Two-dimensional imaging of NO density during NOx removal by LIF technique in a corona radical shower reactor

Two-dimensional NO concentration distribution was studied by using a planar laser induced fluorescence (PLIF) technique in a corona radical shower system during NOx removal. In order to monitor the ground-state NO molecules, NO transition at 226 nm was used. The corona radical shower reactor consists of a nozzle-to-plate electrode system, having an electrode gap of 50 mm. Stable DC streamer corona discharge was generated at atmospheric pressure and laser pulses in the form of the sheet were shot between the gap during the discharge. LIP signal emitted at 90 degree to the laser sheet was imaged onto a gated ICCD camera and the two-dimensional LIF images around the streamer corona region were recorded under steady-state DC corona condition in NOx removal. The obtained results showed that the density of NO molecule decreased not only in the plasma region formed by the corona streamers but also in both the upstream and downstream regions of the reactor. This information is important for optimizing the corona radical shower reactors.