What about the Break Frequency?
Have analyzed a number of studies that have looked at the technique of phonoangiography.
Available data seems to cast some doubt on the original hypothesis of Lees and Dewey.
- Spectra of arterial bruits is very dissimilar to the “turbulent” spectrum of Lees & Dewey.
- In particular a clear peak is usually distinguishable
- fo d /U is not a constant but is a strong function of Reynolds number.
- Break frequency is in fact the shear layer frequency ?????