Design Automation and Optimization of Micro Cross-Junctions for Droplet Generation Using CFD and Machine Learning Approaches

Article Preview

Abstract:

This work numerically studies the water-in-oil (W/O) droplet formation inside a flow focusing on the micro junction formed by rectangular channels with dimensions of 390 × 190 μm2 using OpenFoam. An automatic algorithm was developed to assess the effect of key parameters such as water viscosity, restriction ratio and water mass flow rate ratio on the droplet size. A total of 96 simulations, with different parameter combinations, were conducted to train a Machine Learning (ML) algorithm capable of predicting the droplet dimensions based on the key parameters mentioned. The ML algorithm was also compared to a Newtonian-based optimization method, where the geometry is iteratively adjusted to produce droplets of a fixed size. Results reveal that both methods appear valid in the prediction of droplet dimensions.

You might also be interested in these eBooks

Info:

Periodical:

Pages:

67-76

Citation:

Online since:

December 2025

Export:

Price:

Permissions CCC:

Permissions PLS:

Сopyright:

© 2025 Trans Tech Publications Ltd. All Rights Reserved

Share:

Citation:

* - Corresponding Author

[1] S. Gimondi, H. Ferreira, R.L. Reis, N.M. Neves, Microfluidic devices: a tool for nanoparticle synthesis and performance evaluation. ACS Nano. 17 (2023) 14205–14228.

DOI: 10.1021/acsnano.3c01117

Google Scholar

[2] C. Qi, T. Zhou, X. Wu, K. Liu, L. Li, Z. Liu, et al., Micro-nano-fabrication of green functional materials by multiphase microfluidics for environmental and energy applications. Green Energy Environ. (2023).

DOI: 10.1016/j.gee.2023.05.012

Google Scholar

[3] Y. Zhang, Y. Song, Z. Weng, J. Yang, L. Avery, K.D. Dieckhaus, et al., A point- of-care microfluidic biosensing system for rapid and ultrasensitive nucleic acid detection from clinical samples. Lab Chip. 23 (2023) 3862–3873.

DOI: 10.1039/d3lc00372h

Google Scholar

[6] K. I. Sotowa et al. "Droplet formation by the collision of two aqueous solutions in a microchannel and application to particle synthesis". Chem. Eng. Technol. 30 (2007) 383–388.

DOI: 10.1002/ceat.200600345

Google Scholar

[7] B. Ahmed, D. Barrow, and T. Wirth. "Enhancement of reaction rates by segmented fluid flow in capillary scale reactors". Adv. Synth. Catal. 348 (2006) 1043–1048.

DOI: 10.1002/adsc.200505480

Google Scholar

[8] Zhun Lin et al. "Application of microfluidic technologies on COVID-19 diagnosis and drug discovery". Acta Pharmaceutica Sinica B. 13.7 (2023) 2877–2896.

DOI: 10.1016/j.apsb.2023.02.014

Google Scholar

[9] M. A. Northrup et al. "DNA amplification with a microfabricated reaction chamber". In: Transducers '93: Digest of Technical Papers, Proceedings of the 7th International Conference on Solid-State Sensors and Actuators. Yokohama, Japan, 1993.

Google Scholar

[10] S. Wiedemeier et al. "Parametric studies on droplet generation reproducibility for applications with biological relevant fluids". Engineering in Life Sciences 17.12 (2017) 1271–1280.

DOI: 10.1002/elsc.201700086

Google Scholar

[11] A. Lashkaripour, C. Rodriguez, N. Mehdipour, et al. "Machine learning enables design automation of microfluidic flow-focusing droplet generation". Nature Communications. 12 (2021) 25.

DOI: 10.1038/s41467-020-20284-z

Google Scholar

[14] P. Zhu, L. Wang, Passive and active droplet generation with microfluidics: a review. Lab on a Chip. 17 (2017) 34–75.

DOI: 10.1039/c6lc01018k

Google Scholar

[15] B. Rostami, G.L. Morini, Generation of Newtonian and non-Newtonian droplets in silicone oil flow by means of a micro cross-junction. International Journal of Multiphase Flow. 105 (2018) 202–216.

DOI: 10.1016/j.ijmultiphaseflow.2018.03.024

Google Scholar

[16] F. Azzini, B. Pulvirenti, M. Rossi, G.L. Morini, Squeezing Droplet Formation in a Flow-Focusing Micro Cross-Junction. Micromachines. 15 (2024) 339.

DOI: 10.3390/mi15030339

Google Scholar