Measurement of Particle Impact Frequencies and Velocities on Impeller Blades in a Mixing Tank

Erosive wear of various stainless steel grades used as impeller blade materials in high temperature aqueous slurry

“…In this region, weak signs of wear localization were seen compared to the inner upper corner. For a pitched-blade impeller, Kee et al [15] observed the highest wear intensity in the inner edge of the blade but in the lower corner. This demonstrates that the location of the most intense wear is highly dependent on the geometry of the test apparatus.…”

“…The flow fields generated during mixing and erosion of the impeller blades depend on the geometry of the system [15,16]. It is well established that a trailing vortex is typically generated behind a moving impeller blade [17][18][19][20], which causes turbulence leading to extensive localized wear [13,14].…”

Review of Visualization of Flow and Dispersion States of Slurry System Fluids in Stirred Vessels

“…The critical speed of suspension Nc and power Pc corresponding to Nc (N js ) were observed to vary independently with both, D and T, to give two correlations for each of the variables, Nc and Pc; one for the close proximity impeller operation, where both Nc and Pc remained invariant with off-bottom impeller clearance, and the second for the region where Nc and Pc were affected significantly by the impeller position. 1.1.2 Particle-Blade Impact Velocities and Frequencies Kee and Rielly (2004) proposed a semi-empirical method for the in-situ measurement of particle-blade impact velocities and frequencies in a stirred vessel relating to the formation of secondary nucleation sites in crystallization processes. They developed a technique, originally proposed by Nienow (1976), using a thin coating of plasticine on the impeller blades to record craters formed by particle impacts.…”

Correlation Equation of Particle Collision Frequency with Impeller in a Stirred Tank

“…180 mm Fukaya et al, 2003 44.1 kHz f (t) Daubechies 1988 11-22, 5.5-11, 2.8-5.5 kHz f Ϫ1 (t), f Ϫ2 (t), f Ϫ3 (t) Kee and Rielly, 2004;Nienow, 1976Nienow, , 1992Ploß and Mersmann, 1989;Yokota et al, 1999 …”

“…Gahn and Mersmann, 1999; Kee and Rielly, 2004;Ploß and Mersmann, 1989;Yokota et al, 1999 Fukaya et al, 2003;Grootscholten et al, 1982aGrootscholten et al, , 1982bHe et al, 1995;Kee and Rielly, 2004;Nienow, 1976;Takahashi et al, 1992Takahashi et al, , 1993Yokota et al, 1999 Kee and Rielly Eq. 22b Figure 13 h…”