Simulation numerique du procede de deposition chimique en phase vapeur assistee par laser (LCVD) de fibres de carbone

Laser Chemical Vapor Deposition (LCVD) is a promising but complex process especially when depositing microscopic three-dimensional structures. These structures can be used in microelectronics (for example as micro-antennae) or as reinforcements in high-performance composites. To become a commercial competitor for fibers manufacturing, three-dimensional LCVD must have an optimal control process. Computer fluid dynamics (CFD) is an ideal tool to reach that goal because it allows the analysis of the main phenomena of the LCVD process which are interdependent.; Starting with a global numerical simulation, this study shows a direct correlation between the way precursor gases are brought to the deposition zone and the precision and rate of deposition. Precursor gas injection is modeled as an annular flow moving along the fiber's surface.; Following with a specific numerical simulation whose control volume is more precisely delimited around the fiber's tip, the study tries to analyze the effects of the ejection of reaction products on the deposition process.; The study concludes with a discussion on choosing an adequate analysis tool since three-dimensional LCVD includes micro-fluidic processes which are not commonly implemented in mainstream CFD software. (Abstract shortened by UMI.)...