Dataset for 'Turbulent boundary layers over multiscale rough patches'
Vanderwel, C., Ganapathisubramani, B., Boundary Layer Meteorology, 2019

DOI for dataset: https://doi.org/10.5258/SOTON/D0769.
Creative Commons: Attribution 4.0 licence – CC BY

Abstract: We experimentally investigate the effects of multiscale rough patches on the drag and flow structure of a fully rough turbulent boundary layer in a wind tunnel. Several patches containing both organized and randomized arrangements of cubes of multiple sizes are tested in order to study the dependence of drag on the frontal solidity of the patch. The drag of each patch is measured with a drag balance for a range of Reynolds numbers, indicating a dependence of the drag on the frontal solidity following the trend predicted by Macdonald et al. (Atm Env, 1998, 32(11):1857-1864). One of the patches is also replicated with the smallest scales removed and measurements show that the smaller scales have negligible impact on the overall drag. Flow fields in several cross-sections are captured using particle image velocimetry and maps of the velocity deficit and increased turbulence activity in the wake of the patches are determined and used to define the extent of the internal boundary layer formed by each patch. 

The data is contained in separate folders, broken down by the different sections of the paper as follows:

1) Drag: contains an Excel file with all the drag measurements plotted in figure 4 & 10.

2) FlowProfiles: contains MATLAB figure files corresponding to figures 6 & 9.

3) PatchDesign-MATLAB: contains the design of the patches in MATLAB format. Run the script “DisplayRoughPatchLayout.m” to display each patch.

4) PatchDesign-STLs: contains STL files for each of the patches as well as a Solidworks file for the Sierpinksi patch.

5) PIV-StreamwiseMaps: contains maps of the flow field obtained using PIV in the streamwise-vertical plane over each patch as in figure 7. Run the script “DisplayMaps.m” to display each patch.

6) PIV-WakeMaps: contains maps of the flow field obtained using SPIV in the spanwise-vertical plane in the wake of each patch as in figure 8. Run the script “DisplayWakeDeficit.m” to display each patch.

7) PODs: contains MATLAB figure files of the proper orthogonal decomposition displayed in figures 11 & 12.