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
TL;DR: The hydrodynamic theory of particle movement in non-Newtonian fluids is addressed from a rheological perspective in this article, where the shear rate due to particle-to-fluid relative movement, the particle Reynolds number, and a general form of Stokes' equation for non-newtonian fluid are proposed.
50 citations
TL;DR: A fluid dynamics model is constructed that can describe basic features of the dilatant fluid such as the stress-shear rate curve that represents discontinuous severe shear thickening, hysteresis upon changing shear rate, and instantaneous hardening upon external impact.
Abstract: A dense mixture of granules and liquid often shows a severe shear thickening and is called a dilatant fluid. We construct a fluid dynamics model for the dilatant fluid by introducing a phenomenological state variable for a local state of dispersed particles. With simple assumptions for an equation of the state variable, we demonstrate that the model can describe basic features of the dilatant fluid such as the stress-shear rate curve that represents discontinuous severe shear thickening, hysteresis upon changing shear rate, and instantaneous hardening upon external impact. An analysis of the model reveals that the shear thickening fluid shows an instability in a shear flow for some regime and exhibits the shear thickening oscillation (i.e., the oscillatory shear flow alternating between the thickened and the relaxed states). The results of numerical simulations are presented for one- and two-dimensional systems.
50 citations
TL;DR: In this article, a new constitutive equation is proposed for viscoelastic fluids based on the time derivatives of the left Cauchy-Green strain tensor and is thus believed to characterize a new material.
Abstract: In this paper a new constitutive equation is proposed for viscoelastic fluids. It is based on the time derivatives of the left Cauchy-Green strain tensor and is thus believed to characterize a new material. From this constitutive equation, a second-order approximation is derived and it is shown that this second order fluid has a bounded and unique solution to the initial value problem of cessation of steady shear flow. This stability is in direct contrast with the presently well known second order models. Further, the natural time of the fluid is positive, making the theory consistent with the intuitive notion that phenomena in dissipative materials should depend on the past rather than the future. Finally, a test is proposed to distinguish the present second-order model from the earlier version.
50 citations
TL;DR: In this article, the relative importance of inertial, viscous and yield stress effects on the filling profile of a 2D cavity was examined using PAM-CAST/SIMULOR, which was modified by introducing a regularized Bingham fluid constitutive relation.
Abstract: The present study concentrates on Bingham fluid filling of a 2-D cavity and examines the relative importance of inertial, viscous and yield stress effects on the filling profile. The results presented are obtained using PAM-CAST/SIMULOR, which was modified by introducing a regularized Bingham fluid constitutive relation. The results identify five different flow patterns: “mound,” “disk,” “shell,” “bubble,” and a “transition flow” between that of mound and bubble patterns. A complete map of the flow patterns as a function of the Reynolds and Bingham numbers is also presented and discussed using dimensional and physical arguments within a simplified theoretical framework.
49 citations
TL;DR: In this article, a particle-fluid model was developed for predicting the relationship between the shear stress and shear strain rate of highly flowable mortars, where a two-phase material, containing a fluid matrix (cement paste) and a group of well-graded, non-cohesive, and rigid particles (fine aggregate) that are uniformly distributed in the matrix, was considered.
Abstract: A particle–fluid model is developed for predicting the relationship between the shear stress and shear strain rate of highly flowable mortars. In this model, mortars are considered as a two-phase material, containing a fluid matrix (cement paste) and a group of well-graded, non-cohesive, and rigid particles (fine aggregate) that are uniformly distributed in the matrix. The mortar shear stress is assumed to be the sum of the shear stresses resulting from the paste flow, the aggregate particle movement, and the interaction between the cement paste and aggregate. The shear stress resulting from the paste flow is assessed using constitutive equations. The shear stress resulting from the aggregate particle movement is evaluated based on the probability and mechanical concepts of aggregate particle collision. The shear stress resulting from the interaction between the paste and aggregate is considered as the normal stress that the moving aggregate particles apply onto the cement paste. The shear rate of the mortar is obtained from the rheological definition of viscosity. Using this model, the effects of mortar mixture properties (such as aggregate size, volume, gradation, and friction as well as paste viscosity and yield stress) on mortar rheology are studied.
49 citations