Impact of a DBD Plasma Jet Flow Rates on Pathogen Mitigation

Michael Banga, Sohail Zaidi, Department of Mechanical Engineering, San Jose State University, 1 Washington Square, San Jose, CA 95192 Bhavya Bellannagari, Khadijah Atthar, Neha Suri, Vedmanvitha Ketireddy, Alaap Rag, IntelliScience Traning Institute, 2139 South 10th Street, San Jose, CA 95112

As an ongoing research activity at San Jose State University, a non-equilibrium dielectric barrier discharge (DBD) plasma jet device was tested for pathogen mitigation. The design of the plasma jet device was based on a patent (US9433,071B2-Zaidi IntelliScience) and went through a series of design alterations. In this work, a third-generation design was used. This design can change the exit dielectric tube to vary its diameter from 5 mm to 20 mm. The nature of flow (turbulent/laminar), flow rates, choice of working gas (Helium/Argon) for various operating conditions generated plasma that was characterized for plume lengths, plume temperatures as a function of plasma jet exit diameters, and applied voltages. Plasma jet temperatures at various distances from the plasma jet exit were also measured as a function of time. A K-type thermocouple was used to measure the temperatures. The thermocouple was calibrated using an isothermal medium at a near steady-state condition. Reynolds number which estimated the laminar or turbulent nature of flow was calculated for various flow conditions that were used to understand the impact of flow conditions on bacteria. In this work, bacteria samples (Bacillus Subtilis/Ecoli k-12) were obtained from an outside source. The bacteria were swabbed into a petri dish with agar and were kept at a constant temperature of 37◦C. This investigation may lead to the optimization of the plasma properties and operating conditions for effective bacteria inactivation. In summary, the work presented here will include design analysis of the third generation of the plasma jet device, characterization of the plasma plume at various operating conditions with helium and argon as the working gases, and bacteria inactivation at various plasma operating conditions with both helium and argon. 

Keywords: Helium/Argon, Plasma, Biomedical-Applications, Bacteria-Inactivation

Additional Abstract Information

Presenters: Michael Banga, Bhavya Bellannagari, Khadijah Atthar, Neha Suri, Vedmanvitha Ketireddy, Alaap Rag

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: 5601