Liquid Nebulizer / Aerosol Generators
VDI 3491

ATM 241 - Very high output by multiple nozzles

The Aerosol Generator ATM 241 produces droplet aerosols with known properties according to the guideline VDI 3491. The designs and technical solutions warrant highly constant particle size distribution as well as particle concentration with high reproducibility and a high aerosol output.
The generators of series ATM 241 enable to atomize various liquids, for example PAO (Emery 3004), DEHS, PSL-suspensions, and saline solutions.


  • Polydisperse aerosol mainly below 1 µm
  • Excellent constant particle size distribution
  • Defined and high particle number concentration
  • By varying of nozzle pressure and the number of switched-on nozzles one can adjust both particle production rate and within narrow limits the particle size distribution
  • Generation of tracer particles
  • Verifying measurements in very large clean rooms
  • Test of HEPA and ULPA filter media


  • Test aerosol liquid DEHS
    (80 ml, 0,5 l, 1 l, 5 l or 20 l)
  • Further aerosol liquids e.g. PAO (Emery 3004) on request

Heart of the generator is new, patented ring slit nozzle, which allows based on its geometry the generation of finest aerosols.
The figure shows the operation principle schematically. Compressed air is blown through a 100 µm thin ring slit into the liquid to be nebulized. Because of high air velocities at the circumjacent breaking edge, the resulting under pressure drags the liquid along. Shear forces acting between air jet and the liquid at the circumference of this so-called ring slit nozzle form the droplet aerosol. Coarse droplets are prevented from leaving the liquid through inertial effects inside the produced small bubbles.


ATM 241

Particle number
concentration (DEHS):


Compressed air supply:

max. 8 bar (115 psi)

Flow rate:

5…70 m3/h

Mass flow rate (DEHS)*:

max. 240 g/h

Feeding volumen:

4.7 (min)…8 l (max)


two-component jet


4 Nozzles (individually switchable)


480  x 250  x 220


6.2 kg


*Fluids: DEHS, PAO (Emery 3004), Saline solutions, Latex suspensions

Aerosol specfication for DEHS


Particle size: Concentration
Total: >108#/cm3
0.2 µm: 2×107#/cm3
0.5 µm: 5×105#/cm3
1.0 µm: 1×105#/cm3
0,3 – 0,5 µm: 1.5×107#/cm3
0.5 – 1.0 µm: 8×106#/cm3
Median value: 0.1 .. 0.5 µm