APPARATUS AND PROCESS FOR PRODUCING ACKNOWLEDGED AIR FLOW AND THE USE OF SUCH APPARATUS IN MEASURING PARTICLE CONCENTRATION IN ACKNOWLEDGED AIR FLOW

摘要

The present invention discloses an apparatus for generating an identified flow (Q). The device comprises a first passage (2) for allowing air to flow, at least in part, in an essentially perpendicular direction, i.e. in a direction aligned with the gravity direction, a second passage (2) arranged in the first passage (5) for generating unipolar ions (8) carried in the air in the first passage (2), an air flow (Q) through the first passage (2) by being arranged to generate a temperature difference in the first passage (2) (12, 13) having an output which is a function of the concentration of the air-borne charge, a parameter which affects the output of the sensing element (12, 13) , And a switching or regulating operation by the switching or regulating means (17) is performed on the basis of the response time generated for the output of the sensing element (12, 13) Quot; The present invention discloses the use of an apparatus (1) for determining ultrafine particle concentration. The present invention also discloses a method for generating an identified flow.