Theoretical investigation of effects of flow oscillations on ultrasound Doppler velocity measurements

Date

2012-02-01

Author

Koseli, Volkan
Uludağ, Yusuf

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Effects of flow oscillations on spectrum of Ultrasound Doppler Velocimetry (UDV) signals were investigated theoretically and numerically. A laminar pipe flow with a superimposed oscillating component was considered. Negative impact of oscillation on the ultrasound signal hence on the flow images was observed in the form of spreading of spectral ultrasound signal energy around mean component, leading to image artifacts. Both analytical and numerical results revealed the strong effect of a group of parameters including Doppler frequency, flow oscillation amplitude and frequency. Exceeding a particular value of the group, 1.45, resulted in artifacts in the flow images. Revealing the mechanisms involved in the deteriorations associated with the flow oscillations is potentially useful in UDV studies involving random flow fluctuations such as turbulence.

Subject Keywords

Acoustics and Ultrasonics

URI

https://hdl.handle.net/11511/37281

Journal

ULTRASONICS

DOI

https://doi.org/10.1016/j.ultras.2011.08.009

Collections

Department of Chemical Engineering, Article

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Citation Formats

V. Koseli and Y. Uludağ, “Theoretical investigation of effects of flow oscillations on ultrasound Doppler velocity measurements,” ULTRASONICS, pp. 244–254, 2012, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/37281.