工程流體力學是工科相關(guān)專業(yè)的重要基礎(chǔ)課程。本書為適用于單學期30 ~ 40課時雙語教學及境內(nèi)、境外本科生共同學習使用的簡明教材。
本書內(nèi)容共六章，著重講述流體力學的基礎(chǔ)原理和基礎(chǔ)假設(shè)，以及怎樣應(yīng)用這些基本原理來解決實際的工程問題。第1章介紹流體力學的基本研究內(nèi)容、壓強的表示方法及流體的基本性質(zhì)，包括流體的密度、黏度、表面張力等；第2章為流體靜力學相關(guān)內(nèi)容，包括流體上的力，流體靜壓強分布，測壓管的原理與應(yīng)用，平面壁和曲面壁上的流體靜壓力以及流體的相對靜止等；第3章介紹描述流體運動的方法和相關(guān)概念，如流線、系統(tǒng)和控制體，以及如何應(yīng)用雷諾輸運定理將物理關(guān)系在系統(tǒng)和控制體間轉(zhuǎn)換；第4章介紹理想流體動力學的基礎(chǔ)方程，包括連續(xù)性方程、伯努利方程及其應(yīng)用和動量方程；第5章介紹量綱分析和相似原理的基本思想及其在設(shè)計和簡化實驗系統(tǒng)、分析實驗數(shù)據(jù)方面的優(yōu)勢；第6章為黏性不可壓縮流體的內(nèi)部流動，主要介紹實際流體的能量損失和層流及紊流狀態(tài)，其中還簡單分析了黏性流體在圓管、孔口和縫隙中的流動特點。
本書對一些問題的分析和公式推導做了適當簡化，增加了很多關(guān)于流體傳動、液壓泵、閥及液壓系統(tǒng)的案例分析和例題。特別在第6章關(guān)于實際流體的能量方程部分，重點增加了包括泵和渦輪系統(tǒng)的能量方程及系統(tǒng)功率、效率的計算，通過這些內(nèi)容向讀者展示作為機械工程師可能處理的與流體相關(guān)的問題和應(yīng)用。通過本課程的學習，對簡單的工程問題，讀者應(yīng)該能夠獨立對待解決的問題進行分析，做出適當?shù)募僭O(shè)或近似，然后運用相關(guān)的定理建立控制方程并求解，后代入數(shù)據(jù)進行計算。
本書的編者感謝華僑大學教材建設(shè)項目的支持和教學團隊各位教師的通力協(xié)作。本書由劉曉梅任主編，李洪友、林添良任副主編。編寫團隊其他成員包括
閆潔、劉晶峰、顧永華、段闖闖。
本書可作為高等院校相關(guān)專業(yè)流體力學的教材，特別適用于機械工程類專業(yè)，也可供工程技術(shù)人員參考。
由于作者水平有限，書中難免有不妥之處，懇請讀者批評指正。

Preface
Engineering fluid mechanics is an important basic course for related majors. This is a brief bilingual course matching with one-semester 30~40 class hours for both domestic and overseas under-graduates.
In this book of six chapters, we stress the governing principles, the assumptions and the method to apply the principles to the solution of practical engineering problems. In chapter 1, some fundamental aspects of fluid mechanics, pressure scales and fluid properties are introduced, including density, viscosity and surface tension. Chapter 2 introduces fluid statics, including forces on fluid, distribution of pressure in fluid at absolute and relative rest, theories and applications of manometer, hydrostatic force on a plane surface and a curved surface etc. Chapter 3 explains methods and concepts for the description of fluid motion, including streamline, system and control volume, and Reynolds transport theorem for the transformation from system to control volume. Emphasis is placed on the fundamental equations of ideal fluid dynamics in chapter 4, including the equation of continuity, the Bernoulli equation and the equation of momentum. The advantages of using dimensional analysis and similarity for planning and simplifying experiments and for organizing test data are featured in Chapter 5. Chapter 6 expands on the internal flow of viscous incompressible fluid, includes energy losses of viscous fluid flow, the flow regimes of laminar and turbulent, practical concerns such as pipe flow, orifice and nozzle flow, and narrow gap flow are also discussed in this chapter.
The analysis of some problems and derivation of formulas are appropriately simplified in this book, and there are abundant examples and exercises of fluid transmission, hydraulic pump and valves. Special attention are given to the energy equation of real fluid, calculation of power and efficiency for the systems involving pump and turbine are presented so that the readers can understand and analyze many of the practical problems encountered by the engineer. Through this course, readers should be able to analyze problems independently, make assumptions, establish equilibrium equations, substitute parameters and solve simple engineering problems by using relevant principles.
The authors are very much indebted to the textbook funding project of Huaqiao University. This book is edited by Liu Xiaomei, Li Hongyou and Lin Tianliang. Thanks to Yan Jie,