CAREER: Low-Temperature Plasma Assisted Combustion of Oxygenated Fuels for Cleaner and Sustainable Mobility

Auburn University, Auburn AL

Investigators

Abstract

Concurrent development of electric vehicles, along with next-generation engines using renewable biofuels has shown to be an effective strategy to meet the energy demands and improve the future sustainability of the transportation sector. However, achieving reliable combustion with fuels that exhibit a large selection of oxygenated components, at highly fuel-lean conditions, across the operational domain of the engine has proven a technological challenge. Low-temperature plasmas (LTP) are seen as an enabling technology to overcome this barrier, due to their demonstrated ability to enhance combustion, provide fast-gas heating and facilitate flame kernel growth. But there remains a knowledge gap on the interaction between plasmachemical effects and the basic combustion phenomenon to effectively couple the utilization of LTP and biofuels. Leveraging unique experimental platforms and modeling tools tailored for plasma-assisted combustion (PAC) research, this project aims to uncover these chemical fundamentals that could demonstrate enhanced chemical reactivity, improved energy extraction and ignition, with reduced pollutant formation. The results from this project will be shared openly with both academia and industry to support LTP innovation and have an immediate impact on combustion engineering for vehicular, aerospace and energy-related applications, with overarching benefits towards economic globalization and developing economies. To integrate LTP combustion research and education, this project will: (1) leverage game-based learning to progressively engage the undergraduate/graduate curriculum to introduce new knowledge; (2) engage with a K-12 outreach program to broaden the participation of underrepresented STEM students; and (3) disseminate research findings to the general public by developing a new animation video with emphasis on the importance of energy sustainability, while educating on its social, political and economic implications. LTP-based technologies are essential to advance next-generation internal combustion engines toward renewable biofuels and dilute-burn strategies. This project addresses the lack of fundamental understanding of plasmachemical effects on combustion reactivity and ignition characteristics, and adds a new emphasis on oxygenated fuels. This work also provides a new demonstration of the merits of LTP to improve combustion engineering. These contributions will be achieved through a study of LTP plasmachemical effects on the low-temperature combustion (LTC) reaction kinetics of oxygenated fuels and ignition characteristics, and subsequent implications on pollutant formation and dilute-burn reactivity. Outcomes will be demonstrated through plasma-coupled experimental facilities and numerical models to measure key chemical species and combustion metrics, and simulate important reactions to elucidate an understanding of: (1) the alteration of LTC chemical reactivity by LTP for a range of oxygenated fuels based on oxygen functionality; (2) subsequent alteration of LTC reactivity in the presence of residual gas components and pollutant formation kinetics; (3) the alteration of ignition and heat-release characteristics of oxygenated fuels toward fuel-lean and dilute-burn conditions; and (4) development of a PAC-specific kinetic mechanism for predictive simulation tools. This contribution is significant because it is expected to constitute a progression of research that is currently lacking to demonstrate the ability to alter the chemical reactivity of high-octane oxygenated fuels through LTP. Ultimately, this research will support LTP as a technology to enable reactivity control for advanced compression-ignition engines and drive future designs toward renewable biofuels to achieve a sustainable future for mobility. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.