水动力学仿真AQWA教程
浮筒在海浪作用下的受力分析,AQWA软件的使用教程引受世亞太gs↓s-cHN海洋工程浮体波浪载荷计算的发展经历了一个从二维方法到三维方法维切片理论优点:可以实现得到船体剖面剪力、弯矩及湿表面的压力分布。更为重要的是,它可以对不同的波长、浪向和航速进行同样的计算,应用频谱分析方法,还可以预报船舶在给定波谱下的运动,对摇荡运动预报准确。二维切片理论劣势:平面势流理论,忽略浮体三维效应,海洋工程一般不满足细长体假设剖面载荷和脉动压力精度不够,对海洋工程两者很重要2012-6-21-3引受世亞太gs↓s-cHN解决两个问题三维浮体波浪载荷的计算:与二维势流理论不同的是,此方法把平台结构作为个整体,在平台水下部分的表面上划分网格,根据三维源汇分布理论,采用面元数值计算方法求解平台在波浪中受到的载荷。波浪力考虑二阶波浪力≯而对横撑等小尺寸构件采用 Morison方程计算载荷加载到有限元模型中,实现浮体结构强度校核2012-6-2AQWA模块介绍受世亞太gs↓s-cHN模块之间相互关系波浪力LINEWAVE通过wave传递波浪力LIBRIUMFERNAUTDRIFTASAS频域分析法时域分析法(FE model)运动响应变形响应2012-6-21-5AQWA模块介绍受世亞太gs↓s-cHNDAY1FEMGVAGSANSYS TLINEWAVE,,口口…,ASASLIBRIUMFERNAUTDRIFT(FE model)模块之间相互关系EXCEL2012-6-2QWA模块介绍流程受世亞太gs↓s-cHNDAY2FEMGVAGSANSYSLINEWAVEASASI LIBRIUMFERNAUTDRIFT■■(FE model)DAY3&DAY4EXCEL2012-6-2AQWA模块介绍受世亞太gs↓s-cHN.AQWA-L|NE:计算波浪力及结构的响应计算的水静力学程序用于3D绕射散射分析可以计算分析时考虑2阶波浪力)AQWA一FER:具有随机波的频域分析,还包括耦合缆索动力学分析功能。水动力学包括的非线性项线性化。如多个波浪状况一起计算的到统计结果。结构运动谱分析能力(波浪频率或是慢漂频率)随即波情况下悬链线张力分析AQWA一 LIBRIUM:包括停泊线的静动稳定性分析。定义平衡位置为AQWA,FER,DRFT,NAUT输出平衡位置,初步的停泊设计。可以输出结构平衡位置已经回覆力(矩)倾覆力(矩),特征值模态以及动态平衡分析,分析时候考虑风浪流联合作用。2012-6-21-8AQWA模块介绍受世亞太gs↓s-cHNAQWA一DRFT:具有随机波包括慢漂流的时域,还包括耦合缆索动力学,理论基础是二阶力,时域非线性。可以分析随机波的结构运动已经悬链线拉力的时域非线性程序AQWA-GS( GRAPHIC SUPERVISOR):图形用户界面,封装了1至5模块AQWA-WAVE:是 AQWA-LINE和ASAS间的联接程序。对于给定的波方向,周期和频率,它读取压力和运动形式的结果,并且自动地作为压力和加速度应用到 ASAS JANSYS有限元模型中2012-6-21-9典型AQWA模型受世亞太gs↓s-cHNMoored tankeSemi sub2012-6-21-10
- 2020-11-07下载
- 积分:1
Vehicle Dynamics Theory and Application
不错的汽车动力学教材,是参与汽车底盘电子开发的动力学基础。Reza n. jazarVehicle DynamicsTheory and ApplicationsSpringerReza n. jazarDept of Mechanical EngineeringManhattan collegeRiverdale. NY 10471ISBN:978-0-387-74243-4e-ISBN:978-0-387-74244-1Library of Congress Control Number: 200794219c 2008 Springer Science+ Business Media, LLCAll rights reserved. This work may not be translated or copied in whole or in part without thewritten permission of the publisher(Springer Science+Business Media, LLC, 233 SpringStreet, New York, NY 10013, USA), except for brief excerpts in connection with reviews orscholarly analysis. Use in connection with any form of information storage and retrievalelectronic adaptation, computer software, or by similar or dissimilar methodology now knownor hereafter developed is forbidden. The use in this publication of trade names, trademarksservice marks and similar terms, even if they are not identified as such, is not to be taken as anexpression of opinion as to whether or not they are subject to proprietary rightsPrinted on acid-free paper987654321springer. comKavoshmy daughter, Vazan,and my wife, MojganHappiness is when you win a race against yourselfPrefaceThis text is for engineering students. It introduces the fundamental knowledge used in vehicle dymamics. This knowledge can be utilized to developcomputer programs for analyzing the ride, handling, and optimization ofroad vehiclesVehicle dynamics has been in the engineering curriculum for more thana hundred years. Books on the subject are available, but most of themare written for specialists and are not suitable for a classroom applicationA new student, engineer, or researcher would not know where and howto start learning vehicle dynamics. So, there is a need for a textbook forbeginners. This textbook presents the fundamentals with a perspective onfuture trendsThe study of classical vehicle dynamics has its roots in the work ofgreat scientists of the past four centuries and creative engineers in thepast century who established the methodology of dynamic systems. Thedevelopment of vehicle dynamics has moved toward modeling, analysisand optimization of multi-body dynamics supported by some compliantmembers. Therefore, merging dynamics with optimization theory was anexpected development. The fast-growing capability of accurate positioninsensing, and calculations, along with intelligent computer programming arethe other important developments in vehicle dynamics. So, a textbook helpthe reader to make a computer model of vehicles, which this book doesLevel of the bookThis book has evolved from nearly a decade of research in nonlineardynamic systems and teaching courses in vehicle dynamics. It is addressedprimarily to the last year of undergraduate study and the first year graduatestudent in engineering. Hence, it is an intermediate textbook. It providesboth fundamental and advanced topics. The whole book can be coveredin two successive courses, however, it is possible to jump over some sections and cover the book in one course. Students are required to know thefundamentals of kinematics and dynamics, as well as a basic knowledge ofnumerical methodsThe contents of the book have been kept at a fairly theoretical-practicallevel. Many concepts are deeply explained and their application empha-sized, and most of