The use of micro-electrodes in the study of the flow regimes in a packed bed reactor with single phase liquid flow

Latifi, M.A.; Midoux, N.; Storck, A.; Gence, J. N.

doi:10.1016/0009-2509(89)85194-2

Cited by 82 publications

(32 citation statements)

References 7 publications

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“…However, flow visualization studies in porous media showed that turbulent flow occurs at much higher particle Reynold numbers than the critical particle Reynold numbers of 1-15 for the onset of nonlinear flow (e.g., Chauveteau and Thirriot 1967;Dybbs and Edwards 1984;Seguin et al 1998). Critical particle Reynolds number of 300-533 was determined for the onset of the turbulent flow regime using a uniform spheres packing with particle diameters ranging from 0.5 to 8 cm, respectively (Jolls and Hanratty 1966;Latifi et al 1989;Rode et al 1994;Seguin et al 1998), as well as for cylindrical or plate arrangements (Dybbs and Edwards 1984). Hence, a nonlinear laminar flow regime should be considered before fully turbulent flow develops in porous medium.…”

Section: Nonlinear Laminar Flow and Fully Turbulent Flow In Porous Mediamentioning

confidence: 99%

The Effect of Grain Size Distribution on Nonlinear Flow Behavior in Sandy Porous Media

et al. 2017

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The current study provides new experimental data on nonlinear flow behavior in various uniformly graded granular materials (20 samples) ranging from medium sands (d 50 > 0.39 mm) to gravel (d 50 = 6.3 mm). Generally, theoretical equations relate the Forchheimer parameters a and b to the porosity, as well as the characteristic pore length, which is assumed to be the median grain size (d 50 ) of the porous medium. However, numerical and experimental studies show that flow resistance in porous media is largely determined by the geometry of the pore structure. In this study, the effect of the grain size distribution was analyzed using subangular-subrounded sands and approximately equal compaction grades. We have used a reference dataset of 11 uniformly graded filter sands. Mixtures of filter sands were used to obtain a slightly more well-graded composite sand (increased C u values by a factor of 1.19 up to 2.32) with respect to its associated reference sand at equal median grain size (d 50 ) and porosity. For all composite sands, the observed flow resistance was higher than in the corresponding reference sand at equal d 50 , resulting in increased a coefficients by factors up to 1.68, as well as increased b coefficients by factors up to 1.44. A modified Ergun relationship with Ergun constants of 139.1 for A and 2.2 for B, as well as the use of d m − σ as characteristic pore length predicted the coefficients a and b accurately.

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Section: Nonlinear Laminar Flow and Fully Turbulent Flow In Porous Mediamentioning

confidence: 99%

The Effect of Grain Size Distribution on Nonlinear Flow Behavior in Sandy Porous Media

et al. 2017

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“…The occurrence of transition to turbulence is a complex function of size and shape of spacers and packing characteristics. Previous studies on packed beds [20][21][22][23] indicate that transition occurs in the Reynolds number range of 300-400 (based on particle diameter). Unfortunately, there are no such reported studies on the transition to turbulence in spacer filled channels.…”

Section: Transition To Turbulence In Spacer Filled Channelsmentioning

confidence: 99%

Fluid dynamics of spacer filled rectangular and curvilinear channels

Ranade

Kumar

2006

Journal of Membrane Science

126

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“…In fact, the existence of microscale turbulence in porous media has been detected Ž by several experiments by pointwise probes Jolls and Han-. ratty, 1966;Latifi et al, 1989 . For the macroscopic flow modeling in packed beds, however, the contribution of the Reynolds stress term to the fluid momentum equation is not Ž .…”

Section: Significance Of Terms In the Momentum Balancementioning

confidence: 99%