Applied fluid mechanics

Question

APPLIED FLUID MECHANICS:

2-D & 3-D Simulations of the flow around a circular cylinder normal to the flow direction using FLUENT.

Assume a cylinder of diameter D and length L each placed in a flow as shown in figure shown below. We are interested in finding out the flow the cylinder as the Reynolds number Re = ρU_oD/µ change. The wake behind a long cylinder (2-D) becomes unstable above low Reynolds numbers (Re > 50), resulting the appearance of large-scale periodic vortex patterns, such as the Karman street that typically forms at the Strouhal frequency (St = f_shedD/Uo) where fshed is the frequency of vortex shedding. In order to capture these phenomena you need to run the unsteady incompressible laminar viscous flow code of Fluent. The flow medium is air or water and each of you is required to:

1) Carry out 2-D simulations at various Re which will demonstrate the rich vortical patterns in the wake.

2) Carry out 3-D simulations for cylinders with L/D = 6, 3 & 1 at your assigned Re.