Aviation accounts for roughly 12\% of the world’s CO2 emissions. A Boeing 777, using the full capacity of both fuel tanks, produces 1 million pounds of CO2, equivalent to the CO2 emissions generated by 130 cars in one year, assuming each vehicle is driven approximately 22,000 km annually. Given the significant number of flights, estimated at around 100,000 per day (excluding military and private jets), there is a pressing need for the scientific and engineering communities to take decisive action toward enabling electric aviation. The CarbonLess Electric Aviation (CLEAN) project, supported by NASA and led by researchers at Tennessee Technological University in collaboration with Boeing, Raytheon, Ohio State University, University of Dayton, Tennessee State University, University of Washington, and Special Power Sources, seeks to tackle this issue through the implementation of an innovative propulsion system. This system is powered by a solid oxide fuel cell that utilizes ammonia as its fuel source. Although this system effectively eliminates CO2 emissions, it poses potential climate challenges by potentially increasing cloudiness in the sky. Therefore, the Fluid Mechanics Research Lab’s main objective is to understand this aircraft’s contrail formation and evolution comprehensively. We also aim to assess its impact on radiative forcing and climate sensitivity. To achieve this, the team employs various analytical tools, including thermodynamic analysis, computational fluid dynamics, and mesoscale models, such as the Weather Research and Forecasting model.

FMRL’s contributions to the CLEAN project also involve the aerodynamic optimization of the aircraft. The existing airplanes are optimized assuming concentrated mass and propulsion, while the proposed electric propulsion allows the distribution of propulsion and mass. Hence, using the Geometry Optimization Platform, created by an FMRL graduate student, we plan to optimize the geometry as well as mass and propulsion distribution to achieve maximum aerodynamic performance.

We are also committed to contributing to workforce development via both outreach and curriculum development. Please check the “outreach” tab of the website to learn more about our outreach contributions.