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Updated: Jan 8, 2026

Visualization of Flow Field Around a Vibrating Pipeline Within an Equilibrium Scour Hole

Visualization of Flow Field Around a Vibrating Pipeline Within an Equilibrium Scour Hole

Published on: August 26, 2019

多孔質媒体中の流速測定：定常状態自由歳差運動を用いたブロッホ・トレィ方程式の解析解と流れ

Mohammad Sadegh Zamiri¹, Naser Ansaribaranghar¹, Benedict Newling¹

¹UNB MRI Centre, Department of Physics, University of New Brunswick, Fredericton, New Brunswick E3B 5A3, Canada.

The Journal of chemical physics

|December 22, 2025

Abstract:

In this study, fluid velocity is measured in a porous medium using a magnetic resonance steady state free precession (SSFP) technique. As shown theoretically and experimentally in this study, the SSFP measurement under steady flow conditions produces a periodic steady state magnetization with a strong flow sensitivity. The Bloch-Torrey equations were solved analytically using a Fourier series to predict the distortion of the steady state response due to flow. The analytical solution accurately describes the measured steady state longitudinal magnetization and transverse magnetization phase to permit the determination of the fluid velocity in a Bentheimer sandstone core plug non-invasively.

キーワード:

多孔質媒体流速測定磁気共鳴定常状態自由歳差運動ブロッホ・トレィ方程式流れ砂岩

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