Solid Nucleation Mode Engine Exhaust Particles Detection at High Temperatures with an Advanced Half Mini DMA
Diesel and gasoline direct injection engines emit nucleation mode particles either under special conditions or as part of their size distribution, respectively. Currently, European legislation excludes nucleation mode particles as particle number vehicle emission measurements are limited down to 23 nm. The rationale behind such cut-off size is based on the avoidance of significant uncertainties created during sampling and measuring sub-23 nm solid particles. However, the sub-23 nm particles draw high attention since a large fraction of particles emitted by modern vehicles lies in this size range. In this study we investigate the possibility of accurate nucleation mode particles detection by using the Advanced Half-Mini Differential Mobility Analyzer (HM-DMA). The Advanced HM-DMA system is able to classify aerosol particles in the mobility size range 4 – 30 nm with high resolution and fast spectrum acquisition that can accommodate a hot sample flow up to 200°C.