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 Unsteady Flow Past a Cylinder - Panel Unsteady Flow Past a Cylinder - Panel

# Unsteady Flow Past a Cylinder

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Compared to the steady case, the unsteady case includes an additional time-derivative term in the Navier-Stokes equations:

{latex}
Wiki Markup
Latex
\begin{eqnarray}
\frac{\partial \vec{u}}{\partial t} + \rho (\vec{u}\cdot \triangledown)\vec{u} = -\triangledown p + \mu \triangledown^{2} \vec{u}
\end{eqnarray}
{latex}

The methods implemented by FLUENT to solve a time dependent system are very similar to those used in a steady-state case.  In this case, the domain and boundary conditions will be the same as the Steady Flow Past a Cylinder.  However, because this is a transient system, initial conditions at t=0 are required.  To solve the system, we need to input the desired time range and time step into FLUENT.  The program will then compute a solution for the first time step, iterating until convergence or a limit of iterations is reached, then will proceed to the next time step, "marching" through time until the end time is reached.

Go to Step 1: Pre-Analysis & Start-Up

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