High-temperature gas-phase chemistry, such as the chemistry responsible for powering engines and supplying electricity from power plants to homes, is complicated. But it is critical to understand these chemical processes to make advancements in energy efficiency and pollution reduction. Few experiments exist that can get a full chemical picture of the chemistry occurring in complex reacting systems, since many of the critical molecular species formed are unstable with very short lifetimes. This work focuses on the development of new micro-reactors that can probe the chemistry on the order of microseconds to directly measure the fundamental chemistry of gas-phase reactive systems. When coupled with other diagnostics, these micro-reactors will give a nearly full chemical picture of the chemistry that occurs. If successful, these proposed micro-reactors will be a valuable research tool that will significantly enhance the ability of the field to measure the chemical products of gas-phase reactions, leading to more accurate kinetic models with wide ranging applications from engine design to air quality modeling.
The objective of this proposed work is to design and fabricate a novel micro-reactor for advanced chemical diagnostics for combustion and gas-phase reactive flows. While micro-reactors have been used to study pyrolysis (thermal decomposition) reactions previously, these reactors are limited in their experimental capabilities due to the reactive nature of the base material, silicon carbide (SiC) with oxygen and uncertain pressure and temperature conditions in the reactor. To directly address these issues, computational analysis will be employed to redesign the geometry of the reactor to produce stable thermodynamic fluid properties within the reactor, leading to accurate determination of reaction temperature and pressure. Then, these reactors will be fabricated using a combination of 3-D printing, casting, and micro-drilling methods. Two sets of reactors are planned: one set will be made of SiC for comparison to existing pyrolysis reactors and a second set will be made of non-reactive materials, such as quartz or sapphire, for fuel oxidation study. Performance characterization of these reactors will be completed through a series of experiments that probe the temperature and pressure behavior of fuels in a reactive environment. This powerful new instrument has the potential to help unravel still unanswered questions such as how soot is formed and destroyed, what are the dominant reaction paths for ignition, and how do pollutants interact with ozone in the upper atmosphere.
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.
