Meaning
The accidental or intentional incorporation of gas bubbles into a liquid or solid medium during processing defines a physical state that affects material density and structural integrity. Industrial air entrainment often occurs during high speed mixing where the vortex pulls atmosphere into the fluid phase. Small bubbles trapped in the slurry change the volume and the pump efficiency.
This state is distinct from chemical foaming.
Bubble Dynamics
Moving from a lab beaker to a production tank alters how air entrainment develops because the head pressure and shear rates differ. Large scale impellers create higher tip speeds that draw in more gas than small scale pilots. This gas remains trapped if the fluid viscosity is high enough to resist buoyancy.
Production Risk
Excessive gas inclusion reduces the mass of the final product and creates voids in dried layers. If air entrainment happens early in a battery slurry mix, the resulting electrode shows lower capacity than the design specifies. Calling a batch ready for coating without degassing leads to intermittent patches and poor adhesion because the volume of active material is displaced by the gas.
The pump system might also experience cavitation or erratic flow rates when the compressible gas passes through the valve assemblies.
Void Consequence
The presence of these micro cavities weakens the mechanical strength of the cured part or the electrical conductivity of a thin film. When the material enters the drying stage, the expanding gas can burst and leave pinholes. These defects stop the production line and cause substantial waste.
The air entrainment level determines the final density of the cast material.
