Effects of chamber configuration on the nanoparticle output of spark discharge generators: A combined CFD, particle tracing, and experimental study

Spark discharge generators (SDGs) are versatile tools for producing nanoparticles (NPs) with tailored properties. This study combines Computational Fluid Dynamics (CFD) and Particle Tracing (PT) simulations in COMSOL Multiphysics® with experimental data to investigate the effect of various chamber configurations, including inlet/outlet positioning and chamber volume on the NP output. Five geometries were tested, with results showing that shorter inlet-to-outlet distances increase the gas velocity at the electrode gap, reduce particle residence time, and lead to higher particle yields. The experimental results were consistent with the simulations after normalization to the product of spark energy and frequency, indicating only a minor dependence of output concentration on chamber volume, given that the residence time does not exceed the sparking period. Our results highlight the effectiveness of combined CFD-PT simulations in predicting and optimizing SDG performance. • Chamber configuration influences nanoparticle transport efficiency in spark discharge generators. • Shorter inlet-to-outlet distances increase flow velocity at the electrode gap and reduce particle residence time. • Fluid dynamics and particle-tracing simulations accurately predict normalized experimental particle output trends if the particle residence time is not longer than the sparking period. • Combined CFD-PT modeling provides a reliable framework for optimizing aerosol nanoparticle generators.