THEORETICAL AND EXPERIMENTAL MODELLING OF BUBBLE FORMATION WITH CONNECTED CAPILLARIES IN LIQUID COMPOSITE MOULDING PROCESSES

Yanneck Wielhorski (1) , Mohamed Amine Ben Abdelwahed (1) , Laurent Bizet (1) , Joël Bréard (1)

1 LOMC - Laboratoire Ondes et Milieux Complexes

The void prediction in LCM processes sparks off interest within the composite material industry because it is a significant issue to keep the expected mechanical properties. The liquid properties, the preform geometry and the flow conditions impact the quantity of void entrapped inside the final product. The complex geometry of the reinforcement due to the arrangement of the bundles and the fibres is a key point to understand and quantify this phenomenon. This paper deals with both simple model networks which can occur inside a fabric representing connected capillaries, so-called "Pore Doublet Model (PDM)". A first is considering two capillaries converging on a node (T-junction) and a second is representing two capillaries interconnected with a supplying principle. These configurations can affect locally the evolution of flow fronts. First, experiments of bubble formed in a T-junction device have been performed and studied. Then a theoretical approach was proposed to forecast microvoid and macrovoid formation, by taking into account a supplying principle and arranged Washburn equation in forced filling.

Mots clés: LCM; Void; Imbibition; Pore Doublet Model; Supplying principle; Filling

Domaines: Matériaux; Génie des procédés; Mécanique des fluides [physics.class-ph]; Mécanique des fluides [physics.class-ph]

Yanneck Wielhorski, Mohamed Amine Ben Abdelwahed, Laurent Bizet, Joël Bréard. THEORETICAL AND EXPERIMENTAL MODELLING OF BUBBLE FORMATION WITH CONNECTED CAPILLARIES IN LIQUID COMPOSITE MOULDING PROCESSES. 11th International Conference Flow Processing in Composite Materials, Jul 2012, Auckland, New Zealand. ⟨hal-00718687⟩