Journal of aerosol science A technical note effect of flow geometry on the nanoparticle output of a spark discharge generator

Abstract Spark discharge nanoparticle generators (SDGs) employ the method of spark ablation to generate nanoparticles (NPs) in the gas phase. The material plume ablated from two bulk electrodes is quenched and carried away by a controlled gas flow. The electrical circuit needed to maintain sparking and the gas/aerosol handling are usually rather simple to implement, therefore many different SDG designs exist in the literature. Since the carrier gas plays an important role in particle formation, the actual flow field inside the SDG chamber might also affect the properties of the generated particles. In this technical note we systematically investigate the size distribution of Ag NPs in various flow conditions. Size distribution measurements are used to compare cross-, coaxial-, and mixed flow geometries at different gas inlet to aerosol outlet distances, flow directions and volumetric flow rates and complemented with steady flow field simulations. The mechanisms behind the results are also briefly discussed.