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James88 March 7, 2012 19:10

Isolating a model area?
Hey everyone,

I am not sure how to explain what I need... Basically, I am trying to measure the vortex shedding frequency given from finite cylinders at varying length/diameter ratios. I understand from previous research that the Strouhal number varys along the length of the cylinder.
In my 2D simulations, I obtained the frequency by creating a lift coefficient report, and inverting the time period, which ended up giving me the expected value.
However, I would like to measure the shedding frequency for different areas of the cylinder... say, the centre, and halfway from the centre to the finite end.
I am unsure how to go about this. My first though would be to use a function (IF IT EXISTS!) that isolates an area of the cylinder, so that could be the part selected for my lift report... Does anything like this exist?

If any of you know any other ways to go about this, I would value your input!
Also, I saw that there is a Strouhal number Fourier transform function in the data set tools. How would I go about using this?

Many thanks to you all! :)


abdul099 March 12, 2012 04:17

Just split up the boundary. I would create a block to split and do an intersect in surface repair, and afterwards a split by feature curve. You will get different boundaries which you can choose separately for your reports.
You need to remesh after the split, since you need a well defined border between your different boundaries. That's why I would do it on the parts level.

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