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In order to effectively capture the vortex shedding, a small enough timestep was needed. It was recommeded to have roughly 20 - 25 timesteps per cycle hence we used a timestep of .2. The resulting plot in the numerical results showing how the lift coefficient oscillated due to the vortex shedding is shown below. To compare the effect of the timestep size, we continue to plot the lift coefficient after the oscillations have been established with a timestep of .02 seconds. Changing the timestep changes the resolution, so with a smaller timestep we expect a better resolution when seeing the oscillation of the lift coefficient. 

Timestep = .2 s

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Timestep = .2 -> .02s

You can notice here how the shedding is captured much more effectively using a timestep of .02. 

We also run the simulation with a timestep of 1s. Notice how we see a smooth curve for the lift coefficient, rather than the oscillations due to the vortex shedding.

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