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1、Basic Thermodynamics Syllabus K. Srinivasan/IISc, Bangalore V1/17-5-04/1 BASIC THERMODYNAMICS Module 1: Fundamental Concepts definition and scope, microscopic and macroscopic approaches. Engineering Thermodynamics: Definition, some practical applications of engineering thermodynamics. System (closed
2、 system) and Control Volume (open system); Characteristics of system boundary and control surface; surroundings; fixed, moving and imaginary boundaries, examples. Thermodynamic state, state point, identification of a state through properties; definition and units, intensive and extensive various pro
3、perty diagrams, path and process, quasi-static process, cyclic and non-cyclic processes; Restrained and unrestrained processes; Thermodynamic equilibrium; definition, mechanical equilibrium; diathermic wall, thermal equilibrium, chemical equilibrium. Zeroth law of thermodynamics. Temperature as an i
4、mportant property. Module 2: Work and Heat (5) Mechanics definition of work and its limitations. Thermodynamic definition of work and heat, examples, sign convention. Displacement works at part of a system boundary and at whole of a system boundary, expressions for displacement works in various proc
5、esses through p-v diagrams. Shaft work and Electrical work. Other types of work. Examples and practical applications. Module 3: First Law of Thermodynamics (5) Statement of the First law of thermodynamics for a cycle, derivation of the First law of processes, energy, internal energy as a property, c
6、omponents of energy, thermodynamic distinction between energy and work; concept of enthalpy, definitions of specific heats at constant volume and at constant pressure. Extension of the First law to control volume; steady state-steady flow energy equation, important applications such as flow in a noz
7、zle, throttling, adiabatic mixing etc., analysis of unsteady processes, case studies. Module 4: Pure Substances compressibility chart, and other equations of state (cubic and higher orders). Pure Substances: Definition of a pure substance, phase of a substance, triple point and critical points, sub-
8、cooled liquid, saturated liquid, vapor pressure, two-phase mixture of liquid and vapor, saturated vapor and superheated vapor states of a pure substance with water as example. Representation of pure substance properties on p-T and p-V diagrams, detailed treatment of properties of steam for industria
9、l and scientific use (IAPWS-97, 95) Module 5: Basics of Energy conversion cycles (3) Devices converting heat to work and vice versa in a thermodynamic cycle Thermal reservoirs. Heat engine and a heat pump; schematic representation and efficiency and coefficient of performance. Carnot cycle. Basic Th
10、ermodynamics Syllabus K. Srinivasan/IISc, Bangalore V1/17-5-04/2 Module 6: Second Law of Thermodynamics (5) Identifications of directions of occurrences of natural processes, Offshoot of II law from the I. Kelvin-Planck statement of the Second law of Thermodynamic; Clasiuss statement of Second law o
11、f Thermodynamic; Equivalence of the two statements; Definition of Reversibility, examples of reversible and irreversible processes; factors that make a process irreversible, reversible heat engines; Evolution of Thermodynamic temperature scale. Module 7: Entropy (5) Clasius inequality; statement, pr
12、oof, application to a reversible cycle. ( QR/T) as independent of the path. Entropy; definition, a property, principle of increase of entropy, entropy as a quantitative test for irreversibility, calculation of entropy, role of T-s diagrams, representation of heat, Tds relations, Available and unavai
13、lable energy. Module 8: Availability and Irreversibility (2) Maximum work, maximum useful work for a system and a control volume, availability of a system and a steadily flowing stream, irreversibility. Second law efficiency. Basic Thermodynamics Syllabus K. Srinivasan/IISc, Bangalore V1/17-5-04/3 L
14、ecture Plan Module Learning Units Hours per topic Total Hours 1.Thermodynamics; Terminology; definition and scope, Microscopic and Macroscopic approaches. Engineering Thermodynamics; Definition, some practical applications of engineering thermodynamics. 1 2.System (closed system) and Control Volume
15、(open system); Characteristics of system boundary and control surface; surroundings; fixed, moving and imaginary boundaries, examples. 1 3.Thermodynamic state, state point, identification of a state through properties; definition and units, intensive and extensive various property diagrams, 1 4.Path
16、 and process, quasi-static process, cyclic and non- cyclic processes; Restrained and unrestrained processes; 1 1. Fundamental Concepts definition, mechanical equilibrium; diathermic wall, thermal equilibrium, chemical equilibrium. Zeroth law of thermodynamics, Temperature as an important property. 1
