Low Reynolds Numbers Similitude Law for Particles of Finite Diameter

DIFFUSION AT LOW REYNOLDS NUMBERS SIMILITUDE LAW FOR PARTICLES OF FINITE DIAMETER 

For particles of finite diameter, the interception effect becomes important. A useful similitude law that takes both diffusion and interception into account can be derived as follows (Friedlander, 1967) It is assumed that the concentration boundary layer is thin and falls 

Taking R = apfa, only one dimensionless group that we take for convenience to be 

This is the similitude law for the diffusion of particles of finite diameter but with R 1 in low-speed Rows. For fixed Rc, the group should be a single-valued function 

Experimental data collected for different particle and cylinder diameters and gas velocities and viscosities should all fall on the same curve when plotted in the form of (3.37). 

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