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.

On the Study of Magneto-Hydrodynamic Non-Newtonian Fluid Flow throughout Curvilinear Channel with Corrugated Walls

Abstract: This article aims to numerically investigate the flow pattern for Newtonian and power law non-Newtonian fluid in a semi-half circular channel with corrugated walls under the influence of a magnetic field. The results indicate that, presence of a magnetic field affects the flow field in several aspects, especially in the vortex creation and dissipation. In addition, the analysis is carried out for different Reynolds numbers to ascertain the influence of magnetic field on each flow regime. Eventually, the analysis is carried out for a range of power indices including pseudo plastic (shear-thinning) to dilatants (shear-thickening) fluids. The results show that by increasing the power-index, the vortices begin to form and grow gradually so that in the shear-thickening fluid an extra vortex is formed and created nearby the corrugated part of the channel.

Determination of rheological constants of an elastico-viscous fluid by kinematical analysis of oscillatory motions

Abstract: This paper contains experimental and theoretical work on a rotatory oscillatory flow of an elastico-viscous fluid. Assuming a linear constitutive equation, the motion of the fluid contained in a spherical or circular cylindrical vessel is computed. In particular, the limited height of the cylinder is taken into account for the boundary conditions. The solutions yield the velocities of the fluid particles as functions of the constitutive equation parameters, everywhere in the flow field. The experimental study is essentially based upon quantitative vizualisation techniques with solid particles: the amplitude and phase of the displacements of the tracers suspended in the fluid are obtained from an analysis of the photographs. Using the above-mentioned theoretical results we deduce the measurement of characteristic coefficients and functions of the materials tested. An experimental investigation of moderately concentrated aqueous solutions of polyethylene oxide is carried out.

Analysis of effect of time on the flow rate of an incompressible fluid of second order type when the bounding surface is subjected to sinusoidal disturbances

Abstract: In this paper the effect of time on the flow rate when the bounding surface is subjected to sinusoidal disturbances has been studied. The fluid under the consideration is of second order. When the angle of inclination of the fluid bed is increased, the flow rate is found to be periodic in its nature over a period of time. Further, it is noticed that, for constant angle of inclination, as the visco elasticity of the fluid is increased, still the periodic nature of flow rate is preserved. An interesting phenomenon that can be attributed for the above is due to the strong intra molecular forces in the fluid medium. Further, when the time parameter is constant and as the porosity of the fluid bed is increased, for a constant time, a decreasing trend in the flow rate is noticed. However, the graphical and analytical results illustrate an interesting phenomenon. Also, for a constant visco elasticity of the fluid and for a fixed angle of inclination and porosity, as the frequency of excitation of the fluid bed is increases, the flow rate is found to be sinusoidal. And at times, the back flow is also noticed and this is due to strong intra molecular forces in the fluid medium. Further, as the frequency of excitation increases, in general the flow rate increases. All such observations are illustrated graphically.

Numerical simulation of generalized second-grade fluids using a 1D hierarchical model

Abstract: We consider the flow of a non-Newtonian incompressible second-grade fluid in an uniform rectilinear pipe and generalize it by introducing a shear-dependent viscosity function of power law type. The full 3D set of equations is reduced to a one-dimensional problem involving only time and one spatial variable. This is done using a director theory for fluid dynamics, also called Cosserat theory. An axisymmetric unsteady relationship between mean pressure gradient and volume flow rate over a finite section of the pipe and the corresponding equation to the wall shear stress are derived from this theory.