Heat transfer between two bodies in thermal contact is of fundamental importance in a wide variety of applications ranging from industrial and domestic processes to fundamental biology and chemistry. This book covers both the theoretical and practical aspects of thermal contact conductance. The theoretical discussion covers heat transfer through spots, joints, and surfaces, as well as the role of interstitial materials (both planned and inadvertent). The practical discussion includes formulae and data for use in designing heat-transfer equipment for a variety of joints, including special geometries and configurations.

Inhalt

1 Introduction.- 1.1 Mechanism of Contact Heat Transfer.- 1.2 Significance of Contact Heat Transfer.- 1.3 Scope of Present Work.- References.- 2 Thermal Constriction Resistance.- 2.1 Circular Disc in Half Space.- 2.2 Resistance of a Constriction Bounded by a Semi-Infinite Cylinder.- 2.3 Constriction in a Fluid Environment.- 2.4 Other Types of Constrictions.- References.- 3 Solid Spot Thermal Conductance of a Joint.- 3.1 Multiple Spot Contact Conductance.- 3.2 Estimation of the Number and Average Size of Contact Spots.- 3.2.1 Gaussian Distribution of Heights and Slopes.- 3.3 Deformation Analysis.- 3.3.1 The Plasticity Index.- 3.3.2 Ratio of Real to Apparent Area of Contact.- 3.4 Theoretical Expressions for Thermal Contact Conductance.- 3.4.1 Solid Spot Conductance for Fully Plastic Deformation.- 3.4.2 Solid Spot Conductance for Elastic Deformation.- 3.5 Effect of Macroscopic Irregularities.- 3.6 Correlations for Solid Spot Conductance.- 3.7 Numerical Example: Solid Spot Conductance.- References.- 4 Gas Gap Conductance.- 4.1 Factors Affecting Gas Gap Conductance.- 4.2 The Accommodation Coefficient.- 4.2.1 Effect of Temperature on Accommodation Coefficient.- 4.2.2 Summary of Observations.- 4.3 Effect of Gas Pressure on Gas Gap Conductance.- 4.4 Correlations for Gas Gap Conductance.- 4.5 Gas Gap Conductance: Conclusions.- 4.6 Numerical Example: Gas Gap Conductance.- References.- 5 Experimental Aspects.- 5.1 Axial Heat Flow Apparatus.- 5.2 Radial Heat Flow Apparatus.- 5.3 Periodic Contacts.- 5.4 Transient Measurements.- 5.5 Analog Methods.- 5.6 Accuracy.- 5.7 Summary.- References.- 6 Control of Thermal Contact Conductance Using Interstitial Materials.- 6.1 Solid Interstitial Materials.- 6.2 Metallic Foils.- 6.3 Wire Screens.- 6.4 Surface Coatings.- 6.4.1 Constriction Resistance in a Plated Contact.- 6.4.2 Thermal Contact Conductance of Coated Surfaces.- 6.5 Insulating Interstitial Materials.- 6.6 Lubricating Films and Greases.- 6.7 Other Interstitial Materials.- References.- 7 Special Topics in Thermal Contact Conductance.- 7.1 Bolted or Riveted Joints.- 7.1.1 Stress Distribution at the Bolted Joint Interface.- 7.1.2 Heat Transfer in Bolted Joints.- 7.1.3 Summary.- 7.2 Cylindrical Joints.- 7.3 Rectification.- 7.3.1 Rectification at Moderate to High Contact Pressures.- 7.3.2 Specimens with Spherical Caps.- 7.3.3 Plane Ended Specimens.- 7.3.4 Microscopic Resistance.- 7.3.5 Rectification at Low Contact Pressures.- 7.3.6 Summary.- 7.4 Hysteresis.- 7.5 Effective Thermal Conductivity of Packed Beds.- 7.6 Stacks of Laminations.- 7.7 Solid Spot Conductance of Specific Materials.- 7.7.1 Stainless Steel and Aluminum.- 7.7.2 Zircaloy-2/Uranium Dioxide Interfaces.- 7.7.3 Porous Materials.- 7.8 Thermal Contact Resistance in the Presence of Oxide Films.- References.- 8 Concluding Remarks.- 8.1 Control of Thermal Contact Conductance.- 8.1.1 Bare Metallic Junctions.- 8.1.2 Use of Interstitial Materials.- 8.1.3 Load Cycling.- 8.1.4 Heat Flow Direction.- 8.1.5 Stacks of Laminations.- 8.2 Recommendations for Further Research.- References.- Author Index.