a reduction in the size of the time step was proposed to lessen the imposed errors.However,this remedy notably diminishes the main advantage of the SIDK method.We discerned that if the original method is properly introduced into the algorithm of the point-implicit solver along with some modifications,the mentioned drawbacks will be mitigated adequately.To test this idea,a novel multigroup,multi-dimensional diffusion code using the finitevolume method and a point-implicit solver is developed which works in both transient and steady states.In addition to the SIDK,two other kinetic methods,i.e.,direct kinetics and higher-order backward discretization,are programmed into the diffusion code for comparison with the proposed model.The final code is tested at different conditions of two well-known transient benchmark problems.Results indicate that while the accuracy of the improved SIDK is closely comparable with the best available kinetic methods,it reduces the total time required for computation by up to 24%. 展开更多
关键词 Nuclear KINETICS SEMI-IMPLICIT DIRECT KINETICS HIGHER-ORDER backward DISCRETIZATION Finite volume Point-implicit SOLVER
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具有自调节通风性能的大型永磁同步发电机内流热特性数值研究 预览
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作者 朱敏 丁树业 +1 位作者 江欣 刘玮 《南京师范大学学报:工程技术版》 CAS 2019年第1期1-7,共7页
为了探究具有自调节通风功能的结构紧凑型大型永磁同步发电机内部流体流变特性及温升分布规律,以一台6 MW永磁同步发电机为例,基于电机学和数值传热学理论,结合流-热耦合机理,根据电机实际冷却结构选择一个周期作为求解域,建立三维流体... 为了探究具有自调节通风功能的结构紧凑型大型永磁同步发电机内部流体流变特性及温升分布规律,以一台6 MW永磁同步发电机为例,基于电机学和数值传热学理论,结合流-热耦合机理,根据电机实际冷却结构选择一个周期作为求解域,建立三维流体场与温度场耦合分析数学模型及物理模型.采用有限体积元法对永磁同步电机三维温度场进行数值研究,对发电机定转子铁心、定子绕组与绝缘以及永磁体的温升分布特性进行详细分析.通过与电机绝缘温升限值的对比分析,验证了其求解方法的合理性以及计算结果的准确性,为永磁同步发电机温升的计算及通风结构的设计提供参考依据. 展开更多
关键词 永磁同步发电机 流-热耦合 三维温度场 有限体积元 数值计算
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坝体溃决过程与溃坝洪水演进耦合数值模拟 预览 被引量:3
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作者 姜治兵 崔丹 程子兵 《长江科学院院报》 CSCD 北大核心 2018年第5期63-67,共5页
研究坝体的溃决过程与溃坝洪水演进对于处置由溃坝引起的洪水灾害、提升水利安全具有重要的意义。鉴于目前大多模型均将坝体溃决过程与溃坝洪水演进分别进行模拟,不能反映土体与水流相互耦合的特点,模拟结果精度有限。基于对土体有限抗... 研究坝体的溃决过程与溃坝洪水演进对于处置由溃坝引起的洪水灾害、提升水利安全具有重要的意义。鉴于目前大多模型均将坝体溃决过程与溃坝洪水演进分别进行模拟,不能反映土体与水流相互耦合的特点,模拟结果精度有限。基于对土体有限抗冲能力的考虑,选取双曲线型冲蚀速率表达式描述坝体冲蚀、采用简化Bishop法搜索临界滑裂面描述溃口边坡坍塌和具有总变差不增特性的MacCormack有限体积法离散控制方程,建立了坝体溃决过程与溃坝洪水演进耦合的平面二维数值模型。实际算例表明模型合理地模拟了溃口的发展过程与洪水演进过程,在溃口急缓流转换区展现了较强稳定性,守恒性良好,可作为溃坝洪水风险评估与洪灾预报的有力工具。 展开更多
关键词 坝体溃决过程 洪水演进 数值模拟 耦合 守恒性 有限体积
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非结构有限体积耗散格式精度分析 预览
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作者 张亮 艾邦成 陈智 《兵器装备工程学报》 CAS 北大核心 2018年第11期184-193,共10页
针对耗散方程非结构网格有限体积离散,基于一维非均匀网格构造了包含相容项和高频阻尼项的耗散格式,结合模型方程研究了耗散格式的相容性条件及高频阻尼系数最优值与梯度格式的关联关系;耗散格式严格满足截断误差相容性的条件是相容项... 针对耗散方程非结构网格有限体积离散,基于一维非均匀网格构造了包含相容项和高频阻尼项的耗散格式,结合模型方程研究了耗散格式的相容性条件及高频阻尼系数最优值与梯度格式的关联关系;耗散格式严格满足截断误差相容性的条件是相容项采用代数平均加权且高频阻尼系数为1;在均匀网格条件下,可实现耗散格式最高离散精度的高频阻尼系数最优值取决于梯度格式的2阶截断误差系数;根据梯度格式的不同,高频阻尼系数最优值的取值范围在1与2之间;在非均匀网格条件下,不同梯度格式对耗散格式相容性及离散精度均有显著的影响,采用均匀网格条件下的高频阻尼系数最优值可得到更小的离散误差。 展开更多
关键词 非结构网格 有限体积 耗散格式 高频阻尼 相容性 离散误差
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A simple algorithm to improve the performance of the WENO scheme on non-uniform grids 预览
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作者 Wen-Feng Huang Yu-Xin Ren Xiong Jiang 《力学学报:英文版》 SCIE EI CAS CSCD 2018年第1期37-47,共11页
