The Multiple Monodisperse Outlet Differential Mobility Analyzer: Derivation of Its Transfer Function and Resolution

Figures & data

FIG. 1 Schematic diagram of the MMO-DMA showing (a) the flows associated with each monodisperse-particle outlet, (b) the fluid and electric field streamlines, and (c) the particle streamlines. Key: Q_a is the polydisperse aerosol inlet flow rate, Q_sh is the sheath air flow rate,

is the sample flow rate of the ith monodisperse-particle outlet,

is the excess flow rate after the ith monodisperse-particle outlet,

is the sheath air flow rate before the ith monodisperse-particle outlet, and R ₁ and R ₂ are the outer and the inner radii of the MMO-DMA, respectively.

FIG. 2 Schematic diagram of the MMO-DMA showing (a) the individual segments of the column, and the associated diffusional broadening parameters for the particles exiting through the ith outlet (note that the total broadening is the sum of the spreading parameters in each segment given by Equation (39)), and (b) the integration path along the particle streamline with the associated steps over each monodisperse-particle outlet. Key: ω _i,j,u and ω _i,j,d are the dimensionless radial positions of a particle classified through the ith outlet when it enters and exits, respectively, the jth segment, and

is the total flow rate at the jth segment.