CPC G01N 1/2208 (2013.01) [G01N 1/2273 (2013.01); G01N 2001/2217 (2013.01)] | 18 Claims |
1. An apparatus for sampling particles transported in air, the apparatus comprising:
a nozzle having a first inlet configured to receive a pressurized gas and a second inlet configured to receive a pressurized liquid, the nozzle being configured to mix the pressurized liquid and the pressurized liquid to generate at an outlet of the nozzle a swirling jet of fog that comprises the gas and a plurality of liquid droplets dispersed in the gas, the plurality of liquid droplets comprising droplets of different volumes of 1 cubic micron or less, the nozzle being configured to produce the jet of fog in a way that results in the plurality of liquid droplets being shear stressed by the gas to cause the plurality of liquid droplets to be ellipsoidal, the jet of fog being generated by the nozzle to cause the particles transported in air surrounding the jet of fog to merge with the ellipsoidal liquid droplets; and
a sample collecting surface located in a downstream flow path of the swirling jet of fog, the sample collecting surface being located opposite the outlet of the nozzle, a straight line distance between the outlet of the nozzle and the sample collecting surface being sufficient for at least some of the ellipsoidal liquid droplets containing the particles to merge with one another inside the swirling jet of fog before impacting the sample collecting surface,
wherein there is no mechanical structure located between the swirling jet of fog and the surrounding air, nor between the outlet of the nozzle and the sample collecting surface.
|