This dataset provides the complete simulation cases and corresponding results used in the master’s thesis “Mixed-dimensional flow coupling with preCICE” at the Technical University of Munich, by Francisco Javier Martínez Quiles. The archive accompanies the thesis and is intended to support transparency, reproducibility, and further analysis of partitioned mixed-dimensional fluid flow simulations performed using preCICE. The upload consists of four main archives: simulation-cases.tar.gzContains the full set of runnable simulation cases, including solver configurations, coupling setups, run and clean scripts, and auxiliary tools. The cases cover multiple benchmarks and coupling configurations, including 1D–2D, 1D–3D, and 2D–3D fluid–fluid coupling for pipe and duct geometries, as well as transient water-hammer scenarios. results.tar.gzContains the corresponding simulation outputs, post-processed data, and visualization material. This includes extracted time series (pressure, velocity, and axial evolution), data files, and figures used for analysis and comparison in the thesis. precice-multiscale-weighted-collect-extensions.tar.gz Contains the modified preCICE source files implementing the geometry-weighted “collect” extension of the axial geometric multiscale mapping used in selected 1D–2D and 1D–3D configurations of the partitioned pipe benchmark case only. These files are intended to be applied as a patch to the preCICE version provided in this upload (precice-8e8fbde.tar.gz, commit 8e8fbde5984fd046ee03bf2c07810f02fb500b90) and are required to reproduce the weighted-collect results presented in the thesis. precice-8e8fbde.tar.gz Provides a snapshot of the preCICE source code at commit 8e8fbde5984fd046ee03bf2c07810f02fb500b90. This snapshot serves as the reference base version for applying the weighted-collect patch and reproducing the results. For further details, see the README.md files contained in each archive.