BioMEMS Microfluidics Final Presentation

1. BioMEMS Microfluidics Mixer
Final Presentation
4/28/2011
K.M.Broughton

2. Outline
 Microfluidic Mixer Design
 Microfluidic Mixer Initial Thoughts
 Trapezoid Mixer Design
 Variation to Parameters
 Variation to match Fabrication
 Simulation Results
 Inlet Variations Parameters Explored
 Experimental Results
 Simulation v. Experimental Analysis
 The Good, The Bad, and the Lessons Learned

3. Microfluidic Mixer Initial Thoughts

4. Trapezoid Design Mixer
50 µm
 Variables
 Inlet Profile
 Channel Width
 Angles
 Height
800 µm 30°
 Length
400 µm
 Simulations
 Approximately 25 simulations run on various variables
 Found Optimized Geometry for “Perfect” Mixing
 Fabricated Design
 Chose design that was not optimized via simulations but was
likely similar to the actual experimental result
Optimized Concentration Profile

5. Base Variation – Velocity Profiles
310 micron length
344 micron length
388 micron length
440 micron length
Optimized

6. Base Variation – Concentration Profiles
310 micron length
344 micron length
388 micron length
440 micron length
Optimized

7. Example of Manipulation to
Simulation via Height Variation

8. Inlet Variation – Velocity Profiles
Single T Inlet
Double T Inlet
Single Y Inlet
Double Y Inlet
Independent Inlet

9. Inlet Variation – Concentration Profiles
Single T Inlet
Double T Inlet
Single Y Inlet
Double Y Inlet
Independent Inlet

10. Inlet Variation
Inlet Variations - Concentration line analysis
85%
75%
Concentration percent
65% Double T
Double Y
55%
Y inlet
45%
T inlet
35% Optimal
25%
15%
1 14 27 40 53 66 79 92 105 118 131 144 157 170 183 196
Position - each marker is valued at .25 microns

11. 3D Modeling of Double T Inlet

12. Simulation conformed to Experiment:
Velocity and Concentrations
Fast (rate .1 cc/min; Concentration profile range -50 to 50)
Medium (rate .0096 cc/min; Concentration profile range -1.5 to 1)
Slow (rate .009 cc/min; Concentration profile range -.2 to 1.4)

13. Simulation Results

14. Experimental Results – without Beads
Inlet Middle Outlet
Fast
(rate .1 cc/min)
Experimental
Medium
(rate .0096 cc/min)
Results – No Beads
Slow
(rate .009 cc/min)

15. Experimental Results – with Beads
Inlet Middle Outlet
Fast
(rate .1 cc/min)
Medium Experimental
(rate .0096 cc/min)
Results – With
Beads
Slow
(rate .009 cc/min)

16. Experimental Results

17. Simulation vs. Experimental Results

18. Simulation vs. Experimental Results
Slope Slope
0.035
0.0308
0.0297
0.03
0.0274
0.0248
0.025
0.02
0.02 0.0184
0.015
0.01
0.005
0
Fast Mid Slow Fast Mid Slow
Simulation Experimental

19. Simulation vs. Experimental Results
% Error Simulation v. Experiment
35
30
25
Percent Error
20
15
10
5
0
Fast Mid Slow
% Error 33.11688312 16.4983165 32.84671533

20. Results Conclusion
 Comsol Multiphysics
 Useful for Design work
 Easy to manipulate data to optimize
 Difficult to gauge actual findings
 Experiment compared to Simulations
 Liked approach of beads and no beads
 Would have liked running simulations with actual flow rates first
 Overall Conclusions
 Enjoyed have freedom to try many different design simulations
 Found simulations were not good gage for experiment results in this case
Optimized Concentration Profile

21. Thank You!