TY - GEN
T1 - Optimization of Energy Distribution in Nanosecond-Pulsed High-Frequency Discharge Ignition
AU - Laso, Iker
AU - Shen, Si
AU - Lefkowitz, Joseph
N1 - Publisher Copyright: © 2022, American Institute of Aeronautics and Astronautics Inc. All rights reserved.
PY - 2022
Y1 - 2022
N2 - The effects of energy per pulse (Epp) on nanosecond-pulsed high-frequency discharge (NPHFD) ignition are parametrically investigated in methane-air mixtures at a nominal flow velocity of 4 m/s. Equivalence ratio is set to 0.6 and the inter-electrode gap distance is 2 mm. High-speed schlieren imaging was used to analyze ignition probabilities and kernel growth characteristics. Four levels of Epp were explored across a wide range of inter-pulse times (IPT): 1.5, 3.0, 4.5 and 6.7 mJ. In the fully-coupled regime, for a fixed number of pulses (N), Epp did not show any influence on ignition probability (PI). N, Epp and IPT have also shown to have little effects over kernel growth. Outside of the fully-coupled regime, PI drops to 0 for energy level of 1.5 mJ, whereas energy level of 6.7 mJ has PI = 1 for the entire range of IPT. For energy level of 3.0 and 4.5 mJ, a partially-coupled regime characterized by significant drops of PI is observed. Additionally, N were also varied with IPT and Epp while matching the total deposited energy (E) and the total discharge duration (T). IPT is found to be the driving parameter determining the inter-pulse coupling regimes and PI. Furthermore, single kernel analysis discovers the effect of destructive kernel interactions in the partially-coupled regime, which, against intuition, results in increasing minimum ignition power (MIP) for higher Epp. In conclusion, high frequency low energy discharge pulses are shown to have great potential being the optimal ignition method for NPHFD.
AB - The effects of energy per pulse (Epp) on nanosecond-pulsed high-frequency discharge (NPHFD) ignition are parametrically investigated in methane-air mixtures at a nominal flow velocity of 4 m/s. Equivalence ratio is set to 0.6 and the inter-electrode gap distance is 2 mm. High-speed schlieren imaging was used to analyze ignition probabilities and kernel growth characteristics. Four levels of Epp were explored across a wide range of inter-pulse times (IPT): 1.5, 3.0, 4.5 and 6.7 mJ. In the fully-coupled regime, for a fixed number of pulses (N), Epp did not show any influence on ignition probability (PI). N, Epp and IPT have also shown to have little effects over kernel growth. Outside of the fully-coupled regime, PI drops to 0 for energy level of 1.5 mJ, whereas energy level of 6.7 mJ has PI = 1 for the entire range of IPT. For energy level of 3.0 and 4.5 mJ, a partially-coupled regime characterized by significant drops of PI is observed. Additionally, N were also varied with IPT and Epp while matching the total deposited energy (E) and the total discharge duration (T). IPT is found to be the driving parameter determining the inter-pulse coupling regimes and PI. Furthermore, single kernel analysis discovers the effect of destructive kernel interactions in the partially-coupled regime, which, against intuition, results in increasing minimum ignition power (MIP) for higher Epp. In conclusion, high frequency low energy discharge pulses are shown to have great potential being the optimal ignition method for NPHFD.
KW - Inter-pulse coupling
KW - Minimum ignition power
KW - Nanosecond-pulsed high-frequency discharge
KW - Pulsed plasma ignition
UR - http://www.scopus.com/inward/record.url?scp=85123892879&partnerID=8YFLogxK
U2 - https://doi.org/10.2514/6.2022-2118
DO - https://doi.org/10.2514/6.2022-2118
M3 - منشور من مؤتمر
SN - 9781624106316
T3 - AIAA Science and Technology Forum and Exposition, AIAA SciTech Forum 2022
BT - AIAA SciTech Forum 2022
T2 - AIAA Science and Technology Forum and Exposition, AIAA SciTech Forum 2022
Y2 - 3 January 2022 through 7 January 2022
ER -