检索结果-内蒙古大学图书馆

2015 Joint International Mechanical,Electronic and Information Technology Conference(JIMET 2015)

作者： Ma Xiaodong Guo Rui Liu Rongzhong Lv Shengtao School of Mechanical Engineering Nanjing University of Science & Technology

ISBN: (纸本)9781510817982

Based on arbitrary Lagrange-Euler method, a vortex ring parachute simulation model was set up, and its inflation was studied under the condition of infinite mass and low-speed airflow. Through changing line length, canopy area and airflow velocity, the inflation processes were simulated, and the time-histories curves of projective diameter and spinning rate were obtained. The influence of structure parameters and airflow velocity on parachute motion characteristics was analyzed. The results show that the limit spinning rate of vortex ring parachute increases with the difference increase of trailing-edge pitch line and leading-edge pitch line. With smaller canopy area and larger airflow velocity, the opening time and steady time of the parachute are shorter, and the limit spinning rate is higher, which is good for inflation and improving kinematic stability.

关键词： Vortex ring parachute Inflation Opening performance Arbitrary Lagrange-Euler method fluid-structure interaction

来源：评论

学校读者我要写书评

暂无评论

Robin-Robin preconditioned Krylov methods for fluid-structure interaction problems

引用

COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING 2009年第33-36期198卷 2768-2784页

作者： Badia, Santiago Nobile, Fabio Vergara, Christian Univ Bergamo Dept Informat Technol & Math Methods I-24044 Dalmine BG Italy Univ Politecn Cataluna Int Ctr Numer Methods Engn CIMNE ES-08034 Barcelona Spain Politecn Milan Dipartimento Matemat MOX I-20133 Milan Italy

In this work, we propose a Robin-Robin preconditioner combined with Krylov iterations for the solution of the interface system arising in fluid-structure interaction (FSI) problems. It can be seen as a partitioned FSI procedure and in this respect it generalizes the ideas introduced in [S. Badia, F. Nobile, C. Vergara, J. Comput. Phys. 227 (2008) 7027-7051]. We analyze the convergence of GMRES iterations with the Robin-Robin preconditioner on a model problem and compare its efficiency with some existing algorithms. The method is shown to be very efficient for many challenging fluid-structure interaction problems, such as those characterized by a large added-mass effect or by enclosed fluids. In particular, the possibility to solve balloon-type problems without any special treatment makes this algorithm very appealing compared to the computationally intensive existing approaches. (C) 2009 Elsevier B.V. All rights reserved.

关键词： fluid-structure interaction Partitioned procedures Domain decomposition preconditioners Robin boundary conditions Added-mass effect Hemodynamics Enclosed fluid problems

来源：评论

学校读者我要写书评

暂无评论

Treatment of acoustic fluid-structure interaction by localized Lagrange multipliers and comparison to alternative interface-coupling methods

引用

COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING 2009年第9-12期198卷 986-1005页

作者： Ross, Michael R. Sprague, Michael A. Felippa, Carlos A. Park, K. C. Sandia Natl Labs Analyt Struct Dynam Dept Albuquerque NM 87185 USA Univ Calif Sch Nat Sci Merced CA 95344 USA Univ Colorado Dept Aerosp Engn Sci Boulder CO 80309 USA Univ Colorado Ctr Aerosp Struct Boulder CO 80309 USA

This paper is a sequel on the topic of localized Lagrange multipliers (LLM) for applications of fluid-structure interaction (FSI) between finite-element models of an acoustic fluid and an elastic structure. The prequel paper formulated the spatial-discretization methods. the LLM interface treatment, the time-marching partitioned analysis procedures, and the application to I D benchmark problems. Here, we expand on formulation aspects required for successful application to more realistic 2D and 3D problems. Additional topics include duality relations at the fluid-structure interface, partitioned vibration analysis, reduced-order modeling, handling Of Curved interface surfaces, and comparison of LLM with other coupling methods. Emphasis is given to non-matching fluid-structure meshes. We present benchmark examples that illustrate the benefits and drawbacks of competing interface treatments. Realistic application problems involving the seismic response of two existing dams are considered. These include 2D modal analyses of the Koyna gravity dam, transient-response analyses of that dam with and without reduced-order modeling, incorporation of nonlinear cavitation effects, and the 3D transient-response analysis of the Morrow Point arch dam. Published by Elsevier B.V.

