Material and energy efficiency are now crucial to combat recent climate challenges. In lightweight construction, additive manufacturing techniques, such as the Tailored Fiber Placement (TFP) technology enables precise, curvilinear fiber placement, making them well-suited for applications requiring lightweight anisotropic composites. By allowing fibers to be strategically oriented along stress trajectories, TFP facilitates the efficient use of materials while reducing overall weight and thus obtain sustainable solutions. For the infiltration of TFP components in resin transfer molding (RTM) processes, the complex architecture of the reinforcements poses a special challenge [1]. Therefore, the development of meso-scaled models of the fiber architecture that account for production-specific characteristics is essential to conduct molding simulations for virtual process design. These models must reflect the influence of TFP-specific morphological characteristics, like the positioning of the sewing threads and base material as they affect the local fiber orientation, undulation and fiber volume content of the composite. This work introduces an explicit modeling approach for the TFP process using simplified geometric structures. The aim is to predict the process-induced mesostructure and provide a basis for understanding the interaction between rovings and sewing thread. These models are used to investigate the resin flow through TFP structures which is highly influenced by the cavities and undulations caused by the TFP production method. We present models for various thread architectures. All models are calibrated using 3D scans on TFP composites. The findings contribute to the development of process-dependent infiltration models that are beneficial for optimizing the manufacturing of TFP-based composites and their associated RTM processes. The authors acknowledge funding from the DFG under project KA 4224/4-2 and SP 1646/2-2, Grant Number 415041798. [1] L. Bittrich, J. Seuffert, S. Dietrich, K. Uhlig, T.d.V. Lisboa, L. Kärger, and A. Spickenheuer, On the Resin Transfer Molding (RTM) Infiltration of Fiber-Reinforced Composites Made by Tailored Fiber Placement, Polymers 2022, 14(22), 4873; https://doi.org/10.3390/polym14224873