流体力学基础及其工程应用(英文版.原书第2版)

    书籍
    物理书籍
《流体力学基础及其工程应用(英文版.原书第2版)》涵盖了流体力学的基本原理和方程，列举了大量真实世界中的各种工程实例，通过强调物理背景，提供精彩的图片和可视化辅助手段，让学生对流体力学有一个直观的理解并认识到流体力学是如何应用于工程实践的。全书共15章，包括引言与基本概念，流体的性质，压强与流体静力学，流体运动学，质量、伯努利与能量方程，流动系统的动量分析，量纲分析与模型化，内流，流体流动的微分分析，纳维-斯托克斯方程的近似解，外流，可压缩流动，明渠流动，涡轮机械，及计算流体动力学导论。

《流体力学基础及其工程应用(英文版.原书第2版)》后附有DVD光盘，内容包括录像、CFD动画库和EES软件等丰富资源。

《流体力学基础及其工程应用(英文版.原书第2版)》可作为高等工科院校相关专业的流体力学教材，也可供相关专业科研和工程技术人员参考。

尤努斯·A.森哲尔（Yunus A.Cengel），美国内华达大学机械工程荣誉退休教授。他在土耳其伊斯坦布尔技术大学获得机械工程学士学位，在北卡罗莱纳州立大学机械工程系获得硕士和博士学位。他的研究领域是可再生能源、脱盐、可用性分析、传热强化、辐身热传递和能量储存等。1996-2000年，他担任内华达大学工业评估中心主任，带领学生到北内华达和加利福尼亚的一些生产厂家做工业评估，筹划能量储备，降低消耗，为他们提供提高生产力的报告。 森哲尔博士是被广泛使用的教科书Thermodynamics：An Engineering Approach（《热动力学：工程研究方法》第6版，2008）的作者之一，该书由麦格劳一希尔公司出版。他还是该出版社出版的另两本教科书：Heat Transfer：A PracticalApproach（《热传输：实用研究方法》第3版，2007）的作者，以及Funda—mentals of Thermal—Fluid Sciences（《热流体科学基础》第3版，2008）的作者之一。他的部分教科书已被翻译成中文、日文、韩文、西班牙文、土耳其文、意大利文和希腊文。 森哲尔博士获得了多个优秀教师奖，他还于1992年和2000年两次获得美国工程教育学会（ASEE）为优秀原创作者设立的Meriam／Wiley卓越作者奖。 森哲尔博士是内华达州的注册教授级工程师，也是美国机械工程师学会（ASME）和美国工程教育学会的会员。 约翰·M.辛巴拉（John M.Cimbala），美国宾夕法尼亚州立大学机械工程教授。他在宾夕法尼亚州立大学获得航空航天工程学士学位，在加利福尼亚理工学院获得航空硕士学位，1984年在加利福尼亚理工学院获得航空博士学位，师从AnatolRoshko教授（辛巴拉永远感激他）。他的研究领域包括实验与计算流体力学、热传输、湍流、湍流建模、室内空气质量和空气污染控制等。1993—1994年，他利用大学学术休假期间到美国宇航局（NASA）兰利研究中心从事计算流体力学和湍流建模研究工作。 辛巴拉博士是三本教科书的作者之一：Indoor Air Quality Engineering：Environmental Health and ControlofIndoor Polutants（《室内空气质量工程：健康与室内污染控制》，2003），该书由Marcel-Dekker公司出版；Essentials ofFluid Mechanics：Fundamentals and Applications（《流体力学要素：基础与应用》，2008）和Fundamentals of Thermal—Fluid Scinces（《热流体科学基础》第3版，2008），这两本书均由麦格劳-希尔公司出版。他还与别人共同编著了其他一些书，他也是数十篇期刊和会议论文的作者或共同作者。从www.mne.psu.edu／cimbala网站上可查到他更多的信息。 辛巴拉教授获得多个优秀教学奖，本书就是他热爱教学的一个见证。他是美国航空航天学会（AIAA）、美国机械工程师学会、美国工程教育学会和美国物理学会（APS）的会员。

《流体力学基础及其工程应用(英文版.原书第2版)》
前言
第1章 引言与基本概念1
1.1 引言2
1.2 不滑移条件6
1.3 流体力学简要历史7
1.4 流动分类9
1.5 系统与控制体14
1.6 量纲与单位的重要性15
1.7 工程问题数学建模21
1.8 问题求解技巧23
1.9 工程软件包25
1.10 准确度、精确度与有效数字28
小结31
参考文献31
应用聚焦：核爆炸与雨滴有什么共同点32
习题33
第2章 流体的性质37
2.1 引言38
2.2 密度与比重39

