ELEMENTS OF HEAT AND MASS TRANSFER

Description

Cover Preface to the Second Edition Contents 1. Transfer Processes 1.1 Introduction 1.2 Nature of Transfer Processes 1.3 Concept of Driving Potential 1.4 Physical Mechanisms 1.5 Heat Transfer in Fluids–Convection 1.6 Convective Mass Transfer 1.7 Radiant Energy Exchange 1.8 Descriptions of Some Heat and Mass Transfer Processes 1.8.1 Evaporative air cooler 1.8.2 Moisture Pick-up from Lakes 1.8.3 Spray Drying 1.8.4 Respiratory Gas Exchange in Lungs 1.8.5 Ablation of Meteorites Entering Atmosphere 1.8.6 Burning of Carbon in Air 1.9 Heat Transfer from Human Body 2. Conduction: Heat Transfer in Stationary Medium 2.1 Introduction 2.2 A Physical Law for Rate of Heat Transfer 2.3 Methodology 2.4 Basic Equation of Heat Conduction 2.5 Boundary and Initial Conditions 2.5.1 Specified-Temperature Condition 2.5.2 Specified-Flux Condition 2.5.3 Specified-Convection Condition 2.5.4 Condition at the Interface of Two Solids 2.6 Thermal Properties of Matter 2.6.1 Thermal Conductivity 2.6.2* Physical Basis of Conductivity 2.6.3 Thermal Diffusivity 2.7 Normalisation of the Heat Conduction Problem 2.7.1* Concept of Similarity 2.7.2* Basis of Approximations 3. Steady-State Conduction 3.1 Introduction 3.2 Steady-state Conduction in a Slab 3.2.1 Temperature Profile 3.2.2 Conduction with Convective Boundary Condition 3.2.3 Thermal Resistance of a Slab 3.2.4 Equivalent Resistance to Heat Loss by Radiations to the Surroundings 3.2.5 Significance of Biot Number 3.2.6 Contact Resistance 3.3 Heat Conduction Across a Cylindrical Shell 3.3.1 Temperature Profile and Heat Current 3.3.2 Thermal Resistance 3.3.3 The Critical Thickness of Cylinder Insulation 3.4 Steady Conduction in a Spherical Shell 3.4.1 Temperature Distribution 3.4.2 Lower Bound of Heat Transfer Coefficient h 3.5 Fins 3.5.1 Pin-Fins of Constant Cross-Section 3.5.2 Fin Performance: Fin Effectiveness and Fin Efficiency 3.5.3 Fins of Other Geometry 3.5.4 Heat Sinks for Electronic Components 3.5.5 Fins of Dinosaurs 3.6 Conduction with Uniformly Distributed Heat Sources 3.6.1 Conduction Across a Plane Wall with Distributed Heat Sources 3.6.2 Radial Conduction in a Cylindrical Rod with Distributed Heat Sources 3.7 Steady-state Conduction in Two-Dimensions 3.7.1 An Analogy with Ideal Fluid Flow 3.7.2 Conduction Shape Factors 4. Transient Conduction 4.1 Transient Conduction 4.2 Transient Conduction through an Infinite Slab 4.3 Transient Conduction in Long Cylinders 4.4 Transient Conduction in Sphere 4.5 Significance of Biot Number 4.6 Transient Heating of Bodies with Negligible Internal Resistance 4.7 Transient Conduction in Semi-Infinite Solid 4.7.1 Effect of Step Change in Temperature at the Boundary of a Semi-Infinite Solid 4.7.2 Concept of Penetration Depth 4.7.3 Significance of Thermal Diffusivity 4.7.4 Significance of Fourier Number 4.7.5 Food Cellar 4.7.6 Transient Conduction in Semi-infinite Slab with other Boundary Conditions 4.7.7 Contact of Two Infinite solids 4.8 Transient Conduction in Multi-dimensions 5. Numerical Methods forConduction Problems 5.1 Introduction 5.2 Some Elementary Ideas 5.2.1 The Nodal Mesh 5.2.2 Estimates of Derivatives 5.3 One- dimensional Conduction 5.3.1 