Machine Parts

In a real impactor , the nozzle flow impacts on a flat plate placed at right angle to the nozzle flow and flows  radially outwards on the plate. Hence, the flow field is constant in real impactor provided the flow rate Q 1   through the nozzle is constant, whereas in a virtual impactor this is not the case. Here keeping the total flow  rate Q 1 through nozzle constant, the minor flow rate Q m   through collection prove can be changed by  changing the major flow rate Q 2 through the vacuum pump. Hence, in virtual impactor , the effective velocity responsible for pushing the particles into the minor flow is a  difference of velocities (V 1 -V 2 )   , Where   V 1    and V 2     are the velocities corresponding to the nozzle flow  rate and major flow rate. The experimental analysis has been done in set II   in accordance with the methodology described below. Stokes number for a virtual impactir is given by: Stk=   Ʈ (V 1 -V 2 )    

Changing the size of narrowly distributed aerosols: The size of narrowly distributed aerosols generated in the aerosols generator can be  controlled by controlling solution concentration (C c ) . , Minor flow rate (Q m )   and total flow rate (Q 1 ) .  Effect of change in solution concentration: The size of aerosols with narrow size distribution can be varied by changing the concentration  of liquid solution according to the relation. C c = V p /V d = d p 3 /d d 3 Where       C c = Solution concentration    V p = Volume of solute from which final particles are formed, V d = Volume of solvent  d p = Diameter of particle and d d = Diameter of droplet We know d d   because it is the cut off diameter of droplets in the virtual impactor . Forconstant  flow rate through the virtual impactor, the cut off diameter , d d , in the virtual impactor is  always constant. Hnece, depending on the final particles diameters , d