Direct numerical simulation dataset of turbulent inflow for the hydrogen fueled Darmstadt multi-regime burner

The dataset provides turbulent inlet boundary conditions for the hydrogen-fueled Darmstadt multi-regime burner, obtained from direct numerical simulations performed with nekRS. It includes flow data for outer slot 2 and the central pipe, assuming perfectly premixed hydrogen–air mixtures. Consequently, species transport is not considered. The following operating conditions are provided: Supply stream Inner diameter $D_\mathrm{i}$ Outer diameter $D_\mathrm{o}$ Bulk velocity $\bar{U}$ Equivalence ratio $\phi$ Central pipe (-) 3 mm 105 m/s 1.4, 2.2, 3.5, 9 Slot 2 35 mm 45 mm 20 m/s 0.26 For each flow configuration, the data is provided as a separate .zip archive. Pipe flow cases are distinguished by the equivalence ratio included in the file name. Each dataset contains: a CSV file (*_mean.csv) containing the mean radial profile of the axial velocity component in meters per second. The radial distance from the centerline is given in meters. Since the flow is wall-bounded and no swirl is imposed, the mean radial and circumferential velocity components are zero. A visualization of the mean axial velocity profile is provided in fig_mean-velocity-profile.png. a CSV file (*_rms.csv) containing the radial profiles of the root-mean-square (RMS) values of all three velocity components in meters per second. The radial distance from the centerline is given in meters. The RMS profiles of the axial velocity component is illustrated in fig_root-mean-square-profile.png. an HDF5 (*_inflow_data.h5) file containing instantaneous cross-sectional flow snapshots. The snapshots span five flow-through cycles, corresponding to 1.714 ms for the pipe flow and 9 ms for the slot 2 flow, resolved by 1201 and 526 snapshots, respectively. The data can be accessed through the following keys: time: timestamps of the snapshots in seconds, stored as an $N_t \times 1$ array for the $N_t$ samples. points: cartesian grid coordinates (x,y,z) in meters, stored as an $N_p \times 3$ array. All points lie in the xy-plane. velocity: cartesian velocity components in meters per second, stored as an $N_t \times N_p \times 3$ array. Example visualizations are provided in fig_cross-section-samples.png. See the accompanying README file for further details on dataset structure and usage.