Dataset for DNS-based characterization of pseudo-random roughness in minimal channels
1; Stroh, Alexander 1; Chung, Daniel; Forooghi, Pourya1 Institut für Strömungsmechanik (ISTM), Karlsruher Institut für Technologie (KIT)
Abstract:
It is demonstrated that both roughness function ($\Delta U^+$) and zero-plane displacement can be predicted within $\pm5\%$ accuracy using DNS in properly sized minimal channels. Notably, the predictions do not deteriorate when a limited range of large horizontal roughness scales are filtered out due to the small channel size (here up to 10\% of original roughness height spectral energy based on 2D PS). Additionally, examining the results obtained from different random realizations of roughness shows that a certain combination of PDF and PS leads to a nearly unique $\Delta U^+$ for deterministically different surface topographies.
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| Zugehörige Institution(en) am KIT | Institut für Strömungsmechanik (ISTM) |
| Publikationstyp | Forschungsdaten |
| Publikationsdatum | 12.05.2022 |
| Erstellungsdatum | 01.07.2021 |
| Identifikator | DOI: 10.5445/IR/1000142136 KITopen-ID: 1000142136 |
| Lizenz | Creative Commons Namensnennung 4.0 International |
| Schlagwörter | DNS, Roughness, Minimal channel |
| Liesmich | These files contain the data used in the publication: “DNS-based characterization of pseudo-random roughness in minimal channels” Numerical Details: The carried out DNS is based on a pseudo-spectral solver for incompressible boundary layer flows developed at KTH/Stockholm. The Navier-Stokes equations are numerically integrated using the velocity-vorticity formulation by a spectral method with Fourier decomposition in the horizontal directions and Chebyshev discretization in the wall-normal direction. For temporal advancement, the convection and viscous terms are discretized using the 3rd order Runge-Kutta and Crank-Nicolson methods, respectively. The simulation domain represents an turbulent channel flow with periodic boundary conditions applied in streamwise and spanwise directions, while the wall-normal extension of the domain is bounded by no-slip boundary conditions at the upper and lower domain wall. The flow is driven by a prescribed constant pressure gradient (CPG). The friction Reynolds number for the present case is fixed to Re_τ = 500. The structured surface is introduced through an immersed boundary method (IBM) based on the method proposed by Goldstein et al. (1993) and is essentially a proportional controller which imposes zero velocity in the solid region of the numerical domain. Data Files: The data files are saved and labeled in *.mat files. Each file contains MATLAB data consisting of the roughness height distribution and corresponding coordinates. The roughness structures are non-dimensionalized with the channel half height δ. Reference: Please provide a reference to the article above when using this data. |
| Art der Forschungsdaten | Dataset |
| Relationen in KITopen |