For a 90 degree radius bend, solids velocity at the exit of the
bend Vp2 is 0.8 times the solids velocity at the inlet of the bend
Vp1. The factor "0.8" is a typical value but it ranges from 0.6 to
0.9 depending upon the properties of the solids. For bends that
are less than 90 degrees, the exit velocity Vp2 is