Cunningham correction factor density

Fig. 4. Terminal velocities in air of spherical particles of different densities settling at 21°C under the action of gravity. Numbers on curves represent tme (not bulk or apparent) specific gravity of particles relative to water at 4°C. Stokes-Cunningham correction factor is included for settling of fine particles.

FIG. 14-115 Experimental collection efficiencies of rectangular impactors. C is the Stokes-Cunningham correction factor pp, particle density, g/cm3 Ug, superficial gas velocity, approaching the impactor openings, cm/s and g, gas viscosity, P. [Calvert, Yung, and Leung, NTIS Publ. PB-248050 based on Mercer and Chow, J. Coll. Interface Sci., 27, 75 (1968).]... 

Here APgas is the gas pressure drop across the Venturi in cm H2O, Pp is the particle density in g/cm Pg is the gas viscosity in poise, P( is the liquid density in g/cm, dp is the particle diameter in micron, Cc is the Cunningham correction factor and / is an experimental coefficient varying between 0.1 and 0.4. 

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