In the course of this study, the simulation of the resin flow in the RTM process is developed by the control volume finite element method (CVFEM) coupled with the equation of the free surface location. This location is made by means of the so called "Volume of Fluid" methods or VOF. Thus, the position of the flow front, the time-lapse and the rate of the non saturated zone are calculated at every step. Our results will be compared with the experimental and analytical models in the literature. On the whole, our study is concerned with the simulation of the thermally insulated filling of moulds in RTM process while adopting the CVFEM and VOF method, taking into account the presence of obstacles, coupled with the thickness variation effect and the reinforcement coats.