Steady–State 1–D Conduction in a Slab 5.4 One- dimensional Fin 5.5 Two-dimensional Steady-state Conduction 5.5.1 An Interior Node 5.5.2 Node at a Plane Surface 5.6 Finite- Difference Formulation of 2-D Problems 5.7 Methods of Solution 5.8 Unsteady Heat Conduction in One-Dimension 5.8.1 Implicit and Explicit Schemes 5.9 Unsteady Conduction in Two-Dimensions 5.9.1 Energy Balance Equation for an Interior Cell 5.9.2 Node at a Plane Wall A5 Appendix: Matlab Programmes A5.1 Steady– state 1–D conduction in the slab of Sec. 5.3.1 A5.2 Example 5.1: 1–D conduction in a slab with convective boundary conditions A5.3 Example 5.2: Heat transfer across the walls of a thick cylindrical tube A5.4 Example 5.3: Electric blanket A5.5 One–dimensional fin A5.6 Example 5.4: Tapered fin A5.7 Gauss–elimination procedure A5.8 Gauss-Sidel procedure A5.9 Example 5.7 Unsteady conduction in a slab A5.10 Example 5.8: Semi-infinite solid 6. Convection– Empirical Approach 6.1 Introduction 6.2 Transpiration Cooling – The Basic Mechanism of Heat Convection 6.3 Convection from a Hot Body in a Fluid Stream 6.4 Non- Dimensional Parameters in Convection 6.4.1 Forced Convection 6.4.2 Significance of the Various Non-dimensional Parameters 6.5 Transport in Turbulent Flows 6.6 External Forced Convection 6.6.1 Concept of Boundary Layer 6.6.2 Estimating the Thickness of Velocity Boundary Layers 6.6.3 Thickness of Thermal Boundary Layers 6.6.4 Reynolds Analogy 6.6.5 Turbulent Boundary Layers 6.6.6 Separated Flows 6.6.7 Forced Convection from Cylinders 6.6.8 Forced Convection from a Sphere 6.6.9 Forced Convection across Banks of Tubes 6.6.10 Forced Convection in Packed Beds 6.7 Free or Natural Convection 6.7.1 Significance of Grashof Number 6.7.2 Vertical Walls 6.7.3 Free Convection from Horizontal and Inclined Walls 6.7.4 Free Convection from Horizontal Cylinders 6.7.5 Free Convection in Rectangular Enclosures 6.7.6 Quick Formulae for Free–Convection in Air 6.8 Forced Convection in Pipes and Ducts 6.8.1 Full– Development of Velocity Profile 6.8.2 Concept of Bulk Temperature 6.8.3* The Concept of Full–Development of Temperature Profiles 6.8.4 Nusselt Number for Fully–Developed Flows 6.8.5 Thermal Entry Length 6.9 Heat Transfer in Condensation 6.9.1 Correlations for Heat Transfer in Film Condensation 6.9.2 Laminar Film Condensation on Horizontal Pipes 6.10 Heat Transfer in Boiling 6.10.1 Physical Mechanisms 6.10.2 Variation of Boiling Heat Flux with Excess Temperature 6.10.3 Empirical Correlations 6.11 Summary of Some Useful Correlations for Heat Convection 7. Convection– Analytic Approach 7.1 Introduction 7.2 Transpiration Cooling – Illustrating the Basic Mechanism of Heat Convection 7.3 Basic Approach in Analysing a Convection Problem 7.4 Concept of Full-development Revisited 7.5 Heat Transfer in Couette Flow 7.5.1 Velocity Profile 7.5.2 Temperature Profile 7.5.3 Recovery Temperature 7.6 Flow Through a Circular Tube 7.6.1 Fully– Developed Velocity Profile 7.6.2 Constant Wall–Flux Case – Axial Gradient of Temperature 7.6.3 Constant Wall–Flux Case—Temperature Profile 7.6.4 Constant Wall Temperature Case—Log Mean Temperature Difference 7.7 Heat Transfer in External Convection 7.7.1 Thermal Boundary Layer for Pr