HEAT TRANSFER THERMAL MANAGEMENT OF ELECTRONICS YOUNES SHABANY. C\ CRC Press W / Taylor Si Francis Group Boca Raton London New York

Transcription

1 HEAT TRANSFER THERMAL MANAGEMENT OF ELECTRONICS YOUNES SHABANY C\ CRC Press W / Taylor Si Francis Group Boca Raton London New York CRC Press is an imprint of the Taylor & Francis Group, an informa business

2 Contents Preface About the Author xiii xv Chapter 1 Introduction Semiconductor Technology Trends Temperature-Dependent Failures Temperature-Dependent Mechanical Failures Temperature-Dependent Corrosion Failures Temperature-Dependent Electrical Failures Importance of Heat Transfer in Electronics Thermal Design Process 14 References 18 Chapter 2 Energy, Energy Transfer, and Heat Transfer Energy and Work Macroscopic and Microscopic Energies Energy Transfer and Heat Transfer Equation of State 25 Problems 28 References 28 Chapter 3 Principle of Conservation of Energy First Law of Thermodynamics Energy Balance for a Control Mass Energy Balance for a Control Volume 36 Problems 44 References 51 Chapter 4 Heat Transfer Mechanisms Conduction Heat Transfer Convection Heat Transfer Simplified Correlations for Convection Heat Transfer in Air Radiation Heat Transfer 61 Problems 64 References 65 vii

3 viii Contents Chapter 5 Thermal Resistance Network Thermal Resistance Concept Series Thermal Layers Parallel Thermal Layers General Resistance Network Thermal Contact Resistance Thermal Interface Materials Spreading Thermal Resistance Thermal Resistance of Printed Circuit Boards (PCBs) 91 Problems 97 References 101 Chapter 6 Thermal Specification of Microelectronic Packages Importance of Packaging Packaging Types Thermal Specifications of Microelectronic Packages Junction-to-Air Thermal Resistance Junction-to-Case and Junction-to-Board Thermal Resistances Package Thermal Characterization Parameters Package Thermal Resistance Network Parameters Affecting Thermal Characteristics of a Package Package Size Packaging Material Die Size Device Power Dissipation Air Velocity Board Size and Thermal Conductivity 122 Problems 123 References 125 Chapter 7 Fins and Heat Sinks Fin Equation Infinitely Long Fin Adiabatic Fin Tip Convection and Radiation from Fin Tip Constant Temperature Fin Tip Fin Thermal Resistance, Effectiveness, and Efficiency Fins with Variable Cross Sections Heat Sink Thermal Resistance, Effectiveness, and Efficiency Heat Sink Manufacturing Processes 160

4 Contents ix Problems 164 References 168 Chapter 8 Heat Conduction Equation One-Dimensional Heat Conduction Equation for a Plane Wall General Heat Conduction Equation Boundary and Initial Conditions Temperature Boundary Condition Heat Flux Boundary Condition Convection Boundary Condition Radiation Boundary Condition General Boundary Condition Interface Boundary Condition Steady-State Heat Conduction One-Dimensional, Steady-State Heat Conduction Two-Dimensional, Steady-State Heat Conduction Transient Heat Conduction Lumped Systems Simple Lumped System Analysis General Lumped System Analysis Validity of Lumped System Analysis 202 Problems 204 References 208 Chapter 9 Fundamentals of Convection Heat Transfer Type of Flows External and Internal Flows Forced and Natural Convection Flows Laminar and Turbulent Flows Steady-State and Transient Flows Viscous Force, Velocity Boundary Layer, and Friction Coefficient Temperature Boundary Layer and Convection Heat Transfer Coefficient Conservation Equations Boundary Layer Equations 217 References 218 Chapter 10 Forced Convection Heat Transfer: External Flows Normalized Boundary Layer Equations Reynolds Number, Prandtl Number, Eckert Number, and Nusselt Number 221

5 x Contents 10.3 Functional Forms of Friction Coefficient and Convection Heat Transfer Coefficient Flow over Flat Plates Laminar Flow over a Flat Plate with Constant Temperature Turbulent Flow over a Flat Plate with Uniform Temperature Flow over a Flat Plate with Uniform Surface Heat Flux Flow Across Cylinders Cylindrical Pin-Fin Heat Sink Procedure for Solving External Forced Convection Problems 246 Problems 248 References 253 Chapter 11 Forced Convection Heat Transfer: Internal Flows Mean Velocity and Mean Temperature Laminar and Turbulent Pipe Flows Entry Length and Fully Developed Flow Pumping Power and Convection Heat Transfer in Internal Flows Velocity Profiles and Friction Factor Correlations Temperature Profiles and Convection Heat Transfer Correlations Fans and Pumps Types of Fans Fan Curve and System Impedance Curve Fan Selection Types of Pumps Plate-Fin Heat Sinks 281 Problems 283 References 285 Chapter 12 Natural Convection Heat Transfer Buoyancy Force and Natural Convection Flows Natural Convection Velocity and Temperature Boundary Layers Normalized Natural Convection Boundary Layer Equations Grashof and Rayleigh Numbers Functional Form of the Convection Heat Transfer Coefficient 295

6 Contents XI 12.4 Laminar and Turbulent Natural Convection over a Vertical Flat Plate Natural Convection around Inclined and Horizontal Plates Natural Convection around Vertical and Horizontal Cylinders Natural Convection in Enclosures Natural Convection from Array of Vertical Plates Mixed Convection 313 Problems 314 References 318 Chapter 13 Radiation Heat Transfer Radiation Intensity and Emissive Power Blackbody Radiation Radiation Properties of Surfaces Surface Emissivity Surface Absorptivity Surface Reflectivity Surface Transmissivity Kirchhoff's Law Solar and Atmospheric Radiations Radiosity View Factors Radiation Heat Transfer between Black Bodies Radiation Heat Transfer between Nonblack Bodies Radiation Heat Transfer from a Plate-Fin Heat Sinks 343 Problems 349 References 350 Chapter 14 Computer Simulations and Thermal Design Heat Transfer and Fluid Flow Equations: A Summary Fundamentals of Computer Simulation Steady-State, One-Dimensional Heat Conduction Steady-State, Two-Dimensional Heat Conduction Transient Heat Conduction Fluid Flow and Energy Equations Turbulent Flows Solution of Finite-Difference Equations Commercial Thermal Simulation Tools Creating the Thermal Model 382

7 xii Contents Creating the Mesh Solving Flow and Temperature Equations Review the Results Presenting the Results Importance of Modeling and Simulation in Thermal Design 398 References 399 Chapter 15 Experimental Techniques and Thermal Design Flow Rate Measurement Techniques System Impedance Measurement Fan and Pump Curve Measurements Velocity Measurement Methods Temperature Measurement Techniques Acoustic Noise Measurements Importance of Experimental Measurements in Thermal Design 419 References 420 Chapter 16 Advanced Cooling Technologies Heat Pipes Capillary Limit Boiling Limit Sonic Limit Entrainment Limit Other Heat Pipe Performance Limits Heat Pipe Applications in Electronic Cooling Heat Pipe Selection and Modeling Thermosyphons, Loop Heat Pipes, and Vapor Chambers Liquid Cooling Thermoelectric Coolers Electrohydrodynamic Flow Synthetic Jet 450 References 452 Appendix: Tables of Material Properties 455 Index 471