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.

Effect of fluid flow on the fluctuations at the surface of an elastic medium

Abstract: The effect of a linear shear flow of a Newtonian fluid in the region 0

Indirect on-line determination of Newtonian fluid viscosity based on numerical flow simulations

Abstract: A new indirect method of determining the viscosity of a Newtonian fluid flowing in a tube with a geometrical singularity is proposed. Due to this singularity, the shape of the dimensionless velocity profiles is closely correlated with the Reynolds number of the flow. Newtonian fluid flows were simulated numerically with various Reynolds numbers. Based on the results of these calculations, an abacus was plotted showing the relationship between the dimensionless velocity and the dimensionless viscosity. On the other hand, dimensionless velocities were also obtained by measuring velocity profiles on a hydrodynamic bench with an ultrasonic Doppler velocimeter. These experimental values were plotted on the abacus and the viscosity of the actual fluid was thus determined. Comparisons were made with viscometer measurements in order to assess the accuracy of the method and its range of validity. This method is of great potential interest for application to industrial plans when it is necessary to know the viscosity of a fluid undergoing a transformation without interrupting the process by taking fluid samples.

Effect of Slip Condition on Couple Stress Fluid Flow in a Channel with Mild Stenosis in the Presence of Uniform Magnetic Field

Abstract: The steady flow of an incompressible couple stress fluid in a two dimensional uniform channel with stenosis under the influence of a magnetic field has been investigated. Assuming the stenosis to be mild, the flow equations have been analytically solved using the slip condition and expressions for the resistance to flow and wall shear stress have been derived. The effects of various parameters on these flow variables have been studied. It is found that the resistance to flow as well as the wall shear stress increase with the height of the stenosis and decrease with the couple stress and magnetic parameters. The effects of other parameters on resistance to flow and the wall shear stress have been considered.

A Dynamic Model of the Spine Using a Porous Elastic Material

Abstract: : A preliminary investigation of a two-phase solid-fluid continuum model to represent the spinal column subjected to dynamic loadings is presented The two-fold purpose of this investigation is (1) to examine a simple dynamic model that has a continuum representation and offers a capability to include the inertia and pressure effects of a fluid and (2) to use this model to study what effect the presence of a fluid has on the stresses in the solid material The model consists of a uniform straight porous elastic column containing a viscoelastic fluid and supporting a mass to represent the head Loading consists of a constant acceleration at the base of the column Two types of boundary conditions for the fluid at the upper end of the column are considered The problem is formulated in terms of two coupled partial differential equations with the displacements of the fluid and the solid material treated as unknowns (Author)

Thermohydrodynamic Analysis of Journal Bearings Lubricated by Non-Newtonian Fluids—Theory and Experiments

Abstract: Viscosity index improvers cause the lubricants to exhibit non-Newtonian flow behaviour and display shear thinning and normal stress differences. Shear thinning behaviour is studied by using a rotary shear viscometer. Owing to the non-availability of a rheogoniometer (for the measurement of normal stress differences), the first normal stress difference is calculated from the viscometric data using the Carreau viscosity function. The influence of the first normal stress difference on the hydrodynamic lubrication is analysed and shows that most of the commercial oils are inelasticoviscous in nature. Regression analysis shows that a large number of commercial lubricants follow the inelasticoviscous cubic law fluid model. Hence the cubic law fluid model is considered for the theoretical analysis.An experimental programme is developed to measure the effect of test parameters on the performance of a journal bearing lubricated with different types of non-Newtonian fluids. The experiments mainly include the measur...