The critical velocity of rebound determined for sub-micron silver particles with a variable nozzle area impactor
Research output: Contribution to journal › Article › Scientific › peer-review
|Number of pages||12|
|Journal||Journal of Aerosol Science|
|Publication status||Published - 1 Aug 2015|
|Publication type||A1 Journal article-refereed|
The critical velocity of rebound was determined for spherical silver aerosol particles in the size range of 20-1000. nm. A novel instrument, a variable nozzle area impactor, was especially designed for measuring the particle-surface interaction as a function of the particle impact velocity. The experimental results were combined with a numerical model in order to obtain the impact velocities. The experiments were carried out using a plain aluminum collection substrate in the impactor. Our results show that the critical velocity of rebound decreases from 14 to 0.022. m/s as the particle size increases from 20 to 1000. nm. Furthermore, the critical velocity was found to be proportional to the power of -1.6 of the particle size, instead of the theoretical inverse proportionality. This result is in line with the previous studies for micron-sized particles. In the nanoparticle size range, the obtained values are approximately 3-10 times greater than the recent literature values. This discrepancy can most likely be explained by the different surface materials. All in all, our results give valuable information about the particle-surface interactions in the sub-micron size range.
- Silver nanoparticle, Rebound, Critical velocity, Low-pressure impactor, LOW-PRESSURE IMPACTOR, ORGANIC AEROSOL-PARTICLES, NANOPARTICLES, BOUNCE, MONODISPERSE, FRAGMENTATION, RESOLUTION, SURFACES, CAPTURE, DENSITY