Performance tuning of microfluidic flow-focusing droplet generators

Lab on a Chip ◽  
2019 ◽  
Vol 19 (6) ◽  
pp. 1041-1053 ◽  
Author(s):  
Ali Lashkaripour ◽  
Christopher Rodriguez ◽  
Luis Ortiz ◽  
Douglas Densmore
Keyword(s):  
Droplet Size ◽  
Design Space ◽  
Performance Tuning ◽  
Generation Rate ◽  
Flow Focusing ◽  
Microfluidic Flow ◽  
Droplet Generators

We explored a large design space to identify the coarse/fine tuners in determining droplet size, generation rate, regime, and polydispersity.

Droplet size prediction in a microfluidic flow focusing device using an adaptive network based fuzzy inference system

2020 ◽  
Vol 22 (3) ◽  
Author(s):  
Sina Mottaghi ◽  
Mostafa Nazari ◽  
S. Mahsa Fattahi ◽  
Mohsen Nazari ◽  
Saeed Babamohammadi
Keyword(s):  
Droplet Size ◽  
Fuzzy Inference System ◽  
Fuzzy Inference ◽  
Flow Focusing ◽  
Adaptive Network ◽  
Inference System ◽  
Microfluidic Flow

scholarly journals Modeling of Droplet Generation in a Microfluidic Flow-Focusing Junction for Droplet Size Control

Micromachines ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 590
Author(s):  
Ali M. Ibrahim ◽  
Jose I. Padovani ◽  
Roger T. Howe ◽  
Yasser H. Anis
Keyword(s):  
Numerical Model ◽  
Droplet Size ◽  
Size Control ◽  
Continuous Phase ◽  
Immiscible Fluids ◽  
Droplet Generation ◽  
Flow Rate Ratio ◽  
Flow Focusing ◽  
Flow Rates ◽  
Microfluidic Flow

In this paper, we study the parameters that affect the generation of droplets in a microfluidic flow-focusing junction. Droplets are evaluated based on the size and frequency of generation. Droplet size control is essential for microfluidic lab-on-a-chip applications in biology, chemistry, and medicine. We developed a three-dimensional numerical model that can emulate the performance of the physical system. A numerical model can help design droplet-generation chips with new junction geometries, different dispersed and continuous phase types, and different flow rates. Our model uses a conservative level-set method (LSM) to track the interface between two immiscible fluids using a fixed mesh. Water was used for the dispersed phase and mineral oil for the continuous phase. The effects of the continuous-to-dispersed flow rate ratio (Qo/Qw) and the surfactant concentration on the droplet generation were studied both using the numerical model and experimentally. The numerical model was found to render results that are in good agreement with the experimental ones, which validates the LSM model. The validated numerical model was used to study the time effect of changing Qo/Qw on the generated droplet size. Properly timing when the flow rates are changed enables control over the size of the next generated droplet, which is useful for single-droplet size modulation applications.

Formation of Polyacrylamide and PEGDA Hydrogel Particles in a Microfluidic Flow Focusing Droplet Generator

2018 ◽  
Vol 63 (9) ◽  
pp. 1328-1333
Author(s):  
D. V. Nozdriukhin ◽  
N. A. Filatov ◽  
A. A. Evstrapov ◽  
A. S. Bukatin
Keyword(s):  
Droplet Generator ◽  
Flow Focusing ◽  
Hydrogel Particles ◽  
Microfluidic Flow

scholarly journals Asynchronous generation of oil droplets using a microfluidic flow focusing system

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Peter Thurgood ◽  
Sara Baratchi ◽  
Aram Arash ◽  
Elena Pirogova ◽  
Aaron R. Jex ◽  
...  
Keyword(s):  
Flow Focusing ◽  
Oil Droplets ◽  
Microfluidic Flow

scholarly journals Breakup Dynamics of Semi-dilute Polymer Solutions in a Microfluidic Flow-focusing Device

Micromachines ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 406
Author(s):  
Chun-Dong Xue ◽  
Xiao-Dong Chen ◽  
Yong-Jiang Li ◽  
Guo-Qing Hu ◽  
Tun Cao ◽  
...  
Keyword(s):  
Relaxation Time ◽  
Polymer Solutions ◽  
Newtonian Fluids ◽  
Droplet Microfluidics ◽  
Droplet Generation ◽  
Flow Focusing ◽  
Polymeric Fluids ◽  
Practical Applications ◽  
Dilute Polymer Solutions ◽  
Microfluidic Flow

Droplet microfluidics involving non-Newtonian fluids is of great importance in both fundamental mechanisms and practical applications. In the present study, breakup dynamics in droplet generation of semi-dilute polymer solutions in a microfluidic flow-focusing device were experimentally investigated. We found that the filament thinning experiences a transition from a flow-driven to a capillary-driven regime, analogous to that of purely elastic fluids, while the highly elevated viscosity and complex network structures in the semi-dilute polymer solutions induce the breakup stages with a smaller power-law exponent and extensional relaxation time. It is elucidated that the elevated viscosity of the semi-dilute solution decelerates filament thinning in the flow-driven regime and the incomplete stretch of polymer molecules results in the smaller extensional relaxation time in the capillary-driven regime. These results extend the understanding of breakup dynamics in droplet generation of non-Newtonian fluids and provide guidance for microfluidic synthesis applications involving dense polymeric fluids.

Sign in / Sign up

Export Citation Format

Share Document