Microheater Array Boiling Experiment (MABE)
Research Area: Fluid Physics
Expedition(s): 25- 28
Principal Investigator(s): ● Jungho Kim, PhD, University of Maryland, College Park,
Maryland
RESEARCH OBJECTIVES
Boiling efficiently removes large amounts of heat by generating vapor from liquid; this process
is currently being used in many power plants to generate electricity. An upper limit, called the
critical heat flux, exists where the heater is covered with so much vapor that liquid supply to
the heater begins to decrease, potentially destroying the heater. Microheater Array Boiling
Experiment (MABE) determines the critical heat flux during boiling in microgravity to design
optimal cooling systems for future space exploration vehicles as well as on Earth.
EARTH BENEFITS
The proposed research has shown that transient conduction is the dominant heat transfer
mechanism in boiling of refrigerants-like fluids. This research will provide insight into creating
more efficient cooling systems on Earth.
SPACE BENEFITS
In microgravity, a bubble can cover
an entire heater array instead of
just a small area, resulting in
burnout of components if local hot
spots are present. The increased
spatial resolution of these
measurements will enable the
extent of the dry spot to be
measured along with the heat
transfer from the liquid surrounding
the dry spot. This technique can be
applied to other areas including
spray cooling, turbulence
measurements and flow boiling.RESULTS
MABE completed over 2 hundred
pool boiling tests aboard the ISS
between March and April 2011. In
the ISS microgravity environment,
the heat transfer mechanisms during bubble formation can be determined more accurately
since the level of g-jitter (ie, vibrations from the spacecraft, aboard machinery, and crew) is
much less than with short-duration experiments using sounding rockets or drop towers. Surface
tension dominated boiling (SDB), characterized by the formation of a non-departing coalesced
Microheater Array Boiling Experiment Image: High-speed video
image that is colorized with heater power data. Correlating the
position of the vapor and liquid positions with the heater power data
provides insight into the heat transfer and phase change
mechanisms. University of Maryland image.