A concentrator for increasing the particle concentration in an aerosol flow, characterized by a sculptured acceleration plate with a number of slit-shaped entry openings adapted to receive a first aerosol volume flow and having a first cumulative cross-sectional size, and a number of slit-shaped acceleration plate exit openings adapted to release the first aerosol volume flow and having a second cumulative cross-sectional size that is smaller than the first cumulative cross-sectional size; a sculptured deceleration plate with a number of slit-shaped deceleration plate entry openings adapted to receive a second aerosol volume flow of high particle concentration and having a third cumulative cross-sectional size, and a number of slit-shaped deceleration plate exit openings adapted to release the second aerosol volume flow and having a fourth cumulative cross-sectional size that is larger than the third cumulative cross-sectional size; wherein sculptured acceleration channels extend between the acceleration plate entry openings and the acceleration plate exit openings and sculptured deceleration channels extend between the deceleration plate entry openings and the deceleration plate exit openings; the acceleration plate exit openings are spaced from a base surface on an exit side of the acceleration plate and the sculptured deceleration channel entry openings are spaced from a base surface on an entry side of the deceleration plate; a gap is provided between the acceleration plate base surface and the deceleration plate base surface, the gap being adapted to release a third volume flow of low particle concentration; and the acceleration plate exit openings overlap substantially with the deceleration plate entry openings; characterized by the slit-shaped entry openings, acceleration plate exit openings, deceleration plate entry openings and deceleration plate exit openings have large length/width ratios and have lengths radially extending from a location closer to a center of the respective acceleration and deceleration plates (6110, 7120) in radial direction to a location closer to an outer periphery of the respective acceleration plate and deceleration plate; and comprise openings of at least two different lengths, wherein a first group of longer slit-shaped openings extend from a location close to the center to a location closer to the outer periphery of the acceleration plate and deceleration plate while a second group of shorter slit-shaped openings extend from a location spaced from the center to a location closer to the outer periphery. a sculptured acceleration plate with a number of slit-shaped entry openings adapted to receive a first aerosol volume flow and having a first cumulative cross-sectional size, and a number of slit-shaped acceleration plate exit openings adapted to release the first aerosol volume flow and having a second cumulative cross-sectional size that is smaller than the first cumulative cross-sectional size; a sculptured deceleration plate with a number of slit-shaped deceleration plate entry openings adapted to receive a second aerosol volume flow of high particle concentration and having a third cumulative cross-sectional size, and a number of slit-shaped deceleration plate exit openings adapted to release the second aerosol volume flow and having a fourth cumulative cross-sectional size that is larger than the third cumulative cross-sectional size; wherein sculptured acceleration channels extend between the acceleration plate entry openings and the acceleration plate exit openings and sculptured deceleration channels extend between the deceleration plate entry openings and the deceleration plate exit openings; the acceleration plate exit openings are spaced from a base surface on an exit side of the acceleration plate and the sculptured deceleration channel entry openings are spaced from a base surface on an entry side of the deceleration plate; a gap is provided between the acceleration plate base surface and the deceleration plate base surface, the gap being adapted to release a third volume flow of low particle concentration; and the acceleration plate exit openings overlap substantially with the deceleration plate entry openings; characterized by the slit-shaped entry openings, acceleration plate exit openings, deceleration plate entry openings and deceleration plate exit openings have large length/width ratios and have lengths radially extending from a location closer to a center of the respective acceleration and deceleration plates (6110, 7120) in radial direction to a location closer to an outer periphery of the respective acceleration plate and deceleration plate; and comprise openings of at least two different lengths, wherein a first group of longer slit-shaped openings extend from a location close to the center to a location closer to the outer periphery of the acceleration plate and deceleration plate while a second group of shorter slit-shaped openings extend from a location spaced from the center to a location closer to the outer periphery.