Modeling the resin flow and numerical simulation of the filling stage for vacuum-assisted resin infusion process

Abstract

The preform is covered by a flexible vacuum bag in vacuum-assisted resin infusion process, and the preform compaction state is time and space dependent during the mould-filling stage, there is no practical tool for the filling simulation. In this paper, the resin flow governing equations for vacuum-assisted resin infusion are built based on the analysis of the preform compaction behaviour and the fibre tow impregnation. For obtaining the numerical solution conveniently and accurately, an alternative approach is proposed in which the primary flow is computed from the normal Darcy's law, two-slave elements are added to each master element, named sink slave element and deformation slave element, to calculate the resin mass variation caused by fibre tow infiltration and preform deformation. Three examples are conducted to verify the precision and broad applicability of the approach. The influence of the preform deformation and the unsaturated effect on the mould filling is analysed.

Experimental and Numerical Study of Vacuum Resin Infusion for Thin-Walled Composite Parts

“…Due to the above-mentioned improvements while ensuring a low degree of the resin cure at the end of the preform filling [13,[15][16][17][18][19][20][21] they were successfully implemented in the manufacture of aircraft structures (usually shell type) [1,22,23], blades of the wind turbines [1,20,[24][25][26][27], ship's hulls [1,2,20,24,25], details of spacecraft [1,28], large-sized parts of cars bodies [29,30] and in the defense industry [7,27].…”

Experimental and Numerical Study of Vacuum Resin Infusion for Thin Walled Composite Parts

“…A process of vacuum assisted composite fabrication is widely used for producing large components with good quality, and widely applying in aircraft [1][2][3], shipbuilding [1, 4 -7], automotive [8], wind energy [4,7,9,10] and defense industries [5,10], due to its low cost, timeconsuming, simplicity of the required equipment and better ecology conditions at the manufacturing.…”

“…Historically, the first such system was the LIMS software [11,16,19,35], the theoretical foundations of which were presented in the 90s of the 20th century and presented in [36]. Late the kind of the similar systems has been developed and used by some scientists: PAM-RTM [16,20,22,37]; RTM-WORKS [4,6,9]; 3DINFIL [38]; RTMSim [39]; Moldex3D RTM [40] and the ANSYS Fluent module [3,7]. All of these systems are based on the use of the so-called Finite Element / Control Volume (FE / CV) method, which uses special means of monitoring the front movement of the resin to eliminate the need to work with the moving boundaries and the deformed finite element mesh.…”

“…The modeled parts were assumed to be non-planar, such as shell-like, the thickness of which is much smaller than other dimensions of the part. This approach was implemented in almost all later works [7,10,17,37], including the most recent ones [20]. The construction of the resin flow theory in these works always begins with Darcy's law:…”

“…Tracking the interface between the air and the resin is performed by solving the continuity equation for the volume fraction of resin Vr [7,10,17,20,36,37]:…”