关键词： fluid-structure interaction Partitioned analysis Reduced-order modeling Non-matching meshes Lagrange multipliers Dynamic analysis Seismic loading Modal analysis Cavitation

来源：评论

学校读者我要写书评

暂无评论

Added Mass Effects of Compressible and Incompressible Flows in fluid-structure interaction

引用

JOURNAL OF APPLIED MECHANICS-TRANSACTIONS OF THE ASME 2009年第2期76卷 021206-1-021206-7页

作者： van Brummelen, E. H. Delft Univ Technol Fac Mech Maritime & Mat Engn NL-2628 CD Delft Netherlands

The subiteration method, which forms the basic iterative procedure for solving fluid-structure-interaction problems, is based on a partitioning of the fluid-structure system into a fluidic part and a structural part. In fluid-structure interaction, on short time scales the fluid appears as an added mass to the structural operator, and the stability and convergence properties of the subiteration process depend significantly on the ratio of this apparent added mass to the actual structural mass. In the present paper, we establish that the added-mass effects corresponding to compressible and incompressible flows are fundamentally different. For a model problem, we show that on increasingly small time intervals, the added mass of a compressible flow is proportional to the length of the time interval, whereas the added mass of an incompressible flow approaches a constant. We then consider the implications of this difference in proportionality for the stability and convergence properties of the subiteration process, and for the stability and accuracy of loosely coupled staggered time-integration methods. [DOI: 10.1115/1.3059565]

关键词： fluid-structure interaction added-mass effect compressible and incompressible flow subiteration

来源：评论

学校读者我要写书评

暂无评论

A Preconditioned JFNK Algorithm Applied to Unsteady Incompressible Flow and fluid structure interaction Problems

引用

CMES-COMPUTER MODELING IN ENGINEERING & SCIENCES 2010年第1期59卷 79-105页

作者： Lucas, Peter van Zuijlen, Alexander H. Bijl, Hester Delft Univ Technol Fac Aerosp Engn NL-2600 GB Delft Netherlands

Despite the advances in computer power and numerical algorithms over the last decades, solutions to unsteady flow problems remain computing time intensive. In previous work [Lucas, P., Bijl, H., and Zuijlen, A.H. van (2010)], we have shown that a Jacobian-free Newton-Krylov (JFNK) algorithm, preconditioned with an approximate factorization of the Jacobian which approximately matches the target residual operator, enables a speed up of a factor of 10 compared to nonlinear multi-grid (NMG) for two-dimensional, large Reynolds number, unsteady flow computations. Furthermore, in [Lucas, P., Zuijlen, A.H. van, and Bijl, H. (2010)] we show that this algorithm also greatly outperforms NMG for parameter studies into the maximum aspect ratio, grid density and physical time step: speeds ups, up to a factor of 25 are achieved. The goal of this paper is to demonstrate the wider applicability of the preconditioned JFNK algorithm by studying incompressible flow and an incompressible fluid structure-interaction (FSI) case. It is shown that the preconditioned JFNK algorithm is able to tackle the stiffness induced by the low Mach regime, making it possible to apply a compressible flow solver to nearly incompressible flow. Furthermore, it is shown that the preconditioned JFNK algorithm can be readily applied to FSI problems.

