Communications in Computational Physics最新文献_第3页

Solution of Inverse Geometric Problems Using a Non-Iterative MFS 使用非迭代 MFS 解决反几何问题

IF 3.7 3区物理与天体物理

Communications in Computational Physics Pub Date : 2024-04-01 DOI: 10.4208/cicp.oa-2023-0207

Andreas Karageorghis,Daniel Lesnic, Liviu Marin

引用次数: 0

Thermal Regulation in Thin Vascular Systems: A Sensitivity Analysis 薄血管系统的热调节：敏感性分析

IF 3.7 3区物理与天体物理

Communications in Computational Physics Pub Date : 2024-03-01 DOI: 10.4208/cicp.oa-2023-0166

K. B. Nakshatrala, K. Adhikari

{"title":"Thermal Regulation in Thin Vascular Systems: A Sensitivity Analysis","authors":"K. B. Nakshatrala, K. Adhikari","doi":"10.4208/cicp.oa-2023-0166","DOIUrl":"https://doi.org/10.4208/cicp.oa-2023-0166","url":null,"abstract":"One of the ways natural and synthetic systems regulate temperature is via\u0000circulating fluids through vasculatures embedded within their bodies. Because of the\u0000flexibility and availability of proven fabrication techniques, vascular-based thermal\u0000regulation is attractive for thin microvascular systems. Although preliminary designs\u0000and experiments demonstrate the feasibility of thermal modulation by pushing fluid\u0000through embedded micro-vasculatures, one has yet to optimize the performance before translating the concept into real-world applications. It will be beneficial to know\u0000how two vital design variables—host material’s thermal conductivity and fluid’s heat\u0000capacity rate—affect a thermal regulation system’s performance, quantified in terms of\u0000the mean surface temperature. This paper fills the remarked inadequacy by performing adjoint-based sensitivity analysis and unravels a surprising non-monotonic trend.\u0000Increasing thermal conductivity can either increase or decrease the mean surface temperature; the increase happens if countercurrent heat exchange—transfer of heat from\u0000one segment of the vasculature to another—is significant. In contrast, increasing the\u0000heat capacity rate will invariably lower the mean surface temperature, for which we\u0000provide mathematical proof. The reported results (a) dispose of some misunderstandings in the literature, especially on the effect of the host material’s thermal conductivity, (b) reveal the role of countercurrent heat exchange in altering the effects of design\u0000variables, and (c) guide designers to realize efficient microvascular active-cooling systems. The analysis and findings will advance the field of thermal regulation both on\u0000theoretical and practical fronts.","PeriodicalId":50661,"journal":{"name":"Communications in Computational Physics","volume":"28 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140171345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Energy-Preserving Hybrid Asymptotic Augmented Finite Volume Methods for Nonlinear Degenerate Wave Equations 非线性退化波方程的保能混合渐近增量有限体积方法

IF 3.7 3区物理与天体物理

Communications in Computational Physics Pub Date : 2024-03-01 DOI: 10.4208/cicp.oa-2023-0159

Wenju Liu,Yanjiao Zhou, Zhiyue Zhang

{"title":"Energy-Preserving Hybrid Asymptotic Augmented Finite Volume Methods for Nonlinear Degenerate Wave Equations","authors":"Wenju Liu,Yanjiao Zhou, Zhiyue Zhang","doi":"10.4208/cicp.oa-2023-0159","DOIUrl":"https://doi.org/10.4208/cicp.oa-2023-0159","url":null,"abstract":"In this paper we develop and analyze two energy-preserving hybrid asymptotic augmented finite volume methods on uniform grids for nonlinear weakly degenerate and strongly degenerate wave equations. In order to deal with the degeneracy,\u0000we introduce an intermediate point to divide the whole domain into singular subdomain and regular subdomain. Then Puiseux series asymptotic technique is used\u0000in singular subdomain and augmented finite volume scheme is used in regular subdomain. The keys of the method are the recovery of Puiseux series in singular subdomain\u0000and the appropriate combination of singular and regular subdomain by means of augmented variables associated with the singularity. Although the effect of singularity on\u0000the calculation domain is conquered by the Puiseux series reconstruction technique,\u0000it also brings difficulties to the theoretical analysis. Based on the idea of staggered\u0000grid, we overcome the difficulties arising from the augmented variables related to singularity for the construction of conservation scheme. The discrete energy conservation and convergence of the two energy-preserving methods are demonstrated successfully. The advantages of the proposed methods are the energy conservation and\u0000the global convergence order determined by the regular subdomain scheme. Numerical examples on weakly degenerate and strongly degenerate under different nonlinear\u0000functions are provided to demonstrate the validity and conservation of the proposed\u0000method. Specially, the conservation of discrete energy is also ensured by using the\u0000proposed methods for both the generalized Sine-Gordeon equation and the coefficient\u0000blow-up problem.","PeriodicalId":50661,"journal":{"name":"Communications in Computational Physics","volume":"76 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140115714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Maximum-Principle-Preserving, Steady-State-Preserving and Large Time-Stepping High-Order Schemes for Scalar Hyperbolic Equations with Source Terms 有源项的标量双曲方程的最大原则保留、稳态保留和大时间步进高阶方案

