The demand for economic production of structural components made of continuous fiber reinforced plastics is still very challenging. Because of its high automation potential, Compression Resin Transfer Molding (CRTM) processes are increasingly investigated. To manufacture sandwich parts, a light-weight foam core can be embedded into the preform before resin infiltration. To prevent those core materials from crushing during mold filling, the cavity pressure must not exceed a specific limit. This limit can be assured by a pressure-controlled adjustment of cavity height while the resin infiltrates the preform. To predict the filling behavior and enable an optimization of this pressure-controlled-RTM (PC-RTM) process, numerical mold filling simulations are needed. As there is no state-of-the-art method available, a new method to simulate mold filling in PC-RTM using a three-dimensional finite-volume method is used, which is combined with a moving mesh to account for the change of cavity height during the process. The fluid pressure in the cavity is controlled by implementing a pressure-dependent formulation of the position of the upper mold boundary. ... mehrThe simulations are validated by experimental studies of a simple geometry. Furthermore an application example of a complex geometry is presented to demonstrate the numerical capability of the method.