关键词： Jacobian-free Newton-Krylov low Mach number unsteady flow fluid-structure interaction

来源：评论

学校读者我要写书评

暂无评论

Stable loosely-coupled-type algorithm for fluid-structure interaction in blood flow

引用

JOURNAL OF COMPUTATIONAL PHYSICS 2009年第18期228卷 6916-6937页

作者： Guidoboni, Giovanna Glowinski, Roland Cavallini, Nicola Canic, Suncica Univ Houston Dept Math Houston TX 77204 USA Univ Paris 06 Lab Jacques Louis Lions F-75005 Paris France Univ Ferrara Ctr Math Technol I-44100 Ferrara Italy

We introduce a novel loosely coupled-type algorithm for fluid-structure interaction between blood flow and thin vascular walls. This algorithm successfully deals with the difficulties associated with the "added mass effect", which is known to be the cause of numerical instabilities in fluid-structure interaction problems involving fluid and structure of comparable densities. Our algorithm is based on a time-discretization via operator splitting which is applied, in a novel way, to separate the fluid sub-problem from the structure elastodynamics sub-problem. In contrast with traditional loosely-coupled schemes, no iterations are necessary between the fluid and structure sub-problems;this is due to the fact that our novel splitting strategy uses the "added mass effect" to stabilize rather than to destabilize the numerical algorithm. This stabilizing effect is obtained by employing the kinematic lateral boundary condition to establish a tight link between the velocities of the fluid and of the structure in each sub-problem. The stability of the scheme is discussed on a simplified benchmark problem and we use energy arguments to show that the proposed scheme is unconditionally stable. Due to the crucial role played by the kinematic lateral boundary condition, the proposed algorithm is named the "kinematically coupled scheme". Published by Elsevier Inc.

关键词： fluid-structure interaction Operator splitting Added-mass effect Finite-elements methods

来源：评论

学校读者我要写书评

暂无评论

Comparison between computational fluid dynamics, fluid-structure interaction and computational structural dynamics predictions of flow-induced wall mechanics in an anatomically realistic cerebral aneurysm model

引用

INTERNATIONAL JOURNAL OF COMPUTATIONAL fluid DYNAMICS 2009年第9期23卷 649-666页

作者： Valencia, Alvaro Munoz, Francisco Araya, Sebastian Rivera, Rodrigo Bravo, Eduardo Univ Chile Dept Mech Engn Santiago Chile Inst Neurocirugia Asenjo Dept Neuroradiol Santiago Chile

Haemodynamically induced stress plays an important role in the progression and rupture of cerebral aneurysms. The current work describes computational fluid dynamics (CFD), fluid-structure interaction (FSI) and computational structural dynamics (CSD) simulations in an anatomically realistic model of a carotid artery with two saccular cerebral aneurysms in the ophthalmic region. The model was obtained from three-dimensional (3D) rotational angiographic imaging data. CFD and FSI were studied under a physiologically representative waveform of inflow. The arterial wall was assumed elastic or hyperelastic, as a 3D solid or as a shell depending on the type of modelling used. The flow was assumed to be laminar, non-Newtonian and incompressible. The CFD, FSI and CSD models were solved with the finite elements package ADINA. Predictions of velocity field and wall shear stress (WSS) on the aneurysms made using CFD and FSI were compared. The CSD model of the aneurysms using complete geometry was compared with isolated aneurysm models. Additionally, the effects of hypertensive pressure on CSD aneurysm models are also reported. The vortex structure, WSS, effective stress, strain and displacement of the aneurysm walls showed differences, depending on the type of modelling used.

关键词： cerebral aneurysm haemodynamically induced wall stress soft tissue mechanics fluid-structure interaction

来源：评论

学校读者我要写书评

暂无评论

Parametric modal analysis of the brain-CSF-skull system Influence of the fluid-structure interaction

引用

EUROPEAN JOURNAL OF COMPUTATIONAL MECHANICS 2009年第1期18卷 55-66页

作者： El Baroudi, Adil Razafimahery, Fulgence Rakotomanana, Lalaonirina R. IRMAR UMR CNRS 6625 263 Ave Gen LeclercCampus Beaulieu F-35042 Rennes France

Dynamical behavior of the head during an impact is important for analyzing the induced local damage or diffuse damage in the brain tissue. We determine in the present study the natural frequencies and the modal shapes of the system of brain, cerebro-spinal fluid and skull. Two models are presented in this work: an elastic-acoustic model assuming a rigid skull and an elastic-acoustic-elastic model assuming a deformable skull. It is shown that natural frequencies and more significantly the modal shapes are strongly influenced by the interaction between solid phases (brain and skull) and the cerebro-spinal fluid.

