14th WCCM-ECCOMAS Congress最新文献_第6页

Effect of Vehicle-Bridge-Interaction on the Vibration of the Bridge 车-桥相互作用对桥梁振动的影响

14th WCCM-ECCOMAS Congress Pub Date : 1900-01-01 DOI: 10.23967/WCCM-ECCOMAS.2020.127

C. Stoura, E. Dimitrakopoulos

{"title":"Effect of Vehicle-Bridge-Interaction on the Vibration of the Bridge","authors":"C. Stoura, E. Dimitrakopoulos","doi":"10.23967/WCCM-ECCOMAS.2020.127","DOIUrl":"https://doi.org/10.23967/WCCM-ECCOMAS.2020.127","url":null,"abstract":". This paper studies the effect of vehicle-bridge interaction (VBI) on the vibration of the supporting bridge, and subsequently proposes a decoupled analysis scheme for the VBI problem with reference to high-speed railway systems. The study examines the VBI problem analytically and reveals the main coupling parameters between vehicles and bridges. It proves that, except for the stiffness ratio, the impedance ratio, deﬁned as the ratio of the vehicle’s damping and bridge’s mechanical impedance, is also a dominant coupling parameter between vehicles and bridges. Following, the study shows that VBI alters the mechanical system of the bridge via an additional damping, an additional stiffness and a modiﬁed loading term. The coupling terms (i.e., the vehicle response) appear solely in the modiﬁed loading term. Assuming small stiffness ratio, which is realistic for practical train-bridge systems, the proposed decoupling scheme eliminates the vehicle response from the bridge’s equation of motion in a systematic manner. With respect to the fully coupled system, the proposed method returns more accurate results compared to well-known decoupling methodologies, such as the moving load approximation.","PeriodicalId":148883,"journal":{"name":"14th WCCM-ECCOMAS Congress","volume":"127 19","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120935086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Numerical Simulation of Temperature-Driven Free Surface Flows, with Application to Laser Surface Melting 温度驱动自由表面流动的数值模拟及其在激光表面熔化中的应用

14th WCCM-ECCOMAS Congress Pub Date : 1900-01-01 DOI: 10.23967/WCCM-ECCOMAS.2020.245

A. Caboussat, J. Hess, A. Masserey, M. Picasso

引用次数: 0

Predicting Mud Motor Performance and Reliability with Reduced Order Modeling 用降阶模型预测泥浆马达性能和可靠性

14th WCCM-ECCOMAS Congress Pub Date : 1900-01-01 DOI: 10.23967/WCCM-ECCOMAS.2020.282

A. Kolyshkin

引用次数: 2

Geomiso TNL: A Software for Non-Linear Static T-Spline-Based Isogeometric Analysis of Complex Multi-Patch Structures 一个基于非线性静态t样条的复杂多块结构等几何分析软件

14th WCCM-ECCOMAS Congress Pub Date : 1900-01-01 DOI: 10.23967/WCCM-ECCOMAS.2020.158

P. Karakitsios, G. Karaiskos, A. Leontaris, P. Kolios

引用次数: 7

A Multiscale Approach to Friction On Surfaces of Polymeric Solids and in Bulk Polymeric Materials 高分子固体和块状高分子材料表面摩擦的多尺度研究

14th WCCM-ECCOMAS Congress Pub Date : 1900-01-01 DOI: 10.23967/WCCM-ECCOMAS.2020.027

A. Zmitrowicz

引用次数: 1

Newton-Multigrid FEM Solver for the Simulation of Quasi-Newtonian Modeling of Thixotropic Flows 触变流动准牛顿模型模拟的牛顿-多网格有限元求解器

14th WCCM-ECCOMAS Congress Pub Date : 1900-01-01 DOI: 10.23967/WCCM-ECCOMAS.2020.217

A. Ouazzi, N. Begum, S. Turek

引用次数: 5

Solution Verification Studies of a Pressure-Based Compressible Flow Solver 基于压力的可压缩流动求解器的解验证研究

14th WCCM-ECCOMAS Congress Pub Date : 1900-01-01 DOI: 10.23967/WCCM-ECCOMAS.2020.313

J. Muralha, C. Silva, L. Eça, C. Klaij

{"title":"Solution Verification Studies of a Pressure-Based Compressible Flow Solver","authors":"J. Muralha, C. Silva, L. Eça, C. Klaij","doi":"10.23967/WCCM-ECCOMAS.2020.313","DOIUrl":"https://doi.org/10.23967/WCCM-ECCOMAS.2020.313","url":null,"abstract":". Although considering the ﬂuid to be incompressible is a common and valid approximation in most hydrodynamic simulations, certain phenomena like sloshing or slamming involve compressibility effects. In order to capture such effects, the maritime CFD code ReFRESCO is being extended with a compressible ﬂow solver for the air in two-phase ﬂow simulations. The compressible Navier-Stokes equations, discretized with a cell-centered, collocated ﬁnite volume method, are solved with a pressure-based SIMPLE algorithm that is compatible with the incompressible ﬂow solver and enforces pressure-velocity-density coupling with a pressure-correction equation and an equation of state. In this paper, the compressible solver is tested for subsonic, transonic and supersonic ﬂow of an inviscid perfect gas in a channel with an arc circular bump. We conﬁrm that the pressure-based solver can indeed achieve iterative convergence to levels close to machine accuracy for all three regimes, with moderate decrease of convergence rate at higher Mach numbers and on ﬁner grids. Grid reﬁnement studies are performed to determine its accuracy and show observed orders of grid convergence between one and two for different quantities and different convection schemes, with lowest order for the supersonic regime, as expected. Finally, we notice that monotonic grid convergence can be","PeriodicalId":148883,"journal":{"name":"14th WCCM-ECCOMAS Congress","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131208842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Influence of Geometrical Properties for the Calculation of a Pressure-Free Whole Heart Geometry 几何特性对无压全心几何计算的影响

