ElectricOIL discharge and post-discharge kinetics experiments and modeling

摘要

Laser oscillation at 1315 nm on the I(~2P_(1/2)→ I(~2P_(3/2)) transition of atomic iodine has been obtained by a near resonant energy transfer from O_2((a~1Δ) produced using a low-pressure oxygen/heliumitric-oxide discharge. In the electric discharge oxygen-iodine laser (ElectricOIL) the discharge production of atomic oxygen, ozone, and other excited species adds levels of complexity to the singlet oxygen generator (SOG) kinetics which are not encountered in a classic purely chemical O_2(a~1 Δ) generation system. The advanced model BLAZE-IV has been introduced in order to study the energy-transfer laser system dynamics and kinetics. Levels of singlet oxygen, oxygen atoms and ozone are measured experimentally and compared with calculations. The new BLAZE-IV model is in reasonable agreement with O_3, O_2(b~1∑), and O atom, and gas temperature measurements, but is under-predicting the increase in O_2(a~1Δ) concentration resulting from the presence of NO in the discharge. A key conclusion is that the removal of oxygen atoms by NO_X species leads to a significant increase in O_2(a~1 Δ) concentrations downstream of the discharge in part via a recycling process, however there are still some important processes related to the NO_X discharge kinetics that are missing from the present modeling. Further, the removal of oxygen atoms dramatically inhibits the production of ozone in the downstream kinetics.