17、 5 6.Mechanics definition of work and its limitations. Thermodynamic definition of work and heat; examples, sign convention. 1 7.Displacement work; at part of a system boundary, at whole of a system boundary, 2 8.Expressions for displacement work in various processes through p-v diagrams. 1 2. Work
18、and Heat 9.Shaft work; Electrical work. Other types of work, examples of practical applications 1 5 10. Statement of the First law of thermodynamics for a cycle, derivation of the First law of processes, 1 11. Energy, internal energy as a property, components of energy, thermodynamic distinction bet
19、ween energy and work; concept of enthalpy, definitions of specific heats at constant volume and at constant pressure. 1 12. Extension of the First law to control volume; steady state-steady flow energy equation, 1 3. First Law of Thermo- dynamics 13. Important applications such as flow in a nozzle,
20、throttling, and adiabatic mixing etc. analysis of unsteady processes, case studies. 2 5 4. Pure Substances compressibility chart. Other equations of state (cubic and higher order) 1 16. Definition of a pure substance, phase of a substance, triple point and critical points. Sub-cooled liquid, saturat
21、ed liquid, vapour pressure, two phase mixture of liquid and vapour, saturated vapour and superheated vapour states of a pure substance 1 Steam Tables and Ideal 2 21. Clasiuss statement of Second law of Thermodynamic; Equivalence of the two statements; 1 22. Definition of Reversibility, examples of r
22、eversible and irreversible processes; factors that make a process irreversible, 1 6. Second Law of Thermo- dynamics 23. Reversible heat engines; Evolution of Thermodynamic temperature scale. 1 5 24. Clasius inequality; statement, proof, application to a reversible cycle. ( QR/T) as independent of th
23、e path. 1 25. Entropy; definition, a property, principle of increase of entropy, entropy as a quantitative test for irreversibility, 1 26. Calculation of entropy, role of T-s diagrams, representation of heat quantities; Revisit to 1st law 2 7. Entropy 27. Tds relations, Available and unavailable ene
24、rgy. 1 5 28. Maximum work, maximum useful work for a system and a control volume, 18. Availability and Irreversibility 29. Availability of a system and a steadily flowing stream, irreversibility. Second law efficiency 1 2 Basic thermodynamics Learning Objectives K. Srinivasan/IISc, Bangalore /V1/05-
25、07-2004/ 1 BASIC THERMODYNAMICS AIM: At the end of the course the students will be able to analyze and evaluate various thermodynamic cycles used for energy production - work and heat, within the natural limits of conversion. Learning Objectives of the Course 1.Recall 1.1Basic definitions and termin
26、ology 1.2Special definitions from the thermodynamics point of view. 1.3Why and how natural processes occur only in one direction unaided. 2.Comprehension 2.1Explain concept of property and how it defines state. 2.2How change of state results in a process? 2.3Why processes are required to build cycle
27、s? 2.4Differences between work producing and work consuming cycles. 2.5What are the coordinates on which the cycles are represented and why? 2.6How some of the work producing cycles work? 2.7Why water and steam are special in thermodynamics? 2.8Why air standard cycles are important? 2.9Evaluate the
28、performance of cycle in totality. 2.10 How to make energy flow in a direction opposite to the natural way and what penalties are to be paid? 2.11 How the concept of entropy forms the basis of explaining how well things are done? 2.12 How to gauge the quality of energy? 3.Application 3.1 Make calcula
29、tions of heat requirements of thermal power plants and IC Engines. 3.2 Calculate the efficiencies and relate them to what occurs in an actual power plant. 3.3 Calculate properties of various working substances at various states. 3.4 Determine what changes of state will result in improving the perfor
30、mance. 3.5 Determine how much of useful energy can be produced from a given thermal source. 4.Analysis 4.1 Compare the performance of various cycles for energy production. 4.2 Explain the influence of temperature limits on performance of cycles. Basic thermodynamics Learning Objectives K. Srinivasan
31、/IISc, Bangalore /V1/05-07-2004/ 2 4.3 Draw conclusions on the behavior of a various cycles operating between temperature limits. 4.4 How to improve the energy production from a given thermal source by increasing the number of processes and the limiting conditions thereof. 4.5 Assess the magnitude o
32、f cycle entropy change. 4.6 What practical situations cause deviations form ideality and how to combat them. 4.7 Why the temperature scale is still empirical? 4.8 Assess the other compelling mechanical engineering criteria that make thermodynamic possibilities a distant dream. 5.Synthesis Nil 6.Eval
33、uation 6.1. Assess which cycle to use for a given application and source of heat 6.2. Quantify the irreversibilites associated with each possibility and choose an optimal cycle. Work needed /produced References and resources: Books Authored by Van Wylen Spalding and Cole Moran and Shapiro Holman Rog
