Optimization of nanosecond transient plasma ignition for clean combustion

Low-temperature plasmas generated by nanosecond electrical pulses, also referred to as transient plasmas, can be used to significantly improve fuel efficiency and reduce emissions by enabling stable ignition in gasoline and natural gas engines in dilute conditions (e.g. applications such as methane capture, where methane is captured from landfills and burned to produce electricity) as well as through direct exhaust remediation for all fuel burning engines, including diesel. Nanosecond pulsed power systems support these applications via highly attractive features compared to other approaches (e.g. RF and microwave plasmas), however, key pulsed power parameters and their relations to plasma properties and chemistry remain unknown and require systematic studies that will result in optimized systems for these applications. Recent studies suggest that increased dV/dt (reduced rise-time) increases the ionization during plasma initiation, enhances the electron impact reactions that result in greater production of reactive oxygen species6, such as O and OH. Yet, a systematic study, or a true a-to-b comparison with fixed pulse duration and multiple rise times has not been done in this field, primarily because of the technical challenge and complexities of developing nanosecond pulsed power systems to meet the specifications. Transient Plasma Systems (TPS) specializes in U.S. made nanosecond pulsed power systems. TPS entered the commercial market in 2009 with products designed for laboratory applications and basic science research, and is now preparing to expand its product offerings to include a commercial plasma ignition system. TPS will team with the Plasma and Pulsed Power Group at Old Dominion University (ODU). During the Phase I, TPS will (1) design and develop nanosecond pulsed power systems driven by a nanosecond pulse duration with two varying rise times, and ODU will (2) perform transient plasma ignition studies using the developed systems and assess the impact of the pulsed power parameters on the production of O and OH via advanced diagnostic techniques. During Phase II, additional optimized systems will be developed and tested. In order to achieve multiple discrete rise times for a given set of fixed pulse parameters TPS will utilize an assortment of internally developed pulse forming techniques. TPS has experience in crossing the bridge between basic science and fabrication, with its technology being demonstrated in engine applications in multiple labs, including Sandia National Lab’s Combustion Research facility and Argonne National Lab, as well as with engine manufacturers. Phase I development will occur at TPS, and the plasma diagnostics will be performed at Old Dominion University. In Phase II and beyond, TPS will work with strategic partners to develop a product for use in engines, and it will sell or license this technology to support rapid growth and deployment. This will allow TPS to leverage this revenue stream to switch emphasis and develop technology for the next accessible market, such as dental sterilization, maximizing the impact of this technology on U.S. and global challenges of health and emissions.