Hydrocyclone operation at the transition point rope/spray discharge

Numerical prediction of outlet velocity patterns in solid–liquid separators

“…Concha et al [6] points out that the best separation occurs near the formation of rope discharge. Similarly, Neesse et al [7] states on a broader note that a hydrocyclone achieves the best separation at a transitional discharge phase between roping and spraying. Many researchers have tried to control the operation of a hydrocyclone by using varying non-obtrusive experimental techniques.…”

“…Neesse et al [7] showed that the form of the underflow discharge can be used as an indication of the operating state of hydrocyclones. The angle is determined from the velocity components at the spigot and fluid properties.…”

“…The angle is determined from the velocity components at the spigot and fluid properties. Lacking the information from the threedimensional flow field, Neesse et al [7] derived the following equation:…”

“…Neesse et al [7] model assumes boundary conditions that simplify the equations from a three-to two-dimensional problem. For simplification, the flow conditions at the inlet assume an axial symmetrical flow.…”

“…The boundary conditions at the outlet assume that the effluent does not contact the air. Even with the simplifying assumptions for the method proposed by Neesse et al [7], which will be referred to throughout the paper as the Dueck method, the Dueck method was able to be used to control the operation of the hydrocyclone. The presented approach, which will be referred throughout the paper as the AFN method, is not limited to axisymmetrical flow.…”