　　1-1 INTRODUCT00N
　　Mechanics is the oldest physical science that deals with both stationary andmoving bodies under the influence of forces．The branch of mechanics thatdeals with bodies at rest is called statics,while the branch that deals withbodies in motion is called dynamics．The subcategory fluid mechanics isdefined as the science that deals with the behavior of fluids at rest(fluid sta．tics)or in motion(fluid dynamics),and the interaction of fluids with solids0r other fluids at the boundaries．Fluid mechanics is also referred to as fluiddynamics by considering fluids at rest as a special case of motion wlth zerovelocity(Fig．1一l)．
　　Fluid mechanics itself is also divided into several categories．Thc study ofthe motion of fluids that can be approximated as incompressible(such as liq．uids．especially water,and gases at low speeds)is usually referred to as hydro．dynamics．A subcategory of hydrodynamics is hydraulics,whch deals withliquid flows in pipes and open channels．Gas dynamics deals with the flow offluids that undergo significant density changes,such as the flow of gasesthrough nozzles at high speeds.The category aerodynamics de:als with theflow of gases(especially air)over bodies such as aircraft,rockets,and automo．biles at high or low speeds.Some other specialized categories such as meteo rology,oceanography,and hydrology deal with naturally occurring flows．What!s a Fluid?
　　You will recall from physics that a substance exists in three primary phases:solid．1iquid,and gas．(At very high temperatures,it also exists as plasma．)A substance in the liquid or gas phase is referred to as a fluid．Distinctionbetween a solid and a fluid is made on the basis of the substance's ability toresist an applied shear(or tangential)stress that tends to change lts shape．Asolid can resist an applied shear s~ess by deforming．whereas a flMzddcfoFillS continuously under the influence of a shear stress,no matter howsmall．In solids．stress is proportional to strain,but in fluids,stress is pro．portional to strain rate．When a constant sheqr force is applied,a solid even．tually stops deforming at some fixed strain泗gIC,whereas a fluid neverstops deforming and approaches a constant rate of strain．
　　Consider a rectangular rubber block tightly placed between two plates．Asthe upper plate is pulled with a force F while the lower plate is held fixed,the rubber block deforms,as shown in Fig．1-2．The angle of deformation 0／(called the shear strain or angular displacement)increases in proportion tothe applied force F．Assuming there is no slip between the rubber and theplates．the upper surface of the rubber is displaced by an amount equal tothe displacement of the upper plate while the lower surface remams station．ary．In equilibrium,the net force acting on the upper plate In the horizontaldirection must be zero,and thus a force equal and opposite to F must beacting on the plate．This opposing force that develops at the plate-rubberinterface due to friction is expressed as F'rA,where丁is the shear stressand A is the contact area between the upper plate and the rubber．When theforce is removed,the rubber returns to its original position．This phenome．non would also be observed with other solids such as a steel block providedthat the applied force does not exceed the elastic range．If this expenmentwere repeated with a fluid(with two large parallel plates placed in a largebody of water,for example),the fluid layer in contact with the upper platewould move with the plate continuously at the velocity of the plate no mat—ter how small the force F．ThC fluid velocity would decrease with depthbecause of friction between fluid layers．reaching zero at the lower plate．
　　You will recall from statics that stress is defined as force per unit areaand is determined by dividing the force by the area upon which it acts．Thenormal component of a force acting on a surface per unit area is called thenormal stress,and the tangential component of a force acting on a surfaceper unit area is called shear stress(Fig．1—3)．In a fluid at rest．the normalstress is called pressure．A fluid at rest is at a state of zero shear stress．Wbcn the walls are removed or a liquid container is tilted．a shear developsas the fiquid moves to re—establish a horizontal free surface．
　　In a fiquid,groups of molecules can move relative to each other,but thevolume remains relatively constant because of the strong cohesive forcesbetween the molecules．As a result．a liquid takes the shape of the container itis in,and it forms a free surface in a 1arger container in a gravitationaleld．Agas,On the other hand,expands until it encounters the walls of the contmnerand fills the entire available space．This is because the gas molecules arewidely spaced,and the cohesive forces between them are very small．Unlikeliquids,a gas in an open container cannot form a free surface(Fig．1—4)．
　　Although solids and fluids are easily distinguished in most cases,this dis一血cfion is not so clear in some borderline cases．For example．asphalt appearsand behaves as a solid since it resists shear stress for short periods of time．When these forces are exerted over extended periods of time,however,theasphalt deforms slowly,behaving as a fluid．Some plastics．1ead,and slurrymixtures exhibit similar behavior．Such borderline cases are beyond the scope0f ois text．The fluids we de址wi出in this text will be clearly recognizable asfluids．
　　Intermolecular bonds are strongest in solids and weakest in gases．Onereason is that molecules in solids are closely packed together,whereas ingases they are separated by relatively large distances(Fig．1—5、．The mole．cules in a solid are arranged in a paUem that is repeated throughout．Becauseof the small distances between molecules in a solid．the attractive forces ofmolecules on each other are large and keep the molecules at fixed positions.
　　……