Hydrodynamics rotor-stator

Vibration peaks at specific speeds/high axial vibration is often present. Siib-harmomc Usually occurs as a result of loose components or as a result of aerodynamic or hydrodynamic excitations areas to be investigated for coiTection are seals, thrust clearance, couplings, and rotor/stator clearance... 

Rotor-stator systems consist of a rotating tool (rotor) and a coaxially fixed wall (stator). The suspension is brought into the thin annular gap between rotor and stator, where the particles experience intensive hydrodynamic stress. Two types of rotor-stator systems can be distinguished (Fig. 5.2). 

Figure 8-1 Couette rotor-stator geometry, single-stage design (a) simple Couette (b) toothed rotor-stator (c) schematic representation of hydrodynamics (d) commercial...

There are two basic designs of floatation cells mechanical and pneumatic. Mechanical cells are the most common design and generally use a stator with an overhead-driven rotor to circulate the slurry medium (pulp) and also to provide air dispersion and bubble shear see Figure 4.11. Aeration may be self-induced or introduced from an external air source, and the froth is removed using peripheral launders. Pneumatic cells make use of aeration and hydrodynamics to circulate and suspend the pulp as well as achieving froth separation. 

Detailed hydrodynamic studies have been performed for pump-fed in-line mixers with rotors and stators comprised of teeth with slots between them. LeClair (1995) reported an early attempt for a Kady mixer. Although the simulation was quite simplistic and considered only a small section with assumed perfect symmetry, the results revealed a complex circulation pattern in the stator slot. 

VHBI hydrodynamic brakes. These brakes are characterized by performance with small overall dimensions as a result of the inclined blading of the rotor and stator. The hydrodynamic brake is effective in only one direction of rotation. 

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