2D flow around an oscillating cylinder - $Re_{H}= 185$

Numerical study based on the publication of Pham et al., Journal of Marine Science and Technology, Vol. 18, No. 3, pp. 361-368 (2010) 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 Come back to first page —– ==== Simulation settings ==== —- === 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) Come back to first page —- ==== Data features ==== —- * 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 Come back to first page —- ==== Database organisation ==== —- 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)

and - directory : CAS_F0.95_A0.2

and - directory : CAS_F0.95_A0.5

and - directory : CAS_F1.2_A0.2

and - 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)

Come back to first page