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datasetmeca:ffsflow_1

Ceci est une ancienne révision du document !


3D forward-facing step flow at $Re_H= 8000$

Database in progress … it is currently uncompleted

Author : Y. Fraigneau CNRS-LIMSI (yann.fraigneau@limsi.fr)
Date : August 2020
Simulation type : DNS (Sunfluidh code)
Location : DATABASE_FORWARDFACINGSTEPFLOW1_RE8000_DNS
Status : Restricted access


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Simulation settings


2D sketch

Referential : cartesian geometry

  1. axes :
    • x(i) : downstream direction
    • y(j) : normal direction
    • z(k) : spanwise direction
  2. 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 : $Re_H= \frac{\rho_0.U_0.H}{\mu_0}= 8000$

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

  1. Domain scope
    • Downstream direction(x) : $L^*= 34.0$
    • Normal direction (y) : $H_t^*= 22.0$
    • Spanwise direction (z) : $l^*= \pi$
    • Step position : $L_s^*= 14.0$
    • Step height : $H^*= 1$
  1. Boundary conditions
    • Inlet : Blasius' profile at $X_{in}^*= -14.0$, $\delta_{in}= \frac{H}{3}$ (boundary layer's thickness)
    • Outlet : Orlansky's type at $X_{out}^*= 20.0$
    • Wall conditions : Top and low walls of the domain
    • Periodicity : lateral ends of the domain
  2. 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
  3. 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)

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Data Recording : information about data types


  • 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= 0.0126 time unit
    • Time range : 188.37 to ?? 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)
    • Recording rate : 0.9 time units (until time= 300.877) - 0.3 time units (until time= ??)
    • Time range from 189.877 to ?? 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 69 to ??
  • 2D slices
    • Instantaneous fields : velocity components in x, y and z directions (U,V,W) and pressure (P)
    • Recording rate : 0.3 time units
    • Time range from from 189.877 to ?? time units
    • 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)
      • MPI subdomain ID: ??
      • Time ID : from 748 to ??
  • 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 = 200.0 time units
    • Time range per file = 10.0 time units
    • Total time range from 200.0 to ?? 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 ?

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Database organisation


Data size : ~ ?? To
Main directory : /vol/DATABASE_MECA/RESTRICTED_ACCESS/DATABASE_BACKFACINGSTEPFLOW_RE6000_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 [188.37,??]
                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 130 to ??)
   
  /SNAPSHOTS  : snapshots binary files res_xxxxx_yyyyyyy.d
                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 ??)
                
  /SLICES     : slice binary files slice_n_idir_xxxxx_yyyyyyy.d
                files stored in archive files : slices_z.tar , z is an ID number (from 131 to ??)
               
  /RESTART_AR : backup/restart archive save.tar at time ??
  

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Traductions de cette page:
datasetmeca/ffsflow_1.1606143693.txt.gz · Dernière modification : 2020/11/23 16:01 de yann

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