Week 2 - Flow over a Cylinder.

Objective: To simulate the flow of fluid (2D laminar) over a cylinder for varying Reynolds numbers and compute the Strouhal number, drag coefficient, lift coefficient, velocity contours and pressure contours.

Theory: The Karman vortex street happens due to vortex shedding. It happens when a flow encounters a cylindrical body and it results in the formation of periodic vortices after crossing the body. Vortex shedding has a frequency associated with itself which is linked with the Strouhal number.

Note: The solution would be assumed to be converged when lift coefficient `C_l` and drag coefficient `C_d` plots either converge or becoming periodic.

Preprocessing:

1. Meshing:
2. Named Selections:
3. Reference values:

(I realised that I forgot to change the reference velocity for the other Reynolds Numbers. As a result my `C_d` and `C_l` values have come out to be higher by a large factor. I realised it after preparing the report.)

Postprocessing:

1. Part 1
   1. `Re=100`
      
      1. Steady Solve
         1. Scaled Residuals:
         2. Velocity Contours:
         3. Pressure Contours:
         4. Cd:
         5. Cl:
         6. FFT
            1. Cd:
               1. Strouhal number corresponding to maximum magnitude `approx0`
            2. Cl:
               1. Strouhal number corresponding to maximum magnitude `approx0.015833333`
      2. Transient Solve
         1. Scaled Residuals:
         2. Velocity Contours:
         3. Pressure Contours:
         4. Cd:
         5. Cl:
         6. FFT
            1. Cd:
               1. Strouhal number corresponding to maximum magnitude `approx0`
            2. Cl:
               1. Strouhal number corresponding to maximum magnitude `approx0.083966412`
2. Part 2
   1. `Re=10` Steady Solve
      1. Scaled Residuals:
      2. Velocity Contours:
      3. Pressure Contours:
      4. Cd:
      5. Cl:
   2. `Re=1000` Steady Solve
      1. Scaled Residuals:
      2. Velocity Contours:
      3. Pressure Contours:
      4. Cd:
      5. Cl:
   3. `Re=10000` Steady Solve
      1. Scaled Residuals:
      2. Velocity Contours:
      3. Pressure Contours:
      4. Cd:
      5. Cl:
   4. `Re=100000` Steady Solve
      1. Scaled Residuals:
      2. Velocity Contours:
      3. Pressure Contours:
      4. Cd:
      5. Cl:

Table:

`Re`	`C_d` (Large due to unchanged reference velocity)
`10`	`0.033295457`
`100`	`1.3556183`
`1000`	`83.741896` (At the end of`1200` iterations)
`10000`	`8570.835` (At the end of `1200` iterations)
`100000`	`1033829.3` (At the end of `1200` iterations)

Reference: Numerical simulation of laminar flow past a circular cylinder - ScienceDirect