Drop sizes of emulsions related to turbulent energy dissipation rates

Emulsion droplet sizes are compared with rates of turbulent energy dissipation in various types of practical equipment. These rates can be very high locally-up to 400 MW · kg ^-1 in valve homogenizers. The role of adosrbed surface films is discussed, and it is deduced that drop break-up involves an interface from which the adsorbed surface film is removed.

The viscosity of the dispersed phase can be important in determining droplet size, and this is treated theoretically. Results are compared with systems of practical interest, including milk and bitumen emulsions.

The calculations support the contention that turbulence is the basic mechanism of drop break-up.