Table des matières
3D forward-facing step flow at $Re_H= 8304$ (turbulent inflow)
Database in progress … it is currently uncompleted
Author : Y. Fraigneau, LISN, UMR CNRS 9015 (yann.fraigneau@lisn.fr)
Date : August 2020
Simulation type : DNS (code Sunfluidh – Sunfluidh code)
Location : DATABASE_FORWARDFACINGSTEPFLOW2_RE8000_DNS
Status : Restricted access
Data size : ~ 8.6 Tb
Simulation settings
2D sketch
Referential : cartesian geometry
- axes :
- x(i) : downstream direction
- y(j) : normal direction
- z(k) : spanwise direction
- origin :
- $x_0= 0$ : the step
- $y_0= 0$ : the bottom wall of the domain
- $z_0= 0$ : the left side of the computational domain
Reference scales
- Density : mass density of the fluid ($\rho_0$)
- Length : step height ($H$)
- Velocity : inlet bulk velocity ($U_i$)
- Dynamic viscosity : dynamic viscosity of the fluid ($\mu_0$)
- Reynolds number : $Re_H= \frac{\rho_0.U_0.H}{\mu_0}= 8304$
Non-dimensionalised data
- velocity : $U^*=\frac{U}{U_i}$
- density : $\rho^*= \rho/\rho_0= 1$
- coordinates : $x*=\frac{x}{H}$, $y^*=\frac{y}{H}$ , $z^*=\frac{z}{H}$
Computational domain
- Domain scope
- Downstream direction(x) : $L^*= 37.0$
- Normal direction (y) : $H_t^*= 22.0$
- Spanwise direction (z) : $l^*= \pi$
- Step position : $L_s^*= 17.0$
- Step height : $H^*= 1$
- Boundary conditions
- Inlet : Turbulent boundary layer at $X_{in}^*= -17.0$, $\delta_{in}= \frac{H}{3}$ (boundary layer's thickness)
$Re_{\theta}=300$, fluctuations generated from the SEM approach. - Outlet : Orlansky's type at $X_{out}^*= 20.0$
- Wall conditions : Top and low walls of the domain
- Periodicity : lateral ends of the domain
- Domain decomposition (200 MPI subdomains)
- Along the downstream direction :
- 15 (between the inlet and the outlet, above the step)
- 10 (between the inlet and the step)
- Along the normal direction : 4
- Along the spanwise direction : 4
- 2D sketch of domain decomposition in a plan {xy} (MPI process distribution (1))
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 0 0 0 0 0 0 0 0 0 0
- Spatial resolution
- Grid : $128 \times 192 \times 96$ per subdomain (471.859.200 cells over the domain)
- About cell-size
- $\Delta x_{min}^*= 1.0 \, 10^{-2} \quad \Delta x_{max}^*= 2.5 \,10^{-2}$ (downstream direction)
- $\Delta y_{min}^*= 1.5 \, 10^{-3} \quad \Delta y_{max}^*= 7.5 \,10^{-2}$ (normal direction)
- $\Delta z_{min}^*=\Delta z_{max}^*= 8.18123 \, 10^{-3}$ (spanwise direction)
Data features
- Time series from probes : U,V,W,P (velocity components & pressure)
- Physical quantities : velocity components along x, y and z directions (u,v,w) and pressure (p)
- 5 probes
- Time step= 0.00945 time unit
- Time range : from 120 to 700 time units
- Locations (In vertical plan at $z=1.57$)
- Xi=-0.250 , Xj= 0.250 , Xk= 1.57 - MPI Subdomain ID :
- Xi= 0.125 , Xj= 1.125 , Xk= 1.57 - MPI Subdomain ID :
- Xi= 1.000 , Xj= 1.125 , Xk= 1.57 - MPI Subdomain ID :
- Xi= 1.000 , Xj= 1.250 , Xk= 1.57 - MPI Subdomain ID :
- Xi= 4.000 , Xj= 1.125 , Xk= 1.57 - MPI Subdomain ID :
- File name (per physical quantity): x_ins_yyyyy.d with x= u,v,w,p and 'yyyyy' the MPI subdomain ID
- 3D snapshots
- Instantaneous fields : velocity components in x, y and z directions (U,V,W) and pressure (P)
- first dataset :
- Recording rate : 0.5 time units
- Time range from 120 to 729 time units
