SYLLABUS. osmania university CHAPTER - 3 : RECIPROCATING AIR COMPRESSORS CHAPTER - 5 : HEAT EXCHANGERS

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1 i SYLLABUS osmania university UNIT - I CHAPTER - 1 : THERMODYNAMICS Concepts of System, Processes and Properties, Laws of Thermodynamics, Concept of Entropy and Clausius Inequality, Steady Flow Energy Equation for an Open System, Conditions of Reversible and Irreversible Processes, Calculations of Change in Internal Energy, Enthalpy, Entropy and Work Done. CHAPTER - 2 : IC ENGINES Working of Four Stroke and Two Stroke Petrol and Diesel Engine with p-v Diagrams, Valve Timing Diagram, Calculation of Indicated Power, Break Power, Specific Fuel Consumption, Mechanical and Thermal Efficiencies. CHAPTER - 3 : RECIPROCATING AIR COMPRESSORS Single and Multistage Compressors, Workdone, Efficiency of Multistage Compressors, Effect of Clearance Volume. UNIT - II CHAPTER - 4 : HEAT TRANSFER Basic Modes of Heat Transfer, Fourier s Law of Conduction, Newton s Law of Cooling, Stefan-Boltzmann Law of Radiation and Concept of Black Body, One Dimensional Steady State Conduction, Heat Transfer Through Plane Walls Without Heat Generation, Critical Radius of Insulation for Cylinders. CHAPTER - 5 : HEAT EXCHANGERS Classification and Application of Heat Exchangers in Industry, Derivation of LMTD in Parallel and Counter Flow Heat Exchangers and Problems.

2 ii Contents UNIT - III CHAPTER - 6 : REFRIGERATION Types of Refrigeration Systems, Air Refrigeration System, Vapor Compression System, Ammonia-Water Absorption, Refrigeration System, Thermoelectric Refrigeration System, COP and Representation Cycle on T-S and P-H Diagrams, Types and Properties of Refrigerants, Eco-Friendly Refrigerants, Introduction to Psychrometry and Psychrometry Processes. UNIT - IV CHAPTER - 7 : BASIC MANUFACTURING PROCESSES Welding, Brazing and Soldering, Brief Description of Process, Parameters and Associated Principles of Gas Welding, Arc Welding. CHAPTER - 8 : CASTING Sand Casting, Die Casting and Principles, Applications. CHAPTER - 9 : FORMING Basic Concepts of Forming Process, Rolling, Wire Drawing. CHAPTER - 10 : PRINCIPLES AND APPLICATIONS OF BASIC MACHINING PROCESS Turning, Drilling and Shaping. UNIT - V CHAPTER - 11 : BASIC LINK MECHANISM Applications of Four Bar Planar Mechanisms, Single Slider Crank Mechanisms. CHAPTER - 12 : GEARS Classifications of Gears, Nomenclature, Gear Trains, Simple, Compound, Reverted and Epi-Cycle Gear Trains. CHAPTER - 13 : BELT AND ROPE DRIVES Open and Cross Belt Drives, Length of Belt, Ratio of Tensions of Flat Belt, Condition for Maximum Power Transmission for Flat Belt.

3 elements of mechanical engineering (b.e. o.u) ii year i semester (ELECTRONICS AND COMMUNICATION ENGINEERING) CONTENTS iii 1.1 INTRODUCTION MACROSCOPIC AND MICROSCOPIC APPROACH OF THERMODYNAMIC SYSTEM Macroscopic Approach Microscopic Approach CONCEPTS OF SYSTEM, PROCESSES AND PROPERTIES Thermodynamic System Open, Closed and Isolated Systems Open System Closed System Isolated System Adiabatic and Diabatic System Homogeneous and Heterogeneous System Homogenous System Heterogenous System Thermodynamic Properties Intensive and Extensive Properties State and Path of the Thermodynamic System State of the Thermodynamic System

