Volatility Differential Mobility Particle Sizer (V - DMPS) / Volatility Tandem Differential Mobility Analyzer (V-TDMA)
Purpose of Participation
- Aerosol mixing state and measurements of aerosol thermal stability for temperatures up to 350°C in two different modes: 1) Size segregated integral thermal stability (V-DMPS) 2) Size segregated stability addressing volatile volume/mass fraction (V-TDMA)
Instrument description
V-DMPS: Near monodisperse aerosol selected in first DMA pass through the heater and the number of particles remaining after heating is than counted by CPC. Comparing number density prior and after heating the volatile fraction and mixing state of aerosol can be addressed.
V-TDMA: Similar to V-DMPS, but instead just counting particles after heating, second DMA is used to measure size distribution of the near monodisperse aerosol after heating, to obtain information about mixing state of particles and closer estimate of volatile/non-volatile fractions at respective temperature
| Species | Aerosols |
| Method | Aerosol thermal stability and mixing state |
| Quantity primary | Size segregated aerosol mixing state; size segregated aerosol volatile/non-volatile fraction |
| Quantity secondary | Aerosol volatile mass/volume fraction |
| Measurement range | 0.003 - 0.26 µm |
| Altitude range | NA |
| Vertical resolution | NA |
| Temporal resolution | >= 5 minute for V-DMPS; 30 minutes for V-TDMA |
| Operation | continou operation between 25 May and 15 June |
| Precision | Depends on aerosol concentration |
| Preliminary data | V-DMPS: 3 months; V-TDMA: 6 months |
| Final data | one year |
Specific remarks
- Ambient p and T from POLAR 4 basic instrumentation are required to derive correct ambient aerosol size distribution
- Custom made instrument
- Time resolution depends also on aerosol number density