Tangential Gas Velocity

Early theoretical treatments of cyclone flow patterns (Lissman 1930; Rosin, Rammler, and Intelman 1932) described the relationship between the tangential gas velocity Vt and the distance r from the cyclone axis as:

The vortex exponent n is +1 for an ideal liquid and — 1 for rotation as a solid body, while the usual range for n is from 0.5 to 0.9 (Ter Linden 1949; Shepherd and Lapple 1939; First 1950).

Equation 5.16(4) implies that tangential velocity increases from the walls to the cyclone axis where it reaches infinity. Actually, in the outer vortex, tangential velocity increases with decreasing radius to reach a maximum at the radius of the central core. In the inner vortex, the tangential velocity decreases with decreasing radius. Figure 5.16.3 shows Iozia and Leith's (1989) anemometer measurements of tangential velocity. Measurements by Ter Linden (1949) show similar velocity profiles.

0 0

Post a comment