DIFFER
DIFFER Publication

A Modified Fokker–Planck Approach for a Complete Description of Vibrational Kinetics in a N2 Plasma Chemistry Model

Author
Abstract

The Fokker–Planck (FP) approach for the description of vibrational kinetics is extended in order to include multiquanta transitions and time dependent solutions. Due to the importance of vibrational ladder climbing for the optimization of plasma-assisted nitrogen fixation, nitrogen is used as a test case with a comprehensive set of elementary processes affecting the vibrational distribution function (VDF). The inclusion of the vibrational energy equation is shown to be the best way to model transient conditions in a plasma reactor using the FP approach. Results are benchmarked against results from the widely employed state-to-state (STS) approach for a wide parameters range. STS and FP solutions agree within ∼10% for the lowest vibrational levels, while time dependent VDFs are in agreement with the STS solution within a ∼ 5% error. Using the FP approach offers the possibility to parametrize drift and diffusion coefficients in energy space as a function of vibrational and gas temperature, providing intuitive and immediate insights into energy transport within the vibrational manifold.

Year of Publication
2023
Journal
Journal of Physical Chemistry A
Volume
127
Issue
1
Number of Pages
261–275
DOI
10.1021/acs.jpca.2c06042
PId
d6a9b0fb027d6cad8df2a0728140376f
Alternate Journal
J. Phys. Chem. A
Label
OA
Journal Article
Download citation