Plasma Discharge Morphology in a Thin Stream Packed Bed DBD with Turbulence Effects

Turbulent flows in plasma discharges can provide several potential advantages for water purification applications, including enhanced surface area, local electric field enhancements, islands of trapped surface charge, and increased mixing both in the gas and liquid phases. All of these can enhance effective plasma dose as an advanced oxidation/reduction process, which is necessary to scale up plasma systems to real world applications. In the UM Packed Bed Reactor (PBR) [1], in which thin water streams serve as the packing medium, it has been observed that the discharge morphology and liquid phase chemistry are altered with changes in flow rate, corresponding to turbulence, with the same plasma electrical input. The interaction of plasma discharge with the water stream as a function of turbulence is not well understood. This work aims to characterize the discharge morphology as a function of flow rate in a single stream packed bed dielectric barrier discharge (DBD). With no plasma, laser scattering techniques along with fast imaging will be employed to understand the nature of the flow as well as gas phase mixing. With plasma on, optical emission spectroscopy and fast imaging will be used to understand the discharge morphology and plasma parameters.

References: [1] Foster, J. E., Mujovic, S. 2020, U.S. Patent No. 10,662,086, Washington, DC: U.S. Patent and Trademark Office.