关键词： modal analysis cerebro-spinal fluid fluid-structure interaction

来源：评论

学校读者我要写书评

暂无评论

A numerical study of fluid-structure coupled effect of abdominal aortic aneurysm

引用

BIO-MEDICAL MATERIALS AND ENGINEERING 2015年第1_SUPPL期26卷 S245-S255页

作者： Cong, Yingbo Wang, Liya Liu, Xiao Jilin Univ Sch Mech Sci & Engn Dept Engn Mech Changchun 130022 Peoples R China Guangdong Country Garden Polytech Dept Architectural Engn Qingyuan 511510 Peoples R China

Three numerical models of an abdominal aortic aneurysm (AAA) with different geometric parameters are established in order to examine the coupled effect of the fluid-structure of AAA. The study is focused on examining the roles of the dilatation parameter and the aspect ratio of an AAA in the flow dynamic within a pulse period. The numerical results demonstrate that the vortex dominates the dynamic flow behavior within an AAA. During a pressure impulse cycle, an AAA is influenced by the entirety of the vortex, from its generation to its subsequent disappearance. As an indirect effect of the vortex dynamic acting on vessels, a series of alternate impulse responses of the wall shear stress (WSS) is generated in an AAA as eddies induced by the vortex move along the axis of the vessels, and the strength of the responses is proportional to the strength of the eddies. The alternated impulse of WSS may be one of the main influencing factors on AAA rupture. The results of this study aided in understanding the mechanisms underlying the evolutionary processes of AAAs.

关键词： Abdominal aortic aneurysm fluid-structure interaction numerical analysis geometric parameters vortex dynamic wall shear stress

来源：评论

学校读者我要写书评

暂无评论

Implosion of Longitudinally Off-Centered Cylindrical Volumes in a Confining Environment

引用

JOURNAL OF APPLIED MECHANICS-TRANSACTIONS OF THE ASME 2015年第5期82卷 051002-051002页

作者： Gupta, Sachin LeBlanc, James M. Shukla, Arun Univ Rhode Isl Dept Mech Ind & Syst Engn Dynam Photo Mech Lab Kingston RI 02881 USA Naval Undersea Warfare Ctr Div Newport Newport RI 02841 USA

A comprehensive experimental/numerical study on the implosion of longitudinally off-centered cylindrical implodable volumes was conducted within a tubular confining space. In particular, the aim of this study was to examine the changes in the implosion mechanics and in the nature of pressure waves, arising from the longitudinally off-centered location of the implodable volume. Experiments were conducted with 31.8 mm outer diameter, cylindrical aluminum 6061-T6 implodable volumes placed concentrically within the confining tube. Three longitudinal offset locations were chosen within the confining tube, such that distance from the center of the implodable volume to the center of confining tube is equal to: (a) zero, (b) 3/7 of the half-length of confining tube (L), and (c) 5 L/7. Pressure transducers mounted on the inner surface of the confining tube were used to capture the pressure waves released during the implosion event. Computational simulations were performed using a coupled Eulerian-Lagrangian scheme to explicitly model the implosion process of the tubes along with the resulting compressible fluid flow. The experiments revealed that the longitudinal asymmetric placement of the implodable volume enhances the strength of hammer pressure waves generated during the implosion process. The off-centered location of the implodable volume causes a pressure imbalance in the entire length of the confining tube. Hence, the water particle velocity shifts toward the implodable volume producing high pressure region at the end-plate near the implodable volume, while the other end-plate experiences significantly longer cavitation due to low pressure. This far end-plate cavitation duration is also found to increase with increasing longitudinal offset, even though the total combined cavitation duration at both the end-plates is approximately same for all offset locations. With high correlation observed between the experiments and simulations, computation models were further used

关键词： implosion implodable volume collapse pressure waves computational modeling fluid-structure interaction water hammer confined environment longitudinal offset

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：