This paper presents a simple approach for improving the performance of the weighted essentially nonoscillatory (WENO) finite volume scheme on non-uniform grids. This technique relies on the reformulation of the fiftho... This paper presents a simple approach for improving the performance of the weighted essentially nonoscillatory (WENO) finite volume scheme on non-uniform grids. This technique relies on the reformulation of the fifthorder WENO-JS (WENOscheme presented by Jiang and Shu in J. Comput. Phys. 126:202–228, 1995) scheme designed on uniform grids in terms of one cell-averaged value and its left and/or right interfacial values of the dependent variable. The effect of grid non-uniformity is taken into consideration by a proper interpolation of the interfacial values. On nonuniform grids, the proposed scheme is much more accurate than the original WENO-JS scheme, which was designed for uniform grids. When the grid is uniform, the resulting scheme reduces to the original WENO-JS scheme. In the meantime, the proposed scheme is computationally much more efficient than the fifth-order WENO scheme designed specifically for the non-uniform grids. A number of numerical test cases are simulated to verify the performance of the present scheme. 展开更多
关键词 WENO SCHEME NON-UNIFORM grids Shock capturing FINITE VOLUME methods
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Numerical investigation of velocity ratio effect in combined wall and offset jet flows 预览
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作者 Nidhal Hnaien Salwa Marzouk +1 位作者 Habib Ben Aissia Jacques Jay 《水动力学研究与进展:英文版》 SCIE EI CSCD 2018年第6期1105-1119,共15页
In the present work, we propose to numerically study a combined turbulent wall and offset jet flow(this combination will be denoted WOJ). Several turbulence models were tested in this study: the standard k-ω, SST k-... In the present work, we propose to numerically study a combined turbulent wall and offset jet flow(this combination will be denoted WOJ). Several turbulence models were tested in this study: the standard k-ω, SST k-ω, standard k-ε, RNG, and realizable k-ε model. A parametric study was performed to determine the effect of offset ratio H and the velocity ratio r on the longitudinal and transverse positions of the merge point(MP), the combined point(CP), the upper vortex center(UVC) and the lower vortex center(LVC). Correlations that predict the position of these characteristic points of the WOJ flow as a function of H and r have been provided. Results show that any increase in the velocity ratio causes a displacement of the MP, CP, UVC and LVC further upstream along the longitudinal direction. Concerning the transverse positions, the increase of velocity ratio results in a deviation of the merge point(MP) and the lower vortex center(LVC) toward the strong jet(LWJ) whereas the transverse position of combined point(CP) and the upper vortex center(UVC) is almost independent of the velocity ratio. 展开更多
关键词 Finite volume COMBINED POINT MERGE POINT OFFSET JET velocity ratio
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Dynamo equation solution using Finite Volume Method for midlatitude ionosphere
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作者 Feza Arikan Umut Sezen Orhan Arikan 《大地测量与地球动力学:英文版》 2018年第6期425-431,共7页
