Juan Sillero

======================================================================= INFORMATION ABOUT THE DNS DATABASE (HDF5 FILES) ======================================================================= This directory tree contain some of the restart files of a direct numerical simulations of fully developed ZPG Boundary Layer flow (Re_theta=2780-6650). Details are offered below. The algorithm used is presented in: - M. P. Simens, J. Jimenez, S. Hoyas, Y. Mizuno "A high-resolution code for turbulent boundary layers" Journal of Computational Physics Volume 228, Issue 11, 20 June 2009, Pages 4218-4231 - G. Borrell, J.A. Sillero, J. Jimenez "A code for direct numerical simulation of turbulent boundary layers at high Reynolds numbers in BG/P supercomputers" Computers & Fluids, Volume 80, 10 July 2013, Pages 37-43 The data is discussed in: - J.A. Sillero, J. Jimenez, R.D. Moser "One-point statistics for turbulent wall-bounded flows at Reynolds numbers up to \delta^+pprox2000" Phys. Fluids 25, 105102 ----------------------------------------------------------------------- STRUCTURE OF THE FILES: ----------------------------------------------------------------------- The files are written in HDF5 format, which is supported by most of the mathematical programs. For programming languages, libraries can be downloaded for C, C++, Fortran 90, and Java interfaces. The primitive variables {u,v,w,p} are stored in Fourier space as: (kz,ny,nx) ---> ( Fourier - Physical -Physical ) For instance, one file contains: Re Dataset {1} : Inverse of the viscosity used in the code, which defines the scaling in which the code works. Variable Dataset {SCALAR} : Variable recorded "u", "v", "w" or "p". procs Dataset {536} : Number of nodes used to run the simulation. (first element of the vector!) cfl Dataset {1} : Courantâ€“Friedrichsâ€“Lewy condition at which the simulation was run. dt Dataset {1} : Time step in code units for this flow realization. tiempo Dataset {1} : Time stamp in code units for this flow realization. timeinit Dataset {1} : Initial time stamp in code units (=0). lx Dataset {1} : Defines the streamwise length Lx of the box, in code units. ly Dataset {1} : Defines the wall-normal length Ly of the box, in code units. lz Dataset {1} : Defines the spanwise length Lz of the box, in code units. nx Dataset {1} : Number of collocation points in the streamwise direction. ny Dataset {1} : Number of collocation points in the wall-normal direction. nz2 Dataset {1} : Half the number of complex Fourier Gallerkin modes in z-> K_z[0:nz2] We use the 2/3 dealiasing rule in z, so the number of collocation points in those directions are 3/2 times the number of Fourier Gallerkin modes, and the extra modes are padded with zeroes. xout Dataset {1} : Location of the recycling plane. um Dataset {536} : Mean streamwise velocity profile in code units at the recycling station "xout". y Dataset {537} : Non-uniform grid for the wall-normal distance; in code units. Note that, because of the staggered grid: y=(-y1,0,y1,y2,....) value Dataset {15361, 536, 2730}: Primitive variable in code units. The array is stored in single-precision as [1:2*(nz2+1),1:Ny,1:Nx], equivalent to the complex array [Kz,Ny,Nx] SKETCH: ------v2------ * y(3)=y1 | | u2-----> x o w2,p2 x -----> | | | | ==================v1=========== * ======== y(2)=0; | | | | u1-----> x o w1,p1 x -----> | | -------------- * y(1)=-y1 Before final publication of a paper citing these data, please check this site (http://torroja.dmt.upm.es/turbdata/blayers/high_re) for an up-to-date reference. Please report any problems with the data, queries or doubts to J.A. Sillero, sillero@torroja.dmt.upm.es