Abstract
Adding plasmas to a flame has been shown to introduce high concentrations of charges, ions, and radicals to the said flame. This technique of adding plasma to a flame is called plasma-assisted combustion (PAC), and this addition has been shown to make a flame more stable and efficient. At the same time, PAC has also been shown to alter particle formation during combustion. Here, we investigate the effect of a high-frequency (∼21 kHz) alternating current (AC) corona discharge on particle formation and growth in a premixed flame, especially at the initial stages (with particle sizes below 10 nm). We first examined the mobility size distribution of ions generated from non-plasma combustion and corona-discharge-assisted combustion. The mobility size for positive ions does not change with the introduction of plasma. However, the negative ions change towards a larger size, likely due to different ion chemistry from plasma. We then introduced corona discharge with varying powers into the flame that contains titanium isopropoxide (TTIP) or tetraethyl orthosilicate (TEOS) and obtained the size distribution of the synthesized nanoparticles. For the precursor feed rates used in this study (TTIP: 9.6–48 mg h−1, TEOS: 60–100 mg h−1), we found that particle growth is suppressed by the corona discharge under relatively higher precursor feed rates (above ∼29 mg h−1 for TTIP and above ∼80 mg h−1 for TEOS). The mobility diameter is suppressed by up to 12 % for TTIP and by up to 20 % for TEOS. We further used different charging models to examine the impact of plasma on particle formation. In the case of higher precursor feed rates, the incipient particle concentration is high within the flame region. As higher number of charges accumulated on particles from negative-charge carriers (including electrons and negative ions) than positive ions, the particles are preferentially charged negative. Such preferential charging results in particle–particle repulsion, which suppresses coagulation particle growth. The findings of this study can guide nanoparticle synthesis and particulate matter control using PAC.
Recommended Citation
C. Bagya Ramesh et al., "Nascent Titanium-/silicon-containing Particle Formation In Corona-discharge-assisted Combustion," Aerosol Research, vol. 4, no. 1, pp. 265 - 277, Copernicus Publications, Jul 2026.
The definitive version is available at https://doi.org/10.5194/ar-4-265-2026
Department(s)
Mechanical and Aerospace Engineering
Publication Status
Open Access
International Standard Serial Number (ISSN)
2940-3391
Document Type
Article - Journal
Document Version
Final Version
File Type
text
Language(s)
English
Rights
© 2026 The Authors, All rights reserved.
Creative Commons Licensing
This work is licensed under a Creative Commons Attribution 4.0 License.
Publication Date
01 Jul 2026
Comments
Directorate for Engineering, Grant 2132655