Nucleate Boiling Heat Transfer on Hybrid Surfaces

1. Figure 1
Figure 1 image is from
("Incropera, Frank. Fundamentals of Heat and Mass
Transfer 6th Edition. John Wiley and Sons, 2011“)
Nucleate boiling occurs when the surface temperature is
hotter than the saturated fluid temperature. During this
phenomenon, many bubbles will start to form repeatedly
creating many nucleic sites. This phenomenon is known
as nucleation. At this regime, the heat flux (q”) and heat
transfer (H) increase sharply with temperature (ΔT). The
nucleation ends once the temperature of the material
reaches a critical heat flux. Once the material passes the
critical heat flux, it is irreversible; therefore, the goal of
our experiment is to find a way for the material to
maintain a high level of heat flux as the
temperature increases.
We are exploring the thermal effect of epoxy
to see if material selectively coated with epoxy
can maintain a high heat flux.
Nucleate boiling is crucial for many
engineering application. Nucleate Boiling is
use for:
 Power generation,
 Electronic component cooling,
 Fluid handling and control.
 We found that material selectively coated with epoxy forms
individual heating zones creating a irregular temperature
distribution over a surface. This helps the materials’ to maintain a
high heat flux point and not drop as ΔT increases.
 The temperature doesn't shoot up rapidly as you do not enter in
the film boiling regime.
 This coating doesn't ensure the high heat flux but it shows a
better performance at high temperatures.
 We conclude that material coated with epoxy can operate at
much higher temperatures compares to pure material. I would like to give my greatest gratitude to all
people that contributed in the completion of this
project. I would like to thank the Howard Hughes
Medical Institute and Dr. Ashleigh Wright for
providing me the grant and resources to complete
this project. I also thank the faculty of the
Mechanical Engineering Department at Louisiana
State University including Dr. Shengmin Guo as
my advisor, Mr. Manish Patil as my mentor, and
Mr. Lance Brumfield as my technical supporter.
Material 1 Material 2
(Pure Brass) (Epoxy Coated Brass)
For our experiment we use a smaller surface area for the epoxy coated brass
compares to the pure brass. Since heat flux is also proportional to surface area if
we were to increase the surface area of epoxy brass we can expect a better result.
1. Machine the pin type patterns on the sample and add the epoxy
layer.
2. Set up the sample in the nucleation chamber applying the thermal
grease at the bottom.
3. Fill the chamber using FC-72 as a boiling medium.
4. FC 72 as fluid and nucleation chamber to create boiling.
5. Purge the chamber with Argon to avoid contamination.
6. Set the constant heat flux value and record the temperature when
it reaches to steady state.
7. Use Multilog 720 to measure temperature and heat flux.
8. Ensure that there is no leakage of FC72 during the experiment.
9. Ensure that nucleation chamber is in equilibrium during the
experiment.
Figure 2 image is from
(https://rs2007.limsi.fr/TSF__Interface_tracking.html
(Figure 2)
Procedure
Samples
Result/Conclusion
AcknowledgementMotivation–Theory/Plan
Abstract
Nucleate Boiling Analyzing Heat Transfer on Hybrid Surfaces
David Van Nguyen1, Manish Patil,2 Shengmin Guo,2*
1Baton Rouge Community College, Baton Rouge, LA 70803
2Department of Mechanical Engineering, Louisiana State University, Baton Rouge, LA 70803