the related theories and formal proofs have been explained. The book places a strong emphasis on the physical meaning andapplications of the concepts. Topics that have been selected are of highinterest in the field. An attempt has been made to expose students to aPrefacebroad range of topics and approachese There are four special chapters that are indirectly related to vehicle dy-amics: Applied Kinematics, Applied Mechanisms, Applied dynamics, andApplied vibrations. These chapters provide the related background to understand vehicle dynamics and its subsystemsOrganization of the bookThe text is organized so it can be used for teaching or for self-studyChapter 1"Fundamentals, "contains general preliminaries about tire andrim with a brief review of road vehicle classificationsPart I"One Dimensional Vehicle Dynamics, " presents forward vehicledynamics, tire dynamics, and driveline dynamics. Forward dynamics refersto weight transfer, accelerating braking, engine performance, and gear ratiodesignPart II"Vehicle Kinematics, presents a detailed discussion of vehiclemechanical subsystems such as steering and suspensionsPart IIT"Vehicle Dynamics, employs Newton and Lagrange methodsto develop the maneuvering dynamics of vehiclesPart Iv "Vehicle Vibrations, presents a detailed discussion of vehi-cle vibrations. An attempt is made to review the basic approaches anddemonstrate how a vehicle can be modeled as a vibrating multiple degreeof-freedom system. The concepts of the Newton-Euler dynamics and La-grangian method are used equally for derivation of equations of motionThe RMS optimization technique for suspension design of vehicles is intro-duced and applied to vehicle suspensions. The outcome of the optimizationtechnique is the optimal stiffness and damping for a car or suspended equipmentMethod of presentationThis book uses a fact-reason-application"structure. The "fact"is themain subject we introduce in each section. Then the reason is given as a" proof. The application of the fact is examined in some examples. Theexamplesare a very important part of the book because they show howto implement the facts. They also cover some other facts that are neededto expand the subjectPrerequisitesSince the book is written for senior undergraduate and first-year graduatelevel students of engineering, the assumption is that users are familiar withmatrix algebra as well as basic dynamics. Prerequisites are the fundamentals of kinematics, dynamics, vector analysis, and matrix theory. Thesebasics are usually taught in the first three undergraduate yearsPrefaceUnit SystemThe system of units adopted in this book is, unless otherwise stated, theinternational system of units(SI). The units of degree(deg)or radian(rad)are utilized for variables representing angular quantitiesSymbolse Lowercase bold letters indicate a vector. Vectors may be expressed inan n dimensional Euclidian space. ExamplerCUppercase bold letters indicate a dynamic vector or a dynamic matrix, such as force and moment. ExampleFo Lowercase letters with a hat indicate a unit vector. Unit vectors arenot bolded. ExampleLowercase letters with a tilde indicate a 3 x 3 skew symmetric matrixassociated to a vector. Examplea3211An arrow above two uppercase letters indicates the start and endpoints of a position vector. ExampleON = a position vector from point o to point Ne The length of a vector is indicated by a non-bold lowercase letterExampleCapital letter B is utilized to denote a body coordinate frame. ExampleB(ocgB(Oxyz)B1(o1x19121)ⅹ11PrefaceCapital letter G is utilized to denote a global, inertial, or fixed coordinate frame. ExampleG(XYZG(OXYZRight subscript on a transformation matrix indicates the departureframes. ExampleRB= transformation matrix from frame B(oxyz)Left superscript on a transformation matrix indicates the destinationframe. ExampleRBtransformation matrix from frame B(o cgz)to frame G(OxYZ)Capital letter R indicates rotation or a transformation matrix, if itshows the beginning and destination coordinate frames. Example0BSIn a0Whenever there is no sub or superscript, the matrices are shown in abracket. ExampleCOS asin a osIn aCOs O0e Left superscript on a vector denotes the frame in which the vectoris expressed. That superscript indicates the frame that the vectorbelongs to; so the vector is expressed using the unit vectors of thatEr= position vector expressed in frame G(OXYZ)Right subscript on a vector denotes the tip point that the vector isreferred to. ExamplePsition vector ofexpressed in coordinate frame G(OXYZ)Right subscript on an angular velocity vector indicates the frame thatthe angular vector is referred to. ExampleB= angularof the body coordinate frame B(oxyz)
- 2020-12-12下载
- 积分:1