工程熱力學(xué)EngineeringThermodynamics課件

1、 工 程 熱 力 學(xué)Engineering Thermodynamics西安建筑科技大學(xué)環(huán)境與市政工程學(xué)院 School of Municipal & Environmental Engineering Xian University of Architecture & Technology主 講 人：趙 蕾 Zhao Lei Email:教師介紹 趙 蕾, 博士，副教授, 碩士生導(dǎo)師 環(huán)境與市政工程學(xué)院Address：環(huán)境與市政工程學(xué)院實(shí)驗(yàn)教學(xué)樓206室熱工流力教研室Tel：82202185E-mail: 助教介紹Name: Address：高層研究生公寓Tel：Introduction (

2、緒論)What does thermodynamics concern?Main Contents of Engineering ThermodynamicsSome Requirements for this course Thermodynamics can be defined as a branch of science of energy.heatThermedynamispower(Greek words)熱能Thermal Energy工程熱力學(xué)是重要的技術(shù)基礎(chǔ)課0.1 What does thermodynamics concerns? (熱力學(xué)涉及哪些內(nèi)容?）Thermody

3、namics is the branch of science which studies the rule that governs the transformation of thermal energy to other forms of energy. Also it studies how to use thermal energy efficiently. 工程熱力學(xué)是一門研究熱能有效利用及熱能和其它形式能量轉(zhuǎn)換規(guī)律的科學(xué) It includes all aspects of energy and energy transformations（能量轉(zhuǎn)換）, including po

4、wer generation, refrigeration and relationships among the properties of matter.熱電廠(熱能機(jī)械能)Thermal Power Plant (Thermal Energy Mechanical Energy飛機(jī)(熱能機(jī)械能)Aeroplane (Thermal Energy Mechanical Energy汽車 (熱能機(jī)械能)Vehicle(Thermal Energy Mechanical Energy)冰箱 (機(jī)械能熱能)Refrigerator(Mechanical Energy Thermal Energy

5、 ?Why do we need to learn Engineering Thermodynamics?自然能源的種類 (Categories of natural energy resources) A.化學(xué)能（Chemical energy ）: such as : 煤炭 （coal） 石油 （crude oil） 天然氣（ natural gas ）沼氣 （firedamp, etc）. 2.自然界中的能源（Natural energy resources)B.機(jī)械能（Mechanical energy） such as: 風(fēng)力資源 （wind resources） 水力資源 （wat

6、er resources） 潮汐能 （tidal energy）, etc.C. 熱 能（ Thermal energy） such as: 太陽能（solar energy） 地?zé)崮埽╣eothermal energy）,etc.D. 原子能（Nuclear energy ）Chemical energy Thermal energyFusion or fission reactionCombustion（燃燒）directly usedMechanical energy can be used directly.（核聚變或和裂變）(2) 能源的利用（Utilization of Energ

7、y Resources ） Thermal energyNuclear energy Thermal energy indirectly used能源轉(zhuǎn)換與利用的關(guān)系(Relationship between energy transformation and utilization) 熱 能電 能機(jī) 械 能 風(fēng)能水能化學(xué)能核能地?zé)崮芴柲芤淮文茉?天然存在)二次能源 光電轉(zhuǎn)換燃料電池光熱聚變裂變?nèi)紵囁啓C(jī)風(fēng)車熱機(jī)電動機(jī)發(fā)電機(jī)90%轉(zhuǎn)換直接利用利用生物質(zhì)90% of energy resources are transformed into thermal energy before it

8、 is used.(3) 能量轉(zhuǎn)換的共同點(diǎn)(A rule in common) Then, thermal energy is transformed into mechanical energy and used indirectly How can thermal energy be transformed into mechanical energy more efficiently?Thermal energy Mechanical energy(1) 廣泛性 universallyHeartthe heating and air-conditioning systems, the r

9、efrigerator, humidifier, the pressure cooker, the water heater, the shower, the iron and even the computer.automotive engines,rockets, jet engines,and conventional and nuclear power plans, solar collector and the design of vehicles from ordinary cars to airplanes.transformed3.熱力學(xué)的研究對象(What does Ther

10、modynamics study?)Disorganized energy organized energy （無序能） （有序能）transformed(2)代表性（ Representatively ）(3)實(shí)用性 (Practicality)4.能量轉(zhuǎn)換的一些實(shí)例(Examples of Some energy transformation application )(1)火力發(fā)電裝置 (Steam power plant)火力發(fā)電裝置基本特點(diǎn)鍋爐汽輪機(jī) 發(fā)電機(jī) 給水泵 凝汽器過熱器 1、熱源2、工質(zhì) （水，蒸汽）3、工質(zhì)狀態(tài)的變化 (加壓、加熱、膨脹做功、放熱)4、冷源Generali

11、zed Representation of Heat Engines（熱機(jī)工作原理的示意）熱 源 (Hot Reservoir)冷 源 (Cold Reservoir)How many W can be produced by absorbing QH? Is there any relationship between QH,QL and W?Is QL necessarily to be discharged to its surroundings, becoming waste energy?(2) 內(nèi)燃機(jī)裝置Internal combustion engine空氣、油廢氣吸氣壓縮點(diǎn)火膨

