Steady Vs Unsteady flow over a cylinder
Part I
Sr= Strouchal Number= `Sr=fl/U`
f= Frequency
Stouhal No.for Unsteady flow for Re 1oo is equal to 3.5
while for steady-state we can't calculate Sr, because frequency depends on time, and study calculation is independent of time.
Part II
| Re | Drag | Avg. Lift |
| 10 | 3.34 | 0.0007 |
| 100 | 1.35 | -0.02011 |
| 1000 | 1.19 | -0.06717 |
| 10000 | 1.02 | 0.014043 |
| 100000 | 0.67 | 0.003888 |
A plot of Reynolds number Vs Co.eff of Drag
From this plot, we can conclude that with the increase of Reynolds number, the coefficient of drag is decreasing. The Obtained plot is validated with Zdarvkovich's 1997 published article.
Plots for different Reynolds numbers
1. Re=10
2. Re= 100
(a) Steady
(b) Unsteady
3. Re=1000
4. Re=10000
5. Re= 100000
Preferred material:
Shim, Young Min, Rajnish Sharma, and Peter Richards. "Numerical study of the flow over a circular cylinder in the near wake at Reynolds number 3900." 39th AIAA Fluid Dynamics Conference. 2009.
Reference
[1] M. Zdravkovich, Flow Around Circular Cylinders, vol. 1, Oxford Science Publication, 1997.