4 iv Contents Path of the Thermodynamic System Point and Path Function Thermodynamic Process Cyclic Process Quasi-Static Process Reversible and Irreversible Process Comparison Between Reversible and Irreversible Process Isothermal, Adiabatic, Isobaric and Isochoric Process THERMODYNAMIC EQUILIBRIUM LAWS OF THERMODYNAMICS ZEROTH TH LAW W OF THERMODYNAMICS Temperature Scales Celsius Scale Fahrenheit Scale Kelvin Scale Rankine Scale The Relation between Various Temperature Scales FIRST LAW OF THERMODYNAMICS Corollaries of First Law of Thermodynamics Corollary 1 : Internal Energy As a Property of System Corollary 2 : Conservation of Energy Corollary 3 : Perpetual Motion Machine of First Kind (PMM1) Energy Interaction Work ork Heat

5 v Comparison of Work and Heat The Ideal Gas Equation of State Specific Heats Specific Heat at Constant Pressure Specific Heat At Constant Volume Relation between Specific Heats and Gas Constant Enthalpy Calculations of Change in Internal Energy,, Enthalpy and Work Done Constant Volume (Isochoric) Process Constant Pressure (Isobaric) Process Constant Temperature (Isothermal) Process Reversible Adiabatic (Isentropic) Process Polytropic Process Steady Flow Energy Equation for an Open System Conditions for Steady Flow System Equation of Continuity Steady Flow Energy Equation (SFEE) Workdone in Flow Process SFEE For Engineering Devices Limitations of First Law of Thermodynamics SECOND LAW OF THERMODYNAMICS Terminology Used in Second Law of Thermodynamics Kelvin-Planck and Clausius Statement Kelvin-Planck Statement Clausius Statement Conditions of Reversible and Irreversible Processes Clausius Inequality Concept of Entropy Change of Entropy

6 vi Contents Entropy as a Thermodynamic Property Characteristics of Entropy Calculations of Entropy Change in Entropy for Constant Volume (Isochoric) Process Change in Entropy for Constant Pressure (Isobaric) Process Change in Entropy for Constant Temperature (Isothermal) Process Change in Entropy for Adiabatic Process Change in Entropy for Polytropic Process THIRD LAW OF THERMODYNAMICS SOLVED PROBLEMS UNIT - I [CH. - 2] ] [IC ENGINES] Short Questions and Answers INTRODUCTION Advantages of I.C Engines Over E.C Engines Applications of I.C engines CLASSIFICATION OF IC ENGINES BASIC ENGINE COMPONENTS AND NOMENCLATURE USED Engine Components Nomenclature WORKING OF IC ENGINES WITH P-V V DIAGRAMS Working of Four our-stroke Petrol (SI) Engines Working of Four Stroke Diesel Engines Working of Two wo-stroke Petrol (SI) Engines Working of Two wo-stroke Petrol Engine Two Stroke Cycle Diesel Engine p-v Diagram for Two Stroke Petrol Engine p-v Diagram for Two Stroke Diesel Engine Advantages and Disadvantages of Two wo-stroke Cycle Engines

7 vii 2.5 VALVE VE TIMING DIAGRAM GRAM Valve Timing Diagram for a Four our-stroke Petrol Engine Valve Timing Diagram for a Four our-stroke Diesel Engines ENGINE PERFORMANCE PARAMETERS Mean Effective Pressure (P m ) Indicated Power Brake Power Friction Power Specific Fuel Consumption Mechanical Efficiency Thermal Efficiency COMPARISON OF PETROL (S.I).I) AND DIESEL (C.I) ENGINE COMPARISON OF TWO-STROKE AND FOUR-STROKE I.C ENGINES SOLVED PROBLEMS Short Questions and Answers UNIT - I [CH. - 3] ] [RECIPROCATING AIR COMPRESSORS] INTRODUCTION CLASSIFICATION OF AIR COMPRESSOR CONSTRUCTION AND WORKING OPERATION OF RECIPROCATING AIR COMPRESSORS SINGLE STAGE GE RECIPROCATING AIR COMPRESSOR Workdone Without Clearance Volume Workdone When Air is Compressed Polytropically (pv n = Constant) Workdone When Air is Compressed Adiabatically (pv γ = Constant) Workdone When Air is Compressed Isothermally (pv = Constant)

