DOI: 10.4121/07267e2b-58a2-4600-9821-2b6648cb423a
title: Supplementary benchmark data and case settings for "Wake interaction of dual surging FOWT rotors in tandem"

description: Providing the animations, data of result outcomes, simulation case settings, and source code for "Wake interaction of dual surging FOWT rotors in tandem".<br>Educational and research use of the material is permitted. Please cite the following reference when using/expanding the code, graphics and data:<br>Y. Li, W. Yu, H. Sarlak, "Wake interaction of dual surging FOWT rotors in tandem", Renewable Energy (2025).<br>################################The CFD simulations were perform using OpenFOAM v2106<br>For referring, below are the modules loaded<br>module swap gcc/10.3.0-binutils-2.36.1module swap mpi/4.1.1-gcc-10.3.0-binutils-2.36.1module load OpenFoam/v2106/gcc-10.3.0-binutils-2.36.1-openmpi-4.1.1<br>################################ANIMATIONS<br>Stored in directory "animations".<br>Animations of streetwise velocity (u, "XXXX_Vel.mp4") and out-of-plane velocity (omega_y, "XXXX_Vor.mp4") fields on plane y/D = 0.0 for various cases listed in Table 1. The time length of all the animations cover 2 complete surging cycles (~10s), which are the 54th and 55th surging cycle after starting the simulations. t = 0s is shifted to the start of the 54th surging cycle for convenience.<br>In the top of each panel, time (t, omega_S is the surging frequency), surging velocity of the upstream rotor (V_S^{up}), and surging velocity of the downstream rotor (V_S^{down}) are indicated. On the left, case number, fixed-surging configuration or surging phase angle difference (Delta_{phi_{S_0}}), and inflow conditions are indicated.<br>These animations are compressed using file format of mp4. Uncompressed images used to make the animations can be found in directory "dataPNGs/sourcePNGsForAnimation". Each surging cycle consists of 48 images.<br>"3D_FS_LamTurb_XXX.mp4" presents the cases with different fixed-surging configuration with interspacing of 3D. 3L1 to 3L4 and 3T1 to 3T4 are included.<br>"5D_FS_LamTurb_XXX.mp4" presents the cases with different fixed-surging configuration with interspacing of 5D. 5L1 to 5L4 and 5T1 to 5T4 are included.<br>"3D_DEG_LamTurb_XXX.mp4" presents the cases with different surging phase angle differences with interspacing of 3D. 3L4 to 3L8 and 3T4 to 3T8 are included.<br>################################CASE SETTINGS<br>Stored in directory "caseSettingsCodes/tutorial".<br>Most of the cases settings appeared in the manuscript can be found in directory "tutorial". Every case used 64 processor and ran for around 66 hr to complete (Lenovo ThinkSystem SD530 with the processors being Intel Xeon Gold 6126, see Ref. [28] for more details on the hardware we used). Job script used by the author is provided ("jobsubmit_gbar_Clem2"). Execute file "meshing_script" to make the mesh. Note that the mesh for turbulent inflow cases were different form the laminar inflow cases, there might be some mistake in the case setting file as the author rely heavily on copying while executing the cases (we are sure that case "5T1" and "5L3" have the correct mesh settings). Note that the cases were set mostly through modifying file "parameterMaster". Note that some of the parameters are actually useless, they are there for "historical reasons".<br>################################SOURCE CDOE<br>Stored in directory "caseSettingsCodes/src".<br>Source code for the library used is provided in directory "src". Note that the source code was a modified version of turbinesFoam developed by Bachant et al., their README file and license are included as "README_from_turbinesFoam" and "LICENSE_from_turbinesFoam", respectively. Execute "Allwmake" and the library should be compiled automatically (file "libsurgingTurbinesFoam.so" should be generated somewhere depend on how the path is set). If it gives errors, one may have to check the path setting that depends on the machine one uses (in the file "src/Make/files"). Note that in the source code, many lines/variables are not used, they are there for "historical reasons".<br>################################DATA<br>Data presented in the publication can be found in the directory "dataPNGs/selectedData"<br>Entering this directory, one can find directories named in the case name provided in Table 1 in the manuscript. Selected results of all cases are available.<br>Entering case directory, one can find directories "exportedCSVs" and "postProcessing/turbines/0".<br>"exportedCSVs" saves the sectional data in csv format (check the first few lines to see the file structure), they are used to plot contour plots in the manuscript. The file names of the csv files are self explainable. "...PlanePhase000.csv" indicates the data is phase-averaged based on phi_S^{down} = 0.0 pi, while "...PlanePhase180.csv" indicates the data is phase-averaged based on phi_S^{down} = 1.0 pi (data of phase-averaging based on phi_S^{down} = 1.0 pi are not presented in the manuscript).<br>"turbines" saves the integral properties of turbines output for both the upstream and the downstream rotor. Entry "time" is simulation time, "angle_deg" is the rotational phase angle (phi_{Omega}) in degree, "cp" is the power coefficient, "cd" is the thrust coefficient (ref wind speed for upstream and downstream rotor were 11.4 m/s and 7.6 m/s, respectively. Notice this is different than what it was presented in the manuscript). Note that some entries are not used, they are there for "historical reasons" (check the source code).<br>################################SOURCE IMAGES FOR ANIMATIONS<br>Stored in directory "dataPNGs/sourcePNGsForAnimation".<br>Source images for animations are provided in directory "sourcePNGsForAnimation" hoping to make comparing different time steps easier. Executable file "makeVideo" is included in each sub directory. The file was used to create the mp4 files in "animations".