Mechanism of Tubular Pinch Effect of Dilute Suspension in a Pipe Flow

TL;DR

This paper investigates the tubular pinch effect in dilute suspension flow within pipes, using the energy gradient method to explain particle migration towards a specific radial position at low Reynolds numbers.

Contribution

It applies the energy gradient method to elucidate the mechanism behind the tubular pinch effect in laminar suspension flow.

Findings

Particles migrate to r/R=0.58 at low Reynolds numbers.

The energy gradient method effectively explains the particle migration mechanism.

The study enhances understanding of particle distribution in laminar pipe flows.

Abstract

Experiments have shown that in dilute suspension flow at laminar state through a circular tube particles migrate towards a concentric annular region with a mean radius of about 0.6 of the tube radius. This phenomenon is well-known as the tubular pinch effect, which is still not fully understood. In this study, the energy gradient method is used to study this phenomenon. It is found that at low Reynolds number particles will move to the position of r/R=0.58. Based on the result, the mechanism of this phenomenon is well explained.