Investigation of the effect of nozzle shape on supersonic/hypersonic impactors designed for size discrimination of nanoparticles

- Different nozzle configurations were investigated for supersonic/hypersonic impactors.
- Using a cap as a focuser in the nozzle could decrease the cut-off size of impactor.
- Cone-cap nozzle performed better than disk-cap nozzle.
- Laval nozzle could have a small cut-off size if the nozzle was close to the impactor plate.