Preface Chapter 1. Introduction to Heat Transfer During the Forming of Organic Matrix Composites

Transcription

1 Preface... xv Chapter 1. Introduction to Heat Transfer During the Forming of Organic Matrix Composites... 1 Didier DELAUNAY 1.1. Introduction Examples of injection of short fiber reinforced composites Heat transfer during the filling phase Heat transfer during part consolidation Injection on continuous fiber reinforcements Conclusion: toward a controlled processing Bibliography Chapter 2. Experimental Determination and Modeling of Thermophysical Properties Nicolas BOYARD and Didier DELAUNAY 2.1. Measurement of specific volume and shrinkage Thermoplastic PvT diagram Specific volume of thermosetting polymers Determination of specific heat capacity of resin and composites Thermal conductivity: a tricky task A first assessment of experimental data Overview of the main characterization techniques to measure the thermal conductivity of polymers and associated composites Modeling of the thermal conductivity of composites... 57

2 vi Heat Transfer in Polymer Composite Materials 2.4. Conclusions Bibliography Chapter 3. Experimental Determination and Modeling of Transformation Kinetics Nicolas BOYARD, Jean-Luc BAILLEUL and M hamed BOUTAOUS 3.1. Introduction What are the most suitable devices to analyze a reaction rate? Conventional methods Original methods A first assessment of the current characterization methods Modeling of the cure kinetics of thermosetting resins Mechanistic models: complexity versus accuracy Description of the kinetics with empirical models: the engineer approach Modeling of the diffusion induced by vitrification Overall crystallization kinetics of semi-crystalline thermoplastics Most popular crystallization kinetics models for process simulations Systems of differential equations Measurements of crystallization kinetics and associated parameters Models for specific crystallization phenomena and geometries Concluding remarks Bibliography Chapter 4. Phase Change Kinetics within Process Conditions and Coupling with Heat Transfer M hamed BOUTAOUS, Matthieu ZINET, Nicolas BOYARD and Jean-Luc BAILLEUL 4.1. Introduction Flow-induced crystallization: experimental observations Relevant experimental techniques Effect of flow on crystallization kinetics Flow effect on crystalline morphology Flow effect on crystalline growth rate

3 vii Effect of flow on rheological properties Summary of experimental observations and guidelines for modeling Flow-induced crystallization: modeling Overall kinetics modeling Explicit nucleation and growth modeling Role of viscoelasticity Effect of the composite components Effect of nucleating agents Effect of fibers Concluding remarks Bibliography Chapter 5. From the Characterization and Modeling of Cure-Dependent Properties of Composite Materials to the Simulation of Residual Stresses Yasir NAWAB and Frédéric JACQUEMIN 5.1. Introduction Origin of residual stress Mechanical levels of residual stress Parameters contributing to the formation of residual stress Problems generated by residual stress Determination of composite properties Modeling the mechanical properties of composites Experimental determination of thermomechanical properties of composite Modeling of residual stress Linear approach or classical theory of laminates Nonlinear approach Minimization of energy approach Application Conclusion Bibliography Chapter 6. Heat Transfer in Composite Materials and Porous Media: Multiple-Scale Aspects and Effective Properties Michel QUINTARD 6.1. Introduction Effective thermal conductivity Background on upscaling methods

4 viii Heat Transfer in Polymer Composite Materials A simple example: continuous thermal conductivity Effective thermal conductivity: properties and bounds Local-equilibrium model and thermal dispersion Local equilibrium versus local non-equilibrium models The two-equation model Further discussion Various extensions Effect of homogeneous and heterogeneous thermal sources Interfacial thermal resistance Conclusions Bibliography Chapter 7. Thermal Optimization of Forming Processes Vincent SOBOTKA 7.1. Context of optimization Heat transfer: optimization lever Definition of the optimization criterion Problem modeling Spatial scale Time scale: process steps Multi-physical aspects Numerical optimization methods The adjoint problem Practical setting of the method Example of process optimization: determination of optimal heat flux setpoint Experimental setup and constraint Instrumentation of the mold and the preform Thermal modeling Experimental data from a composite part molding Estimation of the thermal contact resistances Determination of the optimal setpoint Optimal design of molds OSOTO project The considered thermoplastic part General methodology Conformal cooling approach

