| Extended program |
Introduction to the different hyperthermal environments: the atmospheric reentry flight and classification based on heat fluxes, generalities on chemical propulsion, liquid engines and solid or hybrid rocket motors, specific and total impulse, the de Laval nozzle, structural materials the motor case, thrust vectoring; - Introduction to high temperature materials or Thermal Protection System (TPS); - Non-ablative TPS materials for atmospheric reentry: generalities on non- ablative TPS materials, low density ceramic materials, manufacturing processes, diffusion and sintering, Reusable Surface Insulation, the Space Shuttle heat shield; - Ablative TPS materials: refractory metals, ceramics, carbon materials, graphite, mechanisms of erosion and thermo-oxidation, introduction to polymeric ablative TPS materials, application examples in rocket propulsion; - Insulating materials: elastomeric matrix (EPDM and silicone), production methods (calendering, kneader, etc.), examples of EPDM/Kevlar formulations, SLA-561V, DC 93-104; vulcanization, peroxides, specific applications, rigid matrix insulating materials, production methods, wood, cork (P50); - Fiber-reinforced TPS materials: matrix classification, thermal and dimensional stability, phenolic matrices, cure cycles, carbon yield, generalities on fibers (glass, basalt, silica, carbon), surface treatment, fillers, thermal and mechanical properties of fiber-reinforced TPS materials; - Nanostructured TPS materials: introduction, differences between low and high heat flux ablation mechanisms; - Carbon/phenolic type fiber-reinforced TPS materials: fiber fabrication process (Rayon, PAN and pitch), differences between fiber types in terms of chemical functionalization and affinity to different polymer matrices, thermal and mechanical properties, production techniques of carbon/phenolic composites, applications, hints on sizing a carbon/phenolic laminate (new review); - Basic thermophysical characterization of TPS materials: thermodynamics, definition of heat capacity, thermal conductivity, temperature measurement theory, Seebeck effect, types of thermocouples, data acquisition systems, thermal characterization techniques (TGA/DTG/DTA, DSC, LFA), dimensional stability, characterization techniques (TMA), role of heating rate; - Advanced thermophysical characterization; - Advanced characterization of TPS materials: thermal conditions, chemical conditions, mechanical conditions, types of torches (plasma,arc-jet, HVOF, etc.), oxy-acetylene torch, determination of heat flux, calibration, types of calorimeters (slug, Gardon gages, etc.), role of oxidizer/fuel ratio, test examples, morphological characterization of flame-exposed surface, definition of mass loss and erosion rate, post-test and real time erosion rate measurement systems; - Advanced characterization of TPS materials using liquid propellant engine-based test beds, solid propellant engine-based test beds, NASA MSFC test system, hybrid engine-based test beds, X-ray analysis of TPS materials. - Ultra lightweight TPS materials: Lightweight Ceramic Ablators, Phenolic Impregnated Carbon Ablators, manufacturing methods; - Introduction to modeling ablative phenomena: introduction to mathematics governing the degradation of materials, degradation kinetics (Friedman's methods, Ozawa, etc.), Arrhenius' law determination of kinetic parameters by TGA, rule of mixtures, modeling of the thermal conductivity and heat capacity also as a function of temperature, mechanical erosion, differences between surface and volume ablation. |
