A numerical investigation of the resin flow front tracking applied to the RTM process

Abstract

Resin Transfer Molding (RTM) is largely used for the manufacturing of high-quality composite components and the key stage during processing is the resin infiltration. The complete understanding of this phenomenon is of utmost importance for efficient mold construction and the fast production of high quality components. This paper investigates the resin flow phenomenon within the mold. A computational application was developed to track the resin flow-front position, which uses a finite volume method to determine the pressure field and a FAN (Flow Analysis Network) technique to track the flow front. The mass conservation problem observed with traditional FE-CV (Finite Element-Control Volume) methods is also investigated and the use of a finite volume method to minimize this inconsistency is proposed. Three proposed case studies are used to validate the methodology by direct comparison with analytical and a commercial software solutions. The results show that the proposed methodology is highly efficient to determine the resin flow front, showing an improvement regarding mass conservation across volumes.

Flow front advancement during composite processing: predictions from numerical filling simulation tools in comparison with real-world experiments

“…In this approach, the dry preform is considered as a porous medium, which is solely characterized by its permeability (see for example Refs. ).…”

Modeling and simulation of filling in dual-scale fibrous reinforcements: state of the art and new methodology to quantify the sink effect

“…29 The pressure is calculated in the nodes of the FEM mesh and then, the pressure gradients can be approximated using a finite difference scheme and the velocity is calculated by Darcy law. For partially filled CVs, the position of the fluid front is determined by interface capturing schemes, with the flow analysis network (FAN) scheme, originally proposed by Tadmor et al 30 and subsequently implemented in the filling of fibrous reinforcements, 4,[31][32][33] as one of the most used. The FEM/CV conforming scheme is the base of the commercial software LIMS.…”

“…where the coefficients m are obtained from the inverse of the matrix [F], which in turns is obtained by collocation of N B boundary nodes and N I internal nodes according to equation (33); in other words, equation (33) can be written in vector form ask ¼ F ½ , from which ¼ F ½ À1k . The boundary and the physical variables in this problem are discretized using quadratic isoparametric interpolation.…”

“…The radial injection is carried out and several captures are done; using the pictures taken and image processing software, the fluid-front positions at several times are obtained. In the present simulation, the mesh size used in the work of Vanegas et al 17 is also considered and, additionally, interior points are positioned in the domain to make the interpolation of the non-homogeneous term, kx À Á , more robust, see equation (33). From now on, the simulation performed by Vanegas et al 17 is referred to as the BEM simulation, whereas the one run in this work as the DR-BEM simulation.…”

Computational modeling of resin infusion process applied to small vessel hulls

“…It is important to highlight that there are many works in the literature about numerical simulation of LCM processes [6], most of than related to the resin transfer molding (RTM) process [14][15][16][17]; however, great majority of them do not consider the empty injection channels. The most common approach used to simulate the RTM process is known in the literature as finite element-control volume (FE-CV) method ( [18][19][20][21]). This method combines the Darcy's equation (for a porous medium) with the continuity equation, resulting in a equation for pressure.…”