Title:

Combustion for Sustainable Transportation

Abstract:

Despite important electrification efforts, the United States Energy Information Agency projects that, for the foreseeable future, liquid hydrocarbons and biofuels will continue to provide >95% of transportation energy. Moreover, outside of the U.S., the European Union has set a target of 27% for renewable energy in the transportation sector, as proposed in the 2030 Framework for Climate and Energy, which is stated to be met only by partially or completely replacing fossil fuels with biofuels. Building on the global recognition that combustion-derived energy will remain critical to the transportation sector, continued development of advanced combustion technologies plays a meaningful role in sustainably meeting rising energy demands while also mitigating near-term air quality and climate impacts.

Gas-phase combustion remains central to producing new insight on structure-reactivity behavior of hydrocarbons and biofuels under conditions of temperature and pressure that reduce both the carbon intensity and resulting pollutants of the transportation sector. Such conditions elevate the role of carbon-centered, hydroperoxy-substituted radicals (Q ̇ OOH), an elusive class of species that undergo either bimolecular reaction with O2 or unimolecular reaction into isomer-specific products including cyclic ethers.

The presentation focuses on two aspects of cyclic ethers (1) the competing sets of reactions neglected in conventional gas-phase combustion models and (2) the central role of cyclic ethers in the formation of oxygenated primary organic aerosol (OxyPOA). The latter is mechanistically distinct from primary organic aerosol (POA) emitted during high-temperature combustion (soot) and, importantly, is chemically similar to secondary organic aerosol (SOA). The distinction is relevant due to historical underpredictions of SOA by atmospheric models and because radiative forcing differences of aerosols depend on the degree of particle oxidation.

The Paul M. Rady Department of Mechanical Engineering Distinguished Seminar Series features scholars from a wide range of peer institutions across the country. The events are open to all faculty, staff and students looking to spark their curiosity and learn about high-impact research from some of the world's most prominent experts in mechanical engineering.