- File name : res_xxxxx_yyyyyyy.d (xxxxx : MPI subdomain ID, yyyyyyy : Time ID)
- MPI subdomain ID: from 0 to 199
- Time ID : from 53 to 1270
- 2D slices
- Instantaneous fields : velocity components in x, y and z directions (U,V,W) and pressure (P)
- Recording rate : 0.1 time units
- Time range from 120 to 729 time units
- 4 slices are considered :
- slice 1 : normal direction z - position : z= 1.57 - MPI subdomains ID :
- MPI subdomains ID : 1 to 197
- slices 4,5,6 : Wall pressure only
- File name : slice_n_idir_xxxxx_yyyyyyy.d (n : slice number ID, idir : direction= 1: x(i), 2: y(j), 3: z(k), xxxxx : MPI subdomain ID, yyyyyyy : Time ID)
- slice 4 : normal direction y - position : y= 0.0 WARNING : available only from Time ID = 139 (corresponding to time > 386)
- slice 5 : normal direction x - position : x= 0.0
- slice 6 : normal direction y - position : y= 1.0
- MPI subdomains ID : 4 to 7
- MPI subdomains ID : 20 to 23
- MPI subdomains ID : 36 to 39
- MPI subdomains ID : 52 to 55
- MPI subdomains ID : 68 to 71
- MPI subdomains ID : 80 to 83
- MPI subdomains ID : 92 to 95
- MPI subdomains ID :104 to 107
- MPI subdomains ID :116 to 119
- MPI subdomains ID :128 to 131
- MPI subdomains ID :140 to 143
- MPI subdomains ID :152 to 155
- MPI subdomains ID :164 to 167
- MPI subdomains ID :176 to 179
- MPI subdomains ID :188 to 191
- Time ID : from 54 to 6363
- Statistics
- fields : (i,j : indexes of direction x, y or z)
- Mean fields of velocity components (<Ui>) and pressure (<P>)
- Mean fields of quadratic quantities (<P2>, <UiUj>)
- Time and space average computation (along the spanwise direction)
- Time startup = 100.0 time units
- Time range per file = 20.0 time units
- Total time range from 100.0 to 720 time units
- file name : rst_xxxxx_yyyyyyy.d (xxxxx : MPI subdomain ID, yyyyyyy : Time ID)
- MPI subdomain ID : from 0 to 49 (MPI process rank where results about space average computation are stored)
- Time ID : from 1 to 31
Database organisation
Data size : ~ 8.6 Tb
Main directory : /vol/DATABASE_MECA/RESTRICTED_ACCESS/DATABASE_FORWARDFACINGSTEPFLOW2_RE8000_DNS
For more details about files, see the the wiki doc of Sunfluidh
Directories & files
/GRID : contains all ASCII files about grid setup
input data file : data_meshgen.d
report on grid features : report_meshgen.d
grid files for sunfluidh: maillx.d, mailly.d, maillz.d
check files (ASCII) : check_mesh_I.d,check_mesh_J.d,check_mesh_K.d
(3 columns : indices, cell-face coordinates, cell size)
/DATASETUP : ASCII files
input data file for sunfluidh : input3d.dat
data file for MPI subdomain distribution (MPI graphical topology): data_mpi_subdomain_layout.dat
/TIMESERIES : contains time series recorded over the time range [120,680]
ASCII files : x_ins_yyyyy.d with x= u,v,w,p
time series files are sliced in storage directories CAS-MPI200-n (n from 53 to 255)
/SNAPSHOTS : snapshots binary files res_xxxxx_yyyyyyy.d with a recording rate of 0.5 time unit
files stored in archive files : res_yyyyyyy.tar for each time ID
/STATISTICS : statistics binary files files rst_xxxxx_yyyyyyy.d
files stored in archive files : res_z.tar , z is an ID number (from 1 to 31)
/SLICES : slice binary files slice_n_idir_xxxxx_yyyyyyy.d
files stored in archive files : slices_z.tar , z is an ID number (from 53 to 255)
/RESTART_AR : backup/restart archive save_t145.tar and save_t45.tar at time=145 and 454 respectively