(6fd) Deep Learning in Dynamic and Complex Systems

Transport Phenomena at Microscopic
Scales and their Effects on Macroscopic Scale Processes

1)    
Research Interests:

Research
Interests

Understanding
transport phenomena is important to many processes both living and non-living.
New technology in fabricating nano- and micro-structures allows us to control
the transport process from the nano- and micro-levels, and therefore the whole
process at the macroscopic scale. This strong connection between what happens
at the microscopic scale and the macroscopic scale opens many opportunities for
scientists in the transport phenomena field to make current processes more
efficient, create new processes, and gain new fundamental knowledge.
Understanding what happens at microscopic scales will help us reach the next
step of more advanced technology. I want to focus my academic career on
studying the transport phenomena at microscopic scales and their effects on
macroscopic scale processes.

Research
Experience

During
my Ph.D. research, in collaboration with NASA, I studied the interfacial forces
and fluid dynamics in a wickless heat pipe in microgravity at both macroscopic
and microscopic scales. On Earth, gravity dominates over Marangoni force. But
in microgravity, Marangoni and capillary forces control fluid flow in the heat
pipe. At the macroscopic scale, the strong Marangoni flow created a flooded
region instead of dry-out near the heater end of our heat pipe on the ISS. At
the microscopic scale, we found that the large Marangoni force in the region
near the heater end generated instability in the liquid film on the wall
surface which led to condensation at an anomalously high temperature. We developed
a numerical model to understand this phenomenon and found that oscillation can
enhance net evaporative heat transfer if a short period of condensation exists
within each oscillation cycle. The effects of capillary and Marangoni forces
continued to amaze us, both in their microscopic dynamics and their macroscopic
impact on heat pipe performance. Analyzing the interferometry pattern, we
discovered a fluid flow pattern inside the heat pipe that mimics “rip currents”
along shore lines. This rip current pattern helps to release the heat supplied
to the heater end. To reduce the effect of the Marangoni force, we added a
second component to the working fluid and increased the heat transfer
coefficient significantly. This knowledge about interfacial phenomena in microgravity
is extremely important to understanding fluid mechanics within microsystems on
Earth where the effect of gravity is small.

My
Ph.D. training gave me a solid background in transport processes with a focus
on interfacial phenomena and thin film. It taught me the importance of
combining experimental work, analytical and theoretical analysis, and
simulation to solve problems and gain new understanding. I am a scientist who
is always on the lookout for opportunities to expand my skills and knowledge,
and I’m excited about unexpected results because that is where we discover new
phenomena.

To
expand my knowledge in transport processes I joined a team of thermal engineers
at Corning Inc. in 2017. I got the opportunity to do both fundamental research
and process development work. On the research side, I’m leading a mid-sized
project to study the heat transfer process during glass forming. On the
development side, I work in a large team of thermal management experts to
study, develop, and improve full-size production processes. My experience in
industry gave me a practical view of transport phenomena and showed me how
fundamental knowledge gained from academic research is used in real production.
I also learned the importance of using simulation to guide experimental work.
These experiences show how the transport phenomena at microscopic scales
affects full-size processes and how important it is to understand what happens
at microscopic scales.

Future
Direction

In
the next step of my career, I will focus on understanding transport phenomena
at both microscopic and macroscopic scales in different directions. I will
incorporate both experimental and simulation work in my research.

The
first direction is thermal management. With the continuing increase in heat
dissipation of computer chips and power electronics, the need for more
efficient electronic cooling systems is critical. Oscillating heat pipes (OHP)
have the advantage over traditional heat pipes in that the flows of liquid and
vapor are separated. The oscillatory flow of liquid and vapor plugs also offers
an additional mechanism for heat transfer. However, the inherent instability of
the OHP keeps it from being used widely. Also, only less than 10% of heat
transfer in an OHP is from latent heat.  I’d like to develop micro-structures
inside the OHP so that the heat transfer process can be manipulated and
improved at the microscopic scale, leading to better performance at the
macroscopic scale. The knowledge gained from this research can be used to improve
many other processes including other forms of heat pipe, boiling heat transfer,
and transport processes in thin films. 

The
second direction is microfluidic bio-separation. Separation and accurate
identification of highly valuable biomarkers that are present at micro-and
nano-levels becomes critical for disease diagnostics. Traditional separation
devices require large sample volumes, are relatively time-consuming, or limited
to only several separation techniques. Microfluidic devices are becoming promising
alternatives that can overcome these shortcomings of traditional devices. The
efficiency of the microfluidic devices depends strongly on the nano- and
micro-structures of the stationary phase materials and the ligands immobilized.
This is a perfect niche to utilize my background in chemistry, biochemistry,
and transport processes. The knowledge gained in this direction will also
complement my work in thermal management.

Beyond
these directions, I continue looking for other systems where the transport phenomena
at microscopic scales affect the macroscopic processes. 

2)    
Teaching Interests:

 Everyone has a unique, inner
creativity and the desire to better themselves. I believe that the job of a
teacher is to create an environment that fosters this creativity and desire.
The role of teacher requires that we guide each student in the direction that
is right for that student. We should make sure students have a strong
fundamental understanding of the subject and know how to apply it to solve the
real world problems they’ll face in their careers. Technology changes at the
speed of light. The ability to self-motivate, independently learn new material,
and apply it to the problem at hand is more important than ever.

