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Hydrogen Properties for Energy Research (HYPER) Laboratory Yulia K. Gitter

Yulia K. Gitter


I grew up always looking up to the blue skies. I envied the birds. They had the freedom to go wherever they pleased. No boundaries. No limitations. No concept of the impossible. As I got older, flight became as mundane as a car ride. I would drift in and out of sleep as the calm hum of the propeller drifted the plane through the sky. Until suddenly, a whoosh of air would flood the plane, and we were all getting out. Hundreds of one-way plane rides and hours of daydreaming later, I started to question: Why wasn’t this little aircraft filled with some kind of renewable? I had no idea where to start…


I graduated with a Bachelors of Science in Mechanical Engineering and Bachelors of Arts in German from Washington State University in December 2021. I went to classes with the ever looming question of how would I get renewable energy into the aviation industry. It wasn’t until my junior year when I took Dr. Jacob Leachman’s Fundamentals of Thermodynamics class and found out about the HYPER Lab and Genii, the first hydrogen capable flight drone to be developed by a university. I immediately knew… Liquid hydrogen was the answer and I needed to get a spot in the lab if I wanted to make it happen. Liquid hydrogen’s low mass coupled with it’s high specific energy density makes it an ideal candidate to be integrated into air vehicles. I got a position as an undergraduate and quickly got to work asking questions and learning all the necessary technical skills to function in the lab. As I came close to graduation, I realized there were still large gaps in knowledge with understanding the fluid properties of liquid hydrogen. I had learned technical skills but still did not truly know what was going on at a fluids property level. I needed to know more…


One of the major challenges with integrating liquid hydrogen into any fueling system is the large temperature differential between a fluid and gas state from 20K to 293K. The expansion of the fluid vaporizing when in contact with a hot surface results in significant pressure oscillations that presents uneven flow distribution and ruptures components. The utilization of liquid hydrogen by a downstream consumer also poses challenges for even flow distributions when there is a gradual pressure decrease in the system as the fuel is used. There is little known for liquid hydrogen flow restrictors such as porous media throttles, nozzles, and jet pumps to alter the fluid flow conditions to be utilized by downstream consumers. My research focuses on developing better models for liquid hydrogen flow predictions through flow restrictors and validating them by developing small scale systems that can be tested using our Gen2 Mobile Hydrogen Generation Unit.