Numerical analysis of the effect of surface recombination on N-atom in discharge and post-discharge region

In this paper, the effect of surface recombination on N-atom production is discussed through a one-dimensional simulation of Townsend dielectric barrier discharge in pure N2 based on a fluid model. By comparison of the experimental results, the recommended value of the sticking coefficient of N–N surface recombination is 0.5–1. The spatial-temporal distribution of N-atom of simulation results in discharge and post-discharge agree with experimental results. When the sticking coefficient is 0.5, the primary active species include N, N2(A), and N2(a0). N4 þ is the densest positive ion, which can reach 4.77 109 cm3. N-atom can reach the saturation level within about 30 ms. The highest number density is 3.14 1014 cm3 at the position 0.25 mm away from the surface. The numerical simulation results are very consistent with the experimental results. The contribution of surface recombination and three-body recombination for the decay of N-atom are roughly equal in the post-discharge region.