《专业英语》课件Unit-36.pptx

1、TextThermodynamics is the study of thermal phenomena,the material system in equilibrium and the establishment of the nature of the relationship between energy balance,as well as the state changes,the system of academic interaction with the outside world.Engineering thermodynamics Thermodynamics is a

2、 branch of the first development of its main research in heat and mechanical energy and other energy conversion between the law and its application in mechanical engineering is an important foundation for one subject.Thermodynamics of the basic tasks of the project is:through the thermal system,heat

3、 balance,heat,and thermal processes,and working fluid。thermodynamic cycle analysis,improve and perfect heat engine,refrigerator and heat pump working cycle,to improve energy utilization and heat conversion efficiency.To this end,the basic law of thermodynamics must be based on a variety of thermodyn

4、amic properties of the process;study the thermal gas and liquid physical properties,as well as evaporation and condensation,such as phase-change rule;study analysis of solution properties is necessary for certain types of refrigerator.Modern Engineering Thermodynamics include chemical reactions such

5、 as combustion processes,such as dissolving the physical absorption or desorption chemical processes,which also involves the aspects of chemical thermodynamics of basic knowledge.TextEngineering Thermodynamics is on the macro-theory of thermal phenomena,the study is a macro,it has been summarized by

6、 numerous facts of the first law of thermodynamics,and the second law of thermodynamics third law of thermodynamics as a basis for reasoning by the material pressure,temperature,specific volume and other macro parameters and heating,cooling,expansion,contraction,such as the overall behavior of the m

7、acro-phenomena and to study the thermal process.In this way,the internal structure and material to the specific nature,as a macro-physical properties of real data to be sure,do not need to micro-structure of the material to make any assumptions,so analysis of the results of reasoning with a high deg

8、ree of reliability,and coherent.This is its unique advantages.Ancient man long ago learned to make fire and use of fire,but then pay attention to explore the hot,cold real phenomenon.However,until the end of the 17th century,people still can not correctly distinguish between temperature and heat of

9、these two basic concepts of nature.Popular at that time,said Heat and Mass Transfer under the rule,people mistakenly believe that the high temperature object is stored as a result of thermal mass number.1709 Fahrenheit temperature scale in 1714 and 1742 1745 Celsius temperature to establish the subj

10、ect to move the temperature with accepted standards.TextFollowed by calorimetry technology developed for Earth observation science and thermal testing means is provided so that thermal embarked on the path of modern experimental science.1798,Langford was observed drilling with drill barrel,the consu

11、mption of mechanical work and the result are warming bit.In 1799,the British David with two resulting in friction between the ice surface melting,which is obviously not from the Heat and Mass said,be explained.1842,Meyer made the conservation of energy theory,that heat is a form of energy can be tra

12、nsformed into mechanical energy with each other,and the air pressure from the specific heat capacity with constant volume specific heat capacity to calculate the difference between the mechanical equivalent of heat.British physicist Joule heating in the equivalent in 1840 to establish the concept in

13、 1842 measured in different ways beyond the mechanical equivalent of heat.In 1850,the experimental results of Joule has completely abandoned the scientific community,Heat and Mass said.Recognized conservation of energy can be interchangeable in the form of first law of thermodynamics for the objecti

14、ve laws of nature.Energy unit Joule is named after him.TextThermodynamics of the formation and practice at the time the production of an urgent need to find a reasonable large-scale,highly efficient heat engine-related.In 1824,the French out of the famous Kano theorem,the work specified in a given t

15、emperature range the heat engines efficiency can reach the limit,which essentially has established the second law of thermodynamics.However,by the heat and mass transfer that the impact that his methods are proven wrong.1848,British engineer Kelvin theorem formulated in accordance with Carnot thermo

16、dynamic temperature scale.In 1850 and 1851,Germany and the Clausius Kelvin has made the second law of thermodynamics,and on this basis re-prove theorems Kano.1850 1854,according to Carnot theorem Clausius proposed and developed the concept of entropy.First law of thermodynamics and second law of rec

17、ognition,for two types of perpetual motion machine make the impossible to realize the final conclusions of science,the official formation of the thermal theory of thermodynamics of macro phenomena.At the same time the formation of the Engineering Thermodynamics This technological sciences,it became

18、the study of heat engine working principle of the theoretical foundation for the internal combustion engine,steam turbine,gas turbines and jet propulsion,etc.have to make rapid progress.TextAt the same time,research in the application of thermodynamic theory of the nature of the course material,but

19、also developed the mathematical theory of thermodynamics,the various substances found in nature to reflect the corresponding thermodynamic function was studied in the phase-change material,chemical reaction and the solution properties followed by a variety of laws.1906,Germany Nernst observed phenom

20、ena and chemical reactions at low temperature found in heat theorem;in 1912,the theorem is modified into the third law of thermodynamics expression.Since the beginning of the twentieth century,on the ultra-high pressure,super-heated steam and other physical properties,and very low temperature resear

21、ch to gain new achievements.With the issue of energy,and energy of the combined cycle,a new type of composite refrigerant great research interest.Thermodynamicsn.热力学Latent heat潜热Triple point三相点Phasen.相Specific volume比体积Throttlingn.节流Staten.状态Vacuumn.真空度Workn.功Wet saturated steam湿饱和蒸汽Wet-Bulb tempera

22、ture湿球温度Working substance工质Evaporationn.汽化Systemn.系统 Boundaryn.边界 Surroundingn.外界 closed system闭口系统 open system开口系统New Words and PhrasesNotes（1）Thermodynamics is the study of thermal phenomena,the material system in equilibrium and the establishment of the nature of the relationship between energy b

23、alance,as well as the state changes,the system of academic interaction with the outside world.热力学是研究热现象中，物质系统在平衡时的性质和建立能量的平衡关系，以及状态发生变化时，系统与外界相互作用的学科。（2）Modern Engineering Thermodynamics include chemical reactions such as combustion processes,such as dissolving the physical absorption or desorption

24、chemical processes,which also involves the aspects of chemical thermodynamics of basic knowledge.现代工程热力学还包括诸如燃烧等化学反应过程，溶解吸收或解吸等物理化学过程，这就又涉及化学热力学方面的基本知识。（3）Ancient man long ago learned to make fire and use of fire,but then pay attention to explore the hot,cold real phenomenon.古代人类早就学会了取火和用火，不过后来才注意探究

25、热、冷现象的实质。（4）In 1799,the British David with two resulting in friction between the ice surface melting,which is obviously not from the Heat and Mass said,be explained.1799年，英国人戴维用两块冰相互摩擦致使表面融化，这显然无法由“热质说”得到解释。1.Heat can be transferred from a lower temperature body to a higher one.2.During a simple hea

26、ting process of atmospheric air,the specific humidity of air will keep no change.3.Its impossible for a system to output work in a constant volume process.4.From state 1 to state 2,a system undergoes a reversible process and a irreversible process separately.The entropy change from 1 to 2 in the irreversible process must be larger than that in the reversible process.5.热力学是一门研究能量储存、转换及传递的科学。6.卡诺机是低温热源和高温热源间运行效率最高的热机。7.当物质内部各点的特性参数均相同且不随时间变化时，则称系统处于热力学平衡状态。8.在给定压强下发生气化的温度称为饱和温度，压强称为给定温度下的饱和压强。Exercises（Translate the following Chinese into English,or English into Chinese）