DBD Plasma Jet Characterization Using Plasma Luminosity and Emission Spectroscopy

Kathy Hoang, Sohail Zaidi, Department of Mechanical Engineering, San Jose State University, 1 Washington Square, San Jose, CA. 95192. Bhavya Bellannagari, Raghav Pramod Murthy, Shivani Kota, Hiral Mehta, IntelliScience Training Institute, 2139 S. 10th Street, San Jose, CA. 95122.

Dielectric barrier discharge (DBD) plasma jets are actively being used for medical applications. One area that needs further attention is rapid wound sterilization and healing when the wound is exposed to the DBD plasma jet [NCUR 2019]. The plasma jet inherently generates radicals like reactive oxygen species (ROS) and reactive nitrogen species (RNS) that act as active biological agents. Being a non-equilibrium discharge, these radicals are close to gas temperatures whereas the electron temperatures are higher (<=1ev). These radicals, when exposed to wound surface can deactivate bacteria and can enhance blood coagulation process causing rapid healing. In current work, a DBD plasma jet was examined for various radicals at different operating conditions. This was achieved by conducting emission spectroscopy on the ejecting plume. An optical fiber-based Ocean Optics spectrometer (UV-VIS) was used to capture spectroscopic signatures at various flow rates. The emission intensities of OH, OI, OII, N2+1, He and N2+2 lines were measured as a function of distance from the plasma nozzle exit at various operating conditions. The variation in the intensities of emission lines were noticed as the helium flow rate was increased from 9.5 lpm to 16.6 lpm at varying input voltages (4kV to 6kV). This was also confirmed by capturing the overall plasma illumination intensity at the operating conditions from the plasma images and by plotting pixel-by-pixel intensities using a Java based script. The higher intensities indicated high concentration of the radical species that plays a crucial role in mitigating bacteria on the wound surfaces. The research presented here is the first step in achieving the optimized operating condition where the gas flow rates and plasma input voltages are optimized for plasma jet temperatures with enough radicals to inactivate bacteria and to coagulate blood at a rapid speed. 

Keywords: Plasma-healing, Emission-Spectroscopy, Plasma-luminosity 

Additional Abstract Information

Presenters: Kathy Hoang, Bhavya Bellannagari, Raghav Murthy, Shivani Kota, Hiral Mehta

Institution: San Jose State University

Type: Poster

Subject: Mechanical & Industrial Engineering

Status: Approved

Time and Location

Session: Poster 8
Date/Time: Tue 5:00pm-6:00pm
Session Number: 5600