8 viii Contents Efficiencies of Reciprocating Air Compressor Isothermal Efficiency Adiabatic Efficiency Mechanical Efficiency Volumetric Efficiency Effect of Clearance Volume on Workdone and Efficiency Effect of Clearance Volume on Work Done Effect of Clearance Volume on Volumetric Efficiency MULTIST TISTAGE COMPRESSION Two wo Stage Air Compressor Workdone in Multistage Compression Advantages of Multistage Compression SOLVED PROBLEMS Short Questions and Answers UNIT - II [CH. - 4] ] [HEAT TRANSFER] INTRODUCTION BASIC MODES OF HEAT T TRANSFER Conduction Convection Radiation Comparison of Conduction, Convection and Radiation FOURIER S LAW OF CONDUCTION Thermal Conductivity One Dimensional Steady State Conduction Conduction Heat Transfer Through Plane Walls Without Heat Generation

9 ix Conduction Through a Composite Wall all Conduction Through a Hollow Cylinder Analogy Between Ohm s Law and Fourier ourier s Law of Conduction NEWTON S LAW OF COOLING THERMAL RADIATION CONCEPT OF BLACK BODY STEFAN BOLTZMANN LAW CRITICAL RADIUS OF INSULATION FOR CYLINDERS SOLVED PROBLEMS Short Questions and Answers UNIT - II [CH. - 5] ] [HEAT EXCHANGERS] INTRODUCTION CLASSIFICATION AND APPLICATIONS OF HEAT T EXCHANGERS CHANGERS Classification According to Heat Transfer Process Classification According to Constructional Features Classification According to Flow Arrangement Applications of Heat Exchangers DERIVATION OF LMTD IN PARALLEL AND COUNTER FLOW HEAT EXCHANGERS Parallel Flow Heat Exchanger Counter Flow Heat Exchanger Short Questions and Answers

10 x Contents UNIT - III [CH. H. - 6] ] [REFRIGERATION REFRIGERATION] INTRODUCTION BASIC TERMINOLOGY HEAT PUMP AND REFRIGERATOR TYPES OF REFRIGERATION SYSTEMS AIR REFRIGERATION SYSTEM COP and Air Refrigeration Cycle On T-S Diagrams Air Refrigerator Working on Reversed Carnot Cycle Air Refrigerator Working on Bell-Coleman Cycle Advantages and Disadvantages of Air Refrigeration Systems VAPOUR COMPRESSION SYSTEM Essential Components of a Vapour Compression System Vapour Compression Cycle on Pressure Enthalpy (p-h) Chart Simple Vapour Compression Cycle on T-s s Diagram Vapour Compression Cycle with Dry Saturated Vapour After Compressions Vapour Compression Cycle With ith Wet Vapour After Compression Theoretical Vapour Compression Cycle with Superheated Vapour After Compression Theoretical Vapour Compression Cycle with Superheated Vapour Before Compression Theoretical Vapour Compression Cycle with Undercooling or Subcooling of Refrigerant

11 xi Factors Affecting the Performance of a Simple Vapour Compression System Effect of Suction (or) Evaporator Pressure Effect of Condenser (or) Discharge Pressure Effect of Suction Vapour Superheat Effect of Liquid Sub-Cooling Advantages and Disadvantages of Vapour Compression System VAPOUR ABSORPTION REFRIGERATION SYSTEM Simple Ammonia-Water ater Absorption Refrigeration System Practical Ammonia-Water ater Absorption System COP of an Ideal Vapour Absorption System Desirable Properties of Refrigerant-Absorbent Combination Advantages and Disadvantages of Vapour Absorption System Comparison of Vapour Compression and Vapour Absorption Systems THERMOELECTRIC REFRIGERATION SYSTEM Analysis of a Thermoelectric Refrigerator Advantages and Disadvantages of Thermoelectric Refrigeration System Applications of Thermoelectric Refrigeration System REFRIGERANTS Types of Refrigerants Primary Refrigerants Secondary Refrigerants Desirable Properties of an Ideal Refrigerants

