[en] The manufacturing process of glass fibers used for the reinforcement of composite material consists in drawing a glass melt at high temperature through an array of thousands of small orifices (i.e. the bushing plate) into fibers using a winder. This process is sensitive to numerous disturbances that can cause the fiber to break during the drawing process. In order to understand the origin of these failures and improve the process efficiency, it is important to understand the physics of the forming fiber. Unlike other glass forming processes, this process is characterized by a high cooling rate. As a consequence, the heat transfers have a strong influence on the fiber forming behavior. We study here the heat transfer mechanisms through numerical simulations of one single fiber. Several key parameters are presented through sensitive analysis (e.g. influence of the material emissivity, surrounding environment, process parameters). These studies are linked to measurements obtained from a dedicated experimental unit. In addition, the impact of the temperature variations at the bushing plate is investigated. Finally, we show how the forming stress is influenced by these parameters. It is found that convection by air entrainment around the fiber and thus the environment conditions represent a critical contribution to the cooling rate. On the other hand, results also demonstrate that the heat pattern of the bushing plate is one of the most important causes for disturbance in the process.
