Step 6: Analyze Results
Calculate Strouhal Number
Lift convergence plot can be used to compute the correct value of Strouhal number. Non-dimensionalize the problem and Sr = f*D/U = 0.0846 * 2 = 0.169. The results matches fairly well with the value 0.183 as reported by Williamson
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title | Calculating Shedding Frequency |
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To accurately calculate the shedding frequency, open the cl-history file (saved previously in the same location where the original mesh was read) and plot the data using excel for better data representation and graphing option. Take an average of 10 shedding cycles (e.g 10 CL peak).
{latex}
\large
$$
{\rm{Period}} = {{T_2 - T_1} \over {10}}
$$
{latex}
{latex}
\large
$$
{\rm{f}} = {{1} \over {Period}}$$
{latex}
{latex}
\large
$$
{\rm{Sr}} = {fD \over U}
$$
{latex}
An example of Lift Convergence Plot plotted using excel is shown below:
{newwindow:Higher Resolution Image}https://confluence.cornell.edu/download/attachments/107011456/Excel%20Lift%20convergence.jpg{newwindow}
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Display Pressure Contours
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