IF 3.7 3区物理与天体物理

Communications in Computational Physics Pub Date : 2024-03-01 DOI: 10.4208/cicp.oa-2023-0143

Lele Liu,Hong Zhang,Xu Qian, Songhe Song

引用次数: 0

High-Order Adaptive Dissipation Scheme Based on Vortex Recognition for Compressible Turbulence Flow 基于可压缩湍流涡流识别的高阶自适应耗散方案

IF 3.7 3区物理与天体物理

Communications in Computational Physics Pub Date : 2024-03-01 DOI: 10.4208/cicp.oa-2023-0164

Jiahong Cai,Shengye Wang, Wei Liu

{"title":"High-Order Adaptive Dissipation Scheme Based on Vortex Recognition for Compressible Turbulence Flow","authors":"Jiahong Cai,Shengye Wang, Wei Liu","doi":"10.4208/cicp.oa-2023-0164","DOIUrl":"https://doi.org/10.4208/cicp.oa-2023-0164","url":null,"abstract":"In the numerical simulation of compressible turbulence involving shock\u0000waves, accurately capturing the intricate vortex structures and robustly computing\u0000the shock wave are imperative. Employing a high-order scheme with adaptive dissipation characteristics proves to be an efficient approach in distinguishing small-scale\u0000vortex structures with precision while capturing discontinuities. However, differentiating between small-scale vortex structures and discontinuities during calculations has\u0000been a key challenge. This paper introduces a high-order adaptive dissipation central-upwind weighted compact nonlinear scheme based on vortex recognition (named as\u0000WCNS-CU-Ω), that is capable of physically distinguishing shock waves and small-scale vortex structures in the high wave number region by identifying vortices within\u0000the flow field, thereby enabling adaptive control of numerical dissipation for interpolation schemes. A variety of cases involving Euler, N-S even RANS equations are tested\u0000to verify the performance of the WCNS-CU-Ω scheme. It was found that this new\u0000scheme exhibits excellent small-scale resolution and robustness in capturing shock\u0000waves. As a result, it can be applied more broadly to numerical simulations of compressible turbulence.","PeriodicalId":50661,"journal":{"name":"Communications in Computational Physics","volume":"13 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140115709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Threshold Dislocation Dynamics Method 阈值位错动力学方法

IF 3.7 3区物理与天体物理

Communications in Computational Physics Pub Date : 2024-03-01 DOI: 10.4208/cicp.oa-2023-0188