14th WCCM-ECCOMAS Congress Pub Date : 1900-01-01 DOI: 10.23967/WCCM-ECCOMAS.2020.177

J. Brenneisen, S. Schuler, E. Kovacheva, T. Gerach, O. Dössel, A. Loewe

引用次数: 1

Comparison of Different Quasi-Newton Techniques for Coupling of Black Box Solvers 黑箱求解器耦合不同拟牛顿技术的比较

14th WCCM-ECCOMAS Congress Pub Date : 1900-01-01 DOI: 10.23967/WCCM-ECCOMAS.2020.088

N. Delaissé, Toon Demeester, D. Fauconnier, J. Degroote

{"title":"Comparison of Different Quasi-Newton Techniques for Coupling of Black Box Solvers","authors":"N. Delaissé, Toon Demeester, D. Fauconnier, J. Degroote","doi":"10.23967/WCCM-ECCOMAS.2020.088","DOIUrl":"https://doi.org/10.23967/WCCM-ECCOMAS.2020.088","url":null,"abstract":". Fluid-structure interaction (FSI) problems are frequently solved using partitioned simulation techniques with black-box solvers, reusing reliable and optimized codes. These problems can principally be reduced to solving a root-ﬁnding problem. In case of strong coupling, pure Gauss-Seidel iterations between the structure and ﬂow solvers are unstable for lower modes. In these cases, quasi-Newton techniques are used, which construct an approximation of the Jacobian or its inverse by reusing information from previous iterations and time steps. Four different quasi-Newton techniques are compared: the interface quasi-Newton algorithm with an approximation for the inverse of the Jacobian from a least-squares model (IQN-ILS), the interface block quasi-Newton algorithm with approximate Jacobians from least-squares models (IBQN-LS), the interface quasi-Newton technique with multiple vector Jacobian (IQN-MVJ) and the multi-vector update quasi-Newton technique (MVQN). These coupling algorithms are differentiated based on whether the approximation of the Jacobian is performed for the entire black-box system (IQN-ILS and IQN-MVJ) or for both individual solvers (IBQN-LS and MVQN). Moreover, a distinction is made between methods which perform the approximation with either least-squares models (IQN-ILS and IBQN-LS) or multi-vector techniques (IQN-MVJ and MVQN). Their performance is compared by solving a 1D ﬂexible tube case, using the in-house coupling software CoCoNuT. Both the memory usage and number of iterations between structure and ﬂow solvers in each time step are examined. The techniques using a multi-vector approach require explicit matrix construction, so that memory requirements scale quadratically, whereas the least-squares techniques have a matrix-free implementation, resulting in linear scaling. In terms of convergence they are comparable.","PeriodicalId":148883,"journal":{"name":"14th WCCM-ECCOMAS Congress","volume":"64 5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116271065","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

The Parametric High-Fidelity-Generalized-Method-of-Cells (PHFGMC) Micromechanical Model for Compression Failure of FRP Composites 玻璃钢复合材料压缩破坏的参数化高保真广义胞元法细观力学模型

14th WCCM-ECCOMAS Congress Pub Date : 1900-01-01 DOI: 10.23967/wccm-eccomas.2020.339

I. Meshi, U. Breiman, R. Haj-Ali

{"title":"The Parametric High-Fidelity-Generalized-Method-of-Cells (PHFGMC) Micromechanical Model for Compression Failure of FRP Composites","authors":"I. Meshi, U. Breiman, R. Haj-Ali","doi":"10.23967/wccm-eccomas.2020.339","DOIUrl":"https://doi.org/10.23967/wccm-eccomas.2020.339","url":null,"abstract":". A multiscale model based on ﬁnite element (FE) and the Parametric High-Fidelity-Generalized-Method-of-Cells (PHFGMC) micromechanical model was formulated and implemented to solve the compression problem in unidirectional IM7/977-3 carbon epoxy composite. The nonlinear PHFGMC governing equations were obtained from a two-layered (local-global) virtual work principle and solved using a incremental-iterative formulation. In addition, the semi-analytical modiﬁed Lo and Chim failure criterion (based on the buckling of Timoshenko’s beam) for unidirectional ﬁber-reinforced composite materials under compression [1] was adopted and combined with the FE-PHFGMC multiscale model. In this study, the criterion was employed for the general case of a multi-axial loading state accompanied with a nonlinear polymeric matrix behavior, where the local and thus effective properties of the composite change continuously throughout the loading path. Therefore the predicted lamina strength was incrementally reevaluated. In the present model, the use of the nonlinear constitutive model Ramberg-Osgood was used for the matrix media and a linear-elastic transversely-isotropic law for the ﬁber, as common for carbon ﬁbrous composites. This extends the existing criterion to account for the material microstructure with a reﬁned parametric discretization, as well as the effect of a nonlinear constitutive law. The advantage of the proposed model is to predict the compressive damage (kink band formation and its width) and the compressive strength (within 11% of experimental data)","PeriodicalId":148883,"journal":{"name":"14th WCCM-ECCOMAS Congress","volume":"21 6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120999347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0