The Final Rising or Falling Velocity of Single Particles

1 The Final Rising or Falling Velocity of Single Particles 

The drag coefficient is a function of the Reynolds number with the particle diameter J as the characteristic length  

With respect to practical applications it is reasonable to plot the dimensionless velocity according to 

This law is valid for solid spherical particles up to Re 1. The curve rigid spheres can be used to calculate the final rising or sinking velocity of solid spheres for Re I. 

Fluid particles are approximately rigid for rjc/Vd however, as a rule, an inner circulation takes place if no detergents are adsorbed at the interface. The law according to Hadamard and Rybczynski (Hadamard 1911 Rybczynski 1911) according to the straight line 2 in Fig. 3.6-3 describes the velocity  

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