Taylor-Couette flow of hard-sphere suspensions: Overview of current understanding

TL;DR

This paper reviews experimental, theoretical, and computational studies on Taylor-Couette flow of neutrally buoyant suspensions, highlighting how finite-sized particles influence flow transitions, structures, and migration, with implications for modeling and understanding inertial particle-laden flows.

Contribution

It provides a comprehensive overview of current research on particle effects in Taylor-Couette flow, emphasizing flow transitions, structures, and modeling challenges.

Findings

Particles cause deviations from Newtonian behavior.

Flow transition Reynolds numbers shift with particle properties.

Particle migration and hysteresis affect flow dynamics.

Abstract

Although inertial particle-laden flows occur in a wide range of industrial and natural processes, there is both a lack of fundamental understanding of these flows and continuum-level governing equations needed to predict transport and particle distribution. Towards this effort, the Taylor-Couette flow (TCF) system has been used recently to study the flow behavior of particle-laden fluids under inertia. This article provides an overview of experimental, theoretical, and computational work related to the TCF of neutrally buoyant non-Brownian suspensions, with an emphasis on the effect of finite-sized particles on the series of flow transitions and flow structures. Particles, depending on their size and concentration, cause several significant deviations from Newtonian fluid behavior, including shifting the Reynolds number corresponding to transitions in flow structure and changing the possible structures present in the flow. Furthermore, particles may also migrate depending on the flow structure, leading to hysteretic effects that further complicate the flow behavior. The current state of theoretical and computational modeling efforts to describe the experimental observations is discussed, and suggestions for potential future directions to improve the fundamental understanding of inertial particle-laden flows are provided.