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.

Dissipative instability of fluid flows with piecewise linear velocity profiles

Abstract: The viscous dissipative instability of two flows with continuous spectrum of neutrally-stable perturbations in the absence of dissipation is investigated. Ranges of wave numbers in which viscosity leads to flow destabilization are determined for a shear discontinuity in a smoothly-stratified fluid. A shear flow with a velocity in the transition layer that depends linearly on the coordinate has a continuum of neutral modes even in the case of an unstratified fluid. When viscosity is present in one of the layers with constant velocity, one of the branches of the spectrum becomes unstable. When the viscosity is the same above and below the shear layer, dissipation only leads to the damping of the perturbations.

MHD Flow of Shear-Thinning Fluid over a Rotating Disk with Heat Transfer

Abstract: This paper studied the Magneto hydrodynamic (MHD) flow and heat transfer of an electrically conducting non-Newtonian fluid over a rotating disk in the presence of a uniform magnetic field The steady, laminar and axial-symmetric flow is driven solely by the rotating disk, and the incompressible fluid obeys the inelastic Ostwald de-Waele power-law model The governing differential equations were reduced to a set of ordinary differential equations by utilizing the generalized Karman similarity transformation The nonlinear two-point boundary value problem is solved by multi-shooting method Numerical results show that the magnetic parameter and the power-law index have significant effects on the swirling flow and heat transfer

Effect of viscoelastic polymer on residual oil

Abstract: Based on the types of residual oil in pore media after water flooding and the viscoelasticity of polymer fluid in reservoir pore, undulating tube model which has the contraction - expansion cyclical process and upper-convected Maxwell model which is generally applied to numerical calculation of viscoelastic fluid areselected. The mathematics model made up of continuity equation, equation of motion,UCM constitutive equation, stream function, vorticity equation as well as the boundary conditions are established. By effective numerical calculation, the mechanism of improving oil displacement efficiency of polymer fluid through mechanical analysis and theories analysis is:(1) the rolling action on oil film by first normal stress and shear stress from viscoelastic polymer fluid is greater than the one by shear stress from Newtonian fluid with same viscosity, residual oil film can flow partly;(2) comparing polymer fluid with Newtonian fluid, the same stream line is not in the same position, and the swept volume of viscoelastic polymer fluid is larger than Newtonian fluid with same viscosity.