I come from a family of teachers,
where I’ve been taught to see the unique path that every student will take.
I’ve been building my teaching philosophy with this idea at the forefront, and
I’ve developed methods to help me follow it. RPI gave me a chance to learn what
works, and what doesn’t, so I could refine my methods and hone my skills. At
RPI, I was a teaching assistant for five courses in the Chemical Engineering
Department, the Biology Department, and the Mathematical Sciences Department. I
mentored seven undergraduate and graduate students from RPI and three students
visiting from other universities. They each went down a different road in life.
Some work in different industries and some are pursuing their Ph.D. programs at
Ivy League schools.  Each of these students had a passion for how they wanted
to be successful, and enabling students to accomplish their goals by following
their paths was one of the most rewarding experiences I had as a mentor.

3)    
Proposal Writing
and Funding Management Experience

·        
Leading and managing funding for a mid-sized research project at
Corning Inc.

·        
Writing a proposal with Prof. Joel Plawsky to form collaboration
between RPI and Corning Inc.

4)    
Industry Experience

·        
Corporate Thermal Engineer, Corning Inc., Corning, NY (2017 –
present).

·        
Research project: Leading a mid-sized research project on
studying the heat transfer process during glass forming.

o   Conducted literature
search to develop initial scope and methods.

o   Formed a team
of engineers from different departments to develop decision analysis and project
timeline.

o   Working with
the team to design, build, and test the equipment and run experiments.

o   Building analytical
model in COMSOL to analyze results and create final model.

·        
Development project: Working on one of the largest and most
visible projects in the company.

o   Working with
top researchers and engineers in the field to develop new production processes
for a critical customer.

o   Developing large
scale thermal management techniques to achieve desired material properties.

o   Conducting
experiments and proposing solutions for process improvement.

o   Collaborating
with people from different backgrounds and skill sets from the plant, division,
and corporate engineering teams.

5)    
Ph.D. Dissertation

“The Constrained
Vapor Bubble heat pipe: interfacial forces at both macroscopic and microscopic
scales”.

Under the supervision of Prof. Joel L.
Plawsky and Prof. Peter C. Wayner, Jr.

·        
2018 Karen and Lester Gerhardt Best Thesis Prize.  

·        
2018 William N. Gill Prize for Excellence in Dissertation Research.

6)    
Publications

(“*” denotes equal
contribution.)

1. Nguyen, T., Plawsky, J., Kundan, A., Wayner Jr., P., Chao, D., Sicker, R. Rip currents in microgravity. (Submitted to PNAS).
2. Nguyen, T., Yu, J., Plawsky, J., Wayner Jr., P., Chao, D., Sicker, R. Spontaneously oscillating menisci: Maximizing evaporative heat transfer by inducing condensation, Int. J. Thermal Sciences, 128 (2018) 137-148.
3. Plawsky*, J., and Nguyen*, T. Wickless heat pipes in microgravity, Physics Today, 70, 9, 82 (2017). Invited article.
4. Kundan*, A., and Nguyen*, T., Wayner Jr., P., Plawsky, J., Chao, D., Sicker, R. Condensation on highly superheated surfaces: wickless heat pipe operation in microgravity, Phys. Rev. Lett., 118 (2017) 094501. PRL Editors' Suggestion. Featured in PHYS.ORG.
5. Nguyen, T., Kundan, A., Wayner Jr., P., Plawsky, J., Chao, D., Sicker, R. Experimental study of the heated contact line region for a pure fluid and binary fluid mixture in microgravity, J. Colloid Interface Sci.,488 (2017) 48-60.
6. Nguyen, T., Kundan, A., Wayner Jr., P., Plawsky, J., Chao, D., Sicker, R. The effect of an ideal fluid mixture on the evaporator performance of a heat pipe in microgravity, Int. J. Heat Mass Transfer, 95 (2016) 765-772.
7. Nguyen, T., Kundan, A., Wayner Jr., P., Plawsky, J., Chao, D., Sicker, R. Effects of cooling temperature on heat pipe evaporator performance using an ideal fluid mixture in microgravity, Exp. Therm. Fluid Sci., 75 (2016) 108-117.
8. Yu, J., Nguyen, T., Plawsky, J., Wayner Jr., P., Chao, D., Sicker, R. The effect of cooling temperature on the interfacial forces in a wickless heat pipe in microgravity. (In preparation).
9. Kundan, A., Nguyen, T., Wayner Jr., P., Plawsky, J., Chao, D., Sicker, R. Arresting the phenomenon of heater flooding in a wickless heat pipe in microgravity, Int. J. of Multiphase Flow, 82 (2016) 65-73.
10. Popov, Yu., Mokhov, V., Nguyen, T., Direct alkylation of amines by alcohols with catalysis by nickel and cobalt nanoparticles, Inter-university collection of scientific articles, Higher Attestation Committee (HAC) of the Ministry of Education and Science of the Russian Federation (MESRF), Apr. 2011.
11. Mokhov, V., Popov, Yu., Nguyen, T., The reaction of alkyl halides with 2, 4-pentanedione catalyzed by copper nanoparticles, Inter-university collection of scientific articles, HAC of MESRF, Apr. 2011.