Week 2 - Flow over a Cylinder.

Aim :

Simulate the flow over a cylinder for various reynolds number and to observe the Vortex shading.

Vortex Shading :

It is a phonemon which occurs when air flows over a surface. A wavy structure of airflow flows beyond the surface.

The objective is to observe the vortex shading beyond the object.

Part - I Case Setup :

Geometry & Meshing :

The Meshing has been fined by various methods and a refined mesh is obtained for better accuracy of the solution.

Setup :

Both Steady state and transient simulations has been performed and the results were observed.

Steady State Simulation :

A new material has been created with Density 1 kg/m3 and Dynamic Viscosity 0.02 which makes the Reynolds number 100 (With Inlet velocity 1 m/s).
700 Iterations has been performed and the vortex shading has been observed.

Transient Simulation :

Transient simulation has been performed with 0.1 Step size for 500 time steps.

Residuals from the observation :

From the observed results, Strouhal number was calculated :

Strouhal number is calculated by St = fD/U

(0.125 * 2/1) =0.25

Transient Simulation :https://drive.google.com/file/d/1r1dc-iEtsUpkeSqbURpb8TKDU6ey2j_k/view?usp=sharing

Case II :

Re : 10

Drag Coefficent:

Lift Coefficient :

Re :100

Drag Coefficeint :

Lift Coefficeint :

Re : 1000

Drag Coefficient :

Lift Coefficient :

Re : 10000 :

Drag Coefficient :

Lift Coefficient :

Re : 100000

Drag Coefficient ;

Lift Coefficient :