Publication Date


Document Type


Committee Members

Ed Alyanak (Committee Member), Rory Roberts (Advisor), Scott Thomas (Committee Member), Mitch Wolff (Advisor)

Degree Name

Master of Science in Mechanical Engineering (MSME)


Many technological advances are expected to increase the capabilities of the future aircraft, both civilian and military. These improvements come in many forms such as new wing or fuselage shapes to improve lift or decrease drag. Other improvements are internal. One of these areas is the inclusion of advanced electronic systems for various roles. These changes affect a wide range of aircraft systems including, but not limited to avionics, power generation and thermal management. While these modifications promise to increase aircraft capabilities such as its range, payload or other key performance parameters, there are some significant drawbacks. One drawback is the thermal and power requirements needed to meet these needs. This problem will only be amplified by the addition of a High Energy Pulsed System (HEPS). This improvement, along with existing electronic systems that could be featured on next generation aircraft could cause a significant thermal load on an aircraft, where heat dissipation is already a problem. HEPS of this sort generate excessive amounts of heat during operation, creating an aircraft integration problem that might overwhelm the vehicles thermal management systems. Using the innovative solution of cryogenically cooling the HEPS, the proposed system would use Liquefied Natural Gas (LNG) as the system's primary coolant. In order to accomplish this, preliminary studies were carried out which indicated that the cryogenic cooling system for a HEPS could possibly be of a reasonable size for an aircraft application. Following this, detailed MatLab/Simulink models were made of the required cryogenic components so that they could be integrated into a T2T model to analyze the vehicle level effects of the LNG system. An initial aircraft integrated LNG HEPS system was designed and the results showed the HEPS was cooled and the rest of the aircraft also received a cooling effect. Further studies have enhanced that effect and attempted to accomplish the same cooling capability as the baseline aircraft, while using the LNG more efficiently. These studies show that LNG is indeed capable of thermally managing the entire aircraft effectively with a reasonable amount of LNG. Additionally, the designed architecture that cooled the entire aircraft with LNG showed that it could cope with the anticipated increase in thermal demands over time by simply adding additional LNG capacity. Finally, an architecture was designed that would take full advantage of LNG as a fuel. This palletized system uses the LNG to fuel a micro gas-turbine which in turn provides electricity to the HEPS and other systems directly connected to the LNG system. This proposed architecture is a good platform to investigate the transient concerns of startup, shutdown and other operating points of the system for various missions. In summary, LNG has shown itself to be an effective coolant and a distinct possibility as a solution to rapidly increasing power and thermal demands aboard aircraft, which deserves further in depth experimentation and study to develop a viable system.

Page Count


Department or Program

Department of Mechanical and Materials Engineering

Year Degree Awarded


Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License.