12、脹排氣內(nèi)燃機(jī)裝置基本特點(diǎn)1、熱源2、工質(zhì)（燃?xì)猓?、工質(zhì)經(jīng)歷狀態(tài)變化 (加壓、加熱、 膨脹做功、放熱)4、冷源 冰箱 (Refrigerator)(3)制冷空調(diào)裝置 Refrigeration System (3)制冷空調(diào)裝置 Refrigeration System 1、冷源2、工質(zhì)（制冷劑）3、循環(huán) (加壓消耗外界的功量、放熱、膨脹、吸熱)4、熱源Heat source of high temperature （高溫?zé)嵩?hot reservoir）Working substance or working medium （工作介質(zhì)）C. The change in state of wor

13、king medium （工質(zhì)的 狀態(tài)變化）D. Heat sink of low temperature （低溫冷源 cold reservoir）Thermal energy reservoir: heat source heat sink(4) Main Factors in energy transformation (能量轉(zhuǎn)換中的主要因素)0.2 研究的主要內(nèi)容 Main Contents 能量轉(zhuǎn)換的基本定律 Basic Principles of Thermodynamics熱力學(xué)第一定律 （能量守恒原理） The first law of thermodynamics (cons

14、ervation of energy principle) For example: a rock falling off a cliff human body It asserts that energy is a kind of thermodynamic property of substance. It asserts that energy has quantity as well as quality and actual process occur in the direction of decreasing quality of energy. 闡明能量不僅有量的屬性，而且也有

15、質(zhì)的屬性，過程總是朝著能量貶值的方向進(jìn)行。 For example: a cup of hot water(2) 熱力學(xué)第二定律The second law of thermodynamics （）2.工質(zhì)的性質(zhì)Properties of Working Medium (1) 理想氣體的性質(zhì) Properties of Ideal Gases (2) 水蒸氣的性質(zhì) Properties of Steam or Water Vapor (3) 濕空氣 Moist Air 3. 工程應(yīng)用 Some applications 噴管中的流動 Flow through Nozzles (2) 動力循環(huán)

16、Power Cycles (3) 制冷循環(huán)Refrigeration Cycles 主要內(nèi)容 Main Contents 第一章 熱力學(xué)基礎(chǔ)知識 第二章 理想氣體的熱力性質(zhì)第三章 熱力學(xué)第一定律第四章 理想氣體的熱力過程第五章 熱力學(xué)第二定律第七章 水蒸氣第八章 濕空氣第九章 蒸氣的流動第十章 蒸氣的動力循環(huán)第十一章 制冷循環(huán)(1) 宏觀方法 ( Classical Method) 連續(xù)體(continuum)，用宏觀物理量描述其狀態(tài)，其基本規(guī)律是無數(shù)經(jīng)驗(yàn)的總結(jié) 特點(diǎn)：可靠，普遍，不能任意推廣 經(jīng)典 （宏觀,平衡）熱力學(xué) classical (macroscopic, equilibrium)

17、 thermodynamics4.工程熱力學(xué)研究方法 (Study Method) 從微觀粒子的運(yùn)動及相互作用角度研究熱現(xiàn)象及規(guī)律。 Microscopic approach is based on the average behavior of large groups of individual particles 特點(diǎn)：揭示本質(zhì)，模型近似 微觀（統(tǒng)計(jì)）熱力學(xué) microscopic (statistical) thermodynamics(2) 微觀方法(Statistical Method)0.3 教 學(xué) 要 求 Some Requirements for this course1.

18、Clearly understand and firmly grasp of the basic principles 弄清基本概念，注意每章后的思考題2. Finish the assignment independently and submit it a week after it is assigned. 獨(dú)立完成作業(yè)，布置作業(yè)后的下周按時交 3、Explore your activeness, think hard, attend to discussion in class. 發(fā)揮主觀能動性，勤于思考，積極課堂討論，4、Solve problems as soon as it is

19、 discovered 有問題及時解決，不要拖至考試Problem Solving Technique (解題方法） (1) Problem statement （問題陳述）(2) Schematic （示意圖）(3) Assumptions （假設(shè)）(4) Physical Laws （物理定律）(5) Properties （物性參數(shù)）(6) Calculations （計(jì)算）(7) Reasoning, Verification, and Discussion （推理、證明和討論）Neatness （整潔）Organization （有條理）Completeness （完整）Visual

20、 appearance （工整） Requirements for writing form （對作業(yè)的要求）請?jiān)诓贾昧俗鳂I(yè)以后的一周內(nèi)交作業(yè)。作業(yè)得分在C及以下的同學(xué)可以重新做好之后請老師另閱。 Remark on Significant Digits （有效數(shù)字）Reporting results should be rounded to three significant digits. （結(jié)果保留三位有效數(shù)字）It is more appropriate to retain all the digits during intermediate calculations and to do the rounding in the final step. About the Exam 考試成績1、Assignment 10% (平時作業(yè)10%)2、Exercise and discussion in class 10% (課堂練習(xí)及討論參與情況 10）3、Experiment 10% (實(shí)驗(yàn)情況及報(bào)告10%)3、Final Exam 70%（ 期末考試70%）熱力學(xué)方面獲諾貝爾獎的科學(xué)家（1） J.D.范.德瓦爾斯 Johannes van der Waals (1837-1923) 荷蘭 氣體和液體狀態(tài)方程 1910年諾貝爾物理學(xué)獎熱力學(xué)