Controlling the size of fragrance microcapsules using designed agitator paddles: Experiment and CFD simulation
Hongbin Zhaoa, Xuening Feia,b,*, Baolian Zhangc, Shuxing Zhaod, Guangmin Lib, Lingyun Caob,*
Controlling the size of fragrance microcapsules using designed agitator paddles was investigated and studied by CFD simulation. First, different fluid flows were established by varying stirring speeds, reactor scales, and agitator paddle design, and the effects of each on particle size and distribution of prepared microcapsules were determined. The experimental results showed that the pattern design of orifices in the plate paddles control the flow field well. Narrow particle-size distributions of the microcapsules were obtained. The fluid flow characteristics including fluid velocity field, turbulent kinetic energy field, and shear stress distribution for the different agitator paddle types in different reaction kettles were simulated using CFD technology. The correlations between simulated data and experimental results were analyzed. Significantly, the simulated average flow velocity was found to show good negative linear correlation with the average particle size of prepared microcapsules, with a correlation of y = –2.166x + 42.626.
Fragrance microcapsule; Melamine-formaldehyde; Particle size; Orifice stirring paddle; CFD simulation