During the mixing process, all materials involved in the mixing should be evenly distributed. The degree of mixing can be divided into three states: ideal mixing, random mixing, and completely unmixed. The degree of mixing of various materials in the mixer depends on the proportion, physical state and characteristics of the mixed materials, the type of mixer used, and the duration of the mixing operation. The mixing of liquids mainly relies on mechanical stirrers, gas flow, and injection of the mixed liquid, so that the mixed material is stirred to achieve uniform mixing. Stirring causes some liquid to flow, and the flowing liquid pushes the surrounding liquid. Therefore, the liquid forms a circulating flow in the solver. The diffusion between the resulting liquids is called primary convective diffusion. When the flow rate caused by stirring is very high, shear occurs at the interface between the high-speed flow and the surrounding low-speed flow, generating a large number of local vortices. These vortices spread rapidly, and more liquid is sucked into them. The turbulent convective diffusion formed within a small range is called vortex diffusion. When the liquid rotates, the moving part of the mechanical stirrer will also shear the liquid. When the fluid flows through the container wall and various fixed components installed in the container, it can also shear the fluid. These shear effects will lead to the diffusion of many local vortices. The main convection diffusion and vortex diffusion caused by mixing increase the surface area of Molecular diffusion between different liquids, shorten the diffusion distance and shorten the Molecular diffusion time. If the viscosity of the liquid to be mixed is not high, random mixing can be carried out within a short mixing time; If the viscosity is high, a longer mixing time is required.

The mixer manufacturer stated that for liquids with different densities, compositions, and immiscibility, the shear effect and strong turbulence generated by stirring tear the high-density liquid into small droplets, making it evenly dispersed in the main liquid. The flow rate of the liquid generated by mixing must be greater than the settling velocity of the droplets.

The mixing mechanism of a small amount of insoluble powder solid-liquid is different from the mixing mechanism of density and composition. The mixing mechanism of insoluble liquids is the same, but stirring cannot change the particle size of powdered solids. If the settling velocity of solid particles before mixing cannot be less than the flow velocity of the liquid, no matter what mixing method is used, a uniform suspension will not be formed.

The mixer manufacturer stated that the mixing of different slurries mainly involves separating the materials that need to be repeatedly mixed, causing them to undergo strong shear effects such as squeezing, rolling, and squeezing, and then repeatedly merging and kneading to achieve the desired mixing level. This type of mixing is difficult to achieve ideal mixing and can only achieve random mixing. The powder solid is mixed with a small amount of liquid to form a paste, and the mixing mechanism is the same as that of a paste material.