Venacontra Diluting Aerosol Sampler (VC-DAS) is a combination of the Venacontra Porous Tube Diluter and the Venacontra Ejector Diluter providing a flexible and reliable sampling system which operates well with process gases with very high particle concentrations, such as combustion or nanoparticle synthesis. It offers wide range of dilution ratios with stable sampling flow.
In the Venacontra Diluting Aerosol Sampler the sample is first drawn through a cyclone, to remove coarse particles from the sample stream and then diluted in two steps, usually with filtrated and dried air. The first dilution is carried out in a porous tube diluter and the second dilution in an ejector diluter. The diluted sample can be divided between different analyzers and particle sample collection systems. In combustion processes a partial flow of the diluted sample is taken into a CO2 -analyzer to determine the dilution ratio of the sampling system.
The sampling system can be assembled either as an in-stack-cyclone configuration (see Figure 1a) or out-stack-cyclone configuration (see Figure 1b). When using out-stack configuration, the cyclone and other possible sampling lines must be heated and thermally well insulated to avoid cooling of the sample before dilution.
Diluting sampling system with in-stack cyclone configuration.
Diluting sampling system with out-stack cyclone configuration.