cfd-vv-suite

Data Provenance

How reference data was obtained

Analytical solutions

Exact formulas from the literature were evaluated at specified grid points using Python/NumPy scripts. For series solutions (e.g., Poiseuille-3D square duct, Bingham plug flow), 30–50 terms were summed to achieve double-precision accuracy (relative error < 1e-12).

MMS (Method of Manufactured Solutions)

Manufactured solutions were analytically differentiated to compute convective, pressure gradient, and viscous terms. Source terms were evaluated from these derivatives and verified by symbolic differentiation with SymPy for a subset of cases.

Experimental data

Experimental profiles were digitized from published figures using WebPlotDigitizer. The digitization resolution was chosen to exceed the published measurement uncertainty. Integral quantities (Cd, St, Nu) were taken directly from tables in the cited papers. Values are quoted with uncertainties where provided by the original authors.

Key experimental sources:

Case Source Method
Cylinder Re=20,40,100 Tritton (1959), Dennis & Chang (1970), Grove et al. (1964) Cd from force balance; Cp from surface taps
Lid-driven cavity (Ghia) Ghia et al. (1982) Tabulated numerical benchmark (Tables I and II)
Flat plate TBL (NASA TMR import) Karman-Schoenherr correlation; Coles profile (Bardina et al., NASA TM 110446) Theoretical correlations downloaded from NASA TMR
Cylinder Re=3900 Norberg (2003), Parnaudeau et al. (2008) PIV wake profiles; hot-wire for St
Backward-facing step (laminar) Armaly et al. (1983) LDA velocity measurements
Backward-facing step (turbulent) Driver & Seegmiller (1985) Pitot tube + hot-wire; Cf from Preston tubes
Flat plate TBL Wieghardt (1947) via Coles & Hirst (1968) Pitot tube mean velocity profiles
NACA 0012 McCroskey (1987), Gregory & O’Reilly (1970), Ladson (1988) Wind tunnel force balance + pressure taps
RAE 2822 Cook et al. (1979), AGARD AR-138 Wind tunnel pressure taps at M=0.73,0.75
NASA hump Greenblatt et al., CFDVAL2004 Wind tunnel PIV + pressure taps
Ahmed body Ahmed et al. (1984), SAE 840300 3/4 open-jet wind tunnel, sting balance
FSI2 Turek & Hron (2006) Computational benchmark (high-resolution FEM)
VIV Khalak & Williamson (1997) Water channel, LVDT for displacements
Oldroyd-B contraction Alves et al. (2001) Computational benchmark (high-resolution FVM)
Natural convection de Vahl Davis (1983), Fusegi et al. (1991) Computational benchmark (finite-difference)

DNS data

Mean profiles from DNS databases were extracted from published tables and figures. For the channel flow cases (Re_tau = 180, 550, 1000), data was taken from Moser, Kim, Mansour (1999) and Lee & Moser (2015). Values are time- and space-averaged over statistically stationary flow.

Accuracy and Limitations

Verifying the Data

All reference CSV files in reference/ are self-consistent: comparing cfdvv compare with the reference file as both result and reference yields zero error (or < 1e-12 due to floating-point rounding).

To verify a specific dataset:

cfdvv compare tools/cfdvv/cases/.../case-dir -r tools/cfdvv/cases/.../case-dir/reference/analytical/solution.csv --no-plot
# All field errors should be 0.000000e+00