Ionosphere is the layer of atmosphere which plays an important role both in space based navigation,positioning and communication systems and HF signals. The structure of the electron density is a function of spatio-te... Ionosphere is the layer of atmosphere which plays an important role both in space based navigation,positioning and communication systems and HF signals. The structure of the electron density is a function of spatio-temporal variables. The electrodynamic medium is also influenced with earth’s magnetic field, atmospheric chemistry and plasma flow and diffusion under earth’s gravitation. Thus, the unified dynamo equation for the ionosphere is a second order partial differential equation for quasi-static electric potential with variable spatial coefficients. In this study, the inhomogeneous and anisotropic nature of ionosphere that can be formulated as a divergence equation is solved numerically using Finite Volume Method for the first time. The ionosphere and the operators are discretized for the midlatitude region and the solution domain is investigated for Dirichlet type boundary conditions that are built in into the diffusion equation. The analysis indicates that FVM can be a powerful tool in obtaining parametric electrostatic potential distribution in ionosphere. 展开更多
关键词 IONOSPHERE FINITE VOLUME method(FVM) DYNAMO EQUATION Electric potential
苏北灌河口海域三维水动力数值模拟 预览
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作者 林伟波 魏爱泓 冒士凤 《中国农村水利水电》 北大核心 2018年第4期145-152,共8页
基于无结构网格海洋模型(FVCOM),建立了灌河口海域三维潮流数学模型。模型水平方向采用三角形网格,使得能够更好地拟合灌河口不规则岸线边界,垂向采用σ坐标。模型计算结果与实测结果吻合良好,较好地模拟了灌河口潮流场时空分布。水... 基于无结构网格海洋模型(FVCOM),建立了灌河口海域三维潮流数学模型。模型水平方向采用三角形网格,使得能够更好地拟合灌河口不规则岸线边界,垂向采用σ坐标。模型计算结果与实测结果吻合良好,较好地模拟了灌河口潮流场时空分布。水平潮流以旋转流为主,流速由北到南逐渐增大,近岸余流方向都是由北向南的沿岸流。灌河口和海州湾的水动力交换主要受潮流驱动,余流漩涡形成的主要机理可能是潮波和地形及岸线的相互作用。 展开更多
关键词 河流与海岸动力学 三维水动力模型 灌河口 有限体积
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Three-Dimensional Fluid-Structure Interaction Case Study on Cubical Fluid Cavity with Flexible Bottom 预览
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作者 Stefano Ghelardi Cesare Rizzo Diego Villa 《船舶与海洋工程学报:英文版》 CSCD 2017年第4期382-394,共13页
In this paper, we report our study on a numerical fluid-structure interaction problem originally presented by Mok et al. (2001) in two dimensions and later studied in three dimensions by Valdés Vazquez (2007), Lo... In this paper, we report our study on a numerical fluid-structure interaction problem originally presented by Mok et al. (2001) in two dimensions and later studied in three dimensions by Valdés Vazquez (2007), Lombardi (2012), and Trimarchi (2012).We focus on a 3D test case in which we evaluated the sensitivity of several input parameters on the fluid and structural results. In particular, this analysis provides a starting point from which we can look deeper into specific aspects of these simulations and analyze more realistic cases, e.g., in sails design. In this study, using the commercial software ADINATM, we addressed a well-known unsteadiness problem comprising a square box representing the fluid domain with a flexible bottom modeled with structural shell elements. We compared data from previously published work whose authors used the same numerical approach, i.e., a partitioned approach coupling a finite volume solver (for the fluid domain) and a finite element solver (for the solid domain). Specifically, we established several benchmarks and made comparisons with respect to fluid and solid meshes, structural element types, and structural damping, as well as solution algorithms. Moreover, we compared our method with a monolithic finite element solution method. Our comparisons of new and old results provide an outline of best practices for such simulations. 展开更多
关键词 fluid-structure interaction BENCHMARK FINITE volume METHOD FINITE element METHOD partitioned monolithic ADINA
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