Basic Heat Transfer (eBook)

Front Cover 1
Basic Heat Transfer 4
Copyright Page 5
Table of Contents 8
Preface 6
Acknowledgement 7
Preface 6
Chapter 1. Introduction to BASIC 12
1.1 The BASIC approach 12
1.2 The elements of BASIC 12
1.3 Checking programs 18
1.4 Summary of BASIC statements 18
References 19
WORKED EXAMPLES 19
1.1 Useful mathematical routines 19
Chapter 2. Simple heat transfer 23
2.1 Introduction 23
2.2 Conduction 23
2.3 Thermal conductivity 23
2.4 One-dimensional conduction 24
2.5 Convection 25
2.6 Electrical analogy 26
2.7 Overall heat transfer coefficient 26
2.8 Radiation 28
2.9 Laws of black body radiation 28
2.10 Emissivity and grey body radiation 29
2.11 Heat transfer for a grey body in black surroundings 29
2.12 Radiation heat transfer coefficient 30
2.13 Simple transient problems in heat transfer 30
References 31
WORKED EXAMPLES 31
2.1 Heat transfer in a plane wall 31
2.2 Room heater 34
2.3 Building heat losses and heaters 35
2.4 Economic insulation of a pipe 37
2.5 Lumped capacity system with a grey body in large surroundings 40
PROBLEMS 42
Chapter 3. Conduction 45
3.1 Introduction 45
3.2 General conduction equation 45
3.3 Finite difference formulation 46
3.4 Steady state two-dimensional conduction 47
3.5 Boundary conditions 48
3.6 Heat transfer rates at a boundary 49
3.7 One-dimensional transient conduction 50
3.8 Boundary conditions 52
3.9 Significance of the Fourier number, F 52
3.10 Heat transfer 52
3.11 Transient heat transfer charts 53
References 54
WORKED EXAMPLES 54
3.1 Two-dimensional steady state conduction 54
3.2 One-dimensional transient conduction, explicit method 59
3.3 One-dimensional transient conduction, implicit method 63
3.4 One-dimensional transient conduction with convective boundary 69
3.5 Two-dimensional transient conduction, explicit method 72
PROBLEMS 76
Chapter 4. Convection 81
4.1 Introduction 81
4.2 Boundary layers 82
4.3 Boundary layer analysis 82
4.4 Determination of laminar and turbulent flow 83
4.5 Reynolds' analogy 84
4.6 Dimensional analysis in convection 86
4.7 Free convection 86
4.8 Phase change 87
4.9 Complex surfaces 87
4.10 Use of empirical relations 88
References 88
WORKED EXAMPLES 88
4.1 Water and air properties 88
4.2 Experimental Nu–Re relation 90
4.3 Surface heat transfer coefficient in smooth tubes 94
4.4 Free convection at vertical surfaces 98
4.5 Laminar film condensation 101
PROBLEMS 105
Chapter 5. Radiation 112
5.1 Introduction 112
5.2 Intensity of radiation 112
5.3 The geometric factor 113
5.4 Grey body radiation 115
5.5 Electrical analogy for radiation 115
5.6 General multisurface grey body radiation 117
5.7 Non-grey bodies 118
5.8 Special situation 118
5.9 Gas radiation 119
References 119
WORKED EXAMPLES 119
5.1 Intensity of radiation 119
5.2 Geometric factor 122
5.3 Radiation heat transfer between two grey surfaces 124
5.4 General grey body program 125
PROBLEMS 128
Chapter 6. Finned surfaces 134
6.1 Introduction 134
6.2 Strip fins of rectangular profile 134
6.3 Annular fins and tap ered fins 136
6.4 Arrays of fins 137
6.5 U se of fins 138
References 138
WORKED EXAMPLES 138
6.1 Heat transfer in a strip fin of rectangular profile 138
6.2 An array of fins of the type used in Program 6.1 142
6.3 Circumferential fin 144
PROBLEMS 149
Chapter 7. Heat exchangers 153
7.1 Introduction 153
7.2 The LMTD method 153
7.3 The NTU method 156
7.4 Complex or extended surface heat exchangers 157
7.5 Pressure loss in heat exchangers 158
7.6 Efficiency of heat exchangers 158
7.7 Fouling in heat exchangers 159
References 159
WORKED EXAMPLES 159
7.1 Heat exchanger design considerations 159
7.2 Shell and tube heat exchanger–LMTD method 164
7.3 Cross-flow heat exchanger–NTU method 167
7.4 Car radiator design 171
PROBLEMS 175
Index 182