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In flows with small
Bagnold numbers (Ba < 40), viscous fluid stresses dominate grain collision stresses, and the flow is said to be in the "macro-viscous" regime. Grain collision stresses dominate at large Bagnold number (Ba > 450), which is known as the "grain-inertia" regime. A transitional
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Hunt, M. L.; Zenit, R.; Campbell, C. S.; Brennen, C.E. (2002). "Revisiting the 1954 suspension experiments of R. A. Bagnold".
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Bagnold, R. A. (1954). "Experiments on a
Gravity-Free Dispersion of Large Solid Spheres in a Newtonian Fluid under Shear".
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119:{\displaystyle \mathrm {Ba} ={\frac {\rho d^{2}\lambda ^{1/2}{\dot {\gamma }}}{\mu }}}
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518:Granular Material Flows at N.A.S.A
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43:The Bagnold number is defined by
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196:{\displaystyle {\dot {\gamma }}}
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376:{\displaystyle \phi _{0}}
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244:{\displaystyle \lambda }
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864:Weissenberg
470:(1): 1–24.
884:Categories
784:Richardson
565:Archimedes
407:References
205:shear rate
869:Womersley
760:turbulent
740:Ohnesorge
725:Marangoni
690:Iribarren
615:Damköhler
600:Capillary
480:CiteSeerX
365:ϕ
344:ϕ
314:−
295:ϕ
281:ϕ
262:λ
239:λ
215:μ
188:˙
185:γ
138:ρ
112:μ
105:˙
102:γ
82:λ
68:ρ
844:Suratman
834:Strouhal
814:Sherwood
777:magnetic
772:Reynolds
767:Rayleigh
755:magnetic
595:Brinkman
449:98030586
395:See also
30:granular
26:stresses
824:Stanton
819:Shields
809:Scruton
804:Schmidt
750:Prandtl
735:Nusselt
710:Laplace
705:Knudsen
695:Kapitza
680:Görtler
675:Grashof
665:Galilei
630:Deborah
575:Bagnold
502:9416685
472:Bibcode
429:Bibcode
227:is the
203:is the
152:density
854:Ursell
849:Taylor
839:Stuart
829:Stokes
794:Rossby
789:Roshko
745:PĂ©clet
730:Morton
670:Graetz
660:Froude
650:Eötvös
640:Eckert
635:Dukhin
605:Cauchy
570:Atwood
500:
482:
447:
336:where
130:where
859:Weber
799:Rouse
715:Lewis
685:Hagen
655:Euler
645:Ekman
620:Darcy
580:Bejan
498:S2CID
445:S2CID
28:in a
720:Mach
625:Dean
590:Bond
585:Biot
207:and
16:The
490:doi
468:452
437:doi
425:225
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40:.
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22:Ba
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265:=
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62:=
58:a
55:B
20:(
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