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2D flow around an oscillating cylinder - $Re_{H}= 185$
The motion of the cylinder is vertical and forced with a sinusoïdal function
*Author : Y. Fraigneau, LISN, UMR CNRS 9015 (yann.fraigneau@lisn.fr)
Date : July 2016
Simulation type : DNS (code Sunfluidh – Sunfluidh code)
Location : /DATABASE_2DFLOW_AROUND_OSCILLATING_CYLINDER_DNS
Status : Free access for laboratory members, on request for external members
Data size : ~ 7 Gb
A video is available here
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==== Simulation settings ====
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=== 2D sketch ===
=== Referential : cartesian geometry ===
- axes :
* x(i) : downstream direction
* y(j) : normal direction
- origin :
* $x_0= 0$ : centre of the cylinder
* $y_0= 0$ : mid-height
=== Reference scales ===
* Density : mass density of the fluid ($\rho_0$)
* Length : cylinder diameter ($D$)
* Velocity : velocity at inlet ($U_0$)
* Dynamic viscosity : dynamic viscosity of the fluid ($\mu_0$)
* Reynolds number : $Re_H= \frac{\rho_0.U_0.D}{\mu_0}= 185$
* Strouhal number : $St_0=\frac{f}{f_0}$ (oscillating-cylinder frequency $f$ over vortex-shedding frequency $f_0$ when the cylinder is at rest)
* motion magnitude : $A \times D$ (where A is the motion factor)
=== Non-dimensionalised data ===
* velocity : $U^*=\frac{U}{U_0}$
* density : $\rho^*= \rho/\rho_0= 1$
* coordinates : $x*=\frac{x}{D}$, $y^*=\frac{y}{D}$
=== Computational domain ===
- Domain scope
- computational domain size
* Downstream direction(x) : $L_x^*= 90.0$ (upward part $L_u= 40$, downward part $L_d=50$)
* Normal direction (y) : $L_y^*= 80.0$
- Oscillating cylinder (vertical oscillating motion around the mid-height of the domain)
* centre position at rest : $x_c= 0.0$ and $y_c= 0.0$
* diameter: $D^*= 1$
* oscillation frequency : $St= 0.95$ or $St= 1.2$
* The cylinder is modeled with a pseudo-penalisation method (Pasquetti et al., Applied Numerical Mathematics, 2008)
- Boundary conditions
* Inlet : imposed pressure uniform velocity ($U_0=1$)
* Outlet : Orlansky type
* Bottom and top conditions : symmetry
- Spatial resolution
* mesh size : $480 \times 480 $ (576.000 cells)
* About cell-size
* $\Delta x*$ : from $0.0125$ to $0.78785$$ (downstream direction)
* $\Delta y*$ : from $0.0125$ to $0.65924$ (normal direction)
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==== Data features ====
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* Time series
* from probes
* Physical quantities : velocity components along x and y directions (u,v) and pressure (p)
* 1 probe
* Time step= $2 \,10^{-2}$ time unit
* Time range : 400 to 600 time units
* Location : Xi= 3.5 , Xj=0.0
* File name (per physical quantity): x_ins_00000.d with x= u,v,p
* about cylinder motion
* center position as a function of time (ASCII file ibm_position01.dat)
* cylinder velocity as a function of time (ASCII file ibm_velocity01.dat)
* global force components applied to the cylinder (ASCII file ibm_force01.dat)
* force contributions exerted on the moving cylinder (ASCII file ibm_force_contribution01.dat, the four last columns can be ignored)
* 3D snapshots
* Instantaneous fields : velocity components in x, y and z directions (U,V), the pressure (P) and the phase function related to the body motion (TRACE)
* Recording rate : 0.4 time unit
* Time range from from 200.0 to 600.0 time units
* File name : res_xxxxx_yyyyyyy.d
* MPI subdomain ID: 0
* Time ID : from 3 to 502
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==== Database organisation ====
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Data size : ~ 7 Gb
Main directory** : /vol/DATABASE_MECA/DATABASE_2DFLOW_AROUND_OSCILLATING_CYLINDER_DNS
For more details about files, see the wiki doc of Sunfluidh
Intermediate directories (four cases of study)
- $St= 0.95$ and $A= 0.2$ - directory : CAS_F0.95_A0.2
- $St= 0.95$ and $A= 0.5$ - directory : CAS_F0.95_A0.5
- $St= 1.20$ and $A= 0.2$ - directory : CAS_F1.2_A0.2
- $St= 1.20$ and $A= 0.5$ - directory : CAS_F1.2_A0.5
Endpoint directories & files
/DATASETUP : ASCII files input data file for sunfluidh : input3d.dat /GRID : ASCII files input data file : data_meshgen.d grid files for sunfluidh: maillx.d, mailly.d, maillz.d /SNAPSHOTS : snapshots binary files res_xxxxx_yyyyyyy.d /TIMESERIES : ASCII files u_ins_00000.d , v_ins_00000.d and p_ins_00000.d (timeseries of the velocity components and pressure from probe) ibm_position01.dat, ibm_velocity01.dat (about cylinder motion) ibm_force01.dat, ibm_force_contribution01.dat (about forces exerted on the cylinder)
- fr