The effect of turbulence on mass and heat transfer rates of small inertial particles

TL;DR

This paper investigates how turbulence influences mass and heat transfer rates of small inertial particles, highlighting the roles of relative velocity and clustering effects, especially at high Damkohler numbers.

Contribution

It introduces models for relative velocity and clustering effects on transfer rates, enhancing simulation accuracy for turbulent particle-laden flows.

Findings

Relative velocity between fluid and particles affects transfer rates.

Clustering inhibits mass transfer at high Damkohler numbers.

A new model integrates clustering effects into particle simulations.

Abstract

The effect of turbulence on the mass and heat transfer between small heavy inertial particles (HIP) and an embedding fluid is studied. Two effects are identified. The first effect is due to the relative velocity between the fluid and the particles, and a model for the relative velocity is presented. The second effect is due to the clustering of particles, where the mass transfer rate is inhibited due to the rapid depletion of the consumed species inside the dense particle clusters. This last effect is relevant for large Damkohler numbers and it may totally control the mass transfer rate for Damkohler numbers larger than unity. A model that describes how this effect should be incorporated into existing particle simulation tools is presented.