Initial sample liquid volume maintained by on-line liquid loss compensation even when relative humidity or temperature changes during sampling.

Drawing ① When the fan is initially actuated, air enters tangentially into a «cycloning cup» at the base of the device, setting up high speed cycloning airflow pattern in it.4 to 5 ml of water is simultaneously injected from the «water tank» using peristaltic pump P2.
Drawing ② A sample water pool initially forms at the bottom of the cyclonic cup.
The rapidity rotating air mass in the «cycloning cup» initially distributes sample water as a thick film on its interlor surfaces.
Some water is also driven into a smaller diameter «stripping column» situated immediately above the cyclonic cup as airflow increases towards its nominal value.
Drawing ③ Air flows from the cyclonic cup into the stripping column as a rapidly rotating air mass as airflow approaches its nominal value. A water film forms over the stripping column’s interior surface due to air shear and a favorable geometry.
Sample water then flows upward into a large diameter «cistern» section.
Air shear there causes sample water to flow outwardly, forming a rotating fluid ring.
Drawing ④ Water flows back downward to the cyclonic cup via a ‘liquid return tube’ driven by gravity and a low pressure region in the cyclonic cup. Particulates are captured by the water film that now covers the critical interior surfaces. At
nominal airflow, the water circulation process repeats several times per minute. Water is added as needed to maintain a constant sample volume. All or part of the circulating water sample may be withdrawn at any time using peristaltic pump P1.
Sass 2300 patented technology allows automatic compensation of evaporation loss, adaptating to unforeseen relative humidity or temperature changes during sampling