I am working on obtaining the vortex shedding frequencies behind a 2D square using CFD. Time-varying data is being extracted from a specific cell behind the square. I've written a little python script which performs FFT analysis on the signal and spits out the dominant peak frequency.
Because the shedding frequencies are so low (0.1 - 0.2 Hz) I added a zero-padding routine as well as a quadratic interpolator in order to have accuracy to several digits. My background is in fluid mechanics, not signal analysis. So my question is the following:
Would it be more beneficial to simply take my input signal (of say, 200 seconds of data) and repeat it several times (therefore increasing the length of time and subsequently the frequency resolution) or to keep the zero-padding technique?
Would the former method be much more computationally intensive? FYI, the signal is nearly sinusoidal.