| Mixing efficiency of high shear mixer is an importance research topic in the ingredients mixing operations of food and chemical industry. Research had been done on different stators and differnet locations where to put the high shear mixer. Numerical simulation was carried out to find out the effect of them on the flow pattern and energy dissipation rate in the high shear mixer.The effect of stator geometry on the flow pattern and energy dissipation rate in a high shear mixer had been researched using sliding mesh method with standardk ?εturbulence model. The simulation results showed that the flow patterns were basically same for different stators. The jet emerged from the leading edges. At same time, a strong circulation emerged behind the jet. Their radial velocities were basically same, but their tangential velocities were different, stators with narrow openings (small width-to-depth ratio) the liquid at certain distance from stator rotated in the opposite direction to the rotor rotation. This opposite rotation was induced by the strong circulation flows behind the jets. The highest energy dissipation rates all occured at the leading edges of stators due to stagnation in those regions. For all stators, about 50–60% of energy supplied by the rotor dissipated in the rotor swept region and approximately 25% in the jet region. The simulation results also suggest that the energy dissipated in the rotor swept and jet region is linearly dependant of flowrate through stator holes.The effect of different locations where to put the mixing head on the flow pattern and energy dissipation rate in a high shear mixer had also been researched using the same Numerical simulation. It showed that more strong turbulent happened when the mixing head is placed off D/6 of axis, and the flowrate which be jeted through the stator holes will be increased by 8%~11% , but at same time the energy will add 3%~5% of the total energy. The research results can be a reference for optimization of high shear mixer.
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