A donut-shape distribution of OH radicals in atmospheric pressure plasma jets.

Autor: Yuanfu Yue, Fan Wu, He Cheng, Yubin Xian, Dawei Liu, Xinpei Lu, Xuekai Pei
Předmět:
Zdroj: Journal of Applied Physics; 2017, Vol. 121 Issue 3, p1-9, 9p, 8 Diagrams, 3 Graphs
Abstrakt: In this work, OH radicals that have a donut-shape distribution in the room-temperature atmospheric-pressure plasma jet are investigated using the laser-induced fluorescence method. The plasma jet driven by a pulse power supply is operated under two conditions: without the ground electrode and with the ground electrode. It is found that the OH radicals distribute as a donut-shape for the first several pulses under both two conditions. With more pulses applied, the donut-shape disappears and OH radicals distribute as a solid disk. Detailed investigations show that the total OH radicals in the plasma plume are formed from two parts. One part is generated by the plasma plume outside the tube with a structure of a donut-shape. The other part is generated by the plasma inside the tube with a structure of a solid disk, which can be transported to the downstream with gas stream and leads to the disappearance of the donut-shape in the plasma plum. Moreover, when the ground electrode is applied, higher intensity of OH is obtained as well as OH donut-shape distribution is observed with dehumidified working gas. It may be due to the higher electron density and its donut-shape distribution in the effluent according to the simulations and experimental results. Published by AIP Publishing. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index