12 xii Contents 6.10 ECO-FRIENDL -FRIENDLY REFRIGERANTS INTRODUCTION TO PSYCHROMETR CHROMETRY Psychrometry Terms erms Psychrometry Chart Psychrometry Processes Sensible Heating Sensible Cooling Humidification and Dehumidification Cooling and Dehumidification Cooling and Humidification Heating and Dehumidification Heating and Dehumidification (Adiabatic Chemical Dehumidification) Short Questions and Answers UNIT - IV [CH. - 7] ] [BASIC MANUFACTURING PROCESSES] INTRODUCTION JOINING PROCESSES WELDING Types of Welding Processes Weldments and Weldability Gas Welding Oxyacetylene Welding elding Gas Welding Equipment Principle of Oxyacetylene Welding Types of Flames

13 xiii Advantages and Disadvantages of Gas (Oxyacetylene) Welding Applications of Gas (Oxyacetylene) Welding Arc Welding elding Principle of Arc Welding Arc Welding Equipment Power Supply Source in Arc Welding Electrodes in Arc Welding elding Purpose of Flux Coated Electrodes Comparison of A.C and D.C.C Arc Welding elding Advantages and Disadvantages of Arc Welding Applications of Arc Welding Resistance Welding Advantages and Disadvantages of Welding SOLDERING AND BRAZING Soldering Soldering Accessories Advantages and Disadvantages of Soldering Applications of Soldering Comparison of Soldering and Welding elding Brazing Process of Brazing Braze Welding Advantages and Disadvantages of Brazing COMPARISON OF SOLDERING BRAZING AND WELDING Short Questions and Answers

14 xiv Contents UNIT - IV [CH. H. - 8] ] [CASTING CASTING] INTRODUCTION Definition of Casting Advantages and Disadvantages of Casting Applications of Casting Process Materials used for Casting Process CLASSIFICATION OF CASTING PROCESS SAND CASTING Sand Casting Terminology Properties of Moulding Sand Ingredients of Moulding Sand Types of Sand Casting Green Sand Moulding Dry Sand Moulding Shell Moulding Sand Casting Procedure Cores Desirable Properties of Cores Purposes of Cores Types of Cores Pattern Materials Used for Patterns atterns Requirements of a Good Patterns Functions of Pattern Types of Patterns atterns Advantages and Disadvantages of Sand Casting

15 xv 8.4 DIE CASTING Steps Involved in Die Casting (In Metal Mould) Types of Die-casting Hot Chamber Process Cold Chamber Process Advantages/Merits Die Casting Disadvantages/Demerits of Die Casting Applications of Die Casting COMPARISON BETWEEN SAND-CASTING AND DIE CASTINGS Short Questions and Answers UNIT - IV [CH. - 9] ] [FORMING FORMING] INTRODUCTION BASIC CONCEPTS OF FORMING PROCESS CLASSIFICATION OF METAL AL FORMING PROCESS Cold Working Process Advantages Disadvantages Hot Working Process Advantages Disadvantages Comparison between Hot Working and Cold Working Process ROLLING Characteristics of Rolling Process Hot Rolling Process Cold Rolling Process Roll Configurations WIRE DRAWING COMPARISON OF ROLLING AND WIRE DRAWING Short Questions and Answers

