Session: 11-15-01: Fluid Problems in Energy Systems

Paper Number: 166040

Lifetime Evaluation of Surface Dielectric Barrier Discharge Plasma Actuators for Green Combustion Application 

More than ever, designing the so-called novel green combustion systems is the major goal of the academic and industrial worlds. Despite the ongoing attempt to shift towards renewable energy sources, fossil fuels remain the dominant source of global energy production. Consequently, high-efficiency combustion systems are sought to reduce the overall environmental impact of fossil fuels (e.g., greenhouse gas emission, global warming, air pollution, ocean acidification) and simultaneously comply cost-effectively with international environmental regulations. Recently, plasma has been vastly applied to fuel reforming in engines, burners, and reactors. Specifically, single-layered dielectric barrier discharge plasma actuators have been studied to improve combustion reactions through enhanced fuel decomposition, ionic wind generation, and thermal and kinematic effects. However, experimental studies in high-temperature regimes providing an understanding of the SDBD plasma actuator behavior are lacking in the literature.

Therefore, in the current work, six SDBD plasma actuators with different dielectric thicknesses of 1.0 mm, 1.5 mm, and 2.0 mm were studied at room (20 ºC) and high (120 ºC) temperatures throughout four hours. The major goal of the study is to evaluate the degradation process of the SDBD dielectric layer due to both long exposure and temperature (using a hot plate) effects. Specifically, power consumption, charge, and capacitance magnitudes were computed to analyze their variation over time and to quantify the actuators' degradation rate. Moreover, macroscopic images of the DBD plasma actuators were taken to show the geometric variations induced by both plasma discharge and hot plate temperature.

Preliminary results showed macroscopic geometric modifications due to both long exposure to plasma discharge and induced high temperatures (for the three actuators studied on the 120 ºC hot plate). Specifically, the 1.0 mm actuator burned on the hot plate due to arc formation after long operation. Nevertheless, microscopic modifications were analyzed with a digital microscope. Darkened areas were noted in all six actuators, due to the gradual burning of the electrode and dielectric layer, near and on the plasma discharge region, respectively.

Computed by the Electrical Current Method, power consumption oscillated during the test cases run. However, the three actuators studied at room temperature (20 ºC) presented lower standard deviation values than the other three actuators studied at high temperature (120 ºC). This phenomenon is believed to originate due to the heating of the hot plate, which directly impacts the stability of the DBD plasma actuator through material degradation. Additionally, average capacitance and average charges computed by the Electrical Charge Method showed concordant behaviors.

Most studies in the literature focus on modelling and simulation for combustion enhancement through the air/fuel mixture optimization via SDBD plasma actuators. This study focuses on raising concerns and pointing out future material-wise directions to pursue to enable experimental application of the solutions found so far by different authors. 

Presenting Author: Kateryna Shvydyuk University of Beira Interior

Presenting Author Biography: Kateryna Shvydyuk has received an integrated master's degree in Aeronautical Engineering from the University of Beira Interior. She participated in complementary courses (ESA Academy) and competitions (ActInSpace Hackaton and Coimbra Space Summer School) during her studies. She is the winner of the First Honorable Mention in the Best Thesis Award 2023 competition in the Materials Science field in Portugal. While finishing her master's and being a Visiting Researcher at the Centre for Aerospace Science and Technologies (C-MAST), she worked as a Systems Engineer for the aerospace and naval defense-related industries. Nowadays, she is a PhD student in Mechanical Engineering.

Authors:

Kateryna O. Shvydyuk University of Beira Interior
Leonardo A. Mbanguine University of Beira Interior
José C. Páscoa University of Beira Interior
Frederico F. Rodrigues University of Beira Interior