Brugia Malayi - Clark Science Center - Smith College

Modeling and Analysis of Thermal Dynamics in Miniature PEM Fuel Cells
Xinyi Liu
A fuel cell is a device that converts the chemical energy of a fuel into electricity. Every fuel cell consists of a cathode, an anode
and an electrolyte. The most commonly used fuel is hydrogen. When hydrogen reacts with oxygen, power is generated by the fuel
cell. The type of fuel cell used in our lab is a miniature Polymer Electrolyte Membrane Fuel Cell (PEMFC), with a catalyst coated
active area of 5cm 2 . Even though PEMFCs contain many advantages over other types of fuel cells, such as being lighter, more
compact, and responsive to dynamic loads, temperature and water management remain technical barriers to successful commercial
implementation.
A control-oriented mathematical thermal model was developed and experimentally validated to predict the thermal
performance of the miniature PEMFC, which operates with no humidification or reactant pre-treatment. After performing
control volume analysis and applying an energy balance for the cell, the thermal model was constructed in Simulink and analyzed
in MATLAB.
The miniature PEMFC was operated on a test bench under changes in load, air mass flow rate, and cathode inlet temperature.
With the experimental data obtained, the model was tuned to identify unknown parameter values, followed by an experimental
validation for that model. The thermal dynamic response of the model was compared with the experimental. Our model
accurately captures most of the changes in load and in air mass flow, but further modifications to the model still needs to be made.
The SURF summer research introduced me to the field of fuel cell study and provided me with a rich summer experience.
Under the guidance of my research advisor, I gained a deeper understanding of both fuel cell thermal-modeling techniques
and how to carry out academic research. The work we did during the summer has been submitted as a conference paper to the
ASME/IEEE American Controls Conference. With the knowledge built and techniques learned during the summer research,
I will continue work on the thermal dynamics modeling of our fuel cell in my junior year as a Special Study. (Supported by the
Schultz Foundation)
Advisor: Denise McKahn
2012
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