Showing papers on "Herschel–Bulkley fluid published in 1977"
TL;DR: The effective elastic moduli of a fluid-saturated solid containing thin cracks depend on the degree of interconnection between the cracks as mentioned in this paper, which can be estimated from the crack geometry or permeability.
Abstract: The effective elastic moduli of a fluid-saturated solid containing thin cracks depend on the degree of interconnection between the cracks. Three separate regimes may be identified: (1) dry (drained), in which fluid in cracks can flow out of bulk regions of compression, (2) saturated isobaric, in which fluid may flow from one crack to another but no bulk flow takes place, and (3) saturated isolated, in which there is no communication of fluid between cracks. Transitions between these cases involve fluid flow, resulting in dissipation of energy. Relaxation of shear stresses in viscous fluid inclusions also results in dissipation. Viscoelastic moduli are derived, by using a self-consistent approximation, that describe the complete range of behavior. There are two characteristic frequencies near which dissipation is largest and the moduli change rapidly with frequency. The first corresponds to fluid flow between cracks, and its value can be estimated from the crack geometry or permeability. The second corresponds to the relaxation of shear stress in an isolated viscous fluid inclusion; its value may also be estimated. Variations of crack geometry result in a distribution of characteristic frequencies and cause Q to be relatively constant over many decades of frequency. Fluid flow between cracks accounts for attenuation of seismic waves in water-saturated rocks and attenuation observed in laboratory measurements on water-saturated rocks and partially molten aggregates. Attenuation in a partially molten upper mantle is probably due to fluid flow between cracks, although grain boundary relaxation in an unmelted upper mantle could also account for the seismic low-velocity zone. Grain boundary relaxation in the mantle may cause the long-term shear modulus to be around 20% less than that measured from seismic observations.
835 citations
TL;DR: The Gauss-Hertz principle when coupled with an accessory condition based on the assumption that fluid pressure is always positive is used to derive both well known flows such as Couette and Poiseuille, and the velocity and force fields of a magnetically confined plasma as discussed by the authors.
Abstract: The Gauss–Hertz principle when coupled with an accessory condition based on the assumption that fluid pressure is always positive is used to derive both well known flows such as Couette and Poiseuille, and the velocity and force fields of a magnetically confined plasma.
2 citations
01 May 1977
TL;DR: In this paper, an approximate solution for the flow past an impulsively started infinite porous plane wall in an elastico-viscous fluid is obtained for the velocity and shearing stress.
Abstract: Approximate solution for the flow past an impulsively started infinite porous plane wall in an elastico-viscous fluid is obtained for the velocity and shearing stress. The roles of elasticity of the liquid and the suction on the velocity and the shearing stress have been studied.
1 citations
TL;DR: In this paper, a constitutive equation for a fluid that contains string-like particles which can support strain in flow direction is given, and the authors show that it can be expressed as follows:
Abstract: We give a constitutive equation for a fluid that contains string-like particles which can support strain in flow direction.
1 citations