34、ers and Mayhew Wark Useful web sites (http:/) turbu.engr.ucf.edu/aim/egn3343 webbook.nist.gov/chemistry/fluid/ (gives the current world standards of properties for various fluids) www.uic.edu/mansoori/Thermodyna mic.Data.and.Property_html (gives links to all web based learning in thermodynamics) fbo
35、x.vt.edu:10021/eng/mech/scott Problems with solutions: 1. A 1-m3 tank is filled with a gas at room temperature 20 C and pressure 100 Kpa. How much mass is there if the gas is a) Air b) Neon, or c) Propane? Solution: Given: T=273K; P=100KPa; Mair=29; Mneon=20; Mpropane=44; TR MVPm * * Kgm air 19.1 29
36、3*8314 29*1*10 5 Kgmneon82. 019. 1* 29 20 Kgmpropane806. 182. 0* 20 44 2. A cylinder has a thick piston initially held by a pin as shown in fig below. The cylinder contains carbon dioxide at 200 Kpa and ambient temperature of 290 k. the metal piston has a density of 8000 Kg/m3and the atmospheric pre
37、ssure is 101 Kpa. The pin is now removed, allowing the piston to move and after a while the gas returns to ambient temperature. Is the piston against the stops? Schematic: 50 mm Pin100 mm Co2100 mm 100 mm Solution: Given: P=200kpa; 3 3 2 gas m10*7858. 01 . 0*1 . 0* 4 V: T=290 k: V piston=0.785*10-3:
38、 mpiston= 0.785*10-3*8000=6.28 kg Pressure exerted by piston = kpa7848 1 .0* 4 8 .9*28.6 2 When the metal pin is removed and gas T=290 k 3 3 2 2 m10*18. 115. 0*1 . 0* 4 v 3 3m 10*785. 0v1 kpa133 18. 1 785. 0*200 p2 Total pressure due to piston +weight of piston =101+7.848kpa =108.848 pa Conclusion:
39、Pressure is grater than this value. Therefore the piston is resting against the stops. 3. A cylindrical gas tank 1 m long, inside diameter of 20cm, is evacuated and then filled with carbon dioxide gas at 250c.To what pressure should it be charged if there should be 1.2 kg of carbon dioxide? Solution
40、: T= 298 k: m=1.2kg: Mpa15. 2 1*2 . 0* 4 298 * 44 8314 *2 . 1p 2 4. A 1-m3rigid tank with air 1 Mpa, 400 K is connected to an air line as shown in fig: the valve is opened and air flows into the tank until the pressure reaches 5 Mpa, at which point the valve is closed and the temperature is inside i
41、s 450 K. a. What is the mass of air in the tank before and after the process? b. The tank is eventually cools to room temperature, 300 K. what is the pressure inside the tank then? Solution: P=106Pa: P2=5*106 Pa: T1=400K: T2=450 k Kg72 . 8 400*8314 29*1*10 m 6 1 Kg 8 . 38 450*8314 29*10*5 m 6 2 Mpa3
42、4. 3 1 300 * 29 8314 *8 .38P 5. A hollow metal sphere of 150-mm inside diameter is weighed on a precision beam balance when evacuated and again after being filled to 875 Kpa with an unknown gas. The difference in mass is 0.0025 Kg, and the temperature is 250c. What is the gas, assuming it is a pure
43、substance? Solution: m=0.0025Kg: P=875*103 Kpa: T= 298 K 4 15. 0* 6 *10*875 298*0025. 0*8314 M 33 The gas will be helium. 6. Two tanks are connected as shown in fig, both containing water. Tank A is at 200 Kpa, =1m3 and tank B contains 3.5 Kg at 0.5 Mp, 4000C. The valve is now opened and the two com
44、e to a uniform state. Find the specific volume. Schematic: Known: Therefore it is a mixture of steam and water. V=1m3 M=2 Kg f =0.001061m 3/Kg g =0.88573 m3/Kg T=4000C m=3.5 Kg =0.61728m /Kg 3 X=0.61728*3.5= 2.16 Kg Final volume=2.16+1 =3.16 m3 Final volume=2+3.5= 5.5 Kg Final specific volume= 3.16/
45、5.5=0.5745 m3/Kg kg74. 1 5745. 0 1 minA Kg76. 3 5745. 0 16. 2 minB 7 The valve is now opened and saturated vapor flows from A to B until the pressure in B Consider two tanks, A and B, connected by a valve as shown in fig. Each has a volume of 200 L and tank A has R-12 at 25 C, 10 % liquid and 90% va
46、por by volume, while tank B is evacuated has reached that in A, at which point the valve is closed. This process occurs slowly such that all temperatures stay at 25 C throughout the process. How much has the quality changed in tank A during the process? B 200l Solution: Given R-12 P= 651.6 KPa g= 0.
47、02685 m3/Kg f = 0.763*10 -3 m3/Kg 3 10*763. 0 02. 0 02685. 0 18. 0 m = 6.704 + 26.212= 32.916 2037. 0 916.32 704. 6 x1 Amount of vapor needed to fill tank B =Kg448. 7 02685. 0 2 . 0 Reduction in mass liquid in tank A =increase in mass of vapor in B mf=26.212 7.448 =18.76 Kg This reduction of mass ma
48、kes liquid to occupy = 0.763*10-3 *18.76 m3 =0.0143 m3 Volume of vapor =0.2 0.0143 =0.1857 L Mg =Kg916.6 02685.0 1857.0 2694. 0 76.18916. 6 916. 6 x2 x. =6.6 % 8. A linear spring, F =Ks (x-x0), with spring constant Ks = 500 N/m, is stretched until it is 100 mm long. Find the required force and work
49、input. Solution: F=Ks(x-xo)x- x0= 0.1 m Ks=500 N/m F= 50 N 2 1 WFS = 2 1 *50*0.1 =2.53 9. A piston / cylinder arrangement shown in fig. Initially contains air at 150 kpa, 400 C. The setup is allowed to cool at ambient temperature of 20 C. a. Is the piston resting on the stops in the final state? What is the final pressure in the cylinder? W b. That is the specific work done by the air during the process? Schematic: 1m 1m Solution: p1= 150*103 Pa T1=673 K T2=