Data from a low pressure air test facility are used to quantify the influence of the acoustic field in the main line on side branch\r\nresonance behavior. The main line of diameter D = 7.6 cm may accumulate acoustic energy broadcast from a resonating branch\r\nof diameter d = 1.9 cm (d/D = 0.25). The side branch resonance amplitude is a strong function of branch position along the main\r\nline with the normalized pressure rising to 1.2 in the most favorable branch positions with Strouhal number near 0.3. Large time\r\nvariation of the side branch andmain line resonance amplitude is apparent formost branch positions. Amoving window is used on\r\nthe time history to collect an array of power spectral densities (PSDs). Peak amplitude values from the PSD array are represented\r\nin a probability density function (PDF) that provides a repeatable characterization of data from the system.
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