Mixing intensification under turbulent conditions in a high pressure microreactor
ERRIGUIBLE, Arnaud
Institut de Mécanique et d'Ingénierie de Bordeaux [I2M]
Institut de Chimie de la Matière Condensée de Bordeaux [ICMCB]
Institut de Mécanique et d'Ingénierie de Bordeaux [I2M]
Institut de Chimie de la Matière Condensée de Bordeaux [ICMCB]
ERRIGUIBLE, Arnaud
Institut de Mécanique et d'Ingénierie de Bordeaux [I2M]
Institut de Chimie de la Matière Condensée de Bordeaux [ICMCB]
< Reduce
Institut de Mécanique et d'Ingénierie de Bordeaux [I2M]
Institut de Chimie de la Matière Condensée de Bordeaux [ICMCB]
Language
en
Article de revue
This item was published in
Chemical Engineering Journal. 2019-09, vol. 382, p. 122859 (12 p.)
Elsevier
English Abstract
The turbulent mixing of two miscible fluids is investigated in a high pressure (HP) coflow microreactor operated at 100 bar. Ethanol and CO2 are selected as model solvents to mimic the final targeted application, i.e.: a ...Read more >
The turbulent mixing of two miscible fluids is investigated in a high pressure (HP) coflow microreactor operated at 100 bar. Ethanol and CO2 are selected as model solvents to mimic the final targeted application, i.e.: a supercritical antisolvent process at microscale (SAS). We first demonstrate experimentally that turbulent mixing can be reached in a microchannel using HP microfluidics. A computational fluid dynamic (CFD) model, performed using direct numerical simulation (DNS) down to the Kolmogorov scale has been applied for the turbulent mixing simulations. The effects of the main operating parameters on the final mixing efficiency have been studied, namely: the temperature, the fluid flowrates, the microchannel dimensions and the capillary inner and outer diameters. According to a predefined intensity of segregation, the characteristic mixing times are determined and used for determining mixing efficiency. The ratio of the total mixing time to the diffusion time depends on the ratio of the kinetic energies (the outer fluid to the inner one). The obtained micromixing times have been related to the turbulent energy dissipation rate ∊, calculated directly from the velocity fluctuations. The mixing intensification is obtained with much lower characteristic mixing times in the microreactor (one order of magnitude) than previously reported. This fundamental study is an indispensable guidance for several processes, including the SAS applications.Read less <
English Keywords
Micromixing
Supercritical fluid
Microfluidics
Mixing intensification
ANR Project
Synthèse de nanocristaux organiques fluorescents en milieu fluide supercritique: une approche numérique et expérimentale complémentaire - ANR-17-CE07-0029
Origin
Hal imported