Local transitions in flow phenomena through packed beds identified by MRI

Enhanced gas recovery with CO2 sequestration: The effect of medium heterogeneity on the dispersion of supercritical CO2–CH4

“…In contrast the increased velocity in the mobile fraction resulted in a significantly reduced diffusion film length for exchange between the mobile and immobile fractions manifesting in an increase in . This is consistent with the results of Johns et al (2000) in which detailed 3D Magnetic Resonance Imaging (MRI) velocity measurements were acquired for flow through unconsolidated porous media. Those results revealed that the stagnant portion of the fluid was relatively constant as flow rate was increased, whereas the velocity profile in the individual (mobile) pores increased and flattened, consistent with an increased value of .…”

Pore-Scale Flow Measurements at the Interface between a Sandy Layer and a Model Porous Medium: Application to Statistical Modeling of Contact Erosion

“…So, contact erosion is usually initiated in a Forchheimer flow regime where both viscous and inertial forces must be considered. Measurements of flow characteristics at pore-scale have been realized by Nuclear Magnetic Resonance methods (Lebon, 1996;Johns, 2000) and by Laser Doppler Velocimetry (Giese, 1998) or Particle Tracking Velocimetry in a refraction-index matched porous medium (Rashidi, 1996;Lachhab, 2008;Huang, 2008). Numerical simulations have also been carried out by Lattice Boltzmann method (Maier, 1999) and by direct resolution of Navier-Stokes equations (Magnico, 2003).…”

Measurements of Transitional and Turbulent Flow in a Randomly Packed Bed of Spheres with Particle Image Velocimetry

“…10. Also Moroni et al (2001), Johns et al (2000); Lebon et al (1996) reported a symmetric distribution for u y for low Re p . As Re p increases the maximum changes slightly toward the negative side and the curves becomes basically the same, self-similar, for 1170 ≤ Re p ≤ 3230.…”

“…Johns et al (2000) who studied porous media with MRI obtained a peak for the most probable u * x at Re of about 1. However for higher Re, e.g., Re = 4, their plots show a small plateau.…”