5 ix Heat transfer model in the process Objective function Minimization of the functional J Cooling channel design Conclusions and outlook Bibliography Chapter 8. Modeling of Thermoplastic Welding Gilles REGNIER and Steven LE CORRE 8.1. Introduction Polymer welding processes Healing mechanisms of polymer interfaces Physics of thermoplastic welding Intimate contact at interface Macromolecular diffusion Linear viscoelasticity to quantify the macromolecular diffusion Application to continuous welding of composite tape Process description Influence of processing conditions on interfacial strength Modeling of macromolecular diffusion Modeling of thermal aging Thermal modeling of the process Weldability prediction Application to ultrasonic welding Process description and time scale separation Process modeling: necessity of a time homogenization framework Numerical multi-physical model Ultrasonic welding with energy directors: process analysis and optimization Conclusion Acknowledgments Bibliography Chapter 9. Multiphysics for Simulation of Forming Processes Luisa SILVA, Patrice LAURE, Thierry COUPEZ and Hugues DIGONNET 9.1. Introduction Multiscale, multiphysics and multidomain modeling Flow equations

6 x Heat Transfer in Polymer Composite Materials Thermal-rheological-kinetical coupling Orientation and structure development during processing Advanced numerical techniques and macroscale simulations Implicit boundaries Immersed subdomains and regularization Multiphase flow and thermokinetical numerical resolution Composite forming simulation illustrations Parallel mesh adaptation and highperformance computing Determination of equivalent properties and microscale simulations Generation of representative numerical samples Permeability of a composite Stiffness tensor determination Conclusions Bibliography Chapter 10. Thermal Instrumentation for the Control of Manufacturing Processes of Organic Matrix Composite Materials Jean-Christophe BATSALE and Christophe PRADERE Introduction Methods based on contact measurement Temperature sensors and fluxmeters Heat flux estimation Thermal probes for thermophysical property measurement in static conditions Contactless heating Photothermal methods with monosensors (under microscale characterization) Thermal non-destructive evaluation: cracks or delamination detection in composite samples Screening of chemical processes and microfluidic experiments Principles for the factory global monitoring, example of conveyor belt parameter estimation In a near future: the Big Data related to multiscale process survey

7 xi Conclusion Bibliography Chapter 11. Sensors for Heat Flux Measurement Fabien CARA and Vincent SOBOTKA Motivations: heat flux sensor Principle of heat flux sensors Gradient heat flux sensor Inertial heat flux sensor Inverse heat flux sensor Main characteristics of HFS Invasiveness Time constant Calibration Type, positioning and use of heat flux sensors Commercial sensors Positioning of heat flux sensors Price Advantages and limitations of HFS compared to other in situ monitoring techniques Advantages Limitation and care in using HFS Examples Compression molding Resin transfer molding flow front detection Resin transfer molding: influence of mold temperature Internal temperature prediction during infusion Glass mat transfer, internal temperature monitoring Conclusions HFS suppliers Bibliography Chapter 12. Thermal Radiative Properties of Polymers and Associated Composites Benoit ROUSSEAU Introduction Fundamental requisites concerning thermal radiation Spectral range of thermal radiation

8 xii Heat Transfer in Polymer Composite Materials Radiant energy, radiant flux, radiative flux density and radiative intensity Blackbody spectral emissive power Radiative properties at interfaces Radiative properties of semi-transparent slabs Prediction of the radiative properties of homogeneous semi-transparent slabs: case of the isotactic polypropylene Intrinsic optical properties for a homogeneous, isotropic and non-magnetic medium Prediction of the radiative properties of polypropylene slabs at 20 C Radiative properties of polymer composites with fiber structures Normal spectral absorptance of Roving TWINTEX Normal spectral absorptance of sheet of PEEK with carbon fibers Conclusion Bibliography Chapter 13. Infrared Radiation Applied to Polymer Processes Yannick LE MAOULT and Fabrice SCHMIDT Introduction Why use infrared heating for polymers? Application of radiative transfers in polymer processing Infrared radiation characteristics Radiative properties (basis and main definitions) Infrared emitters: characterization Infrared camera measurements Modeling of infrared radiation Opaque medium: surface to surface methods Semi-transparent medium Ray tracing method Polymer processing applications Optimization of preform temperature for the ISBM process Optimal infrared composite curing Future work

9 xiii Acknowledgements Bibliography List of Authors Index