On the interaction of turbulence with nucleation and growth in reaction crystallisation
OA Location
Author(s)
Tang, Hin Yan
Rigopoulos, Stelios
Papadakis, George
Type
Journal Article
Abstract
The objective of this work is to investigate the interaction of turbulence with the nonlinear processes of particle nucleation and growth that occur in reaction crystallisation, also known as precipitation. A validated methodology for coupling the population balance equation with direct numerical simulation of turbulent flows is employed for simulating an experiment conducted by Schwarzer <jats:italic>et al.</jats:italic> (<jats:italic>Chem. Engng Sci.</jats:italic>, vol. 61, no. 1, 2006, pp. 167–181), where barium sulphate nanoparticles are formed by mixing and reaction of barium chloride and sulphate acid in a T-mixer, with the spatial resolution resolved down to the Kolmogorov scale. A unity Schmidt number is assumed, since at present it is not possible to resolve the Batchelor scale for realistic Schmidt numbers (order of 1000 or more). The probability density function, filtered averages and spatial distribution of time and length scales are all examined in order to shed light on the interplay of turbulence and precipitation. Separate Damköhler numbers are defined for nucleation and growth and both are found to be close to unity, indicating that the process is neither mixing nor kinetics controlled. The nucleation length scales are also evaluated and compared with the Kolmogorov scale to show the importance of resolving nucleation bursts. In addition, zones of different rate-determining mechanisms are identified. The ultimate aim of precipitation is to obtain control over the product particle size distribution, and the present study elucidates the synergistic or competing roles of mixing, nucleation and growth on the process outcome and discusses the implications for modelling.
Date Issued
2022-08-10
Date Acceptance
2022-06-08
Citation
Journal of Fluid Mechanics, 2022, 944
ISSN
0022-1120
Publisher
Cambridge University Press (CUP)
Journal / Book Title
Journal of Fluid Mechanics
Volume
944
Copyright Statement
© The Author(s), 2022. Published by Cambridge University Press
License URL
Sponsor
The Leverhulme Trust
Identifier
https://www.cambridge.org/core/journals/journal-of-fluid-mechanics/article/on-the-interaction-of-turbulence-with-nucleation-and-growth-in-reaction-crystallisation/D6F9E2127B9F576DBC6EB681DECD9A1B
Grant Number
RPG-2018-101
Subjects
Fluids & Plasmas
01 Mathematical Sciences
09 Engineering
Publication Status
Published online
Article Number
A48
Date Publish Online
2022-07-05