Xiaoxue Qin,Alfonso H.W. Ngan, Yang Xiang

{"title":"A Threshold Dislocation Dynamics Method","authors":"Xiaoxue Qin,Alfonso H.W. Ngan, Yang Xiang","doi":"10.4208/cicp.oa-2023-0188","DOIUrl":"https://doi.org/10.4208/cicp.oa-2023-0188","url":null,"abstract":"The Merriman-Bence-Osher threshold dynamics method is an efficient algorithm to simulate the motion by mean curvature. It has the advantages of being easy\u0000to implement and with high efficiency. In this paper, we propose a threshold dynamics method for dislocation dynamics in a slip plane, in which the spatial operator is\u0000essentially an anisotropic fractional Laplacian. We show that this threshold dislocation dynamics method is able to give two correct leading orders in dislocation velocity,\u0000including both the $mathcal{O}(log ε)$ local curvature force and the $mathcal{O}(1)$ nonlocal force due to\u0000the long-range stress field generated by the dislocations as well as the force due to the\u0000applied stress, where $ε$ is the dislocation core size, if the time step is set to be $∆t = ε.$ This generalizes the available result of threshold dynamics with the corresponding\u0000fractional Laplacian, which is on the leading order $mathcal{O}(log∆t)$ local curvature velocity\u0000under the isotropic kernel. We also propose a numerical method based on spatial variable stretching to correct the mobility and to rescale the velocity for efficient and accurate simulations, which can be applied generally to any threshold dynamics method.\u0000We validate the proposed threshold dislocation dynamics method by numerical simulations of various motions and interaction of dislocations.","PeriodicalId":50661,"journal":{"name":"Communications in Computational Physics","volume":"106 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140115710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Positivity-Preserving and Well-Balanced High Order Compact Finite Difference Scheme for Shallow Water Equations 浅水方程的保正性和平衡良好的高阶紧凑有限差分方案

IF 3.7 3区物理与天体物理

Communications in Computational Physics Pub Date : 2024-03-01 DOI: 10.4208/cicp.oa-2023-0034

Baifen Ren,Zhen Gao,Yaguang Gu,Shusen Xie, Xiangxiong Zhang

引用次数: 0

A Second-Order Length-Preserving and Unconditionally Energy Stable Rotational Discrete Gradient Method for Oseen-Frank Gradient Flows 奥森-弗兰克梯度流的二阶保长和无条件能量稳定旋转离散梯度法

IF 3.7 3区物理与天体物理

Communications in Computational Physics Pub Date : 2024-03-01 DOI: 10.4208/cicp.oa-2023-0191

Jie Xu,Xiaotian Yang, Zhiguo Yang

引用次数: 0

A Conservative and Positivity-Preserving Method for Solving Anisotropic Diffusion Equations with Deep Learning 用深度学习求解各向异性扩散方程的保守正向保留方法

IF 3.7 3区物理与天体物理

Communications in Computational Physics Pub Date : 2024-03-01 DOI: 10.4208/cicp.oa-2023-0180

Hui Xie,Li Liu,Chuanlei Zhai,Xuejun Xu, Heng Yong

{"title":"A Conservative and Positivity-Preserving Method for Solving Anisotropic Diffusion Equations with Deep Learning","authors":"Hui Xie,Li Liu,Chuanlei Zhai,Xuejun Xu, Heng Yong","doi":"10.4208/cicp.oa-2023-0180","DOIUrl":"https://doi.org/10.4208/cicp.oa-2023-0180","url":null,"abstract":"In this paper, we propose a conservative and positivity-preserving method\u0000to solve the anisotropic diffusion equations with the physics-informed neural network\u0000(PINN). Due to the possible complicated discontinuity of diffusion coefficients, without employing multiple neural networks, we approximate the solution and its gradients by one single neural network with a novel first-order loss formulation. It is proven\u0000that the learned solution with this loss formulation only has the $mathcal{O}(varepsilon)$ flux conservation error theoretically, where the parameter $varepsilon$ is small and user-defined, while the loss\u0000formulation with the original PDE with/without flux conservation constraints may\u0000have $mathcal{O}(1)$ flux conservation error. To keep positivity with the neural network approximation, some positive functions are applied to the primal neural network solution.\u0000This loss formulation with some observation data can also be employed to identify the\u0000unknown discontinuous coefficients. Compared with the usual PINN even with the\u0000direct flux conservation constraints, it is shown that our method can significantly improve the solution accuracy due to the better flux conservation property, and indeed\u0000preserve the positivity strictly for the forward problems. It can predict the discontinuous diffusion coefficients accurately in the inverse problems setting.","PeriodicalId":50661,"journal":{"name":"Communications in Computational Physics","volume":"24 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140171344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

On the Monotonicity of $Q^2$ Spectral Element Method for Laplacian on Quasi-Uniform Rectangular Meshes 论准均匀矩形网格上拉普拉斯函数的 $Q^2$ 谱元法的单调性

IF 3.7 3区物理与天体物理

Communications in Computational Physics Pub Date : 2024-01-01 DOI: 10.4208/cicp.oa-2023-0206

Logan J. Cross, Xiangxiong Zhang

引用次数: 0