Theoretical and Experimental Investigation of Effects of Flow Fluctuations on UDV Signals
نویسندگان
چکیده
Effects of oscillating flows on the frequency spectrum of back-sampled pulsed ultrasound signals (PUS) are investigated both experimentally and theoretically. Simulation results revealed that while coherent component of velocity is encoded in the phase of the PUS, oscillating component is observed in terms of the amplitude and variance of the signal. The attenuation and variance increase on PUS spectrum in turbulent flow regime was also observed experimentally in measurements on a pipe flow system by means of DOP2125. Obtained PUS spectrums were closely related to the probability density function (pdf) of velocity at measurement point. The results indicate that ultrasound Doppler method can also be employed to determine turbulent flow characteristics such as time-averaged velocity, turbulence intensity and kinetic energy distributions in a pipe flow.
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