Topic
Herschel–Bulkley fluid
About: Herschel–Bulkley fluid is a research topic. Over the lifetime, 1946 publications have been published within this topic receiving 49318 citations.
Papers published on a yearly basis
Papers
More filters
19 Dec 2022
TL;DR: In this article , the authors studied the blocking force of the steady-state flow of a Herschel-Bulkley fluid in a bounded domain and established the existence of blocking force.
Abstract: The paper is devoted to the study of the blocking force of Herschel-Bulkley fluid in the case of steady-state flow. To this aim, we consider a mathematical model which describes the steady-state flow of a Herschel-Bulkley fluid in a bounded domain. We give the mathematical formulation of the blockage phenomenon and we establish the existence of blocking force. We also focus on behaviour of the flow with respect to the blocking force.
TL;DR: In this article , the authors explored the self-similarity of coupled gravity currents with axisymmetric spreading of a power-law fluid on top of a Newtonian fluid, where each fluid volume grows in time.
Abstract: The motion of glaciers over their bedrock or drops of fluid along a solid surface can become unstable when these substrates are lubricated. Previous studies modelled such systems as coupled gravity currents (GCs), consisting of one fluid that lubricates the flow of another fluid, and having two propagating fronts. When both fluids are Newtonian and discharged at constant flux, global similarity solutions were found. However, when the top fluid is strain-rate softening, experiments have shown that each fluid front evolved with a different exponent. Here, we explore theoretically and numerically such lubricated GCs consisting of axisymmetric spreading of a power-law fluid on top of a Newtonian fluid, where each fluid volume grows in time like $t^{\alpha }$ . We find that the structure imposed by the non-Newtonian flow precludes general self-similarity, unlike purely Newtonian GCs. Consequently, we identify outstripping solutions in which the inner fluid front outstrips the outer fluid front. Despite the absence of a general global similarity solution, we find similarity solutions in several asymptotic limits. These include the purely Newtonian limit for any $\alpha$ , the case of $\alpha =5$ for a general power-law fluid, asymptotic limits in the viscosity ratio, and in the vicinity of the fluid fronts. Many of our theoretical predictions are found to be consistent with recent laboratory experiments. Discrepancies suggest the presence of hydrofracturing or wall slip near the fronts, and potentially, a progressive significance of extensional stresses as front outstripping is approached.
TL;DR: In this article, the problem of the flow of a viscous incompressible fluid in a tube of finite length with valves at the ends is solved numerically with allowance for gravity and elastic wall properties that vary periodically with time.
Abstract: The problem of the flow of a viscous incompressible fluid in a tube of finite length with valves at the ends is solved numerically with allowance for gravity and elastic wall properties that vary periodically with time.
Journal Article•
TL;DR: In this paper, the effects of a magnetic field on unsteady flow of a viscoelastic fluid with the fractional Burgers' model between two parallel plates are investigated.
Abstract: The aim of this paper is to study the effects of a magnetic field on unsteady flow of a viscoelastic fluid with the fractional Burgers' model between two parallel plates .The fractional calculus approach is introduced to establish the constitutive relationship of the viscoelastic fluid. Closed form solutions fo r velocity and shear stress are obtained by using the finite Fourier sine transform and discrete Laplace transform of the sequential fractional derivatives. For ==1 the solution that are obtained are going corresponding to ordinary Oldroyd -B fluid. Finally, the effect of the material parameters on the velocity profile and shear stress profile spotlighted by means of the graphical illustrations.
01 Dec 2010
TL;DR: In this paper, the physicochemical properties of three grades of aromatic extracts were initially studied and the rheological behavior (viscosity, shear stress and shear rate) of individual aromatic extracts, and the obtained greases from those extracts at different temperatures were also illustrated.
Abstract: Utility of aromatic extracts as fluid for preparation of calcium complex greases was investigated. The physicochemical properties of three grades of these extracts were initially studied. The rheological behavior (viscosity, shear stress and shear rate) of the individual aromatic extracts, and the obtained greases from those extracts at different temperatures were also illustrated. The rheological properties of both aromatic extracts and all lubricating greases were properly fit with the mathematical model of Herschel-Bulkley. Moreover, the flow behavior of the aromatic extracts as well as the corresponding lubricating greases was non-Newtonian. The study exhibited promising results concerning the thermal, mechanical and rheological properties for the prepared greases. Hence, in this work the by-product aromatic extracts act as a good alternative fluid for calcium complex lubricating greases.