16 xvi Contents UNIT - IV [CH. H. - 10] ] [PRINCIPLES AND APPLICATIONS OF BASIC MACHINING PROCESS] INTRODUCTION LATHE Parts of a Lathe athe Classification of Lathe Lathe Machining Operations TURNING Turning Process Details/Working Principle rinciple Characteristics of Turning Process Taper Turning urning Taper Turning by a Form Tool ool Taper Turning by the Compound Rest est Method Taper Turning by Tailstock Offset Method Workpiece Geometry of Turning Process Advantages Disadvantages DRILLING Drilling Process Details / Working Principle rinciple Characteristics of Drilling Process Principal Parts of a Drill Twist Drills Classification of Drilling Machines Portable Drilling Machine Sensitive (or) Bench Drilling Machine Upright Drilling Machines Radial Drilling Machines Gang Drilling Machine Multiple Spindle Drilling Machine

17 xvii Drilling Machine Operations Drilling Reaming Boring Counter Sinking Counter Boring Spot Facing Workpiece Geometry of Drilling Process Advantages Disadvantages SHAPING Process Details / Working Principle Process Characteristics Types of Shapers Crank Shaper Geared Type Hydraulic Shaper Horizontal Shaper Vertical Shaper Travelling Head Shaper Standard (or) Plain Shaper Universal Shaper Push Type Shaper Draw Type Shaper Principal Parts of a Shaper Advantages of Shaping Disadvantages of Shaping Applications

18 xviii Contents 10.6 PLANNING Process Details/Working Principle Process Characteristics Principal Parts of a Planar Workpiece Geometry of Shaping (or) Planning Process Advantages and Disadvantages of Planning Application of Planning Comparison of Shaping and Planning Short Questions and Answers UNIT - V [CH. - 11] ] [BASIC LINK MECHANISM] INTRODUCTION BASIC CONCEPTS Kinematic Links Kinematic Pairs Constrained Motion Kinematic Chain Mechanism and Machines Mechanism and Machines Structure Inversion of Mechanism FOUR LINK MECHANISMS FOUR BAR PLANAR MECHANISM (QUADRIC CYCLE CHAIN) Grashof s Theorem Inversions of Four Bar Mechanisms Applications of Four Bar Mechanisms

19 xix 11.5 SINGLE-SLIDER CRANK MECHANISMS Inversions and Applications of Single-Slider Crank Mechanisms First Inversion Second Inversion Third Inversion of Single-Slider Crank Chain Fourth Inversion of Single-Slider Crank Chain Short Questions and Answers UNIT - V [CH. H. - 12] ] [GEARS GEARS] INTRODUCTION GEAR TOOTH TH PROFILES CLASSIFICATION OF GEARS Spur Gears Helical Gears Double Helical and Herringbone Gears Bevel Gears Worm Gears GEAR NOMENCLATURE TURE LAW OF GEARINGS GEAR TRAINS Simple Gear Train Compound Gear Train Reverted Gear Train Epi-Cycle Gear Train DIFFERENCES BETWEEN BELT DRIVES AND GEAR DRIVES SOLVED PROBLEMS Short Questions and Answers

20 xx Contents UNIT - V [CH. H. - 13] ] [BELT AND ROPE DRIVES] INTRODUCTION BELT AND ROPE DRIVES Advantages and Disadvantages of Belt Drives Types of Belts Flat Belts V-Belts Circular Belts or Rope Belt Materials OPEN AND CROSS BELT DRIVES COMPOUND BELT DRIVE VELOCITY (OR SPEED) RATIO OF A BELT T DRIVE Effect of Belt Thickness on Velocity Ratio Effect of Slip on Velocity Ratio atio Effect of Creep on Velocity Ratio Velocity Ratio of a Compound Belt Drive LENGTH TH OF BELT Length of An Open Belt Length of a Crossed Belt Drive ANGLE OF CONTACT CT Angle of Contact For Open Belt Drive Angle of Contact For Crossed Belt Drive RATIO OF TENSIONS OF FLAT T BELT POWER TRANSMITTED BY Y A BELT Centrifugal Tension Initial Tension CONDITION FOR MAXIMUM POWER TRANSMISSION FOR FLAT BELT ROPE DRIVES SOLVED PROBLEMS Short Questions and Answers EXPECTED UNIVERSITY QUESTIONS Expected University Questions with Solutions... E.1 - E.14

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